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I am using a Nikon 50mm 1.8D, but with an APS-C on a D7200, it gives me 75mm focal length. It's as sharp as a $700 85mm lens, and I paid $135 brand new for it.

I am currently using this setup for beauty shots (I don't have the funds for a more elaborate lens at the moment) and I have found that right when I get close enough for headshots, distorotion starts.

I know lens correction can be useful to correct this, but I am wondering how good it is. So, in this situation, would correcting the shot with Lens Correction in PS/LR result in a good image? Or would it really not stack up with a 105mm lens?

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You might be confusing "distortion" with "perspective". Remember, 50mm lens stays 50mm lens on D7200, just the field of view changes. When shooting too close (I think about ~0.5-1m) you might see that 50mm starts acting "wide". That means, that nose get bigger, ears get farther away from the nose and other perks of wide-angle lenses.

Rule of thumb for portraits that I use is to be ~2m away from target and use longer lens for tighter shots.

You use d7200 which allows you shooting with very nice and extremely cheap lenses of the past, maybe you'll find 35-105mm f/3.5-4.5 useful ($100 or less on US ebay)

More importantly, you should just try and see difference between corrected and non-corrected images and pick what suits you. Only you can judge what is better image.

  • Ah, okay. Got it. There is just the 50mm on a crop part that I am missing something. Will say a 35mm lens on a full frame have the same perspective and lens distortion as the same 35mm on a crop (but what will appear on the crop image will only be the central defects of the lens)? How does this transfer to portraiture? Would this mean that to avoid say the defects of a 60mm (90mm equivalence), you would have to get a 75mm (but it would be a 113mm equivalence, which might not what is needed)? – samseva Jan 18 '17 at 4:32
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    Yes, crop and perspective are different things. Unfortunately, I don't think there are rules for portraits. You should try and see for yourself. I shoot with FX camera and 200mm lens for tight faces, 70-120mm for face with shoulders. I think 70-100mm focal length will be OK for DX face portraits. I only shot with 18-55mm on DX, no tight face pictures. – Oct18 is day of silence on SE Jan 18 '17 at 8:32
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More likely you are seeing an error as to perspective. If you work in too close, the nose reproduces too large and the ears too small. Such facial modifications will be seen by the client even if they are minuscule. This is because the client has a mental picture of what he/she looks like and this is derived from the dressing mirror. Your task is to select a camera to subject distance that will deliver this mind’s eye viewpoint.

First – most pictures need not be correct as to perspective but portraiture is an exception. This is not truly a focal length thing; this is a camera to subject thing. When we compose we abhor leaving space around the portrait subject. What is needed is a moderate telephoto, a lash-up that delivers just enough magnification that we are forced to back up. If we can bring ourselves to just back up, a “normal” lens will do.

The focal length of choice is one that is about 2X thru 2 ½ X of “normal”. Now “normal” is a focal length about equal to the diagonal measure of the format. The APS-C (Advanced Photo System – Classic format) measures 16mm height by 24mm length and the diagonal of this rectangle is 30mm. Now “normal” for this size is a lens that delivers about a 45° field of view; camera held horizontal – that’s 30mm. Using the rule-of-thumb the suggested portrait focal lent is 30 X 2 thru 30 X 2.5 = 60mm thru 75mm. We are talking actual focal length, not equivalent. OK – you have a 50mm, I say that’s close enough. All you need do is force yourself to step back a foot or two.

Now comes the basis; nobody said this stuff is easy! A 50mm lens is mounted. An 8x10 inch print is made. The magnification to make the 8 X 10 from the APS-C is 12X. In other words, the 8X10 is the frame magnified 12 times. The viewing distance to visualize this image with correct perspective is focal length X magnification. Thus the ideal viewing distance if a 50mm lens is mounted is 50 X 12 = 600mm = 2 feet. Now beauty shots are placed on the wall or mantel and typically viewed from 1000mm (3 feet). Suppose you mounted a 75mm and made an 8X10. What is the viewing distance? Answer 75 X 12 = 900mm or about 1 yard. See how that works. This may be controversial stuff to some, but this is the basis of making images with correct perspective.

I suggest you don’t need to change lenses, just step back, this will yield a slightly smaller head size. You will need to increase the magnification slightly, say from 12X to 18X when you make the final print. That lash-up is 50 X 18 = 900mm = about 1 yard. That’s the secret. Now watch the other posters pounce on me!. Picked this up years ago. I was an instructor at the Professional Photographers School for continuing education. My subject was color print and process. I often help out as a gaff when the Master Portrait gurus taught -- some rubbed off.

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