One thing that never gets mentioned is that perceived megapixels and file size can be dramatically increased in software such as Photoshop and Onone. . I took a 16 megapixel image from 25 megabytes to 175 megabytes and made an acceptable 40in by 60in print.
You are the best at covering this stuff. You cover all the bases, and you're no dismissive about any aspects of the subject matter. I don't see anyone else giving such comprehensive explanations that bring the technical side into such a user-friendly explanation. Nice work.
Love your lessons. I used to teach photography classes. So far your are the only one that consider all aspects and variables in a subject matter. Your technical knowledge WOW.. thanks.
8 лет назад+94
As a non-US viewer I would appreciate that you also add a column with metric equivalents. Perhaps there aren't that many of us, but from the comments in previous posts I get the impression that there are at least some. Well, just a suggestion for what is already splendid.
+Richard Rönnbäck Actually the US and UK are the last remaining significant markets using legacy inches. They are actually in the minority. Also US and UK somehow magically know about lens MILLIMETRES - LOL
The reason you need megapixels is so you can crop and process your images. When you straighten, add local contrast (clarity), sharpen, noise reduce, etc. you're doing arithmetic on neighbouring pixel values. That arithmetic will blur features that are close to one pixel on the sensor. But if you have a much higher megapixel image to work with so that the features you're hoping to see are five or ten pixels across, the processing algorithms will work much better and the end result will look sharper even if you export a 2 Megapixel JPEG at the end.
+Pavlos Papageorgiou Extremely well put and very much worth saying. I kept expecting Tony to make this point clearly but I suppose he figured it was a little too complex. He did allude to the idea when he showed the two 300dpi prints that looked different. He was right to emphasize the roll played by the lens but processing deserves more mention than it got.
This is too good of a reply to come from youtube comments. You gave a clear succinct answer that was on topic without being rude to anybody. Are you sure you understand how youtube comments work. ;) Thank you for being a sane voice on here.
Anonymity is a disinhibitor, like alcohol, so a lot of commenters are like bad drunks; feeling empowered but impotent and over-stimulated. They type like they’re drunk too. All those exclamation marks! And they’re never able to spell “they’re” correctly. I misspelled “role” in my original reply.
Very good answer. Yup, if you really haven't bothered to expend your efforts in learning to develop your photographic skills, then I guess you can never have enough gigapixels upon which to base your faint hopes of discovering a recoverable image in post processing. 😜, the Bear
Great video, I have watched so many video of yours and by many other good photographers in youtube but i have to admit but you are the one with the most analysis and i like this, keep going
Tony, you absolutely hit the nail on the head when you said, "300 dpi is the ideal image density for looking at something up close". The key words here are, "for looking at something up close". In my experience, as a professional photographer who has been in commercial photography for over 40 years, the whole dpi or ppi idea is ludicrous. If the 300 dpi theory is correct, then how on earth did they produce 10 x 8 ft billboard posters from my 35mm film transparency images, back in the day? The answer is (surprisingly) that the bigger the image you're printing, then the less dpi you actually need in order to produce what's perceived to be a 'pin sharp' print. Put simply, that's because you view a billboard from about 30ft away. A 20x16" print from a few yards away. And a 5x4" print with your nose pressed against the paper. Only the minuscule 5x4 needs that 300 dpi. If people really want to see their images at their best, then print big and don't be too concerned about the image resolution of your camera's sensor. The human eye won't notice. Indeed, as artists have known for centuries, we're not looking for exact mathematical precision ; the best figurative images are impressionistic. What appears to be a simple crude mark or brushstroke, when viewed from too close, is actually an elegantly expressive rendering when viewed from an appropriate distance. Only "rivet counter" self-appointed photography judges will stick their nose into a 20x16" print -- probably with a magnifying loup -- to base their judgement on what they like to think of as "scientific" judgements. And who cares what such people think. A truly great picture is best viewed in a large print size, where the viewer will stand well back, in order to appreciate the subject and its artistic rendering. Keep up the good work, Tony. You are a brave man to attempt to educate people that great photography is about art, rather than anything that can be broken down into pseudo-science. You'll take a lot of criticism from the rivet counting zealots, but your efforts to educate the wider community are very much appreciated. Rick Bear (Professional, award-winning, photographer.)
Having been using my 16MP for 2 years. Just started looking for a new one, this saved me from the MP myth trap. Bad composed photos with more dots are still bad. Thanks Tony!
I forgot to add that I really enjoy videos that explain tech aspects. I'm just learning photography and you and Chelsea are my favorite resource. Thank You!
Thank you for being smarter then me. Things I would never think would even interest me or have any concern with my photography and your way of explanation just has me hooked and understanding. Thank you again for all that you do!
Thank you for this comprehensive, well-argued and informative video Tony. I especially liked that, by way of reassurance for those who might have been made insecure by the earlier parts of your presentation, you put things into perspective in your conclusion: namely that in the everyday world, viewing distance is a vital consideration. I'd only add that the same point applies to 4k TV's versus 1080p TV's (not 4k monitors, which one views at a far closer distance): the farther away from the screen, the less perceived benefit you will derive. Thanks again.
Yeah! That was clear to me when I upgraded fromm my old tamron 70-200mm 2.8 non VR (9mpix on 70D) to its new Tamron 70-200mm 2.8 VR (16mpix, 70d). Its AMAZING the difference on the results, Im stunned and in love with this lens. I think 24-30 mpix is enough for everybody, 20 is perfect for sports. I've noticed that many lenses doesnt come close to 35 pmpix on 5Ds, only zeiss, thats something to think about.
+Bror Svensson Media It's actually the blending mode. They're just messing around with the curves to create a cross-process effect resulting in terrible greenish and oversaturated skin tones. A blending mode of soft light, color or hue with a 10% opacity would do the trick.
+Bror Svensson Media I think its the Wall paper, it seems to be difficult to light or balance, they have tried to warm up the picture recently, in fact Tony needs to decorate, or he needs to dye his hair violet or something as its camouflaged into the grey (ish) background. ;-)
I think sharpness is somewhat important for me being a filmmaker, I don’t have money for Ziess or Cooke lenses but clarity is still important to my art. You make a lot of sense Tony..... Love this channel
This video is great, especially the calculations for getting between print dimensions and pixels, and perceptual megapixels for the lens camera combination. Brought together things I had noticed and suspected, now I don't have to blindly rely on the table I've been using for print size. THANK YOU! Just started stalking birds in my back yard with my new Zeiss batis 85mm on my Sony a7riii with magnified peak focusing, phenomenal wing detail.
I did an extreme extensive test on this Tony. I am OCD so I did every thing possible with this. I put the 5DSR up against the A7R, against the Canon 6D. Even with pretty extreme crops, it wasn't as night and day as I thought it was going to be. I have a pretty good size print and although the A7R has more resolution, it didn't seem to have much advantage over the 6D. The 5DSR has a lot of details, they are noticeable, especially when cropping. However, even then, it didn't make as big of a deal as I thought it would, unless you're doing a really small crop out of a picture. I could notice that it had more detail, however, the picture on the 6D, which was shot with a really sharp lens, had a ton of detail too and the extra detail I don't think a non photographer would have noticed. BUT with computer monitors, it gets to be even less of an issue. Most people don't have 4k yet, that's only 8 megapixels, we don't have any computer monitor that can see all the resolution of a Canon 6D. Of course we see the difference in zooming in and cropping, but unless it's an extreme crop, it just wasn't as big of a deal as I had made it out to be in my head. The reason I did this test is because I'm a landscaper, I was shooting with the A7R but missed my Canon 5D Mark iii, ergonomics, colors, etc. I thought about going to the 5DSR, so I tested it, but it just didn't offer as much as I thought it would over the Canon 6D. Which is what I have now. I didn't get the 5D Mark iii again because there was nothing it offered me as a landscaper that the 6D didn't have. Now, with that said, with ISO going down, and other things that come with adding more megapixels, I am hoping the next 5D is 28 megapixels. I really feel 28-36 megapixels is the sweet spot right now. The 24-70 2.8 ii and 135mm F/2 from Canon are extremely sharp, they provided a ton of detail with no softness. I used the Zeiss 55mm 1.8 on the A7R as well as the Zeiss 16-35 F/4.
Very interesting. Never heard of the p-mp rating for glass. So what it looks like, is with 36mp and higher sensors we're starting to reach the point of diminishing returns as far as sharpness is concerned - at least with current lens technology?
One thing I notice is that it kind of reach the limit of lens resolution when switching to 50mp 5ds 5dsr as the p-mpx improvement is so minor, even using the Otus 85, the very lengendary lens in the world. 36 to 40 mp seems to be a sweet point as the extra mp improvement doesn't convert to more actual information you get.
Also, it depends on how you print it. I got one of my pictures, which I have taken with a Canon PowerShot S120 (12MP, really not that good), printed out at 23"*31" on a canvas, and it really looks sharp
Also, fractal upsampling (e.g. Iterated Fractal Transform or IFT) enables you to dramatically blow past any such limits. Although the maximum upsizing depends on the source material type (e.g. architectural, nature, portraits, etc), if you use that together with sharpening appropriate to the material and paper material, coating and viewing distance, common low-Nyquist noise ratios in each dimension are 2, 4 and 8 times. In other words, 4. 16 and 64-times the pixels for even low viewing distances. Photoshop provides this as part of their upsampling options, but there are many cheap, free and other options. Years ago, in the 90’s, when Michael Barnsley first created the early IFT fractal encoders, it was used to create the image of a meteor crashed into a building for one of the end of the earth movies of that era. It was made the size of the side of a building from a 2 MB digital file. It looked so photorealistic from the street that they took it down the first week because it was creating traffic jams and crashes.
A bit rough and ready. To more accurately calculate DPI from MPixels (total number of pixels over the sensor area) its A = MPixels/300^2 (if you want to work to 300DPI, if not change the 300 to whatever DPI you want to work with). Then you have to decide what aspect ratio you're sensor is, assuming 1.4 (1.4 x height = width) the height of the photograph will be sqrt(A/1.4) and the width of the photo will be 1.4 x height. For those wanting metric units multiply the calculated height and width by 2.54 to give the dimensions in cm.
Great video. As a self taught hobbyist photographer I never needed to print any of my photos, so I really don't have much knowledge when it comes to printing in general. As of lately though, I've been getting more interested in this topic, and I'm thinking about buying a printer (solely for fun, not an investment of any kind). Great timing hahaha
+Tony Northrup You forgot two of the most important factors. 1. The Bayer sensor. It only achieves 50-55% resolution even without a low-pass filter. This creates a downsampling factor of 2! If you aren't shooting with a monochrome or multi-layer sensor you have to multiply the resolutions of the dpi table by two. 2. Transformation of contrast levels. This essentially explains what you are seeing with the higher-res cameras on DXO. They don't measure pure resolution but sharpness (resolution x micro-contrast). With the higher resolution sensor you are sensing the same lens contrasts at a higher frequency. Once you downscale to a smaller image scale you are transforming those captured contrasts. Low frequency contrasts of the lens become high frequency contrasts of the final output. Those are then perceived as sharpness. That's why the pixel crave does never really end. Definetly way after the two times downsampling factor. That's why one even can see a sharpness difference between an 80 and 60MP digital back on a small web presentation...
I really appreciate the scope and range of the videos you guys put out - techy stuff like this, the new informative podcast and the creative focused 'live' shows really provide fantastic educational content - this has caused me to purchase your books which is I guess is the purpose :)
One thing you didn't mention was cropping. Not crop factor, but cropped image. Everything you said about the lens and DPI still applies here, but even if you never plan to print larger than an 8x10, if you want to be able to crop your image and then print it that size then you will need a higher initial MP because after cropping your usable MP count will be reduced. I want to add that I enjoyed the video as always.
DxO image testing is based on RAW, so images can still be sharpened in post-processing. Also depending on the type of photograph total P-Mpix across the frame might be completely irrelevant. A portrait lens for example might be extremely sharp in the central portion of the frame but unsharp in the extreme corners. You might likely place your subject toward the centre of frame (maybe slightly off-center to rule of thirds nodes), so you may not end up needing the corner pixels for capturing fine detail. Also, for portraits, these corner pixels might very well be representing out-of-focus blur instead of fine detail.
Tony, Fun video. Just one suggestion about a bad habit shown in the video. Image sizes are always in PPI never in DPI. Printer resolution is in DPI and it prints multiple dots for every pixel to generate the abundance of colors digital image can have from 4, 8 or 12 base colors that printer has (depending on number of inks printer has and variable ink density / droplet size). Many new photographers / printers confuse DPI with PPI and it will hurt them in long run having their misconceptions reinforced. There actually are sophisticated, proprietary algorithms that run in printer driver to translate pixels into dots to make the color representation more visually appealing. Then there is of course RGB vs CMYK color space rendering, printer calibration, etc, etc.
For christmas I ordered two high-quality metal prints, 60x40cm (24"x16"), 250€ in total. If you look closely, you'll notice that they scaled down the resolution to probably 180dpi, maybe even less. But it still looks better than any (sharper) print of the same image on paper. Don't get overobsessed with sharpness, folks!
+DLC Spider What was the size of the files you sent in? And when talking about actual print, DPI was at least 600 if not higher as it takes multiple dots of ink to print one pixel of data
One thing I'd add, or address, is the native resolution of any given printer. Canon prints at 300dpi and Epson at 360dpi. Whether the print driver or Photoshop/Lightroom is doing that interpolation makes a difference in print quality, with the later software generally doing a better job. In other words, a 4x6 or 40x60 are printing at 360dpi on an Epson printer no matter what dpi you type into the field. So I'd aim to match Megapixels to native printer dpi for optimal printing quality. Perceived resolution adds another, very real, element to the whole equation. However, it is important to remember that a printer has a native dpi and there is no getting around that.
First of all I really like your calm and technical style :) If we are talking about sharpness, AA filter is the most important thing in my opinion. You will never get sharper images with a regular A7 with a Zeiss Otus than an A7r with a $250 Rokinon 85mm 1.8. It is a fact that people just ignore. A Canon 5D M3 can never be as sharp as a micro four thirds camera with no AA filter in it. I have tested it so many times. I don't understand people buying a $2000 lens for their A7II for a sharper image. It will never be as sharp as an original A7R if you avoid the shutter shock and use it at reasonable shutter speeds. This whole argument is pointless. Yes, better lenses usually create sharper images but seriously nothing can effect micro sharpness more than AA filters. Take care!
This is the best vid I’ve watched. I shoot in crop mode all the time with my a7iii because I think 10mp is enough. I’m kind stop doing it now, the end of the day, I need to print 8x10, I don’t think I have enough p-mpix for a sharp print
I use PPI when talking about digital files, and DPI when talking about actual print density. This way there is no confusion between file export setting and printer settings. I have seen files saved at 600 PPI becouse they tried to match printer's 600 DPI
What I find the most challenging in resolution compartment is photo wallpapers. They tend to occupy whole wall in a room and you come close to them often. But theres always image stacking and stitching techniques...
There you go again +Tony Northrup bringing your science mumbo jumbo into photography :-) . Very we ll done video you took the highly technical info and broke it down in terms that don't take a PhD in Mathematics to understand. Keep up the great work!
Printing aside: I was happy with the 22.3 megapixels on my 5DMKiii.. that is until I recently upgraded to a 32" 4K monitor. I now find that I'm suffering from pixel peeping disease (this is something I've never had before), all because I can now view my photos at much nearer their 100% size on screen. This is the only reason why I am lusting after more megapixels.
Hi Tony, do you mind making a video explaining the difference between depth of field and lens compression. i think its a really great topic to cover since a lot of people do not know the difference between those two
All I need is one gigapixel camera, 30 f stop dynamic range and color space larger than pro photo. We could add to that no noise at all and VR that will give you no camera shake under any circumstances, make it very cheep and everyone will be happy.:)
Tony I have a question and you seem like the right guy to answer it. I have a pentax k-3ii with a 100mm macro lens and a 1.4x teleconverter. The pentax has a 1.5x crop factor and the macro lens shoots 1:1 magnification. Along with the teleconverter, what is my total magnification number at the closest focusing distance on the macro lens with the crop factor of the camera? How do I work out that formula? And what is my overall equivalent crop factor with the camera and the teleconverter?
An image will subtend a comfortable viewing angle when the throw/height ratio is around 5 to 6. You can use that to work the calculations in the other direction when selecting print size. This is an old movie theater rule. YMMV.
I remember as a kid mydad had banner canvases for products he handled. I was surprised to see groups of color dots with alot of white space between elements. Opened one up a little and went to the other side of the warehouse to see the image.
Great video! I usually don't care too much about dpi and megapixel, but now after I'm watching this video, I feel like I could optimize my dpi setting and hopefully get a better result for both digital viewing and printing. Also this is a good reminder that I shouldn't adapt my full-frame lens to my micro four thirds cameras if I want higher perceptual megapixel.
Bravo! finally somebody said the sharpness is not the most important thing.... because here on web everybody are speaking about it... almost nobody about the main thing ................. composition
Totally agree here. My pro lab had a good special on 20"x30", so I sent a test print I was happy with to see how it would go. I've always been happy with the quality, but I didn't really know how it would go, especially as at 300dpi it 'should' be 6000x9000!I have the 24mp Sony A77ii, (6000x4000) and used the 'kit' lens 16-50 2.8. The 20x30 came back looking amazing, even with pixel peeping in really close. I have previously done a billboard using a 10mp A100 too, and it came out looking great, but I certainly wasn't able to look at that one up too close! For shooting sports especially, I love being able to heavily crop and still have have decent sized images though, so I don't think I could go lower than 24mp again!
Hey Tony. Correct me if im wrong but, one does not need an optically perfect lens, just one which out resolves the sensor on the settings you are using
+Paul Redman Lenses can't really "outresolve" the sensor; they are always something less than perfect, and anything less than perfect will degrade the detail captured by the sensor from its maximum megapixel count.
i haven't printed a pic in years and may never again. all my pics are viewed on my small cell or my huge hi-def tv screens. for the latter, you bet the megapixels count. the big 4K screens i suspect are where a lot of our favourite photos end up looping, now. i want my pics to take advantage of these big, hi-rez canvasses. thanks for all the great vids!
Interesting to see the two schools of thought in these comments... One side says why worry about all the math and numbers, just take the picture because at the end of day it's art. The other side says it's important to know the science underneath the surface, because understanding it inherently leads you to being a better artist.
Any idea why the DXO p-pmix scores are consistently higher for the Canon T5I than the same lenses on the canon 7D mark II? I was wanting to make the upgrade but I'm confused that there is such a consistent lower scores for the sharpness of the 7D mark II. Am I misinterpreting something?
In a video you said that using a full frame lens on a micro four thirds camera produces less sharp images because the pixel density of micro four thirds is higher than full frame cameras. Am I missing something here?
The 300 dpi came from the printing industry when it started going digital. It’s the metric equivalent of 150 lines per inch. Which is what most of the large printing presses of the day were able to produce to get an a sharp image. In printing a picture is broken down to tiny dots that a printing press can put on paper. Today they have digital presses. I retired from the industry two years ago but as of that time digital presses were not equal in quality but getting there. Sharpness was very important. Because there’s always a loss and sharpness going from one media to another. Copying a digital file to another digital file is an exact copy, no loss. But then going to paper it is now second-generation. And that’s whether it’s a digital press or not.
Nowadays most people probably view photos on screen. As screen resolution increases beyond the x-y of the still image, having more megapixels is a very good thing. Those old 1-2mp early digital camera images just don't look very good anymore. The same thing might end up happening to 10mp images as future screens are developed (or VR viewing of images).
Hey Toni and Chelsea, thanks for your Videos. Just recently I upgraded from my Nikon D5100 with Tamron 18-270 to a D7200 with a Sigma 18-35 F1.8 and a Nikkor 50 F1.8. I have now received an offer from my local dealer for a Nikon 70-200 F2.8 VR I. Its right now beeing overhauled At Nikon Germany and afterwards I could buy it for 530€ (roughly 700 USD), including one year warranty. At that price point the only alternative would be the Tamron Macro 70-200 F2.8. I am wondering now, whether or not I should go for it. Those lenses usually sale for 750-1050€, so its a very good price. My Main purpose for it would be Portrait (10%), Airport Spotting (50%) and Animals like birds, or sporting events (40%). I would always use the lens without a tripod, as its to limiting for me to carry one around. For the given purpose, would you take the VR1 at that price, or would you skip it?
What about scaling images before print? If I have an 18MP raw file and process it in lightroom, and apply output sharpening for print, should I scale it down to fit my 8x10 at 300dpi, or send it to the printer at the full 18MP resolution?
The 5X7" print size is close to A5 paper size. The 8X10" print size is close to A4 paper size. The 11x14" print size is close to the A3 paper size. The maximum paper size of most affordable home printers is A4 and a 8 Megapixels camera is theoretically enough for an A4 print of a photo. However what is more important than megapixels is the sharpness of the lens. For example the lenses of nearly all smartphones with more than 8 megapixels sensors are not sharp. The quality of a print is pointless if a photo isn't very sharp. Of course there are some digital sharpening techniques but a soft photo is a soft photo. More and more megapixels and raw photo files are always useful with digital image processing. However very few bother or know raw photo processing and the digital processing of photos. For nearly all amateurs photographers the jpeg photos from their cameras are fine and for them a 20-24 Megapixel camerawork a decent prime lens (not kit lens) is more than enough for A4 prints.
Your videos are amazing. I have learned so much from you and I haven't purchased my first DSLR yet! I've narrowed it down to the 70d and 80d for my amateur photography purposes. I'm not interested in a lot of video. I think after watching this you've helped me see that it may be best to buy the 70d and use the difference to purchase an upgraded lens from the kit lens and my pictures will be sharper. What do you think? Thanks again for all of your videos!!!
Cory Armitage What thank you and thank you. Buy a gh5 which have many cheap and quality lenses, or go for a fuji which doesnt need editing in order to have great photos. You will return from your vacation with 3000-5000 photos. You will stay a week inside in front of the pc to edit all? Use your brain! Thank you and thank you. Pfffff.
Thanks Tony for the great video. I worked with a press who did my phonebook. They have machines now who can up to 500 ppi! No joking. So we could replace 300 number with 500. I use a 5DII and we could print a at max 350 ppi for the quality which is great. A friend of mine made a phonebook at the same press. He shot with a Hasselblad and had to scale down! Never seen so much detail in a phonebook :D
Hi Tony. Wasn't your formula predicting the 18PMP scoring Sigma 24-105mm on a 5D3 would rise by 14.5MP to give 32.5 PMP on a 5DsR? Seems your formula should be MPup/4 rather than MPup/2.
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One thing that never gets mentioned is that perceived megapixels and file size can be dramatically increased in software such as Photoshop and Onone.
. I took a 16 megapixel image from 25 megabytes to 175 megabytes and made an acceptable 40in by 60in print.
You really are the most reasonable and honest photography teacher out there. I like your straight forward style. Much appreciated.
Thanks!
totally agree!
I love the fact he provided everything with real facts
+1
You are the best at covering this stuff. You cover all the bases, and you're no dismissive about any aspects of the subject matter. I don't see anyone else giving such comprehensive explanations that bring the technical side into such a user-friendly explanation. Nice work.
+Terence Kearns Thanks!
Love your lessons. I used to teach photography classes. So far your are the only one that consider all aspects and variables in a subject matter. Your technical knowledge WOW.. thanks.
As a non-US viewer I would appreciate that you also add a column with metric equivalents. Perhaps there aren't that many of us, but from the comments in previous posts I get the impression that there are at least some. Well, just a suggestion for what is already splendid.
+Richard Rönnbäck
1 inch = 25.4 mm :)
+ObelixCMM And for rough estimations I use: 4 inches = 10 cm, 3 feet = 1 meter
+Dmitry Rudoy yeah & with your standard of accuracy & precision in establishing definitions, your mother is a virgin :-)
+Richard Rönnbäck Actually the US and UK are the last remaining significant markets using legacy inches. They are actually in the minority. Also US and UK somehow magically know about lens MILLIMETRES - LOL
Actually I come from the UK and was brought on Imperial feet and inches etc and then we had metrication forced on us! Rant over.. :-)
The reason you need megapixels is so you can crop and process your images. When you straighten, add local contrast (clarity), sharpen, noise reduce, etc. you're doing arithmetic on neighbouring pixel values. That arithmetic will blur features that are close to one pixel on the sensor. But if you have a much higher megapixel image to work with so that the features you're hoping to see are five or ten pixels across, the processing algorithms will work much better and the end result will look sharper even if you export a 2 Megapixel JPEG at the end.
+Pavlos Papageorgiou Extremely well put and very much worth saying. I kept expecting Tony to make this point clearly but I suppose he figured it was a little too complex. He did allude to the idea when he showed the two 300dpi prints that looked different. He was right to emphasize the roll played by the lens but processing deserves more mention than it got.
This is too good of a reply to come from youtube comments. You gave a clear succinct answer that was on topic without being rude to anybody. Are you sure you understand how youtube comments work. ;) Thank you for being a sane voice on here.
Anonymity is a disinhibitor, like alcohol, so a lot of commenters are like bad drunks; feeling empowered but impotent and over-stimulated.
They type like they’re drunk too. All those exclamation marks! And they’re never able to spell “they’re” correctly. I misspelled “role” in my original reply.
Very good answer. Yup, if you really haven't bothered to expend your efforts in learning to develop your photographic skills, then I guess you can never have enough gigapixels upon which to base your faint hopes of discovering a recoverable image in post processing.
😜, the Bear
Great video, I have watched so many video of yours and by many other good photographers in youtube but i have to admit but you are the one with the most analysis and i like this, keep going
Tony, you absolutely hit the nail on the head when you said, "300 dpi is the ideal image density for looking at something up close". The key words here are, "for looking at something up close".
In my experience, as a professional photographer who has been in commercial photography for over 40 years, the whole dpi or ppi idea is ludicrous. If the 300 dpi theory is correct, then how on earth did they produce 10 x 8 ft billboard posters from my 35mm film transparency images, back in the day?
The answer is (surprisingly) that the bigger the image you're printing, then the less dpi you actually need in order to produce what's perceived to be a 'pin sharp' print.
Put simply, that's because you view a billboard from about 30ft away. A 20x16" print from a few yards away. And a 5x4" print with your nose pressed against the paper. Only the minuscule 5x4 needs that 300 dpi.
If people really want to see their images at their best, then print big and don't be too concerned about the image resolution of your camera's sensor. The human eye won't notice. Indeed, as artists have known for centuries, we're not looking for exact mathematical precision ; the best figurative images are impressionistic. What appears to be a simple crude mark or brushstroke, when viewed from too close, is actually an elegantly expressive rendering when viewed from an appropriate distance.
Only "rivet counter" self-appointed photography judges will stick their nose into a 20x16" print -- probably with a magnifying loup -- to base their judgement on what they like to think of as "scientific" judgements. And who cares what such people think.
A truly great picture is best viewed in a large print size, where the viewer will stand well back, in order to appreciate the subject and its artistic rendering.
Keep up the good work, Tony. You are a brave man to attempt to educate people that great photography is about art, rather than anything that can be broken down into pseudo-science. You'll take a lot of criticism from the rivet counting zealots, but your efforts to educate the wider community are very much appreciated.
Rick Bear
(Professional, award-winning, photographer.)
As usual Tony, a very sensible, level-headed point of view. Keep up the good work!
+David Greenwell Thanks!
I love how technical and specific are your lessons. Thank you for so informative and useful classes in youtube.
Having been using my 16MP for 2 years. Just started looking for a new one, this saved me from the MP myth trap. Bad composed photos with more dots are still bad. Thanks Tony!
As usual, an eye opening video from Tony. Thank you. I have great respect for you & you have taught me a lot
+Omar Omari Glad to help!
Another stunning video that helps photographers, and is presented in a methodical way and with great substance, thanks again
Love these videos where you really break it down to the technical info. Thanks for the video as always!
Tony always does a great job on the technical descriptions.
I forgot to add that I really enjoy videos that explain tech aspects. I'm just learning photography and you and Chelsea are my favorite resource. Thank You!
I always learn so much when watch your videos. Thanks.
Jon
Thank you for being smarter then me. Things I would never think would even interest me or have any concern with my photography and your way of explanation just has me hooked and understanding. Thank you again for all that you do!
"Sharpness is not everything" somewhere Jared Polin is crying ;)
Jared is a quack anyway, let him cry all he wants xD
+Appelcaster JP is the MTV of YT... The Northrups are like old-school Discovery Channel.
+martinaee You mean when discovery was actually educational?
+driverv86 Hence: "old school" :)
martinaee I miss that version.
Thank you for this comprehensive, well-argued and informative video Tony. I especially liked that, by way of reassurance for those who might have been made insecure by the earlier parts of your presentation, you put things into perspective in your conclusion: namely that in the everyday world, viewing distance is a vital consideration. I'd only add that the same point applies to 4k TV's versus 1080p TV's (not 4k monitors, which one views at a far closer distance): the farther away from the screen, the less perceived benefit you will derive. Thanks again.
Yeah! That was clear to me when I upgraded fromm my old tamron 70-200mm 2.8 non VR (9mpix on 70D) to its new Tamron 70-200mm 2.8 VR (16mpix, 70d). Its AMAZING the difference on the results, Im stunned and in love with this lens. I think 24-30 mpix is enough for everybody, 20 is perfect for sports. I've noticed that many lenses doesnt come close to 35 pmpix on 5Ds, only zeiss, thats something to think about.
It also used to suck to have to crop an image only to end up with 1-2 mp worth leftover back when I was shooting with much lower megapixel cameras.
Those are some funky ass colors, i think the saturation slider is a bit off haha
+Bror Svensson Media It's actually the blending mode. They're just messing around with the curves to create a cross-process effect resulting in terrible greenish and oversaturated skin tones. A blending mode of soft light, color or hue with a 10% opacity would do the trick.
+Bror Svensson Media I think its the Wall paper, it seems to be difficult to light or balance, they have tried to warm up the picture recently, in fact Tony needs to decorate, or he needs to dye his hair violet or something as its camouflaged into the grey (ish) background. ;-)
He is using a polarization filter as well, apparently to cut out the update effect of the TV.
I think sharpness is somewhat important for me being a filmmaker, I don’t have money for Ziess or Cooke lenses but clarity is still important to my art. You make a lot of sense Tony..... Love this channel
You are kind of the "Fred Picker" (teacher of film photography) of the digital world.
Good work.
This video is great, especially the calculations for getting between print dimensions and pixels, and perceptual megapixels for the lens camera combination. Brought together things I had noticed and suspected, now I don't have to blindly rely on the table I've been using for print size. THANK YOU! Just started stalking birds in my back yard with my new Zeiss batis 85mm on my Sony a7riii with magnified peak focusing, phenomenal wing detail.
I did an extreme extensive test on this Tony. I am OCD so I did every thing possible with this. I put the 5DSR up against the A7R, against the Canon 6D. Even with pretty extreme crops, it wasn't as night and day as I thought it was going to be. I have a pretty good size print and although the A7R has more resolution, it didn't seem to have much advantage over the 6D. The 5DSR has a lot of details, they are noticeable, especially when cropping. However, even then, it didn't make as big of a deal as I thought it would, unless you're doing a really small crop out of a picture. I could notice that it had more detail, however, the picture on the 6D, which was shot with a really sharp lens, had a ton of detail too and the extra detail I don't think a non photographer would have noticed. BUT with computer monitors, it gets to be even less of an issue. Most people don't have 4k yet, that's only 8 megapixels, we don't have any computer monitor that can see all the resolution of a Canon 6D. Of course we see the difference in zooming in and cropping, but unless it's an extreme crop, it just wasn't as big of a deal as I had made it out to be in my head. The reason I did this test is because I'm a landscaper, I was shooting with the A7R but missed my Canon 5D Mark iii, ergonomics, colors, etc. I thought about going to the 5DSR, so I tested it, but it just didn't offer as much as I thought it would over the Canon 6D. Which is what I have now. I didn't get the 5D Mark iii again because there was nothing it offered me as a landscaper that the 6D didn't have. Now, with that said, with ISO going down, and other things that come with adding more megapixels, I am hoping the next 5D is 28 megapixels. I really feel 28-36 megapixels is the sweet spot right now. The 24-70 2.8 ii and 135mm F/2 from Canon are extremely sharp, they provided a ton of detail with no softness. I used the Zeiss 55mm 1.8 on the A7R as well as the Zeiss 16-35 F/4.
RUclipsr: "I watched the first 10 seconds of your video, and here is why you are wrong about all the things I'm guessing you said!"
Very interesting. Never heard of the p-mp rating for glass. So what it looks like, is with 36mp and higher sensors we're starting to reach the point of diminishing returns as far as sharpness is concerned - at least with current lens technology?
"just want to let you know". -Tony ruining everyone's dreamy photography misconceptions with facts...Hahaha! I love it. Tony is too smart.
I love how you answered it in the first 5 seconds :D
One thing I notice is that it kind of reach the limit of lens resolution when switching to 50mp 5ds 5dsr as the p-mpx improvement is so minor, even using the Otus 85, the very lengendary lens in the world. 36 to 40 mp seems to be a sweet point as the extra mp improvement doesn't convert to more actual information you get.
A great educational video, Tony, thanks a lot for the time spent on this. Very clear and extremely informative.
Also, it depends on how you print it. I got one of my pictures, which I have taken with a Canon PowerShot S120 (12MP, really not that good), printed out at 23"*31" on a canvas, and it really looks sharp
another terrific offering, Tony....thank you
+Neil Hersh Thanks, Neil!
REALLY DETAILED VIDEO. LOOKING FORWARD TO SEE SOME SMARTPHONE CAMERA REVIEW FROM THE EXPERT. THANKING YOU IN ADVANCE
Today I bought your book here in Brazil! It will arrive in a few days. I'm excited! =D
Also, fractal upsampling (e.g. Iterated Fractal Transform or IFT) enables you to dramatically blow past any such limits. Although the maximum upsizing depends on the source material type (e.g. architectural, nature, portraits, etc), if you use that together with sharpening appropriate to the material and paper material, coating and viewing distance, common low-Nyquist noise ratios in each dimension are 2, 4 and 8 times. In other words, 4. 16 and 64-times the pixels for even low viewing distances. Photoshop provides this as part of their upsampling options, but there are many cheap, free and other options. Years ago, in the 90’s, when Michael Barnsley first created the early IFT fractal encoders, it was used to create the image of a meteor crashed into a building for one of the end of the earth movies of that era. It was made the size of the side of a building from a 2 MB digital file. It looked so photorealistic from the street that they took it down the first week because it was creating traffic jams and crashes.
A bit rough and ready. To more accurately calculate DPI from MPixels (total number of pixels over the sensor area) its
A = MPixels/300^2 (if you want to work to 300DPI, if not change the 300 to whatever DPI you want to work with). Then you have to decide what aspect ratio you're sensor is, assuming 1.4 (1.4 x height = width) the height of the photograph will be sqrt(A/1.4) and the width of the photo will be 1.4 x height. For those wanting metric units multiply the calculated height and width by 2.54 to give the dimensions in cm.
Great video. As a self taught hobbyist photographer I never needed to print any of my photos, so I really don't have much knowledge when it comes to printing in general. As of lately though, I've been getting more interested in this topic, and I'm thinking about buying a printer (solely for fun, not an investment of any kind). Great timing hahaha
The end was so motivating, thank you guys
+Tony Northrup
You forgot two of the most important factors.
1. The Bayer sensor. It only achieves 50-55% resolution even without a low-pass filter. This creates a downsampling factor of 2!
If you aren't shooting with a monochrome or multi-layer sensor you have to multiply the resolutions of the dpi table by two.
2. Transformation of contrast levels. This essentially explains what you are seeing with the higher-res cameras on DXO. They don't measure pure resolution but sharpness (resolution x micro-contrast). With the higher resolution sensor you are sensing the same lens contrasts at a higher frequency. Once you downscale to a smaller image scale you are transforming those captured contrasts. Low frequency contrasts of the lens become high frequency contrasts of the final output. Those are then perceived as sharpness. That's why the pixel crave does never really end. Definetly way after the two times downsampling factor.
That's why one even can see a sharpness difference between an 80 and 60MP digital back on a small web presentation...
Which yields better low-light image quality? A high megapixel image down sampled or a sensor with large pixels.
I loved the way you explained. you are a treasure.
will you please make a video about pixel size or Pixel pitch
I really appreciate the scope and range of the videos you guys put out - techy stuff like this, the new informative podcast and the creative focused 'live' shows really provide fantastic educational content - this has caused me to purchase your books which is I guess is the purpose :)
Thanks, Dave!
One thing you didn't mention was cropping. Not crop factor, but cropped image. Everything you said about the lens and DPI still applies here, but even if you never plan to print larger than an 8x10, if you want to be able to crop your image and then print it that size then you will need a higher initial MP because after cropping your usable MP count will be reduced.
I want to add that I enjoyed the video as always.
Great video as usual! Just one thing, aren't recent videos affected by a blue tint? Tony's hair looks weird with this color temperature
DxO image testing is based on RAW, so images can still be sharpened in post-processing.
Also depending on the type of photograph total P-Mpix across the frame might be completely irrelevant. A portrait lens for example might be extremely sharp in the central portion of the frame but unsharp in the extreme corners. You might likely place your subject toward the centre of frame (maybe slightly off-center to rule of thirds nodes), so you may not end up needing the corner pixels for capturing fine detail. Also, for portraits, these corner pixels might very well be representing out-of-focus blur instead of fine detail.
Tony, Fun video. Just one suggestion about a bad habit shown in the video. Image sizes are always in PPI never in DPI. Printer resolution is in DPI and it prints multiple dots for every pixel to generate the abundance of colors digital image can have from 4, 8 or 12 base colors that printer has (depending on number of inks printer has and variable ink density / droplet size). Many new photographers / printers confuse DPI with PPI and it will hurt them in long run having their misconceptions reinforced. There actually are sophisticated, proprietary algorithms that run in printer driver to translate pixels into dots to make the color representation more visually appealing. Then there is of course RGB vs CMYK color space rendering, printer calibration, etc, etc.
For christmas I ordered two high-quality metal prints, 60x40cm (24"x16"), 250€ in total. If you look closely, you'll notice that they scaled down the resolution to probably 180dpi, maybe even less. But it still looks better than any (sharper) print of the same image on paper. Don't get overobsessed with sharpness, folks!
+DLC Spider What was the size of the files you sent in? And when talking about actual print, DPI was at least 600 if not higher as it takes multiple dots of ink to print one pixel of data
ObelixCMM I don't know. Went to a store and they said, they have to scale it down a little but not by how much...
One thing I'd add, or address, is the native resolution of any given printer. Canon prints at 300dpi and Epson at 360dpi. Whether the print driver or Photoshop/Lightroom is doing that interpolation makes a difference in print quality, with the later software generally doing a better job. In other words, a 4x6 or 40x60 are printing at 360dpi on an Epson printer no matter what dpi you type into the field. So I'd aim to match Megapixels to native printer dpi for optimal printing quality. Perceived resolution adds another, very real, element to the whole equation. However, it is important to remember that a printer has a native dpi and there is no getting around that.
Very informative video. Thank you for all the useful information you have posted!
First of all I really like your calm and technical style :)
If we are talking about sharpness, AA filter is the most important thing in my opinion. You will never get sharper images with a regular A7 with a Zeiss Otus than an A7r with a $250 Rokinon 85mm 1.8. It is a fact that people just ignore.
A Canon 5D M3 can never be as sharp as a micro four thirds camera with no AA filter in it. I have tested it so many times.
I don't understand people buying a $2000 lens for their A7II for a sharper image. It will never be as sharp as an original A7R if you avoid the shutter shock and use it at reasonable shutter speeds.
This whole argument is pointless. Yes, better lenses usually create sharper images but seriously nothing can effect micro sharpness more than AA filters.
Take care!
This is the best vid I’ve watched. I shoot in crop mode all the time with my a7iii because I think 10mp is enough. I’m kind stop doing it now, the end of the day, I need to print 8x10, I don’t think I have enough p-mpix for a sharp print
Definitely not; you definitely want to use all 24 MP. Plus, 8x10 prints are really small.
Great video! This was very educational. Thanks, Tony.
Awesome video Tony, thanks for so much valuable information.
Fantastic. Thank you Maybe half my heated discussions about gear would be stopped dead if people watched this clip.
I use PPI when talking about digital files, and DPI when talking about actual print density. This way there is no confusion between file export setting and printer settings. I have seen files saved at 600 PPI becouse they tried to match printer's 600 DPI
What I find the most challenging in resolution compartment is photo wallpapers. They tend to occupy whole wall in a room and you come close to them often. But theres always image stacking and stitching techniques...
There you go again +Tony Northrup bringing your science mumbo jumbo into photography :-) . Very we ll done video you took the highly technical info and broke it down in terms that don't take a PhD in Mathematics to understand. Keep up the great work!
Wow Tony you made me really understand megapixels concept. I get it! Thanks Tony
This is a very confusing subject at least for the math challenged (like me) but this is the clearest explanation I've seen.
It would be useful to use centimeters also for those who are not accustomed to inches. Congratulations on your channel! Is very useful for me.
Printing aside: I was happy with the 22.3 megapixels on my 5DMKiii.. that is until I recently upgraded to a 32" 4K monitor. I now find that I'm suffering from pixel peeping disease (this is something I've never had before), all because I can now view my photos at much nearer their 100% size on screen. This is the only reason why I am lusting after more megapixels.
Merci pour les super tutoriels que vous nous offrez chaque semaine! Thanks your are the greats person!
Thanks for the insightful and well thought out video Tony! I think it would be useful to do a similar one for bit depth.
So if I can get 8 perceived megapixels is that just good enough for 8x10s??
Hi Tony, do you mind making a video explaining the difference between depth of field and lens compression. i think its a really great topic to cover since a lot of people do not know the difference between those two
All I need is one gigapixel camera, 30 f stop dynamic range and color space larger than pro photo. We could add to that no noise at all and VR that will give you no camera shake under any circumstances, make it very cheep and everyone will be happy.:)
Tony I have a question and you seem like the right guy to answer it. I have a pentax k-3ii with a 100mm macro lens and a 1.4x teleconverter. The pentax has a 1.5x crop factor and the macro lens shoots 1:1 magnification. Along with the teleconverter, what is my total magnification number at the closest focusing distance on the macro lens with the crop factor of the camera? How do I work out that formula? And what is my overall equivalent crop factor with the camera and the teleconverter?
Professor Northrup..... Great video, interesting discussion. When it gets heavy in the minutia debate, I say just go out and shoot!
An image will subtend a comfortable viewing angle when the throw/height ratio is around 5 to 6. You can use that to work the calculations in the other direction when selecting print size. This is an old movie theater rule. YMMV.
I would also add that more MP lets your crop the photo more, but great video!
I remember as a kid mydad had banner canvases for products he handled. I was surprised to see groups of color dots with alot of white space between elements. Opened one up a little and went to the other side of the warehouse to see the image.
Great video! I usually don't care too much about dpi and megapixel, but now after I'm watching this video, I feel like I could optimize my dpi setting and hopefully get a better result for both digital viewing and printing. Also this is a good reminder that I shouldn't adapt my full-frame lens to my micro four thirds cameras if I want higher perceptual megapixel.
The dpi setting shouldn't make any difference.
+Tony Northrup thanks Tony, will keep it in mind.
Bravo! finally somebody said the sharpness is not the most important thing.... because here on web everybody are speaking about it... almost nobody about the main thing ................. composition
Totally agree here. My pro lab had a good special on 20"x30", so I sent a test print I was happy with to see how it would go. I've always been happy with the quality, but I didn't really know how it would go, especially as at 300dpi it 'should' be 6000x9000!I have the 24mp Sony A77ii, (6000x4000) and used the 'kit' lens 16-50 2.8. The 20x30 came back looking amazing, even with pixel peeping in really close. I have previously done a billboard using a 10mp A100 too, and it came out looking great, but I certainly wasn't able to look at that one up too close! For shooting sports especially, I love being able to heavily crop and still have have decent sized images though, so I don't think I could go lower than 24mp again!
Hey Tony. Correct me if im wrong but, one does not need an optically perfect lens, just one which out resolves the sensor on the settings you are using
+Paul Redman Lenses can't really "outresolve" the sensor; they are always something less than perfect, and anything less than perfect will degrade the detail captured by the sensor from its maximum megapixel count.
i haven't printed a pic in years and may never again. all my pics are viewed on my small cell or my huge hi-def tv screens. for the latter, you bet the megapixels count. the big 4K screens i suspect are where a lot of our favourite photos end up looping, now. i want my pics to take advantage of these big, hi-rez canvasses.
thanks for all the great vids!
A 4K screen can only display 8 mp. So pretty much any camera you can buy is good enough for that.
Another great explanation. Thanks.
Technically fantastic video. Thanks!
Interesting to see the two schools of thought in these comments...
One side says why worry about all the math and numbers, just take the picture because at the end of day it's art.
The other side says it's important to know the science underneath the surface, because understanding it inherently leads you to being a better artist.
Any idea why the DXO p-pmix scores are consistently higher for the Canon T5I than the same lenses on the canon 7D mark II? I was wanting to make the upgrade but I'm confused that there is such a consistent lower scores for the sharpness of the 7D mark II. Am I misinterpreting something?
In a video you said that using a full frame lens on a micro four thirds camera produces less sharp images because the pixel density of micro four thirds is higher than full frame cameras. Am I missing something here?
The 300 dpi came from the printing industry when it started going digital. It’s the metric equivalent of 150 lines per inch. Which is what most of the large printing presses of the day were able to produce to get an a sharp image. In printing a picture is broken down to tiny dots that a printing press can put on paper. Today they have digital presses. I retired from the industry two years ago but as of that time digital presses were not equal in quality but getting there. Sharpness was very important. Because there’s always a loss and sharpness going from one media to another. Copying a digital file to another digital file is an exact copy, no loss. But then going to paper it is now second-generation. And that’s whether it’s a digital press or not.
Your book Stunning Digital Photography contains this kind of information? It is really useful information
Very sensible information, thanks 🙂
Nowadays most people probably view photos on screen. As screen resolution increases beyond the x-y of the still image, having more megapixels is a very good thing. Those old 1-2mp early digital camera images just don't look very good anymore. The same thing might end up happening to 10mp images as future screens are developed (or VR viewing of images).
Hi Sir Tony😄 I just want to know if the Nikon D5300 a good camera even though it have a 24.1 megapixels.
Is it a good camera??? Thank you😊
Yes, it's a great camera.
Hey Toni and Chelsea,
thanks for your Videos.
Just recently I upgraded from my Nikon D5100 with Tamron 18-270 to a D7200 with a Sigma 18-35 F1.8 and a Nikkor 50 F1.8.
I have now received an offer from my local dealer for a Nikon 70-200 F2.8 VR I. Its right now beeing overhauled At Nikon Germany and afterwards I could buy it for 530€ (roughly 700 USD), including one year warranty. At that price point the only alternative would be the Tamron Macro 70-200 F2.8. I am wondering now, whether or not I should go for it. Those lenses usually sale for 750-1050€, so its a very good price.
My Main purpose for it would be Portrait (10%), Airport Spotting (50%) and Animals like birds, or sporting events (40%). I would always use the lens without a tripod, as its to limiting for me to carry one around.
For the given purpose, would you take the VR1 at that price, or would you skip it?
+qqqqhuz Sorry, I don't know. We never tested the VR I.
this video is really useful, thumbs up good content
Great video.
Very informative
I think I should install a 50 foot barrier between my Pics on the wall and my guests view point. They’ll be outside my house already! Lol
What about scaling images before print? If I have an 18MP raw file and process it in lightroom, and apply output sharpening for print, should I scale it down to fit my 8x10 at 300dpi, or send it to the printer at the full 18MP resolution?
The 5X7" print size is close to A5 paper size.
The 8X10" print size is close to A4 paper size.
The 11x14" print size is close to the A3 paper size.
The maximum paper size of most affordable home printers is A4 and a 8 Megapixels camera is theoretically enough for an A4 print of a photo.
However what is more important than megapixels is the sharpness of the lens. For example the lenses of nearly all smartphones with more than 8 megapixels sensors are not sharp. The quality of a print is pointless if a photo isn't very sharp. Of course there are some digital sharpening techniques but a soft photo is a soft photo.
More and more megapixels and raw photo files are always useful with digital image processing.
However very few bother or know raw photo processing and the digital processing of photos.
For nearly all amateurs photographers the jpeg photos from their cameras are fine and for them a 20-24 Megapixel camerawork a decent prime lens (not kit lens) is more than enough for A4 prints.
Can't wait for the 1DX II preview, Tony! When do you make it?
Your videos are amazing. I have learned so much from you and I haven't purchased my first DSLR yet! I've narrowed it down to the 70d and 80d for my amateur photography purposes. I'm not interested in a lot of video. I think after watching this you've helped me see that it may be best to buy the 70d and use the difference to purchase an upgraded lens from the kit lens and my pictures will be sharper. What do you think?
Thanks again for all of your videos!!!
Cory Armitage
What thank you and thank you. Buy a gh5 which have many cheap and quality lenses, or go for a fuji which doesnt need editing in order to have great photos. You will return from your vacation with 3000-5000 photos. You will stay a week inside in front of the pc to edit all? Use your brain! Thank you and thank you. Pfffff.
Cory Armitage lol you buy 70D and 80D for begginer? Nah waste should buy 600D and some nice lenses
Thanks Tony for the great video. I worked with a press who did my phonebook. They have machines now who can up to 500 ppi! No joking. So we could replace 300 number with 500. I use a 5DII and we could print a at max 350 ppi for the quality which is great. A friend of mine made a phonebook at the same press. He shot with a Hasselblad and had to scale down! Never seen so much detail in a phonebook :D
Lighting is what’s most important to any photographer at any level
Hi Tony. Wasn't your formula predicting the 18PMP scoring Sigma 24-105mm on a 5D3 would rise by 14.5MP to give 32.5 PMP on a 5DsR? Seems your formula should be MPup/4 rather than MPup/2.