VERY interesting Video, maybe the most interesting thing i have seen for a while. I am photographing professionally for years but i never dived into the tech this deeply. Thank you for uploading Gary!
Excellent overview of the technical differences between A and E mount, it was food for thought. I must say; I am amazed over your set up with cameras and how you make it fluid and everything works switching between the camera views. I've learnt something today, thanks!
I think I asked you to address this a while back and you did a great job at explaining the origins of focus judder in AF-C mode for still shots. I thought I had a defective camera and went on the official Sony forum to ask. They never told me either way if this was normal or not. It would be great if Sony found a solution to this, but if it's inherent in the tech, maybe not.
Great explanation! I sent a link to this to a friend who is considering jumping from Nikon to E-mount. I'm letting him better understand what what he is getting into and what his options are.
Great explanation! Seeing it like this makes it a whole lot clearer then just reding about it. BTW i stil use your A99 book from time to time. Many thanks.
Fascinating. I really appreciate the way you demonstrate things. "Don't just tell me, show me!"
8 лет назад
Very nice video Gary, not that this problem actually effects me directly, but I am impressed by the thoroughness of your explanation. All I can say is that i subscribed!
Great info. I switched from Nikon and now I have 2 A6000 and 2 A7 cameras. I am a bit frustrated that the A7 does not have AF-A. I usually shoot static subjects but it is nice to have the option of AF-A if a subjects gets moving. Why didn't Sony include AF-A through a firmware update?
Excellent, informative video. I do not own a Sony camera but I do own 2 x Olympus EM1 mirrorless and a Nikon D500 so found this video very interesting. Thanks a lot.
Hi Gary, really great video. Luckily I am the owner of the A99II, but still: does your message also still applies when you "disconnect"the focus function from the shutter release button and assign it to another button (like the AF/MF one, as I normally do)?
Hi Gary, many thanks for your great explanation. I didn't know about this difference in AFC mode. One comment: PDAF is enabled in Nex-6 up to f6.3 and in A6000 up to f11, so using AFC with f22 or even higher, one relies on the CDAF...
12:18 forward, the claim that "any camera that is mirrorless" isn't true. As m4/3 cameras focus always aperture wide open, even on C-AF mode as on every focus frame (9fps or higher etc) the aperture is opened and closed back. There is as well the problem with some lenses like Panasonic 100-300mm that are not compatible for high framerates because the aperture isn't fast enough to be opened fully and then be closed by the chosen high framerate, and you get lower framerate with such lens.
Still a question! I somehow can't find the answer of the following question. Hope to get it here. I would like to take a running kid as an example. Would a mirror less, let's say the A6000 (worlds "fastest" auto focus) struggle to grab and continue focusing on a kid running towards me? Let's assume at f5.6 at a cloudy day and that I start focusing while the kid is already running and the distance is about 12 to 15 feeds? Thanks!
I think mirrorless will get better with focusing as the sensors evolve. For instance the A7s will probably do this a little better when the lens get stepped down and the sensitivity increases it has a four stop advantage over its A7 and A7R counterparts.
Your frustration with RUclips was my fault! I posted a remark but then thought better of it because I decided it was stupid on my part and deleted it after I had posted it. That's why you could no longer find it. My bad.... :-( You did a great job explaining the problem with continuous tracking in an E-Mount camera. I was just a little slow on the uptake. I watched the above video four times. It was not until I compared how my A77II worked compared to my A3000 when both cameras were in the continuous tracking mode, that the idea finally got through my several layers of bone and fat, when I looked into the A77II and watched the iris stop down at the moment the picture was taken. I then did the same thing with my A3000 and saw how the lens stays at what ever f-stop I set it to, even before I press the shutter. I understand it now! Sometime I just need to do things myself before I can understand them. Thank you for your patience with me.
You have the Live View Setting Effect set to off in the A7? Do you have any demonstrations about how the Sony mirrorless cameras focus differently depending on this setting?
+Harvey Louis As I mentioned in my blog post that accompanied this video, I tried small-f/stop focusing with Live View Setting set to both ON and OFF and there was no difference.
Gary do you have anything current (2018) on the LA-EA2, EA3 and EA4 Sony adapters that let A-mount glass work on E-mount Sony cameras? There have been firmware updates to let the EA3 work on some Sonys, but the EA3 lacks the screw drive for some reason. Any news up the AE interfacing and firmware would be appreciated.
Thank you for the explanation. However, I'm left with a quandary: I started shooting wildlife clips using my A99 II + Sigma 500ex + Kenko DG4 1.4, which is very stable (the weight alone is a major contributor) - but shooting in daylight, I cannot change the aperture, and I get over exposed clips habitually. I cannot switch the lens filter to a polarizer in the field (dust issues), and not really fast enough. Do you have a suggestion on how to solve such a problem - if solvable?
It is also fair to point out that a traditional dslr is no better at tracking when shooting video since it has to be stopped down the same as an e-mount. The discussion on tracking only applies when shooting stills. Personally I don't see this as a big issue because if I'm shooting a moving subject for stills, odds are I'm looking for a fast shutter speed and my lens is close to wide open. Perfect example is the one used int the video 'birds in flight'.
Hi Gary, thanks for this great explanation. I have one more question: How does the e-mount A7 behave if you put an a-mount lens using an LA-EA4 adapter? Would there be a difference when using the LA-EA3 adapter?
What do you think about setting the Live View Display to OFF? I still see the aperture close down, but does that help with auto-focus tracking? Edit: I just did some testing and I still see the aperture close down when focusing. Live View Display being set to OFF wouldn't help. This is why I'm buying an a99II. Low light focusing IMO will always be a struggle on E-Mount because it doesn't focus wide open.
I don't do any bird photography. Still your video is really helpful in explaining the focus characteristics of mirrorless cameras, I started my Photography career with a Nikon FE manual focus camera and remembering practicing and practicing to get fast setting the aperture, shutter speed and focus. My photo buddies and I really got quite good at it. Now that autofocus is the thing I guess we'll have to live with its limitations.
Yes, you could live with its limitations... OR you can show off your hard-earned skill and track those suckers manually "like we used to do in the old days!" and run circles around the guys with the latest whiz-bang technology. :-) (Just like an engineer who grew up using a slide rule can run circles around the young 'uns who can only do things with spreadsheets, or how a Jedi master can out-do an army of stormtroopers with real guns.)
In my opinion, this af-c "bug" is not because of that it's mirrorless, it's because it's.. well, like that. DSLRs focus while their mirror is flipped up and have their aperture opened while doing so. A mirrorless could also do that it's focusing wide open continuously than closing the aperture down only when a picture is taken. So it's more a design flaw rather than the nature of mirrorless cameras. Exposure the cam could simulate with changing electronic shutter speed, iso in the background just for preview. It's not like that while you AF-C with a DSLR you would see the same DOF as your image will have.
hi sir. i have this one question that has been bothering me since day 1..about the A-Mount and E-Mount sensor..why Sony still using a transluscent mirror in their A-mount system..why cant they incorporate the mirrorless sensor (without the transluscent mirror).what are the real advantage of the mirror actually. because i dont see any difference in terms of functionality...for example, the upcoming a68 is still using SLT, but from my understanding the AF function is similar with a6000 (4D focus)..unless i am missing something. please enlighten me...im using a6000 + LA-EA4 + 400mm Minolta for the record..
+Salleh Sheikh Ibrahim Now that they've finally perfected using on-sensor PDAF, I predict that the next A-mount body will not use a translucent mirror anymore. GF
We now know the a99 came differently, but actually a mirrorless a Mount makes no sense. You could easily built one with a detachable la EA 5 or something, with a good af system in it that transports af Motor friction and so on. I dont See why a camera couldnt work perfekt with both Mounts. If they want to
3:29 Whilst Polaroid did invent instant cameras the other 'inventions' listed aren't particularly substantial. Foldable optics have been a feature of telescopes almost since their inception - we even have a word for it... telescopic. And whilst they may have used folding optics on a camera, it is really an application of a simple concept. They also didn't invent flat batteries, batteries have existed in all kinds of form factors to suit their application. On any kind of production scale it makes no difference if the battery is a cube, or an exaggerated cuboid. And many products did, and do use their own integrated circuits. They, are cheaper to manufacture than discrete components, improve manufacturing reliability, and reduce the ease of reverse engineering. Also, f/stop is a measurement of flux, or luminous intensity. Aperture, or aperture size is a controllable parameter on a camera. In the same way, you don't open up the angle of a door. You open the hinge. Other than that the content of the video was interesting.
Very helpful and it most certainly has gave me food for thought for my next CAMERA. I don't much care for video anyway. This has me looking more closely at the D810.
Hi Gary, George here. I know this is very old video but after viewing some BIF content here on RUclips shot with A7... cameras I came back to view your video explaining why it is more difficult to achieve focus on moving objects in AF-C mode with E-mount versus A-mount. So, something must have changed in the latest E-mount cameras because now everyone is touting how they are going to E-mount for better tracking of moving subjects. For example Mark Smith msmithphotos.com/. Can you and will you explain please?
Hey, George! You're right - this video pre-dates the A9, where these technical challenges have been solved. I've even updated the video's description to reflect this. Thanks for pointing this out!
As others have said, this isn't a mirrorless design flaw, but rather the implementation used by Sony. They could have reproduced exactly the manner of working of a DSLR for still shots, but a different behaviour in video mode. However, possibly for other technical reasons, they have decided to use the same focus method in both scenarios, leading to the issue you have highlighted. Of course, one could argue that the problem you are showing is not so much AF in mirrorless, but rather AF in low light. That is certainly important, but I suspect that Sony have decided that the likelihood is a photographer will be using a larger aperture in such cases anyway.
+Gary Friedman Thanks for the reply, but I was referring to the overall tone of the piece. In your subtitle you say, "BUT the E-mount architecture still has an inherent disadvantage when it comes to tracking moving objects", and then in the video, "Some people felt it was imperative to add movies to cameras and that just made things miserable", followed by, "This should give you a really good idea of how much more difficult it is for any camera, if it’s mirrorless, to be able find focus while the f stop is very, very small". This implies that the design is fundementally flawed, but I maintain that the designers could have, if necessary, kept the same behaviour except for when using video. Indeed, it would make far more sense to have turned off the DoF preview facility (i.e. kept the lens wide open) for continuous focus. I can only repeat, there doesn't seem to be any obvious reason why it was done this way and it is certainly nothing to do with the fact cameras are mirrorless or even that they can do video. This is an implementation issue, NOT a mirrorless 'E-mount architecture' problem.
Кирил Анастасов I have to agree with this. I loved your explanation up until your conclusions. I am trying to envision a scenario where I would shoot in AF-C at f22 in low light conditions. f22 gives me substantial depth of field especially on a smaller sensor like the a6000, so I think I would be more prone to nail focus either manually using focus peaking or AF-S, and not worry too much about subject movement.
***** I totally I agree with you and I've read your comment in the blog. My comment is pointed at people saying that this is an issue with e-mount, which it is not. I also think that if this becomes an issue it can be fixed with software.
When inside the cameras were the autofocus motor and the aperture motor the cost of lenses was much lower. The lenses were just mechanical without complex electronics. They had fewer things to go wrong and were more reliable. After the revolutionary Canon EF mount lenses in 1987 everything started to move inside the lenses, the autofocus motor, the aperture motor, the stabilization motor or even the shutter in the case of exquisite Hasselblad lenses. Many modern lenses don't even have true mechanical manual focus and focus by wire. All of these changes in lenses have made camera bodies more reliable because they have fewer things to go wrong. In the case of mirrorless cameras there is no mirror mechanism and no mechanical shutter is even needed with many models. Camera manufacturers know that most experienced amateurs or professionals invest more on lenses than camera bodies. So they try to make lenses as complex as possible and raise the prices.
Gary Friedman Video shooting with digital photographic cameras is a new phenomenon. Most lenses in the market weren't constructed to be used for video. For me is odd that manufacturers promote more the video performance of their photographic cameras than the quality of photos. Only digital medium format cameras are focused mostly to photography than videography.
That's what I predicted in my blog post at friedmanarchives.blogspot.com/2015/07/baseball-with-rbs-really-bad-shadows.html#A-mount ; however if they had done that then only about 10% of the A-mount lenses would have autofocused properly. (Optics have to be designed a certain way in order for the on-sensor PDAF to work effectively.) So the mirror was needed in order to be completely backward compatible with all lenses.
No Gary, IMHO Sony capable of making Decent A Mount Mirrorless, No need translucent mirror when using A Lenses. _(just like pentax K01)_ I think they hold further development for future agenda, something BIG, example: *Curved Sensor Mirrorless A mount* _(Sony secret weapon to beats Canon at Sports Arena)_
The K-01 offers only contrast-detect AF, the lowest performing option (that is also easiest to implement and works with all lenses). The mirror IS necessary for high-performance AF with all older lenses.
Is an A99 or D800 or 5D MKii really expanding and contracting the iris 10 times a second when shooting bursts in AF-C mode? If not then all of this is irrelevant for sports tracking. If so, why not do the same thing on and A7 during the burst in AF-C mode?
What I also observe, (problem only in mode) AF-C on my A7r II : Focus will wobble / Judder / hunt even in very bright light (!), and so as soon as selecting aperture smaller than F8. F 8 is still ok. F 9, .., f11, 16 immediately becomes unusable, confirmed with 3 original Sony FE lenses (no more because i had no access to others jet) : a new FE (forgot what) zoom, FE 55mm and even G-Master 85mm ! BUT (!!!) : When I use the Metabones IV adapter for my AF Canon EF 85mm L f1.2 : No such problems at all ! I really hope others will help by corroborating these facts, or explain if and how this can be fixed. ( Once again : Issue is systematic and only in AF-C mode. )
I don't understand why if mounting for instance a Canon EF f/1.2 85mm L on a Metabones adapter, I can perfectly work, but with the G-master 85mm not. it's a disaster that Sony does not offer workaround solutions the photographer might set in preferences.There MUST be such remedy doable and it should be warned about clearly..
Very good, BUT! In birds in flight photography, standard operating procedure is to set your lens at wide-open or a very little stopped down (⅓-⅔ stop), and then set your ISO to achieve the desired fast shutter speed, e.g., 1/1600s and up. It would be a big mistake to waste all that precious light by shutting your lens down. Much better, if you have a lot of light, to use a lower ISO and/or a higher shutter speed. All this applies to any action photography such as sports, pets and grandkids!
So the lesson, make sure you have an ND filter to put on your lens when shooting film during sunny days so that the F-stop will stay wide enough open for auto focus to stay pretty darn good. To be fair, you need ND filters anyway.
Next book I buy from you is an actual book. I regret buying the digital book, its so hard to read and look at the references. :( But but but it was really well written.
This behaviour in E mount seems like a bug or not so well thought out design for sports photography. I guess this may be reason some people say A6000 tracks well and others strongly disagree. With this "bug" A6000 will perform best with 70-200/4 wide open or at f/5.6 unlike DSLR where people close to f/8 or f/11 to get more DoF and avoid focusing errors. I will give it a shot. So far A6000 seems to be miles ahead in tracking relative to A7.
+Kiril Karaatanasov and now that the a6300 is coming out in March 2016, it will blow away most things for focus and tracking with 425 AF points across almost the entire frame
+Stephen Soukup I have been disappointed by marketing hype on few occasions so I am not holding my breath when camera manufacturer claims to have discovered a new uber cool technology before it gets some real people using it
Why Sony slt cameras cant have af in video with bigger f stop than f/3.5? You said that they need to have a lot of light....but I cant have af with lenses with f stop bigger than 3.5. , for example , Sony 50mm 1.8....there is not logical explanation for this.
.I AM PISSED OFF BECAUSE SONY has abandoned the A Mount Lens, and the new Sony a99ll is an A Mount camera, it just happens to be the best camera in it's class.....The only lens maker who is still making A mount Lenses for Sony cameras is CARL ZEISS, THANKS TO THEM....IF SONY CONTINUES TO BETRAY THE A MOUNT USERS I WILL GO WITH CANON, NIKON IS IN FINANCIAL TROUBLE AND WHO KNOWS WHAT ELSE....CANON WILL NOT JUST ROLL OVER AND LET SONY BECOME #1......THE RIPPLES AGAINST SONY FOR THIS BEHAVIOR IS JUST STARTING TO SHOW........
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VERY interesting Video, maybe the most interesting thing i have seen for a while. I am photographing professionally for years but i never dived into the tech this deeply. Thank you for uploading Gary!
GREAT.... the oldscool guy teching the youngsters the new scool tech in a perfect way. This is why knowledge always is handy ;-)
Excellent overview of the technical differences between A and E mount, it was food for thought.
I must say; I am amazed over your set up with cameras and how you make it fluid and everything works switching between the camera views.
I've learnt something today, thanks!
This was fantastic. Very informative and to the point. Thank you!
I think I asked you to address this a while back and you did a great job at explaining the origins of focus judder in AF-C mode for still shots. I thought I had a defective camera and went on the official Sony forum to ask. They never told me either way if this was normal or not. It would be great if Sony found a solution to this, but if it's inherent in the tech, maybe not.
Great explanation! I sent a link to this to a friend who is considering jumping from Nikon to E-mount. I'm letting him better understand what what he is getting into and what his options are.
Great explanation! Seeing it like this makes it a whole lot clearer then just reding about it. BTW i stil use your A99 book from time to time. Many thanks.
Fascinating. I really appreciate the way you demonstrate things. "Don't just tell me, show me!"
Very nice video Gary, not that this problem actually effects me directly, but I am impressed by the thoroughness of your explanation. All I can say is that i subscribed!
Well done Gary and very helpful!
Thanks!
a very precise explanation on the subject ,thanks for taking pain in the making of this video ...
Excellent presentation, I love the way you use your gadgets and cameras to explain and inform us of how things work.
Thank you!
Dear sir,
Thank you for your sharing knowledge
Hi Gary thanks a lot for this video, was an eye opener for me
Great info. I switched from Nikon and now I have 2 A6000 and 2 A7 cameras. I am a bit frustrated that the A7 does not have AF-A. I usually shoot static subjects but it is nice to have the option of AF-A if a subjects gets moving. Why didn't Sony include AF-A through a firmware update?
This is a very good and informative video. Thank you very much Gary!
Excellent, informative video. I do not own a Sony camera but I do own 2 x Olympus EM1 mirrorless and a Nikon D500 so found this video very interesting. Thanks a lot.
Hi Gary, really great video. Luckily I am the owner of the A99II, but still: does your message also still applies when you "disconnect"the focus function from the shutter release button and assign it to another button (like the AF/MF one, as I normally do)?
Hi Gary, many thanks for your great explanation. I didn't know about this difference in AFC mode. One comment: PDAF is enabled in Nex-6 up to f6.3 and in A6000 up to f11, so using AFC with f22 or even higher, one relies on the CDAF...
12:18 forward, the claim that "any camera that is mirrorless" isn't true. As m4/3 cameras focus always aperture wide open, even on C-AF mode as on every focus frame (9fps or higher etc) the aperture is opened and closed back. There is as well the problem with some lenses like Panasonic 100-300mm that are not compatible for high framerates because the aperture isn't fast enough to be opened fully and then be closed by the chosen high framerate, and you get lower framerate with such lens.
Still a question! I somehow can't find the answer of the following question. Hope to get it here. I would like to take a running kid as an example. Would a mirror less, let's say the A6000 (worlds "fastest" auto focus) struggle to grab and continue focusing on a kid running towards me? Let's assume at f5.6 at a cloudy day and that I start focusing while the kid is already running and the distance is about 12 to 15 feeds? Thanks!
I think mirrorless will get better with focusing as the sensors evolve. For instance the A7s will probably do this a little better when the lens get stepped down and the sensitivity increases it has a four stop advantage over its A7 and A7R counterparts.
Your frustration with RUclips was my fault! I posted a remark but then thought better of it because I decided it was stupid on my part and deleted it after I had posted it. That's why you could no longer find it. My bad.... :-(
You did a great job explaining the problem with continuous tracking in an E-Mount camera. I was just a little slow on the uptake. I watched the above video four times. It was not until I compared how my A77II worked compared to my A3000 when both cameras were in the continuous tracking mode, that the idea finally got through my several layers of bone and fat, when I looked into the A77II and watched the iris stop down at the moment the picture was taken. I then did the same thing with my A3000 and saw how the lens stays at what ever f-stop I set it to, even before I press the shutter. I understand it now!
Sometime I just need to do things myself before I can understand them. Thank you for your patience with me.
You have the Live View Setting Effect set to off in the A7? Do you have any demonstrations about how the Sony mirrorless cameras focus differently depending on this setting?
+Harvey Louis As I mentioned in my blog post that accompanied this video, I tried small-f/stop focusing with Live View Setting set to both ON and OFF and there was no difference.
Gary Friedman Doesn't the A mount A77ii seems to address this autofocus problem with the translucent mirror?
+Martin Brossman The A77ii has more in common with traditional DSLRs than mirrorless cameras.
Nice demonstration Gary... thanks
Gary do you have anything current (2018) on the LA-EA2, EA3 and EA4 Sony adapters that let A-mount glass work on E-mount Sony cameras? There have been firmware updates to let the EA3 work on some Sonys, but the EA3 lacks the screw drive for some reason. Any news up the AE interfacing and firmware would be appreciated.
why does the image didn't darken when raising the f-stop 11:33 ...
+Eng. Fares It's on Auto ISO
Hi Gary,
I wonder would be Sony A 68 so quick using my Minolta Beercan?
The conclusion seems to point to the a mount having better tracking than e mount ? But I don't see the tracking for a mount in the video ??
Thank you for the explanation. However, I'm left with a quandary: I started shooting wildlife clips using my A99 II + Sigma 500ex + Kenko DG4 1.4, which is very stable (the weight alone is a major contributor) - but shooting in daylight, I cannot change the aperture, and I get over exposed clips habitually. I cannot switch the lens filter to a polarizer in the field (dust issues), and not really fast enough. Do you have a suggestion on how to solve such a problem - if solvable?
One question: What if you use spot focus on the A7?
Will that result in the same "hunting"?
Such a good teacher.
Thanks! Tell the world!
It is also fair to point out that a traditional dslr is no better at tracking when shooting video since it has to be stopped down the same as an e-mount. The discussion on tracking only applies when shooting stills. Personally I don't see this as a big issue because if I'm shooting a moving subject for stills, odds are I'm looking for a fast shutter speed and my lens is close to wide open. Perfect example is the one used int the video 'birds in flight'.
Hi Gary, thanks for this great explanation. I have one more question:
How does the e-mount A7 behave if you put an a-mount lens using an LA-EA4 adapter?
Would there be a difference when using the LA-EA3 adapter?
thanks for this fast answer
What do you think about setting the Live View Display to OFF? I still see the aperture close down, but does that help with auto-focus tracking?
Edit: I just did some testing and I still see the aperture close down when focusing. Live View Display being set to OFF wouldn't help. This is why I'm buying an a99II. Low light focusing IMO will always be a struggle on E-Mount because it doesn't focus wide open.
I don't do any bird photography. Still your video is really helpful in explaining the focus characteristics of mirrorless cameras, I started my Photography career with a Nikon FE manual focus camera and remembering practicing and practicing to get fast setting the aperture, shutter speed and focus. My photo buddies and I really got quite good at it. Now that autofocus is the thing I guess we'll have to live with its limitations.
Yes, you could live with its limitations... OR you can show off your hard-earned skill and track those suckers manually "like we used to do in the old days!" and run circles around the guys with the latest whiz-bang technology. :-) (Just like an engineer who grew up using a slide rule can run circles around the young 'uns who can only do things with spreadsheets, or how a Jedi master can out-do an army of stormtroopers with real guns.)
Veeeery interesting video. Thanks for making this.
Another outstanding video! You are my hero sir!
In my opinion, this af-c "bug" is not because of that it's mirrorless, it's because it's.. well, like that. DSLRs focus while their mirror is flipped up and have their aperture opened while doing so. A mirrorless could also do that it's focusing wide open continuously than closing the aperture down only when a picture is taken. So it's more a design flaw rather than the nature of mirrorless cameras. Exposure the cam could simulate with changing electronic shutter speed, iso in the background just for preview. It's not like that while you AF-C with a DSLR you would see the same DOF as your image will have.
Gary, what to say after absorbing all of this... I subscribed....
can you suggest me a full frame camera for the bigner plz
hi sir. i have this one question that has been bothering me since day 1..about the A-Mount and E-Mount sensor..why Sony still using a transluscent mirror in their A-mount system..why cant they incorporate the mirrorless sensor (without the transluscent mirror).what are the real advantage of the mirror actually. because i dont see any difference in terms of functionality...for example, the upcoming a68 is still using SLT, but from my understanding the AF function is similar with a6000 (4D focus)..unless i am missing something. please enlighten me...im using a6000 + LA-EA4 + 400mm Minolta for the record..
+Salleh Sheikh Ibrahim Now that they've finally perfected using on-sensor PDAF, I predict that the next A-mount body will not use a translucent mirror anymore. GF
We now know the a99 came differently, but actually a mirrorless a Mount makes no sense. You could easily built one with a detachable la EA 5 or something, with a good af system in it that transports af Motor friction and so on. I dont See why a camera couldnt work perfekt with both Mounts. If they want to
3:29 Whilst Polaroid did invent instant cameras the other 'inventions' listed aren't particularly substantial. Foldable optics have been a feature of telescopes almost since their inception - we even have a word for it... telescopic. And whilst they may have used folding optics on a camera, it is really an application of a simple concept. They also didn't invent flat batteries, batteries have existed in all kinds of form factors to suit their application. On any kind of production scale it makes no difference if the battery is a cube, or an exaggerated cuboid.
And many products did, and do use their own integrated circuits. They, are cheaper to manufacture than discrete components, improve manufacturing reliability, and reduce the ease of reverse engineering.
Also, f/stop is a measurement of flux, or luminous intensity. Aperture, or aperture size is a controllable parameter on a camera. In the same way, you don't open up the angle of a door. You open the hinge.
Other than that the content of the video was interesting.
thanks. just bought a old a7s, and was puzzled by this problem.
Very helpful and it most certainly has gave me food for thought for my next CAMERA. I don't much care for video anyway. This has me looking more closely at the D810.
Hi Gary,
George here. I know this is very old video but after viewing some BIF content here on RUclips shot with A7... cameras I came back to view your video explaining why it is more difficult to achieve focus on moving objects in AF-C mode with E-mount versus A-mount. So, something must have changed in the latest E-mount cameras because now everyone is touting how they are going to E-mount for better tracking of moving subjects. For example Mark Smith msmithphotos.com/. Can you and will you explain please?
Hey, George! You're right - this video pre-dates the A9, where these technical challenges have been solved. I've even updated the video's description to reflect this. Thanks for pointing this out!
You put a lot of effort into your videos. But this one I don't get.
How do DSLRs focus and how is the difference an advantage vs. mirrorless.
As others have said, this isn't a mirrorless design flaw, but rather the implementation used by Sony.
They could have reproduced exactly the manner of working of a DSLR for still shots, but a different behaviour in video mode. However, possibly for other technical reasons, they have decided to use the same focus method in both scenarios, leading to the issue you have highlighted.
Of course, one could argue that the problem you are showing is not so much AF in mirrorless, but rather AF in low light. That is certainly important, but I suspect that Sony have decided that the likelihood is a photographer will be using a larger aperture in such cases anyway.
+Gary Friedman
Thanks for the reply, but I was referring to the overall tone of the piece.
In your subtitle you say, "BUT the E-mount architecture still has an inherent disadvantage when it comes to tracking moving objects",
and then in the video, "Some people felt it was imperative to add movies to cameras and that just made things miserable",
followed by, "This should give you a really good idea of how much more difficult it is for any camera, if it’s mirrorless, to be able find focus while the f stop is very, very small".
This implies that the design is fundementally flawed, but I maintain that the designers could have, if necessary, kept the same behaviour except for when using video.
Indeed, it would make far more sense to have turned off the DoF preview facility (i.e. kept the lens wide open) for continuous focus.
I can only repeat, there doesn't seem to be any obvious reason why it was done this way and it is certainly nothing to do with the fact cameras are mirrorless or even that they can do video. This is an implementation issue, NOT a mirrorless 'E-mount architecture' problem.
Who shoots with continuous focus and f22 and wide angle lens, so this being a problem?
Кирил Анастасов I have to agree with this. I loved your explanation up until your conclusions. I am trying to envision a scenario where I would shoot in AF-C at f22 in low light conditions. f22 gives me substantial depth of field especially on a smaller sensor like the a6000, so I think I would be more prone to nail focus either manually using focus peaking or AF-S, and not worry too much about subject movement.
***** I totally I agree with you and I've read your comment in the blog. My comment is pointed at people saying that this is an issue with e-mount, which it is not. I also think that if this becomes an issue it can be fixed with software.
Thanks Gary. I appreciate the clarification. Excellent walkthrough.
When inside the cameras were the autofocus motor and the aperture motor the cost of lenses was much lower. The lenses were just mechanical without complex electronics. They had fewer things to go wrong and were more reliable. After the revolutionary Canon EF mount lenses in 1987 everything started to move inside the lenses, the autofocus motor, the aperture motor, the stabilization motor or even the shutter in the case of exquisite Hasselblad lenses. Many modern lenses don't even have true mechanical manual focus and focus by wire. All of these changes in lenses have made camera bodies more reliable because they have fewer things to go wrong. In the case of mirrorless cameras there is no mirror mechanism and no mechanical shutter is even needed with many models.
Camera manufacturers know that most experienced amateurs or professionals invest more on lenses than camera bodies. So they try to make lenses as complex as possible and raise the prices.
Gary Friedman Video shooting with digital photographic cameras is a new phenomenon. Most lenses in the market weren't constructed to be used for video. For me is odd that manufacturers promote more the video performance of their photographic cameras than the quality of photos. Only digital medium format cameras are focused mostly to photography than videography.
Any chance you can do an A6000 vs A7 focus tracking comparison? I believe the A6000 will do much better than Ax cameras.
+vorple its shoud as the a6000 (with its 11 fps) was meant for sports/action where as the a7 was meant for normal stuff like portraits and landscapes.
Very informative !! Good job!!
Sony should release A Mount Mirrorless..in Minolta Body Form & Size
That's what I predicted in my blog post at friedmanarchives.blogspot.com/2015/07/baseball-with-rbs-really-bad-shadows.html#A-mount ; however if they had done that then only about 10% of the A-mount lenses would have autofocused properly. (Optics have to be designed a certain way in order for the on-sensor PDAF to work effectively.) So the mirror was needed in order to be completely backward compatible with all lenses.
Gary Friedman
Wow, Gary.
Sharp Explanation ;)
No Gary, IMHO Sony capable of making Decent A Mount Mirrorless,
No need translucent mirror when using A Lenses.
_(just like pentax K01)_
I think they hold further development for future agenda, something BIG, example: *Curved Sensor Mirrorless A mount*
_(Sony secret weapon to beats Canon at Sports Arena)_
The K-01 offers only contrast-detect AF, the lowest performing option (that is also easiest to implement and works with all lenses). The mirror IS necessary for high-performance AF with all older lenses.
Gary, dont forget Sony has Dual Pixel patent,
almost similar like Canon.
So _maybe_ PDAF is possible?
Well done & thorough!
i got a sony a3000 and the a-mount adaper. )
Is an A99 or D800 or 5D MKii really expanding and contracting the iris 10 times a second when shooting bursts in AF-C mode? If not then all of this is irrelevant for sports tracking. If so, why not do the same thing on and A7 during the burst in AF-C mode?
***** Thanks!
What I also observe,
(problem only in mode) AF-C on my A7r II :
Focus will wobble / Judder / hunt even in very bright light (!),
and so as soon as selecting aperture smaller than F8.
F 8 is still ok. F 9, .., f11, 16 immediately becomes unusable,
confirmed with 3 original Sony FE lenses (no more because i had no access to others jet) :
a new FE (forgot what) zoom, FE 55mm and even G-Master 85mm !
BUT (!!!) : When I use the Metabones IV adapter for my AF Canon EF 85mm L f1.2 : No such problems at all !
I really hope others will help by corroborating these facts,
or explain if and how this can be fixed.
( Once again : Issue is systematic and only in AF-C mode. )
+Alain Rupp Yes, phase detect AF goes away at apertures of f/8 or smaller.
I don't understand why if mounting for instance a Canon EF f/1.2 85mm L on a Metabones adapter, I can perfectly work, but with the G-master 85mm not. it's a disaster that Sony does not offer workaround solutions the photographer might set in preferences.There MUST be such remedy doable and it should be warned about clearly..
Dud you a camera genius
Nice explanation
Thank you for the eye opener
Thanks from Germany.Bas.
Very good, BUT! In birds in flight photography, standard operating procedure is to set your lens at wide-open or a very little stopped down (⅓-⅔ stop), and then set your ISO to achieve the desired fast shutter speed, e.g., 1/1600s and up. It would be a big mistake to waste all that precious light by shutting your lens down. Much better, if you have a lot of light, to use a lower ISO and/or a higher shutter speed. All this applies to any action photography such as sports, pets and grandkids!
great video.
So the lesson, make sure you have an ND filter to put on your lens when shooting film during sunny days so that the F-stop will stay wide enough open for auto focus to stay pretty darn good.
To be fair, you need ND filters anyway.
very nice video
Great job Gary.
gary you are great :)
But why is a6000 faster than a99 and a77?
Thank you!
oops, meant Dr Edwin Land, was an american giant - scientific researcher,inventor,engineer,entrepreneur
Next book I buy from you is an actual book. I regret buying the digital book, its so hard to read and look at the references. :( But but but it was really well written.
***** cool! I'll have to do that than eventually. I got the book on A7. :)
This behaviour in E mount seems like a bug or not so well thought out design for sports photography. I guess this may be reason some people say A6000 tracks well and others strongly disagree. With this "bug" A6000 will perform best with 70-200/4 wide open or at f/5.6 unlike DSLR where people close to f/8 or f/11 to get more DoF and avoid focusing errors.
I will give it a shot. So far A6000 seems to be miles ahead in tracking relative to A7.
+Kiril Karaatanasov and now that the a6300 is coming out in March 2016, it will blow away most things for focus and tracking with 425 AF points across almost the entire frame
+Stephen Soukup I have been disappointed by marketing hype on few occasions so I am not holding my breath when camera manufacturer claims to have discovered a new uber cool technology before it gets some real people using it
+Kiril Karaatanasov I tried it myself at Samys in West LA 2 weeks ago at the Sony event. it is super fast at AF acquisition. Much faster than my a6000
Did your a Genius
Why Sony slt cameras cant have af in video with bigger f stop than f/3.5? You said that they need to have a lot of light....but I cant have af with lenses with f stop bigger than 3.5. , for example , Sony 50mm 1.8....there is not logical explanation for this.
i corrected my question, i think!
Great!
very nice, take care dear you are breathing differently. or you can say it's short of breath.
I got the Polaroid when I was a kid...
Broke it in next to no time... :(
Thanks :)!!
you are awesome
professor Land was a american . giant, engineer, entrepreneur. missed.
Holy mouth breathing Batman.
.I AM PISSED OFF BECAUSE SONY has abandoned the A Mount Lens, and the new Sony a99ll is an A Mount camera, it just happens to be the best camera in it's class.....The only lens maker who is still making A mount Lenses for Sony cameras is CARL ZEISS, THANKS TO THEM....IF SONY CONTINUES TO BETRAY THE A MOUNT USERS I WILL GO WITH CANON, NIKON IS IN FINANCIAL TROUBLE AND WHO KNOWS WHAT ELSE....CANON WILL NOT JUST ROLL OVER AND LET SONY BECOME #1......THE RIPPLES AGAINST SONY FOR THIS BEHAVIOR IS JUST STARTING TO SHOW........
Sony have not abandoned the A mount.