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12-03-2009, 09:54 AM   #1
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Lens for group portrait

What lens you usually use for taking group portrait (maybe 5 or more persons)?
I usually use DA 12-24mm (Samsung's clone) but most of the time I get this distortion, that makes the people looks shorter and also chubbier (usually the guys who get chubbier are those who stand on the side)
I usually take group portrait of my friends and they complained more than once already..

When distortion is discussed in lens review it's always about distortion to vertical or horizontal lines. I wonder if this has relation with the above characteristic?


Last edited by sajah; 12-03-2009 at 10:26 AM.
12-03-2009, 10:20 AM   #2
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Your m 28/3.5 will do just fine I'am sure.
Allmost distortion-free and very sharp.
I own one myself.
Never go wide-angle or to close
to people when you want to play save.
12-03-2009, 10:39 AM   #3
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Thanks, freewheeler. Yeah I need to put the 28mm to the bag more often, it's a very pretty lens, small too. I like it when it's mounted on my DS.

But, still a bit curious, this 'effect' can not be avoided with wide angle lens eh? Because when using 28mm sometimes I can't get further enough to get everyone's inside the frame (usually when indoor). Would, say, a decent distortion free 20mm be better for this purpose? I meant, I'm asking whether this is the limitation of my 12-24 lens or it's just something I have to deal with when using wide lens?

Last edited by sajah; 12-03-2009 at 10:52 AM.
12-03-2009, 11:09 AM   #4
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QuoteOriginally posted by sajah Quote
Thanks, freewheeler. Yeah I need to put the 28mm to the bag more often, it's a very pretty lens, small too. I like it when it's mounted on my DS.

But, still a bit curious, this 'effect' can not be avoided with wide angle lens eh? Because when using 28mm sometimes I can't get further enough to get everyone's inside the frame (usually when indoor). Would, say, a decent distortion free 20mm be better for this purpose?
I believe that would be impossible due to the nature of the UW lenses. lens element curvature is a necessity inorder to achieve a wide perspective. making a distortion free 20mm would mean a longer and heavier glass and may a much bigger front element inorder to suffice a distortion-free effect at wide angle. maybe it's front element would be atleast 82mm diameter or more in size inorder to have a 12mm distortion-free view. for me, I would rather have a lens with a slight distortion which is easily correctable by softwares rather than spend on a probably expensive distortion-free glass which would cause me problems during use and transport. portability is key for me atleast. that is why composition is critical when using a UW lens.


Last edited by Pentaxor; 12-03-2009 at 03:08 PM.
12-03-2009, 12:44 PM   #5
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All true.
Nevertheless there are cases when large group shots in relatively small working spaces warrant the use of an ultrawide. I have taken shots for a group of 250 student and needed to fall back as far as I could before something got in the way of the shot and even then I needed 16mm to get everyone in. And for some whole family group shots at weddings I have resorted to going to 14mm, which isn't ideal but what I had to work with.

So for your purposes, if 28mm isn't wide enough, using the 12-24 is OK, just as long as it is used at the longest focal length you can possibly go to ensure everyone's comfortably in the shot.
12-03-2009, 12:57 PM   #6
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I see. Thanks for the detail explanation, Pentaxor. I sure dont want to carry lens that big haha

Ash, yeah I will try to keep that in mind, thanks!
12-03-2009, 12:57 PM   #7
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It's not "distortion" in the sense of a lens defect tht is the problem here . That wouldn't be making them look fat - it would just be making the stripes on their shirts look a little wavy. The effect you're describing is a simple fact of perspective - you are taking a scene that is far wider than a "normal" field of view, and then viewing it in a print or on a monitor from a "normal" viewing distance. This causes an illusion known as "perspective distortion". Stick your face up closer to the print so it ends up being as wide in your vision as the original scene was, and that illusion goes away.

So basically, you minimize the effect by not shooting so wide. Go with the longest focal length you can that still allows you to fit everyone in. If you have the luxury of plenty of space to work with, step back far enough so that the group comes closer to fitting a "normal" field of view. Arrange people in rows if possible, or at least in an arc. Do whatever you can so that you don't need such a wide angle view.

I suppose there might be some clever tricks for minimizing the effects of perspective distortion if you do have to shoot ultrawide. You could put skinny people on the edges. You could experiment with turning people full or partial profile to find the most pleasing angle for the distortion. I find some of the group shots I've taken with my DA15 - my first ever ultra-wide - show the effect more strongly than others. Mostly, I try to keep people from the extreme edges. Which is to say, I crop the shot to give the same FOV as a 21 or so...
12-03-2009, 01:55 PM   #8
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That's an interesting trick

Cropping, didn't think about that. It can work too if I don't have 28mm with me, provided that I have enough space to move way back, of course.

12-03-2009, 03:17 PM   #9
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to add more to Marc's recommendation, step back further where you could cropped the unused distorted portions of the image. as Marc pointed out, cropping out an image shot by a 15mm could result to a 21mm shot. but shooting father away, this would compensate the longer focal length effect caused by cropping, thus maintaing the image entirety.
12-03-2009, 03:40 PM   #10
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I use the DA10-17mm for large group shots and shoot at 17mm. Place the people along the Centre line (with plan to crop later) and make a slight adjustment for the remaining FE effect (if needed)...and there ya go.

Works for me.

This all being said if everyone doesn't fit in my 30mm Sigma lens.

c[_]
12-03-2009, 06:31 PM   #11
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I got curious since I just shot a group picture with my DA15 a couple of nights ago. I just sort of picked a place to stand where everyone would fit comfortably in the frame, then cropped when I got home. I ran the numbers, and if I did it right, it appears I cropped to the equivalent of 17mm. I calculated this by dividing the width of the original image by the width of the cropped image to get a "crop factor" (1.16), then multiplied this by 15. Does this make sense as methodology? I tried to emulate how I'd imagine cropping an FF picture to to simulate APS-C.

Here, BTW, is the picture. The only area where I'm instantly aware of any issues is in the foot of the guy on the far right, although the guitar in the lower left corner is also showing signs of perspective distortion:



Assuming I calculated correctly, this suggests 21mm would not have been wide enough for this shot, although of course I could have stepped further back, which probably would have been a better choice anyhow.
12-03-2009, 06:45 PM   #12
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QuoteOriginally posted by Marc Sabatella Quote
I got curious since I just shot a group picture with my DA15 a couple of nights ago. I just sort of picked a place to stand where everyone would fit comfortably in the frame, then cropped when I got home. I ran the numbers, and if I did it right, it appears I cropped to the equivalent of 17mm. I calculated this by dividing the width of the original image by the width of the cropped image to get a "crop factor" (1.16), then multiplied this by 15. Does this make sense as methodology? I tried to emulate how I'd imagine cropping an FF picture to to simulate APS-C.

Here, BTW, is the picture. The only area where I'm instantly aware of any issues is in the foot of the guy on the far right, although the guitar in the lower left corner is also showing signs of perspective distortion:



Assuming I calculated correctly, this suggests 21mm would not have been wide enough for this shot, although of course I could have stepped further back, which probably would have been a better choice anyhow.
with a 14.6 MP sensor, that won't be a problem. moving back far-away to emulate a longer focal length could do the trick in cropping out the unwanted perspective distortion. however, perspective distortion would still be unavoidable with images shot at an awkward angle. there are just situations that you need to shoot a particular shot at that angle.
12-04-2009, 02:43 AM   #13
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QuoteOriginally posted by Pentaxor Quote
with a 14.6 MP sensor, that won't be a problem. moving back far-away to emulate a longer focal length could do the trick in cropping out the unwanted perspective distortion. however, perspective distortion would still be unavoidable with images shot at an awkward angle. there are just situations that you need to shoot a particular shot at that angle.
I've been using an UWA this past few weeks and I have to agree..
12-04-2009, 03:16 AM   #14
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If you shoot at let's say 15mm and then crop to get something like 17mm, you end up with the same result as if you had taken the picture at 17mm to start with. There is no free lunch anywhere.
12-04-2009, 12:30 PM   #15
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QuoteOriginally posted by flyer Quote
If you shoot at let's say 15mm and then crop to get something like 17mm, you end up with the same result as if you had taken the picture at 17mm to start with. There is no free lunch anywhere.
Right; sorry if I wasn't clear about that. It's all about how far away you stand - nothing else. If you stand at a location that gives you the framing you want at 17mm, then you get the same perspective regardless of which (rectilinear) lens you use.

My comments were about how to make use of this in fact in practice: if your lens is wider, don't use it so as to fill the frame, Use it as if it were a little longer. Not to get *better* results that you would have if you had a 17mm lens, but to get the *same* results. I'm just curious if I did the calculation correctly. It always strikes me as counterintuitive to expect focal lengths to scale linearly like that. Which is to say, I'm amazed the idea of a crop factor actually works for calculating FOV equivalence.
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