I’ve used the 18-400 for two years on Canon 80D and now 90D. There are two cons you didn’t mention. In Auto Focus the focus ring is locked out of manual operation and the zoom ring get stiff part way through it’s range. But other than otherwise it’s a great versatile lens. I shoot birds in flight, one of the most challenging photographic subjects for both photographers and their equipment. One both cameras the 18-400 works extremely well. The Auto Focus is fast, accurate and stays locked on. Especially the 80D. If you like close up work the 18-400 makes some really fine images. You need to be careful with focus, use a fast shutter speed and have a good light. It’s a good close up, but not a macro lens.
My camera is a Canon EOS 750D and I owned two lenses. On a holiday in South Africa I found was going on safari drives and if I wanted a particular shot I needed the lens I had left back in the camp. The next day I wanted the other lens and I thought, "The heck with this. I need a one for all lens". I asked another guest with a long lens if he found this preferable and he said definitely. I then decided to purchase a one for all and now have the Canon 18- 400. I find it's great to do a wide variety of shots across the focal length.
I also wish to mention that when I did film shooting years ago I had a great variety of beautiful lenses in my collection. The problem was they were 'screw thread' mount so couldn't use them when I went to a digital camera. It seemed a shame to sell them so I hunted down an adapter that has click mount on on one side for the camera body and screw thread on the outside. I'm now able to enjoy my old lenses, albeit on manual settings, but I'm getting some great photos on the Canon digital.
Great review! I just bought this lens today and spent the day with it on my EOS 90D and so far I absolutely love it!!! I would recommend it to anybody looking for that “all in one” lens. Also a big plus is my local camera shop was having a sale so I got it for $50 off NIB so I am a happy shooter. 😊
Glad to hear you are enjoying it! If you post any images on SM send me a message would love to see what you get with it! Twitter @focusedcamera and Insta @_focusedcamera
@@JContente yes you can definitely hear it. I think overall it is quiet. I tried to record the motor sound on my phone from 5 feet away and my phone could not pick up the sound any more than background noise. If you want this for skittish wildlife I would go to a camera shop that will let you put it on a camera and test it or maybe rent it? Another suggestion might be a camera club in your area where another member might have this lens.
@@FocusEdCamera thank you! Very fast response! I'm thinking of getting this lens for photography but would from time to time use it for video. I assume it gets caught on video right? I won't be a deal breaker just wanted to get to know the lens before getting it! Again thanks for the response!!!
@@JContente I think whether you hear it on video will depend on microphone type and location. If you use on camera mic you will pick it up but if you are using a lapel or USB mic that is away from camera by a few paces it may not pick up at all especially if it is cardioid type mic.
I just bought a mint condition EOS 40D from ebay, for my first camera. I want to buy one lens to use while developing my skills. This is the lens that I'll purchase. Thanks.
Nice! This is definitely a great lens for learning because it has a huge range of focal lengths for all kinds of photography types/genres. Would love to see some images as you learn, if you share any to SM let me know. My Twitter @focusedcamera and Insta @_focusedcamera Good luck!
I agree, it has decent sharpness. If someone is seeking image quality perfection this -- or any superzoom for that matter -- is not the lens you are look for, LOL. I very rarely use the full 400mm zoom, what do you mostly photograph? Do you use the 400mm frequently? If I used that focal length more, I would probably save up for the Canon EF 400mm f/5.6L USM. For my purposes, tho' I like the all-around one-lens usage this one has! I can pack light! Thanks for watching my video and taking time to comment. 😃
Hi! Thanks for watching my video. You are correct that the lens will mount on a full-frame, but since the lens is a Di II designed for crop sensor cameras, and since it is a third party lens (reverse engineered to fit Canon), I would not recommend using on a full frame Canon without carefully inspecting the back region to make sure the lens is not causing damage to the camera body. As you may already know, Canon EF-S lenses are not compatible with full-frames because the lens mechanisms extend too far back and can damage the mirror and interior of the full frame camera. Upon inspecting my lens, I do think the mechanisms on the back of the Tamron are a small enough profile that they probably would be okay, but I am still not going to risk it --- yet. Most of the reviewers I know use this lens only on crop-sensor cameras like the 80D, etc. because as you already said, if you do use it on full-frame (after making sure it isn't causing damage) you will get the crop/vignette effect since the lens covers part of the larger sensor in a full frame. Overall do you use this lens a lot and like it? I have used the heck out of mine! 😃
Moisture/weather sealing depends on the camera. Most of the newer models have some degree of resistance and not all weather treatments are equal. Olympus, Fuji are more known for the "toughness" of their cameras. The Canon 5DIII and IV, 6D, 6DII, 1DX II, 5DS R, R, 7DII, 70D, 80D, 90D and a few more in the Canon line have some weather resistance. I am not as familiar with Nikon but I think the Z7, Z50, D7500, D750, and D850 are as well (and there are most likely many other models). I didn't get into the details about steps that I take when packing for different types of weather, but typically I have a large ziploc bag in my camera gear so I can put that over the camera and most of the lens. Then only part of the lens might be exposed if I needed to keep shooting. Generally I retreat when rain of any kinds starts. But in the scenario where you have some kind of camera cover then the lens having some weather resistance is important as that part may still be a bit more exposed. As far as whether the 18-400mm is sharper than the Canon 75-300mm, it think it will depend on the version of the 75-300mm (there are at least 4 versions of this lens I believe). It would also depend on what focal length you use. Most zooms have pincushion and barrel distortions at their extreme ends so there are "sweet spots" of focal length and then there are sweet spots for aperture as well. Many many factors, of which I have not done extensive testing to be able to give you a definite answer. I would recommend doing side by side lens comparisons and reading the reviews on the following sites: DXOMark, Camera Decision, and Ken Rockwell, and if you know how to read MTF charts or want to learn, you could compare those (www.usa.canon.com/internet/portal/us/home/learn/education/topics/article/2019/april/Reading-and-Understanding-Lens-MTF-Charts). Some of the comparisons on these sites include actual images taken by different lenses so you can pixel peep. So, all that being said, I do have a 75-300 USM original version and the Tamron and if I were going to pack one of the lenses, I would take the Tamron and that decision has nothing to do with image quality differences (which I have not tested nor noticed in passing). The overall focal length range is better (I like having that wider angle option) and it doesn't weight much more (a few ounces?).
I rather wish to know for the Nikon D780, looking desperately for a lens that fits and works well. But so many people and so many different opinions cause conflicting messages. One claims it should be fine (including the official website) and a lot of youtubers claim it can not do that task (the cropping thing which makes it pointless for a full frame body). Please do help me out on this, I don't have the money to waste money on products that end up being a failure.
I will do a bit of research to be sure of my facts and then I will get back to you with info specifically for Nikon D780. I will have some answers for you in 24-48 hours.
This lens is listed as compatible with the Nikon D780 on Tamron's website. Here is the link to their compatibility checker: www.tamron.com/faq/products/checker.html HOWEVER, since it is a Di-II lens it will have a crop factor on a full frame camera. You would have to go into the settings and set the image area/lens to APS-C. The only full frame lens I see on Tamron's compatibility chart that would give you a large zoom range is the 28-300mm which is a Di (full frame design) lens here: www.tamron.jp/en/product/lenses/a010.html Now, that doesn't quite have the range of the 18-400mm and the 400mm on a crop actually is more like a 600mm so it will be a compromise -- you get the full frame lens but less reach. That also being said, Nikon does not guarantee third party lenses will work (any of them - ever) because they are only responsible for their own gear/lenses. A lens might work today from Tamron, but a future Nikon body or firmware update -- maybe not. If you can find a RENTAL location, and are still interested in a Tamron, I would rent it for a few days before investing/buying. Or purchase from a retailer that will allow returns without restocking fees if you want to try it without financial risk. Good luck!
Hi Thanks for the video. I bought the 18-400 for my Nikon D5600 and as much as it does work ok I do have a couple of Issues. the first is that when you zoom out it won't focus and I have to manually focus. the second is that for some reason it freezes my aperture and it wont open. I usually undo the lens and click it back in and this seems to help albeit temporary. I think I may get someone to have a look. Regards Phil
If it is still under warranty I would definitely contact the manufacturer. I had a Canon lens that would stop operating when I changed aperture and it was the aperture control module in the lens that was the issue. Unfortunately that lens is not under warranty any more. I would report the lens and serial number to Tamron either way. Good luck! I hope it is an inexpensive solve for you. Thanks for watching my video! 😃
I cringe when you pull the lens instead of using the zoom ring. I just bought this lens for my Canon 70D and it's an okay lens. Sometimes the images are soft with larger apertures. I had to do minor micro-adjustment focusing to get sharpness improvement.
Yeah, unfortunately without it connected to a camera it was very awkward to try to open and close it with the ring since there was nothing to twist against. I wouldn't normally do that or do that when it is on camera. Thanks for pointing that out. I figure some lenses don't have zoom rings so they twist or pull from the end anyway and that hopefully I didn't do any lasting damage. It's a very sturdy lens and so far no issues! Sounds like you already know how to fix front or back focusing issues with your lens, but if you need any resources for it, this is a great link: www.borrowlenses.com/blog/microadjustment-for-lens-and-camera-frontback-focusing-issues/ Thanks for taking the time to make a comment and for watching my video! 😊
You can use this lens on the R6 with the Adapter for EF lens to R body. You will have a cropped view - so at 50mm it will look more like 80mm etc but it will work and autofocus controls should still communicate. The Sigma 150-600 is another great lens but doesn’t have the range that “all around.” The Sigma is also waaaaay heavier. The Tamron fits in bag, is light, and is all one might need for so much. I still highly recommend it.
Thanks for viewing my video. I have used Sigma lenses, but not that particular one. Since I wasn't sure if you are planning to use it on Canon, Nikon or other camera body I was a bit limited on what I could find that might be helpful. One of my favorite sites to research lenses is DXO Mark they do comparisons of lenses and camera bodies, unfortunately they only tested that lens on Nikon -- but here's a link to the comparison I created between the Sigma 18-300 and the 70-300 Macro. You can edit the parameters and choose different lenses to compare -- it's a great site: www.dxomark.com/Lenses/Compare/Side-by-side/70-300mm-f-4-5.6-APO-DG-MACRO-Nikon-on-Nikon-D800E-versus-70-300mm-f-4-5.6-APO-DG-MACRO-Canon-on-Canon-EOS-5DS-R-versus-Sigma-18-300mm-F35-63-DC-MACRO-OS-HSM-C-Nikon-on-Nikon-D500__259_814_258_1009_1410_1061 Also, I did a cursory look for the MTF charts for this lens -- I was looking for Canon version since the other site only compared Nikon and found this from Sigma: www.sigma-global.com/en/lenses/cas/product/contemporary/c_18_300_35_63/data/ Resolution is better at 300mm but will be soft around the edges, however astigmatism will be worse at 300mm. The drawback to these charts is they only show the lens at its two extremes. Soooo, I found a really good review of the lens, also for the Nikon version, but their explanation of the lens' performance and the charts is very good: www.ephotozine.com/article/sigma-18-300mm-f-3-5-6-3-macro-os-hsm-c-lens-review-26618 Hopefully this info can help you make a decision! Good luck!
If you have an adapter like this one: www.bestbuy.com/site/canon-ef-eos-r-and-eos-rp-lens-mount-adapter/6298155.p?skuId=6298155 it should work with this lens. So should this one: fotodioxpro.com/collections/lens-mount-adapters/products/eos-crf-fsn (New from Fotodiox, so... it's off brand but I have had good luck with their products)
It isn’t always considered a con but aps-c is a smaller sensor size. This typically means that it is harder to get the blur/bokeh behind a subject compared to a full frame sensor among other things. Whenever you see a lens focal length like 50mm it refers to an angle of view when on full frame. A crop aps-c will have a narrower angle of view with that same lens (a crop factor typically about 1.5-1.6x) meaning that the 50mm behaves more like a 75-80mm. On longer focal lengths like like 200mm it means the effective focal length is closer to 300mm. This can make aps-c cameras a good option for long distance subjects like wildlife or sports - you get more “reach” with the lens. The website mmcalc.com (or their app) provides a basic calculator that will show you the effective focal lengths for a specific lens. There are depth of field calculators and simulators that can show you the effect of crop (apsc) cameras vs full frame and the resulting depth of field for different camera and lens combos. These are the main key differences. Most of the “better” lenses are designed for full frame cameras so that is another reason. Let me know if you need more explanation. Thanks for watching my video! 😃
I’ve used the 18-400 for two years on Canon 80D and now 90D. There are two cons you didn’t mention. In Auto Focus the focus ring is locked out of manual operation and the zoom ring get stiff part way through it’s range. But other than otherwise it’s a great versatile lens. I shoot birds in flight, one of the most challenging photographic subjects for both photographers and their equipment. One both cameras the 18-400 works extremely well. The Auto Focus is fast, accurate and stays locked on. Especially the 80D. If you like close up work the 18-400 makes some really fine images. You need to be careful with focus, use a fast shutter speed and have a good light. It’s a good close up, but not a macro lens.
My camera is a Canon EOS 750D and I owned two lenses. On a holiday in South Africa I found was going on safari drives and if I wanted a particular shot I needed the lens I had left back in the camp. The next day I wanted the other lens and I thought, "The heck with this. I need a one for all lens". I asked another guest with a long lens if he found this preferable and he said definitely. I then decided to purchase a one for all and now have the Canon 18- 400. I find it's great to do a wide variety of shots across the focal length.
I use this lens all the time. The more I use it, my other lenses collect dust. Best lens ever.
I also wish to mention that when I did film shooting years ago I had a great variety of beautiful lenses in my collection. The problem was they were 'screw thread' mount so couldn't use them when I went to a digital camera. It seemed a shame to sell them so I hunted down an adapter that has click mount on on one side for the camera body and screw thread on the outside. I'm now able to enjoy my old lenses, albeit on manual settings, but I'm getting some great photos on the Canon digital.
Great review! I just bought this lens today and spent the day with it on my EOS 90D and so far I absolutely love it!!! I would recommend it to anybody looking for that “all in one” lens. Also a big plus is my local camera shop was having a sale so I got it for $50 off NIB so I am a happy shooter. 😊
Glad to hear you are enjoying it! If you post any images on SM send me a message would love to see what you get with it! Twitter @focusedcamera and Insta @_focusedcamera
Is the auto focus loud? Can you hear it?
@@JContente yes you can definitely hear it. I think overall it is quiet. I tried to record the motor sound on my phone from 5 feet away and my phone could not pick up the sound any more than background noise. If you want this for skittish wildlife I would go to a camera shop that will let you put it on a camera and test it or maybe rent it? Another suggestion might be a camera club in your area where another member might have this lens.
@@FocusEdCamera thank you! Very fast response! I'm thinking of getting this lens for photography but would from time to time use it for video. I assume it gets caught on video right? I won't be a deal breaker just wanted to get to know the lens before getting it! Again thanks for the response!!!
@@JContente I think whether you hear it on video will depend on microphone type and location. If you use on camera mic you will pick it up but if you are using a lapel or USB mic that is away from camera by a few paces it may not pick up at all especially if it is cardioid type mic.
Perfect lens for Professional Battlefield Photographers ..people who simply cannot mess around with changing lenses
I just bought a mint condition EOS 40D from ebay, for my first camera. I want to buy one lens to use while developing my skills. This is the lens that I'll purchase. Thanks.
Nice! This is definitely a great lens for learning because it has a huge range of focal lengths for all kinds of photography types/genres. Would love to see some images as you learn, if you share any to SM let me know. My Twitter @focusedcamera and Insta @_focusedcamera Good luck!
Great video!
Glad you enjoyed it
I tried this lens, and there was noticeable distortion on the wide end. Overall, a great lens with decent sharpness even on the long end.
I agree, it has decent sharpness. If someone is seeking image quality perfection this -- or any superzoom for that matter -- is not the lens you are look for, LOL. I very rarely use the full 400mm zoom, what do you mostly photograph? Do you use the 400mm frequently? If I used that focal length more, I would probably save up for the Canon EF 400mm f/5.6L USM. For my purposes, tho' I like the all-around one-lens usage this one has! I can pack light! Thanks for watching my video and taking time to comment. 😃
You can use it on Canon full frame. I have it on my 6D. It works just fine, except for the vignette.
Hi! Thanks for watching my video. You are correct that the lens will mount on a full-frame, but since the lens is a Di II designed for crop sensor cameras, and since it is a third party lens (reverse engineered to fit Canon), I would not recommend using on a full frame Canon without carefully inspecting the back region to make sure the lens is not causing damage to the camera body. As you may already know, Canon EF-S lenses are not compatible with full-frames because the lens mechanisms extend too far back and can damage the mirror and interior of the full frame camera. Upon inspecting my lens, I do think the mechanisms on the back of the Tamron are a small enough profile that they probably would be okay, but I am still not going to risk it --- yet. Most of the reviewers I know use this lens only on crop-sensor cameras like the 80D, etc. because as you already said, if you do use it on full-frame (after making sure it isn't causing damage) you will get the crop/vignette effect since the lens covers part of the larger sensor in a full frame. Overall do you use this lens a lot and like it? I have used the heck out of mine! 😃
It's moisture resistant, but what about the camera? Will it produce significantly sharper images than the 70-300mm kit zoom?
Moisture/weather sealing depends on the camera. Most of the newer models have some degree of resistance and not all weather treatments are equal. Olympus, Fuji are more known for the "toughness" of their cameras. The Canon 5DIII and IV, 6D, 6DII, 1DX II, 5DS R, R, 7DII, 70D, 80D, 90D and a few more in the Canon line have some weather resistance. I am not as familiar with Nikon but I think the Z7, Z50, D7500, D750, and D850 are as well (and there are most likely many other models). I didn't get into the details about steps that I take when packing for different types of weather, but typically I have a large ziploc bag in my camera gear so I can put that over the camera and most of the lens. Then only part of the lens might be exposed if I needed to keep shooting. Generally I retreat when rain of any kinds starts. But in the scenario where you have some kind of camera cover then the lens having some weather resistance is important as that part may still be a bit more exposed. As far as whether the 18-400mm is sharper than the Canon 75-300mm, it think it will depend on the version of the 75-300mm (there are at least 4 versions of this lens I believe). It would also depend on what focal length you use. Most zooms have pincushion and barrel distortions at their extreme ends so there are "sweet spots" of focal length and then there are sweet spots for aperture as well. Many many factors, of which I have not done extensive testing to be able to give you a definite answer. I would recommend doing side by side lens comparisons and reading the reviews on the following sites: DXOMark, Camera Decision, and Ken Rockwell, and if you know how to read MTF charts or want to learn, you could compare those (www.usa.canon.com/internet/portal/us/home/learn/education/topics/article/2019/april/Reading-and-Understanding-Lens-MTF-Charts).
Some of the comparisons on these sites include actual images taken by different lenses so you can pixel peep. So, all that being said, I do have a 75-300 USM original version and the Tamron and if I were going to pack one of the lenses, I would take the Tamron and that decision has nothing to do with image quality differences (which I have not tested nor noticed in passing). The overall focal length range is better (I like having that wider angle option) and it doesn't weight much more (a few ounces?).
I rather wish to know for the Nikon D780, looking desperately for a lens that fits and works well. But so many people and so many different opinions cause conflicting messages. One claims it should be fine (including the official website) and a lot of youtubers claim it can not do that task (the cropping thing which makes it pointless for a full frame body). Please do help me out on this, I don't have the money to waste money on products that end up being a failure.
I will do a bit of research to be sure of my facts and then I will get back to you with info specifically for Nikon D780. I will have some answers for you in 24-48 hours.
This lens is listed as compatible with the Nikon D780 on Tamron's website. Here is the link to their compatibility checker: www.tamron.com/faq/products/checker.html HOWEVER, since it is a Di-II lens it will have a crop factor on a full frame camera. You would have to go into the settings and set the image area/lens to APS-C. The only full frame lens I see on Tamron's compatibility chart that would give you a large zoom range is the 28-300mm which is a Di (full frame design) lens here: www.tamron.jp/en/product/lenses/a010.html Now, that doesn't quite have the range of the 18-400mm and the 400mm on a crop actually is more like a 600mm so it will be a compromise -- you get the full frame lens but less reach. That also being said, Nikon does not guarantee third party lenses will work (any of them - ever) because they are only responsible for their own gear/lenses. A lens might work today from Tamron, but a future Nikon body or firmware update -- maybe not. If you can find a RENTAL location, and are still interested in a Tamron, I would rent it for a few days before investing/buying. Or purchase from a retailer that will allow returns without restocking fees if you want to try it without financial risk. Good luck!
Hi Thanks for the video. I bought the 18-400 for my Nikon D5600 and as much as it does work ok I do have a couple of Issues. the first is that when you zoom out it won't focus and I have to manually focus. the second is that for some reason it freezes my aperture and it wont open. I usually undo the lens and click it back in and this seems to help albeit temporary. I think I may get someone to have a look. Regards Phil
If it is still under warranty I would definitely contact the manufacturer. I had a Canon lens that would stop operating when I changed aperture and it was the aperture control module in the lens that was the issue. Unfortunately that lens is not under warranty any more. I would report the lens and serial number to Tamron either way. Good luck! I hope it is an inexpensive solve for you. Thanks for watching my video! 😃
@@FocusEdCamera hi thank you for replying I will follow up and see what they say. Thanks again
I cringe when you pull the lens instead of using the zoom ring. I just bought this lens for my Canon 70D and it's an okay lens. Sometimes the images are soft with larger apertures. I had to do minor micro-adjustment focusing to get sharpness improvement.
Yeah, unfortunately without it connected to a camera it was very awkward to try to open and close it with the ring since there was nothing to twist against. I wouldn't normally do that or do that when it is on camera. Thanks for pointing that out. I figure some lenses don't have zoom rings so they twist or pull from the end anyway and that hopefully I didn't do any lasting damage. It's a very sturdy lens and so far no issues! Sounds like you already know how to fix front or back focusing issues with your lens, but if you need any resources for it, this is a great link: www.borrowlenses.com/blog/microadjustment-for-lens-and-camera-frontback-focusing-issues/ Thanks for taking the time to make a comment and for watching my video! 😊
Do you know a lens what is for my camera? I have an ef mounth adaper. CANON R6. So full frame. but i like this range. for traveling
You can use this lens on the R6 with the Adapter for EF lens to R body. You will have a cropped view - so at 50mm it will look more like 80mm etc but it will work and autofocus controls should still communicate. The Sigma 150-600 is another great lens but doesn’t have the range that “all around.” The Sigma is also waaaaay heavier. The Tamron fits in bag, is light, and is all one might need for so much. I still highly recommend it.
Hi great video have you tried out the sigma 18-300mm macro lens and if so what did you think of it please.
Thanks for viewing my video. I have used Sigma lenses, but not that particular one. Since I wasn't sure if you are planning to use it on Canon, Nikon or other camera body I was a bit limited on what I could find that might be helpful. One of my favorite sites to research lenses is DXO Mark they do comparisons of lenses and camera bodies, unfortunately they only tested that lens on Nikon -- but here's a link to the comparison I created between the Sigma 18-300 and the 70-300 Macro. You can edit the parameters and choose different lenses to compare -- it's a great site: www.dxomark.com/Lenses/Compare/Side-by-side/70-300mm-f-4-5.6-APO-DG-MACRO-Nikon-on-Nikon-D800E-versus-70-300mm-f-4-5.6-APO-DG-MACRO-Canon-on-Canon-EOS-5DS-R-versus-Sigma-18-300mm-F35-63-DC-MACRO-OS-HSM-C-Nikon-on-Nikon-D500__259_814_258_1009_1410_1061 Also, I did a cursory look for the MTF charts for this lens -- I was looking for Canon version since the other site only compared Nikon and found this from Sigma: www.sigma-global.com/en/lenses/cas/product/contemporary/c_18_300_35_63/data/ Resolution is better at 300mm but will be soft around the edges, however astigmatism will be worse at 300mm. The drawback to these charts is they only show the lens at its two extremes. Soooo, I found a really good review of the lens, also for the Nikon version, but their explanation of the lens' performance and the charts is very good: www.ephotozine.com/article/sigma-18-300mm-f-3-5-6-3-macro-os-hsm-c-lens-review-26618 Hopefully this info can help you make a decision! Good luck!
நன்றி
Just bought a EOS R. I wont be able to use this lens with my full frame camera w. EF-RF adapter?
If you have an adapter like this one: www.bestbuy.com/site/canon-ef-eos-r-and-eos-rp-lens-mount-adapter/6298155.p?skuId=6298155 it should work with this lens. So should this one: fotodioxpro.com/collections/lens-mount-adapters/products/eos-crf-fsn (New from Fotodiox, so... it's off brand but I have had good luck with their products)
Why is aps-c a con?
It isn’t always considered a con but aps-c is a smaller sensor size. This typically means that it is harder to get the blur/bokeh behind a subject compared to a full frame sensor among other things. Whenever you see a lens focal length like 50mm it refers to an angle of view when on full frame. A crop aps-c will have a narrower angle of view with that same lens (a crop factor typically about 1.5-1.6x) meaning that the 50mm behaves more like a 75-80mm. On longer focal lengths like like 200mm it means the effective focal length is closer to 300mm. This can make aps-c cameras a good option for long distance subjects like wildlife or sports - you get more “reach” with the lens. The website mmcalc.com (or their app) provides a basic calculator that will show you the effective focal lengths for a specific lens. There are depth of field calculators and simulators that can show you the effect of crop (apsc) cameras vs full frame and the resulting depth of field for different camera and lens combos. These are the main key differences. Most of the “better” lenses are designed for full frame cameras so that is another reason. Let me know if you need more explanation. Thanks for watching my video! 😃