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stehei
29-Mar-2008, 12:23
Hello,

I have a question on perspective in portrait photography,
I've always been learned that it is not the lens, but the
distance to the subject that 'makes' perspective,

But now that I work on 8*10, is it possible that its the
format that changes perspective too?
and how does that change the '85mm on 35mm portrait lens' 'rule'?

Someone here to enlighten me?

Jim Noel
29-Mar-2008, 12:51
The equivalent of an 85 mm for 35 mm would be approximately 500 mm for 8x10.

Peter K
29-Mar-2008, 12:56
The distance to the subject makes perspective, but the subjective impression depends also from the size of the final image.

So the perspective of an 8x10 contact print taken with a 480mm lens looks like the same as an 8x10 print taken with an 85mm lens on 35mm film.

David A. Goldfarb
29-Mar-2008, 12:57
There is a good article by Ron Wisner about this subject, explaining why it is that as one goes up in format, the "portrait" focal length becomes shorter relative to the format, aside from practical considerations of bellows length and such. I think it originally appeared in _View Camera_ magazine and used to be on his website, but wasn't there last I checked.

For 8x10", a normal portrait lens is on the order of 14" or 360mm or maybe a bit longer. 14" was good enough for Karsh.

walter23
29-Mar-2008, 13:04
Distance to subject does determine perspective. Two lenses on two different formats with a similar field of view, at the same distance, will render roughly the same perspective and overall composition. Depth of field will be different, lesser in the case of the larger format.

As pointed out, people often use shorter lenses on the larger formats for practical reasons. The effect will be a "wider angle" or closer perspective.

Once
29-Mar-2008, 13:14
In my opinion you would be better off if you bought a good book about the LF photography rather than asking individual advice. View Camera Technique by Leslie Stroebel is very good and you would find all you need to know and then some in there. Enjoy the LF!

Sheldon N
29-Mar-2008, 13:42
Does anyone know if it is the LENS distance to subject or the FILM distance to subject that determines perspective?

I would guess that the lens (nodal point) would be the deciding factor, but was always curious. With the bigger formats, there's a fair bit of difference between the lens distance and the film distance.

stehei
29-Mar-2008, 13:45
thanks for the replies,
I checked some books, and looked on the net and on this
forum, but I indeed got mixed messages,
Thanks for the tip on the book

regards

stefan

jb7
29-Mar-2008, 13:50
There has been a thread (or more) about this before,
I can't remember if it was one I dug up myself, or if it was a recent one-

It makes sense that it is the entrance pupil that determines perspective,
at least for the in-focus areas-
but I know I'm just repeating someone much more knowledgeable...

Can't wait for the answers to this one now...

j

Peter K
29-Mar-2008, 14:05
Does anyone know if it is the LENS distance to subject or the FILM distance to subject that determines perspective?

I would guess that the lens (nodal point) would be the deciding factor, but was always curious. With the bigger formats, there's a fair bit of difference between the lens distance and the film distance.
It's the FILM distance. This is one reason to focus with the lens standard. With some cameras on optical bench there is also a fine focusing aid at the film standard but this will always change the imaging scale and so also the perspective.

Peter K

Ole Tjugen
29-Mar-2008, 15:03
No, perspective is determined by the position of the lens entrance pupil.

Focussing with the lens standard changes perspective but not scale; focussing with the film standard changes scale but not perspective.

Peter K
29-Mar-2008, 16:11
No, perspective is determined by the position of the lens entrance pupil.

Focussing with the lens standard changes perspective but not scale; focussing with the film standard changes scale but not perspective.
This is only true with the hypercentric perspective with a loupe. The telescope and the camera uses the entocentric perspective. So the most far subject looks smaller as the same subject not so far away.

The image formed by a lens on the film in a camera is a perspective projection of the scene viewed by the entrance pupil of the lens. But the perspective can be controlled in the camera by use of the various camera movements. The principle is the same for all movements of the back of the camera, also the distance from the subject.

Helen Bach
29-Mar-2008, 16:27
There has been a thread (or more) about this before,
I can't remember if it was one I dug up myself, or if it was a recent one-

It makes sense that it is the entrance pupil that determines perspective,
at least for the in-focus areas-

It's already been answered by Ole and Peter (with slightly different meanings of the word 'perspective') but it applies to the whole image, not just the in-focus areas. In fact that's why it is the entrance pupil and not the front nodal point.

Best,
Helen

audioexcels
29-Mar-2008, 16:52
I don't see why "any" lens that is not some super wide on an 8X10 cannot be considered a portrait lens. Bellows is there for macro work and can be used to make portrait type shots with shorter focal lengths than "classic/traditional" lengths used on 35mm. At the same time, I have shot portraits with 21mm lenses on 35mm, and would consider a 35-50mm lens as plenty long enough for portrait based work.

You can always crop out whatever you don't want from the final image to give it more rectangular type shape=portraiture to me, or you can even do 8X8 for total square format if you like the absolute square aka Hassy type of shot.

There's many ways of approaching it, though if you are absolutely dead set on one focal length, one shooting distance, bellows used at a specific distance, etc. etc. then you would be best shooting with a Fujinon 600C;)...

erie patsellis
29-Mar-2008, 17:09
Hmm, I was thinking 19" Artar, mostly because I have one sitting here. Just goes to show, ask 10 photographers opinions on something, you'll get 11 answers.


erie

Don Hutton
29-Mar-2008, 18:43
I don't see why "any" lens that is not some super wide on an 8X10 cannot be considered a portrait lens.It's because different focal lenghs render perspective in dramatically different ways. Some of these are less flattering than others. Do some reading - there is so much information available there's no reason to remain ignorant.

At the same time, I have shot portraits with 21mm lenses on 35mm, and would consider a 35-50mm lens as plenty long enough for portrait based work.If you like portraits of people with huge noses and tiny ears, perhaps a wide angle may be suitable - you'd be in the extreme minority with that sort of choice. Most photographers avoid wides because they increase the relative size of foreground subject matter which tend not to render subjects in a flattering way... It has nothing to do with having to crop or not crop.
There's many ways of approaching it, though if you are absolutely dead set on one focal length, one shooting distance, bellows used at a specific distance, etc. etc. then you would be best shooting with a Fujinon 600C;)...I've actually used the Fuji 600C lens for portraiture - I'd never recommend it - it's slow (so focus is pretty tough under studio conditions especially if you get a lot of bellows extension) and very sharp in an almost harsh way - very unflattering in general.

My current favorite portrait lens for 8x10 is the 305mm Kodak Portrait lens - cheap, fast, in an Ilex 5 shutter and has excellent oomph. It's probably a little shorter than I would prefer for portraiture on 8x10 (it's pretty much perfect on whole plate), but it's other features win the day for me.

stehei
30-Mar-2008, 01:38
ok, so there is no difference in the use of lens/distance just because it is 8*10 inch?
So a 50mm in 35mm for total shots, 70mm for shoulder shots, 85 for head shots.

I originally came to this question because I made a shoulder shot with a 12,5 inch wollensak which I expected to be less flattering in perspective than it turned out.
but that's just me, no difference in the fysics of the matter

gladly the wollensak is a convertible, so I have a 20 inch at hand too :) Needs a
lot of bellows!

thanks for all the info,

stefan