100mm too long for portraits on a crop body?

scottduffy

scottduffy

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Hi folks,

I was wondering if any of you had any thoughts on whether a 100mm lens was too long on a crop body for portraits?

I've used canon 85mm lenses in the past but was never blown away by the image quality even though it's often highly spoken of and thought I'd try the 100mm f2 or either of the macro lenses to see if they had better image quality. I haven't bought a body yet but the lens might help me decide whether to go full frame or crop.
 
Depends how far away you stand! On a crop body I would say yes it's too long
 
Is it studio work?
 
Might be ok for outdoors if you can get far enough back to compose how you would like, I doubt you would have much use for it indoors though
 
In 35mm (full frame) days 75-85mm was considered to be the perfect focal length for portraits - just that slight compression of perspective. If you want to apply the same to a cropped sensor then, ideally, that would be around 50mm... however, that doesn't introduce the same 'compression' so, it's a tricky one to make any recommendations on.

50mm does it for me although 85mm and stand back a bit also works!
 
I've used 135mm on APS-C for head and shoulders portraits, it works well but you are a good distance away from the subject and engagement is tricky - can come in handy though if you have the room and want/need to restrict the FOV of the background (which was why I wanted to use it).

With so many home studios and even studios for hire being squeezed into ever smaller spaces it's likely to be the room dimensions that define the focal length. There's a "commercial" studio available for hire just round the corner. I went to an open evening and managed not to laugh out load until I left the building. But only just. I reckon a 50mm would have been pushing it on APS-C for head and shoulder length portrait work, and you'd have sub-optimal background separation and your back against the wall at that.
 
Mark twiglet said:
Is it studio work?
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Probably some of it will be but not solely for use in a studio. I will be using it at college in the studio but I was thinking more outside when I'm using it for portraits of my son.

I should have been clearer actually what I meant is will it compress the features too much so that it's an unflattering portrait.
 
Tdotcom said:
I use the 60mm macro on my crop camera. .its my go to lens for pretty much everything tbh :)
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I'm used to own the 60mm macro myself and really liked it. I was maybe going to purchase the 17-55 again and the 60mm is too close to that focal length for me. That's one of the reasons I was considering the 100mm.

I suppose I could always try them in college and see which one if any issues prefer. It's just that I can't do that till September.
 
I don't think that there is a "too long" or "too short" for portraits....it really depends on the effects that you're looking for and how comfortable the subject (victim in my case) is facing the camera. 50mm is fine for a born poser but I frequently use 200mm (on full frame) for those who are a little more self conscious.

Bob
 
chuckles said:
In 35mm (full frame) days 75-85mm was considered to be the perfect focal length for portraits - just that slight compression of perspective. If you want to apply the same to a cropped sensor then, ideally, that would be around 50mm... however, that doesn't introduce the same 'compression' so, it's a tricky one to make any recommendations on.

50mm does it for me although 85mm and stand back a bit also works!
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It should do shouldn't it? The compression/look is surely a function of camera to subject and subject to background distance so assuming that everything is in the same place (camera, subject, background) and the framing is the same MFT / APS-C / FF should give the same "compression" if you take account of the crop factor. Unless the smaller formats can't match the aperture setting/DoF and if not that'll be a difference between the shots but the actual compression should, I think :D be the same.

And the original question...

If you want to use 100mm for portraits on a smaller format system you may have to back up a bit so take a megaphone so that you can talk to your subject, or just use mobile phones :D
 
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woof woof said:
It should do shouldn't it? The compression/look is surely a function of camera to subject and subject to background distance so assuming that everything is in the same place (camera, subject, background) and the framing is the same MFT / APS-C / FF should give the same "compression" if you take account of the crop factor. Unless the smaller formats can't match the aperture setting/DoF and if not that'll be a difference between the shots but the actual compression should, I think :D be the same.

And the original question...

If you want to use 100mm for portraits on a smaller format system you may have to back up a bit so take a megaphone so that you can talk to your subject, or just use mobile phones :D
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compression is mostly todo with the focal length, for most people a longer focal length is more flattering, it maybe possible to "correct" say a m43 lens to give the perspective distortion of what its ment too, but i dont know if they do. but thats one of the reasons why medium and large format look better (all things being equal), is because they use a long focal length lens for just a normal angle
 
Compression is surely mostly to do with focal length because it decides the framing and / or the camera to subject and background distance.

If we use a longer lens and move further away the foreground subject may look a little smaller relative to the background whereas if we use a shorter lens and move closer the foreground elements may look larger relative to the background.

So, if we're talking about what I think we're talking about and it's perspective/flattening/compression... as in the size of the subject relative to the size of the background... then MFT = APS-C = FF other than DoF and 25mm MFT would = 35mm APS-C would = 50mm FF assuming that we stand in the same place and shoot the same subject against the same background and nothing moves.

Also, if everyone stands in exactly the same place and the 25/35/50mm lens falls off the camera and is replaced by a much wider one... we could crop the final image and get the same perspective/flattening/compression. Unless I've gone mad or we're talking about completely different things.
 
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theres a couple of different things

http://www.bing.com/images/search?q=portrait+at+different+focal+lengths&FORM=HDRSC2

but objects look different at different focal lengths, its more noticeable on the edge of frame, but thats the point im making, a longer focal length is slimming and reduces big noses etc

so a face at say 12mm is going to look alot different at say 85mm, and thats inherient to the way the lens renders. so "equivilency" can get you a similer looking picture with dof etc, but you will probably lose that more flattering focal length and its properties
using just the center of lens like crop cameras do itll be less bad, but still... :)
 
pingu666 said:
theres a couple of different things

http://www.bing.com/images/search?q=portrait+at+different+focal+lengths&FORM=HDRSC2

but objects look different at different focal lengths, its more noticeable on the edge of frame, but thats the point im making, a longer focal length is slimming and reduces big noses etc

so a face at say 12mm is going to look alot different at say 85mm, and thats inherient to the way the lens renders. so "equivilency" can get you a similer looking picture with dof etc, but you will probably lose that more flattering focal length and its properties
using just the center of lens like crop cameras do itll be less bad, but still... :)
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Noop. I still don't see what you're getting at :D Perspective and how the lens renders are normally meant to be different things.

Perspective is normally... compression, the size of stuff in the frame relative to each other etc, stuff like that... and rendering is normally bokeh, contrast and the like.

A 12mm lens could make the cutest little nose look like a whopper if you fill the frame with the face and the reason for this is that with the 12mm lens you'll have to get very close indeed but if you back off to 85mm distance and then shoot with the 12mm lens and crop the image the perspective will be the same as if you'd shot with the 85mm. Perspective/flattening/compression is the same with any lens but the distance you move away makes a difference.

I've just done this quick little test. The 1st image is MFT and 25mm, the 2nd is FF and 50mm and the 3rd is FF with 24mm but cropped to give FF 50mm FoV. There will be slight framing differences as I just sat there picking up cameras and lenses but you should be able to see that allowing for the small differences in my shifting position as I picked up cameras and lenses the DVD case in the foreground and the stuff behind it maintain the same relationships. The perspective is the same.







If I'd fitted a 135mm lens to get the foreground DVD the same size in the frame I'd have to back off more than I have room to do and in the final image the background things will look larger... the image will look flatter... you wont be able to see the turntable with the stack of DVD's on the top or at least you wont see as much of it but this isn't because I've used a longer lens it's because I've backed off.
 
If you were to try the same with a face you would notice the cute little nose turning into a whopper but there would be no ears! The lens cant "see" them. Move farther back with a longer lens, the more likely you are to record the ears and the nose becomes cute :)

Moving even further back and even longer lenses the "field" is flatter which leads to telephoto foreshortening or what looks like compression.
 
Canon Bob said:
I don't think that there is a "too long" or "too short" for portraits....it really depends on the effects that you're looking for and how comfortable the subject (victim in my case) is facing the camera. 50mm is fine for a born poser but I frequently use 200mm (on full frame) for those who are a little more self conscious.

Bob
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That's a good point. I never thought that maybe the subject would feel more comfortable with me a bit further out of their personal space.
 
It's where you stand in relation to the subject that changes perspective.

Changing the lens may force you to move back or forward to get the framing you want, but it isn't the lens changing perspective.
 
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