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12-22-2014, 06:08 PM   #16
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After browsing through the comments..

My preferred lens for FF was 85 to 105, but what works for me on APS-c is 70mm. Trying to do this with equivalents is pointless. Work with each format, choose the desired focal length from experience with that format. Using equivalence tables is pretty much a waste of time. You can use them for rough guidelines, but there's no substituting working with the cameras and lenses involved.

And the example is that 50mm on APS-c is equivalent to 70-80 mm on FF. Except a 70-80mm is a nice lens for portraits on FF. I've never found 50mm to be the equivalent on APS-c. Just one more reason why equivalence tables aren't worth the paper they're written on. Oh, and never use 35mm or less for portraits on any format, unless you plan to have the person a very small part of the frame. Doing a 35 mm portrait from close in is just bad photography.

It's odd, but I could probably happily use my SIgma 70 macro for portraits on both APS-c and FF. I'm sure the 77 is the same.


Last edited by normhead; 12-22-2014 at 06:13 PM.
12-22-2014, 08:42 PM   #17
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A lens with a short focal length can give a distorted view of the subject. Items slightly in front or behind the subject can be disproportionate. a longer focal length helps correct this. It also gives a better depth of field. The drawback is you have to get further away from your subject in order to get a similar framing of the subject. You have to balance all factors in order to choose the proper lens. My reference to 135mm lens, was based on those parameters. It was also recommended by every professional photographer I talked to in my area. This was approximately 40 years ago. unfortunately all of these photographers are either retired to unknown whereabouts or deceased. find something that works for you, and use it.
12-23-2014, 06:32 AM   #18
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I could be completely wrong, but from my understanding, a crop sensor behaves like a cropped fullframe sensor. Your 50mm Will act the same in terms of distortion or compression on a fullframe sensor as a crop sensor. The only difference is that the crop sensor captures a 1.5 or 1.6 (cant really remember) smaller part of the scene. Hope that explanes it for ya . PS. English is not my first language, so i am sorry, if something didnt make complete sence...
12-23-2014, 07:08 AM - 1 Like   #19
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QuoteOriginally posted by KidWithACamera Quote
I could be completely wrong, but from my understanding, a crop sensor behaves like a cropped full frame sensor. Your 50mm Will act the same in terms of distortion or compression on a fullframe sensor as a crop sensor. The only difference is that the crop sensor captures a 1.5 or 1.6 (cant really remember) smaller part of the scene. Hope that explanes it for ya . PS. English is not my first language, so i am sorry, if something didn't make complete sense...
Thinking that way is a complete waste of time. You can capture exactly the same scene with an APS-c sensor you do with a Full Frame sensor 90% of the time. There's no shortcut... you have to learn each format as if it were starting over from scratch. And within each format, you have to find the lenses you like. There's no magical free lunch where FF is like APS-c only bigger. In fact comparing a Canon 6D with a K-3, in terms of pixels, the K-3 is bigger. In digital, what else matters in terms of size, but the number of pixels and lw/ph?

You can capture exactly the same image with an FF if you have it set up, but you'd need a 600mm lens instead of a 400, and you'd have shallower depth of field for the same ƒ-stop. In other words you'd have to go to ƒ8 instead of ƒ5.6 with the equivalent loss of shutter speed.



On an image like this you'd need 24mm on a FF instead of 16mm, but you get pretty much the same image. That's the situation for 90% of the images ever taken.


There are instances in the wide end where the FF image may look better, but lets not get carried away. 90% of what you can do on an FF camera you can replicate on APS-c. The last 10%, it's quite possible you never want to go there anyway. 10% of what you can do on APS-c you can't do on FF, so it's a trade off, not an advantage in the big picture. You just need to know where your shooting preference are.


Last edited by normhead; 12-23-2014 at 08:16 AM.
12-23-2014, 07:40 AM   #20
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QuoteOriginally posted by KidWithACamera Quote
I could be completely wrong, but from my understanding, a crop sensor behaves like a cropped fullframe sensor. Your 50mm Will act the same in terms of distortion or compression on a fullframe sensor as a crop sensor. The only difference is that the crop sensor captures a 1.5 or 1.6 (cant really remember) smaller part of the scene. Hope that explanes it for ya . PS. English is not my first language, so i am sorry, if something didnt make complete sence...
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