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07-12-2010, 09:52 AM   #1
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Focal Length/Field of View Comparison?

I've been looking for photos of the same scene taken with different focal lengths and haven't had much luck.

It appears that the smaller the focal length the bigger the different in the field of view?

Therefore the difference between 15mm and 21mm would be huge but the difference between 35mm and 40mm (or 41mm if it existed) would be less noticeable?

I've seen many threads talking about what what lenses they should get next with great responses, positives and negatives, some even include pictures to show how great or how bad (not as often) they are.

But I haven't seen anything strictly from a focal length perspective. Should I go wider and crop? If so how much would I have to crop? Should I just use my feet and move... sure, but how much do I have to move?

I'm specifically interested in the da limiteds, but any focal length comparisons would be helpful.

I'm thinking about getting 3 new lenses, the 15mm or 21mm along with the 40mm and 70mm (starting with the 40mm currently listed in the wanted section)

If anyone has taken these photos I'd love to see them or if they could point me in the right direction that would be great. Thanks -Dave-

07-12-2010, 10:10 AM   #2
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Focal length comparison tool, Tamron USA
07-12-2010, 10:17 AM   #3
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Wikipedia article on focal length has pictures of the same scene taken with different focal lengths.

QuoteOriginally posted by dmoon911 Quote
I've been looking for photos of the same scene taken with different focal lengths and haven't had much luck.
07-12-2010, 10:47 AM   #4
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I guess that's why there are no posts on the subject here... perfectly explained and demonstrated. I especially like the Tamron one. Thanks for your quick responses.

07-12-2010, 05:35 PM - 1 Like   #5
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Hold your fist in front of your face with your elbow bent at a right angle; use your knuckles to select the lens you want for the scene behind your hand:

4knuckles:50mm, 2:100, 1:200.

The trick is figuring out where to hold your fist so the above rule holds. Try it a few times.

Take a photo of a scene with a 50mm lens (or look through the camera's viewfinder with a 50mm lens in place.)
Put the camera down & hold your fist in front of your face such that the 4 knuckles just fill that scene height.
Remember where to hold your fist next time you want to select a lens.

Dave in Iowa

Last edited by newarts; 07-12-2010 at 08:51 PM.
07-13-2010, 03:56 AM - 1 Like   #6
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Here's one I prepared earlier. It's not perfect, but hope it helps:

02-27-2011, 05:09 PM   #7
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Here's my take:

Total "high tech" means of figuring it out


(done as a *.png to overlay on your photos, feel free to use)


Here's a shot I did at 10mm & overlay'd the graphic. If you're shooting at less UWA, you can set to one of the more common lengths on the grid.


Lenses used:
sigma 10-20
da40
sigma 28-80
a70-210

Last edited by John Araki; 02-27-2011 at 05:37 PM.
02-27-2011, 05:32 PM   #8
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A bit late to the party, but I actually finally did this comparison earlier today for myself.

15.


21.


40.


70.


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