PDA

View Full Version : Perspective in portraits of people


Hulk
01-09-2010, 03:16 AM
I love taking pictures of people. Seems like a longer lens works better, although you need the space to be able to move away from your subject.

I saw this web page many months ago and have been looking for it ever since. It's a comparison of different length lenses on portrait shots, which shows the distortion that wide angle lenses give and why they're not a great choice for portrait shots. This should be obvious, but I didn't understand it until I saw it.

Check it out (http://stepheneastwood.com/tutorials/lensdistortion/strippage.htm).
Here's a thumbnail view (http://stepheneastwood.com/tutorials/lensdistortion/index.htm).

Opinions? Advice? I'll admit, I'm still barely beyond the newbie stage.

Hulk
01-09-2010, 03:53 AM
I'm posting this photo and explanation from something I discovered on the Pentax forum.

First, here's the photo.

Hulk
01-09-2010, 03:55 AM
Here's the explanation, which makes me understand the issue even better than the pictures did.
No. I think you're misunderstanding just what perspective distortion actually is.

In your garage picture, perspective is why the gray plastic storage tub on the floor along the left wall toward the *front* of the garage appears much larger than the (presumably) matching tub on the floor along the left wall toward the *back* of the garage. The one in the front looks bigger in this picture because it is so close compared to at the back. That is because we are using a wide angle lens that requires us to stand close to the garage in order to fill the frame.

Zoom to 250mm, and you'll have to stand *much* further away from the garage in order get the whole garage in the frame. When you get to the right distance, you'll find you are so far away that the distance between the two gray tubs pales in comparison to your distance from either of them. So the same picture would show *much* less difference in apparent size.

It works similarly for other objects in the garage. When you are close to it, as you need to be at 18mm, objects at the fron of the garage appear much larger than obejcts at the back of garage. Step back and shoot from 250mm, and things even out more.

This phenomenon is basic Perspective 101 and has been known to artists for centuries - it has nothing to do with lens distortion. It pretty much *completely* explains what the portrait demonstration was showing. At the longer focal lengths, the photographer was far from the subject, so all facial features were approximately the same distance away. As the photographer switched to shorter focal length, he had to move in closer and closer, and as he did so, the difference between the *front* and *back* of the head got more and more significant, just as it did with your garage. So features on the front of the face appear *much* larger and *much* closer than features toward the back of the face. This leads us to perceive the face as very distorted, but it is not the lens that is doing this distorting - it is an inevitable fact of being so close to the face.

We don't notice this in person because our binocular vision helps us make sense of things in three dimensions, but the effect can be very disorienting when reduced to two dimensions, as in a photograph or painting. And this effect is especially disorienting when it happens to a face, because of the special way our brain processes faces.

So what I'm saying is, even in a lens with 0% distortion, those wide angle views would have looked pretyt much exactly as distorted as they do here, because that's what perspective does to faces when you get that close.
Original thread here (http://www.pentaxforums.com/forums/pentax-slr-lens-discussion/36957-focal-length-comparison-tools.html)

Inukshuk
01-09-2010, 05:30 PM
I like using longer lenses as much as possible. You get lots of control over depth of field.

RockRunner
01-10-2010, 09:38 AM
I have used my 80-200 a lot for portraits and you'll see a lot of pro's doing the same. I do have a "portait" lens, it is a 100mm that has a soft edge to it. I was able to get some beautiful shots of a bride once that sold like crazy. If you shoot Canon you are more than welcome to try it.

Cheeseman
01-11-2010, 01:03 PM
In the portrait world a popular lense was the 85f2 lense. I have one if you want to try it. Closer, wide angle, lenses tend to round the face. Long lenses tend to flatten the face. You can see this in your example. So practice. Zoom lenses are known for having the most effective optics not, not at the extremes of the zoom. But rather just inside either end of the zoom. One thing to check on wider lenses is what they call perspective control. Term? Architectural photography counts on this part of optical physics. If you take the particular wide angle lense and look at this garage door and just move up and down you will see the sides angle in and out depending on your angle ot approach to the doors. IF you shoot it level the doors will show themselves as parrellel not skewed top to bottom or viceversa. So sometimes you have to change your elevation or stance to make this work for you. So check on this.
________
Codeine rehab advice (http://www.rehab-forum.com/codeine-rehab/)

Hulk
01-11-2010, 01:20 PM
In the portrait world a popular lense was the 85f2 lense. I have one if you want to try it.

That sounds great. One thing I have been concerned about is the 1.5x factor of the DX cameras, like mine. It would be cool to try out your lens.

Closer, wide angle, lenses tend to round the face. Long lenses tend to flatten the face.

So the longer the lens, the more accurate the representation of the face? Or is there a sweet spot somewhere between rounder and flatter that I should aim for?

Thanks for all your comments, guys!

MountainMan
01-11-2010, 01:56 PM
pretty interesting thanks for sharing, had not considered it, not a photophile, but i like learning stuff like this, it's cool

Cheeseman
01-11-2010, 02:16 PM
You know I always forget the 1.5x factor. Luckily it doesn't change the f-stop much. So I would then check 50mm and the 85 and see what you think.
________
Coach Purses (http://icoachhandbags.com/)

CardinalFJ60
01-11-2010, 04:13 PM
Cheeseman is spot on. I'll use either my 85mm/1.8 or my 50mm/1.4 for portrait stuff. on my DX format the 50mm is more like a 75mm so I can be further from the subject (more comfortable for them) and get a nice perspective (no horse faces nor really flat). the nice thing with a fast lens, is that you can shoot the protrait at like f2.2/2.8/3.5 and get a nice Bokeh in the background.

if you want to 'bring' the background forward, use a long lens - it will also magnify the background, making it appear closer to the subject. (think a nice mountain in the background -with a really wide angle lens, you'll need to be close to your subject, which is fine. that also means the background will appear further away. if you grab your 70-300 and rack it to like 200, you will stand further from your subject (although it will still fill the frame similarly), and the mountain in the background will look a little closer.)

Cheeseman
01-11-2010, 06:38 PM
Ah good stuff Cardinal. I wasn't going to get into that lesson yet. One step at a time.
________
Iolite Vaporizer (http://vaporizer.org)

CardinalFJ60
01-12-2010, 07:10 AM
Hehe...after I typed that, I was thinking, "did I say too much??". :D I probably shouldn't divulge alllll the cool tricks, not yet anyway.

This new forum is gonna be fun! Taking lots of pictures is definitely my new obsession.

Hulk
01-12-2010, 05:24 PM
I appreciated what you said very much. My brain is full of "how do I do this...?"

It made me think of the photo we took at Mt. Rushmore this last summer. The background is sharp; we in the foreground are soft. It's not as obvious with the photo in a web-friendly size, but it's really bad at full size.

There was something I could have adjusted with the aperture to fix this right?

http://www.risingsun4x4club.org/forum2/attachment.php?attachmentid=16238&stc=1&d=1261465213

Cheeseman
01-12-2010, 06:14 PM
Yup the great science of aperature. Hard to fathom for some. difficult for the rest. The general rule of thumb is this 1/3 front -2/3 behind the subject. Now the tricky part is this gets "deeper" with the bigger the number on the aperture ring. On older lenses there are numbers on either side of the focus line on top of the lense. these numbers show corresponding to the "depth of field" on the lense. On newer lenses these numbers on top of the lense don't exist anymore so you kind of have to just learn what they are. Also on most camers there is a depth of field preview button usually located on the lower front of the body the you would activate with your right hand finger.

so bigger the f stop the bigger the depth of field. And with thirds rule you can cheat this distance by putting your subject in a different place than what the camera wants to focus on. Best practice is on a long fence.

this is probably the hardest concept in Photography. Read more from the Art Wolfe book that you have from me. It should help.
________
Milf Tubes (http://www.****tube.com/categories/28/milf/videos/1)

Cheeseman
01-12-2010, 11:20 PM
It all depends on what you're after. And pleasing to your eye. There is no right or wrong until you get to the big boys which I have spent some time with. Then you will learn what is right and wrong. But knowing a few rules will make your shots more pleasing to you and your viewers. Someday I'll learn how to put shots into these posts so I can show you all some things I have learned. But I don't know how to do that yet.
________
Babe sex (http://www.****tube.com/categories/6/babe/videos/1)

Hulk
01-13-2010, 03:09 AM
Dave, thanks for posting all the samples. So do I have this right? The smaller the aperture, the greater the depth of field, which would have improved my Mt. Rushmore photo. And the smaller the aperture, the larger the f-stop: f2.8 is large (wide open to let in lots of light) while f32 is very small.

Now I need to figure out how to manually control my aperture while allowing the camera and lens to work the rest of its magic.

Hulk
01-13-2010, 03:32 AM
I'll use either my 85mm/1.8 or my 50mm/1.4 for portrait stuff. on my DX format the 50mm is more like a 75mm so I can be further from the subject (more comfortable for them) and get a nice perspective (no horse faces nor really flat). the nice thing with a fast lens, is that you can shoot the protrait at like f2.2/2.8/3.5 and get a nice Bokeh in the background.

Which 50mm/1.4 did you buy? I see two nice AF 50mm lenses on B&H:

AF-S Nikkor 50mm f/1.4G
AF Nikkor 50mm f/1.4D

I have a couple of fixed lenses that are my faves:

AF Nikkor 50mm/1.8
AF Nikkor 35mm/2 (current fave)

These are older lenses, not the D series.

ElliottB
01-13-2010, 09:28 AM
You guys really seem to know your stuff. I need to bring one or more of you to Vail to catch some action shots. My friend's camera phone just ain't cuttin' it. :D

Hulk
01-13-2010, 11:01 AM
Other than the speed I think you have two very fine lenses and certainly much better photographers have made much, much better images with lesser glass. Most people feel the 50/1.4 and 35/1.4 give up a little optically over the 50/1.8 and 35/2.0 for their speed. So unless you find you need the extra 1/2 stop a lot, it's often money better spent elsewhere.

Dave, thanks for all of this. I was curious as to how much of a difference a 1.4 would make over a 1.8. Sounds like at my skill level, not much.

Your Germany pictures are outstanding. Do you scan everything yourself or get scans from the developing place you use?

CardinalFJ60
01-13-2010, 12:27 PM
for the money, the 35mm 1.8 can't be beat. I have the 50 1.4 and used to have the 1.8...I rarely shoot the 1.4 wide open cuz it get a tad soft on the edges. but at 1.8 and up it's SHARP! the 1.8 was sharp from f2/f2.2 up. a negligable difference at that.

save your dough go 1.8.