Who can identify the focal length that was used?

As the subject line says.


Copyright assumed to belong to the Chicago Sun-Times.

I've tried to find the cover and copyright notice of the photographer on the newspaper's site, but was not successful. So, for editorial usage only!

Now, looking at the perspective distortion, I'd assume a 35-50mm on a full frame 24x36mm sensor array, or equivalent. The DoF looks a bit too funky, so Photoshop might be involved.

BTW, the camera standpoint above the eye-level isn't too flattering either.

Anybody else have a guess?

Bart

MF, 80mm

My guess is, MF, 80 mm or something like that.

Hi, Bart,

Bart_van_der_Wolf said:

Now, looking at the perspective distortion, I'd assume a 35-50mm on a full frame 24x36mm sensor array, or equivalent. The DoF looks a bit too funky, so Photoshop might be involved.

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a. You are probably not referring to perspective distortion (an ill-defined, if not wholly meaningless, notion), but rather just the impact of perspective.

b. The impact of perspective does not depend on focal length but rather only on the location of the camera (most notably for our purposes, the distance from the camera to the subject*). We could perhaps make an estimate of that by examination of the facial features.

* To be precise, the distance from the entrance pupil of the lens to the subject.

c. Having done that, making a determination of the focal length involved would require not only knowledge of the format size but as well knowledge of how the original image had been cropped (and, to be precise, the exact head size of the subject).

Doug_Kerr said:

a. You are probably not referring to perspective distortion (an ill-defined, if not wholly meaningless, notion), but rather just the impact of perspective.

b. The impact of perspective does not depend on focal length but rather only on the location of the camera (most notably for our purposes, the distance from the camera to the subject*). We could perhaps make an estimate of that by examination of the facial features.

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Hi Doug,

I'm referring to two things at the same time.

1. The perspective due to distance of the lens' entry pupil to the subject.
2. The distortion due to the 'inappropriate' viewing distance of the image. One gets a distorted view of the image/scene if not viewed at a distance (magnification and angle of view) proportional to the focal length. IOW when the image is magnified to 10x sensor array size, it should be viewed at 10x focal length distance for the same perspective as the lens saw, if we want to get a proper view. Looking at it from a different distance will create a sense of distortion (wide angle effect like in this case, or telephoto compression).

c. Having done that, making a determination of the focal length involved would require not only knowledge of the format size but as well knowledge of how the original image had been cropped (and, to be precise, the exact head size of the subject).

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With my reference to full frame I also meant uncropped, but thanks for specifying it in more accurate wordings.

So, with that out of the way, any guess? Guessing is fine, afterall we're in the Layback Cafe.

Bart

would probably be easy to get such thin DOF with a wide/normal lens on large format, or maybe even medium format, and probably on 35mm with one of the f1.2 lenses. It does look as if it was not taken with a longer more common 'portrait length' lens, but rather a normal lens, or maybe ever a slightly wider lens.

I've seen several portraits of him that look like they were taken with a mild-wide or normal lens, I'm not sure the reasoning behind that, maybe they are wanting to exaggerate his features a bit from a more classic portrait? Make the nose a bit larger and the ears a bit smaller?

Hi, Bart,

Bart_van_der_Wolf said:

Hi Doug,

I'm referring to two things at the same time.

1. The perspective due to distance of the lens' entry pupil to the subject.
2. The distortion due to the 'inappropriate' viewing distance of the image. One gets a distorted view of the image/scene if not viewed at a distance (magnification and angle of view) proportional to the focal length.

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Oh, of course, and I have to give greater appreciation to the phrase "perspective distortion" because of that notion (which I've been sort of ignoring in my quest to stamp out the inappropriate meaning of "perspective distortion").

IOW when the image is magnified to 10x sensor array size, it should be viewed at 10x focal length distance for the same perspective as the lens saw, if we want to get a proper view.

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Indeed

With my reference to full frame I also meant uncropped, but thanks for specifying it in more accurate wordings.[/quote]

No, I'm delighted to see you use the term that way (as I do), but I guess I thought you were using it the other (repulsive) way and thus didn't realize that I had your thoughts as to that parameter!

Best regards,

Doug

Looks like an ordinary 18" lens at about f11 on 8X10 format to me. I would have used a Petzval myself, but he didn't ask me.

Looks like a fake DOF (PS) to me… but that's not answering Bart's question!

I have to agree with you Bart...

Seems like we are seeing both wideangle perspective at work with some lens barrel distortion, probably from a wide or moderately wide zoom lens and setting on a DSLR... Since none of those options could generate the 300mm/f2.8-ish DoF as shown, it almost certainly is photoshopped in. And since it is also monotone, we can be reasonably assured it has been through PS for that, so adding the blur vignette would be trivial. If it had less defined detail on the skin, I might even consider a cell-phone or video frame grab

Could you achieve this sort of effect with the 24mm TS-E (tilt-shift) lens?

Have seen some pretty wacky DoF effects with these lenses, have never used one though so don't know if this sort of thing would be possible.

ok, here for comparison is a shot at f1.2 on 85mm (of yours truly!) with a full sized 35mm chip. After looking at this shot of myself, I'm learning more towards a normal or medium length lens, no slightly wide lens.

If this was shot on 35mm, I would guess that it's either a 50 or an 85 at f1.2, possibly 1.4 or 1.8. It looks like the camera was positioned a bit higher up on the shot of Obama, and he is looking up towards the camera slightly, where as the camera in my shot is ehe level, and I'm looking down slightly, which makes my chin go out of focus. That also makes his shoulder line intersect the head a little farther up than my shoulder line does. This possibly could be aiding the feel of a slightly wider lens? My face (and nose) is taller and thinner looking than his too, which may also make the focal length comparison a bit tricky. Obama's nose and mouth is wider than mine, and his hears stick out more than mine, which may be giving the feel of a wide lens, even though ears sticking out wouldn't really happen with a wide lens (I think) it may give the image that feel.

Now I'm curious as to what the actual shot was taken with! Anyone know who the photographer was? Does he/she usually shoot 35mm? or large format?

Daniel Buck said:

If this was shot on 35mm, I would guess that it's either a 50 or an 85 at f1.2, possibly 1.4 or 1.8. It looks like the camera was positioned a bit higher up on the shot of Obama, and he is looking up towards the camera slightly, where as the camera in my shot is ehe level, and I'm looking down slightly, which makes my chin go out of focus. That also makes his shoulder line intersect the head a little farther up than my shoulder line does.

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Hi Daniel,

I like your eye level camera position better, you look more presidential

I'm leaning towards a 50mm on an uncropped 24x36mm sensor array, or similar on other sizes. His ears look relatively small, compared to the longer distance shots we see on TV, so it must have been a close-up. The DOF in Obama's portrait still looks a bit photoshopped to me, it goes OOF too abruptly. The DOF in your portrait transitions much more gradual.

Now I'm curious as to what the actual shot was taken with! Anyone know who the photographer was? Does he/she usually shoot 35mm? or large format?

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As a photographer it intrigues me as well. Was the choice deliberate, was it a snap, was it a session? Anyone in the Chicago area happen to have a copy of the magazine?

Bart

50

I think it could easily be a 50 1.2 on a FF body. or a 35 1.4 more likely. I've done a number of shots with my 50 where the low dof has put center fact in focus. Most of the journalists that I have met that do street work use the 50 1.4

If it was a 50 on FF35, then it appears Obama has a larger than normal nose, lips and chin, and they protrude more than normal? Or maybe the lens used has excessive barrel distortion? By contrast, Daniel's portrait appears pleasantly flatter (normal) albeit with similar DoF/oof rendering. Since the DoF is similar, I would suspect that if it were a 50, it would have to faster than the 1.2 on the 85...

One option might be an older Canon 50 f1.0 lens, but I'm sticking with a wid-ish zoom at around 35mm (zooms usually exhibit more distortion) and photoshopped DoF.

The camera seams to be relatively close to the sitter. We supposed that the effect of shallow depth of field is analog --as opposed as the effect of a PS filter--, something that would be the logical conclusion since this is an editorial image. Remember the cover or Shara Palin on Newsweek that was commented because it showed her face with "extreme detail", and the magazine said: "We don't retouch, period".

So, this is a "NORMAL' lens wide opened or it is a larger format than "FF", so I would go for 8x10. ...

Another vote for a fake DOF plus a not to extrem wide; how about a 35 mm/FF-relation?

OK, lets forget about format and/or lens specs, what about "real" against digital DOF. That should make a good game.

I, as stated, would bet for analog DOF.

a) politically incorrect to retouch a news cover photo
b) it would be a difficult thing to do. Apply a out of focus effect on a background is one thing, on the President of the USA's face...
c) how do you sell the idea to the magazine's editor? you show him a portfolio of fake DOF portraits?
d) using a wider-than-normal lens in 35mm and faking DOF makes no sense, why not use a 85 Nikkor 1.8 or faster short tele? On the other side, if you are using an 8x10, you may want to have a fast normal for several reasons...
f) my gut feelings tells me: view camera

The portrait above was done with a 15 inch f4 petzval wide open on 8X10.

I sent an e-mail to Brooks about the one in question, but he hasn't responded.

leonardobarreto.com said:

OK, lets forget about format and/or lens specs, what about "real" against digital DOF. That should make a good game.

I, as stated, would bet for analog DOF.

a) politically incorrect to retouch a news cover photo
b) it would be a difficult thing to do. Apply a out of focus effect on a background is one thing, on the President of the USA's face...
c) how do you sell the idea to the magazine's editor? you show him a portfolio of fake DOF portraits?
d) using a wider-than-normal lens in 35mm and faking DOF makes no sense, why not use a 85 Nikkor 1.8 or faster short tele? On the other side, if you are using an 8x10, you may want to have a fast normal for several reasons...
f) my gut feelings tells me: view camera

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I would agree, I don't think it would be proper to manipulate images in this way for magazines, especially presidential candidates. However, the fake DOF can be done. Here's one I whipped up (I did not take this photo), using a compositing program, I drew a soft bezier around his face and used that for the z-depth mask for the z-blur. If one puts a bit more time into getting a real good z-depth mask (areas that fall off quicker than others, and more detail in the map), I imagine the results would probably fool even seasoned photographers looking at the print. But even with a quick 5 minute hack, I think 90% of the general public would not give this image a 2nd look and pass it off as not being altered.

Looking at Jims image and yours, and not having any objective argument my intuitions is more convinced towards the "organic" DOF than an artificial.

What is the name of the photographer that took the photo for the original cover, can we go to his web site and find out if he actually uses a large format or has done this before?

I think it's probably real short DOF. The recess between his lower lip and chin is outside the DOF zone, but the chin is in.

Martin Schoeller often shoots in this style, usually on 4x5", but he usually uses a plain background and shoots even tighter, so it's probably someone else. On the other hand, shooting for a cover, he would have to leave some space for text, so maybe.

Looks like it was probably done with a normal focal length, if the format is 4x5" or larger.

It is simple really, call The President Elect Mr. Obama, he may remember what they used... but on the other side, he may have had so many portraits taken ... we will probably never know

The proportions of the human face change with age but for a man in his late 40's the length of an ear is very close to the length of the nose. The distance, front to back, from the ear to the nose is a remarkably consistent 150mm for normal faces in this age group.

Near things look bigger than far things and at normal portrait distances noses look bigger than ears. If a nose looks twice as big as an ear you can be pretty sure it was twice as close to the camera. Measuring the Obama picture suggests that the nose is depicted about 10% longer than the ear so it was 10% closer. Doing the arithmetic suggests that the Obama picture was taken from about 1.5 metres away. This is a typical portrait distance when the photographer is close enough to be attentive and respectful but not so close as to invade personal space.

The lens focal length needed to get a face picture that fills 70% of the format frame at 1.5 metres varies with format but it is about 3 times whatever is the "normal" lens for that format.

Hi, Maris,

Maris Rusis said:

The proportions of the human face change with age but for a man in his late 40's the length of an ear is very close to the length of the nose. The distance, front to back, from the ear to the nose is a remarkably consistent 150mm for normal faces in this age group.

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Interesting information and nice insight. Thanks.

Best regards,

Doug