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03-31-2012, 03:58 AM   #1
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FA 31mm as a potrait lens vs FA 77mm (not taking into account FOV)

hi guys

i just ordered the FA 31mm and im hoping to use it as general purpose lens.my question is since its also good For portraits with great out of focus renderings, will i gain any thing extra in terms of out of focus rendering and bokeh in the FA 77mm since i can crop the 31mm to get the FOV of the 77

thankz

03-31-2012, 04:24 AM   #2
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Its a good enviromental portrait lens (full body + surroundings) but not as a head and shoulders portrait lens like the FA77.
Yes you could crop but you would need to crop alot but it wouldnt make it flattering like a FA77 would or give a shallow DOF.

Last edited by TOUGEFC; 03-31-2012 at 04:49 AM.
03-31-2012, 04:32 AM   #3
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+ one for Simon's comments. I have both and find that to crop down to a similar FOV as the 77 is just pushing things a bit. To get a nice portrait with the 31 you need to get in very close and then things get a tad distorted. The 31 stays on my camera as the standard lens, but I find that for those head and shoulders the 77 shines (and you don't have to get in in their face or crop the hell out of your image).
03-31-2012, 04:32 AM   #4
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Hi,
I have both lenses and I find FA 31 not that great for head and shoulders portraits. To get a shallow DOF with 31mm you have approach very close to subject and since it's a wide angle lens, you get somewhat funny effects like big nose or eyes (I'm talking about 0.5-0.7m distance). It is much more suitable for body-length portraits or if you want to take a picture of several people but expect that you'll get somewhat detailed background in that case. Also, I find my copy of 31mm softer wide open than 77mm and only stopped down to 2.8-5.6 it really shines. However, you can get a blurry background with 31mm if you have a few meters of empty space behind your subject even if you stop it down to 4.0-5.6
So I use mostly 77mm for single-person or head-and-shoulders portraits. Also it is worth to mention that in tight spaces like living rooms, 43mm suits perfectly for waist and up portraits.

Note, that cropping 31mm won't give you the same DOF as 77 provided both are used at the same distance.

(you've got already two similar comments while I typing )

03-31-2012, 08:05 AM   #5
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It's not exactly the same comparison, but to pronounce what happens when you use a 30ish mm fl to do head and shoulders shots, have a photo taken by the Sigma 30/1.4 @ 1.8 taken from about 4 feet away.



She does naturally have a somewhat pronounced nose, but it seems quite large here. A longer lens would tend to compress that particular feature. Another thing with using a bit wider focal length to do head and shoulder portraits is you might have to get more creative with angle to portray the shot that you want. "A little to the left, turn your head a bit... there!"

Now, the FA77 is on my short list of lenses yet to get. I'd say if you're not going to use a lens for its intended purpose, get ready to work around it. It can be very fun for creativity in that regard.
03-31-2012, 09:02 AM   #6
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+1 on above. I use my comparable 28/2 for many things, but not for headshots, not of people with whom I want to stay on good terms. The conventional wisdom here is roughly: 20mm for context, 30mm for full-body, 40mm for 3/4 body, 50mm for 1/2 body, 70mm for head+shoulders, 80mm for loose headshots, 100mm for tight headshots. An 18-135 or 18-250 will make this breakdown quite clear to you: test various focal lengths and distances, see what works for you and your subjects.

As for those blurry backgrounds you want: DOF is photographically controlled by aperture, focal length, and camera-subject distance. Here are the rules again:

* For thinner DOF, use a wider aperture and/or longer focal length and/or closer distance
* For thicker DOF, use a tighter aperture and/or shorter focal length and/or further distance

But subject isolation is also affected by lighting and subject-background distance. A well-lit subject stands out from a darker or bland or moving background (BG). A further BG is blurrier than a closer BG. A fast short lens won't produce the effect you want if camera-subject distance is too far, the subject-BG distance is too close, the subject isn't lit, the BG is too bright or busy. ALL THESE OTHER FACTORS MATTER MORE THAN THE LENS! My Kodak guidebook to portraiture barely mentions lenses, instead emphasizing lighting, poses, clothes, makeup, but especially lighting.

My favorite head+shoulders and headshot setup, whether with APS-C or 135/FF or 120/MF cameras, is about 80/3.5 shot from 1.5-2m with an indistinct BG about 3x further away. IMHO this gives the best modeling|rounding of human features, and best minimalization of BG. If you lack such space, use careful lighting. Try it and see, eh?
03-31-2012, 09:03 AM   #7
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+1 on above. I use my comparable 28/2 for many things, but not for headshots, not of people with whom I want to stay on good terms. The conventional wisdom here is roughly:

* 20mm for context
* 30mm for full-body
* 40mm for 3/4 body
* 50mm for 1/2 body
* 70mm for head+shoulders
* 80mm for loose headshots
* 100mm for tight headshots

An 18-135 or 18-250 will make this breakdown quite clear to you: test various focal lengths and distances, see what works for you and your subjects.
_________________________________

As for those blurry backgrounds you want: DOF is photographically controlled by aperture, focal length, and camera-subject distance. Here are the rules again:

* For thinner DOF, use a wider aperture and/or longer focal length and/or closer distance
* For thicker DOF, use a tighter aperture and/or shorter focal length and/or further distance

But subject isolation is also affected by lighting and subject-background distance. A well-lit subject stands out from a darker or bland or moving background (BG). A further BG is blurrier than a closer BG. A fast short lens won't produce the effect you want if camera-subject distance is too far, the subject-BG distance is too close, the subject isn't lit, the BG is too bright or busy. ALL THESE OTHER FACTORS MATTER MORE THAN THE LENS! My Kodak guidebook to portraiture barely mentions lenses, instead emphasizing lighting, poses, clothes, makeup, but especially lighting.

My favorite head+shoulders and headshot setup, whether with APS-C or 135/FF or 120/MF cameras, is about 80/3.5 shot from 1.5-2m with an indistinct BG about 2-3x further away. IMHO this gives the best modeling|rounding of human features, and best minimalization of BG. I now use a 75/3.5 enlarger lens (under US$10) on extension for sharp headshots.
_______________________________

Note on headshot lenses: The AOV differences of headshot focal lengths are trivial. The angles on my K20D are like this:

70mm 23 degrees
75mm 21 "
80mm 20 "
85mm 19 "
90mm 18 "

In other words, any decent lens in that range will give a similar view. The trick is in knowing how to use it, eh?

Last edited by RioRico; 03-31-2012 at 06:11 PM.
03-31-2012, 05:29 PM   #8
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thanks for the great info. so i guess either a 70mm or 77mm has to be in my bag as well

03-31-2012, 05:32 PM   #9
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I would consider these complimentary lenses rather than alternatives to each other. Its kind of like a putter and a 9-iron.
03-31-2012, 06:18 PM   #10
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QuoteOriginally posted by nirVaan Quote
thanks for the great info. so i guess either a 70mm or 77mm has to be in my bag as well
Those would work. So would an 85mm, or a 90mm macro. As I mentioned above, their AOVs are very close.

If you really want a 70-80mm and already have a Fast Fifty, you can get a good+inexpensive 1.4-1.5-1.7x front-mount (screw-on) teleconvertor like those from Sony, Olympus, Canon, etc. I mount my Sony VCL-1546A (1.5x) onto my FA50/1.4 and get a 75/1.4 optic. A member here is selling something similar for $45.
04-01-2012, 03:46 AM   #11
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FA31 is a retrofocus wide angle design for full frame cameras. You can still take portraits with it, but you pay the price of a full frame wide angle, plus you get the inherent distotion of such lens. I would never buy a lens assuming that I can crop to a lens with more than double the focal length. The DA*55 is perfect for portrait on an APS-C sensor.
04-03-2012, 03:49 AM   #12
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keep a little distance between the subject and you. my untrained eyes often don't see too much distortion with portraits shot with FA31.


04-03-2012, 04:00 AM   #13
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nice pic btw but this is taken with a fa43 right.any ways FA 31 seems to be a great lens
04-03-2012, 04:19 AM   #14
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QuoteOriginally posted by nirVaan Quote
nice pic btw but this is taken with a fa43 right.any ways FA 31 seems to be a great lens
taken with a FA31. FA43LTD is my flickr ID.
04-03-2012, 05:02 AM   #15
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great set of pics. but having looked at soo many pics from many lenses it seems FA 35 f2 is the best when price performance is concerned (many ppl said it bokeh is bad put i only noticed it in a very few occasion and its as sharp as any limited )
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