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03-16-2011, 02:56 PM   #1
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Question regarding FA 31mm f/1.8

Hello, I currently own DAL 35mm f/2.4 i'm very satisffied with it, however, two things bother me.
better bokeh
and wider FL
so

the answer is FA 31mm

My question is will FA 31mm have the same or even better low light AF?

or will it be slower?

because this factor might be the main factor in whether I will be able to take the pic or not.

and if not, then it doesn't matter if it's bokeh is better, it's not existing..

so, those who could compare, low light AF of both lenses, which one is better.

I would be very gratefull.

03-16-2011, 04:28 PM   #2
hcc
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I do not have the 35mm but I have the FA31 mm f1.8. I can compare it with my Voigtlander 58mm f1.4 and my Tamron 90mm f2.8.

The FA31mm f1.8 is doing very well in low-light. It is certainly fast, almost as fast my Voigtlander (f1.4). My FA31mm is definitely much faster than my tammy f2.8.

I would expect that the FA31mm be quite faster than the 35mm f2.4.

Hope that the comment will help.
03-16-2011, 05:55 PM   #3
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The 31 is better, but not by an astonishing margin.

Woops, I read that as DA35, not DAL.
Forget whatever you read from me.

Last edited by Wheatfield; 03-16-2011 at 09:15 PM.
03-16-2011, 09:07 PM   #4
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AF will likely be more hit and miss in low light compared with the DAL because of the wider aperture, which results in lower contrast that can be taxing on the AF system in low light.

Whether it will be substantially different though, I cannot say. It would likely be just fine, however moderate-aperture lenses like the DAL tend to be the fastest in the AF department.

03-16-2011, 09:16 PM   #5
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I think you will struggle to find someone who owns the DAL35 and the FA31. If someone owns the FA31 why would they buy the DAL35, and if someone had the budget to only buy a DAL35 a couple of months ago, how many would have found $1k so soon for a FA31.

My 2cents, as I own the FA31, is that I haven't noticed it to have slow AF at all. My gut feelking is that it is slower than my DA40 & DA21 which really are very fast, and about the same speed as my DA70. It's certainly faster than my 50-135, but then what isn't
03-17-2011, 01:02 AM   #6
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from personal experience, I don't think the AF will be slow on K-7/5 bodies but as paperbag wrote, it may be bit of hit and miss.
03-17-2011, 03:20 AM   #7
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First of all thank you all for your responses.


QuoteOriginally posted by hcc Quote
I do not have the 35mm but I have the FA31 mm f1.8. I can compare it with my Voigtlander 58mm f1.4 and my Tamron 90mm f2.8.

The FA31mm f1.8 is doing very well in low-light. It is certainly fast, almost as fast my Voigtlander (f1.4). My FA31mm is definitely much faster than my tammy f2.8.

I would expect that the FA31mm be quite faster than the 35mm f2.4.

Hope that the comment will help.
well thanks for sharing your experience. however I do not know what to make of it since I never used or even seen any voigtlanders in use.

QuoteOriginally posted by Wheatfield Quote
The 31 is better, but not by an astonishing margin.

Woops, I read that as DA35, not DAL.
Forget whatever you read from me.
so.. if it's better not by astonishing amount than the da35 f/2.8 hmm.. ok, i'll have that in mind..

QuoteOriginally posted by paperbag846 Quote
AF will likely be more hit and miss in low light compared with the DAL because of the wider aperture, which results in lower contrast that can be taxing on the AF system in low light.

Whether it will be substantially different though, I cannot say. It would likely be just fine, however moderate-aperture lenses like the DAL tend to be the fastest in the AF department.
well that doesn't mean that i'll be shooting at 1.8. I might be shooting at f/2 or f/2.2.. so since the FL of 31 is a bit wider the focal plane will be somewhere the same.

QuoteOriginally posted by twitch Quote
I think you will struggle to find someone who owns the DAL35 and the FA31. If someone owns the FA31 why would they buy the DAL35, and if someone had the budget to only buy a DAL35 a couple of months ago, how many would have found $1k so soon for a FA31.

My 2cents, as I own the FA31, is that I haven't noticed it to have slow AF at all. My gut feelking is that it is slower than my DA40 & DA21 which really are very fast, and about the same speed as my DA70. It's certainly faster than my 50-135, but then what isn't
hmm.. I guess I'll have to test DA70 first to find out the speed of 31mm DA70 is much easier to obtain here, where I live. I do believe there is someone who awns both. I might be wrong but.. Hin's blog that guy I think he has both of them..

Hin's Tech Corner

QuoteOriginally posted by axl Quote
from personal experience, I don't think the AF will be slow on K-7/5 bodies but as paperbag wrote, it may be bit of hit and miss.
I use Kr, and for not being hit and miss I will not use f/1.8 i'd close it a little.

thanks again everyone, for your input, i'll keep on researching.
03-17-2011, 04:24 AM   #8
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You should not be dissuaded from trying the FA 31 because of AF!

Stopping the lens down might help sometimes, might not help sometimes. Since the camera focuses wide open, stopping the lens down won't speed the lens up.

03-17-2011, 04:27 AM   #9
hcc
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QuoteOriginally posted by Mystic Quote
well thanks for sharing your experience. however I do not know what to make of it since I never used or even seen any voigtlanders in use.
Maybe I was not clear enough. I try again. In low light, the speed of your lens will be linked with the lens aperture. The larger the aperture, the more light goes into the sensor and the faster the lens. A large aperture means a low f. Hence a f1.4 lens will be faster than a f1.8 lens, itslef faster than a f2.4 lens, everything else being equal.

In other words, my comments were related to the lens aperture rather than the lens brand itself. The FA31mm is a f1.8. When shooting in low light at full aperture (f1.8), it will be faster (or can be used with a faster shutter speed) than a lens set at f2.8.

Hope that the comment will help...
03-17-2011, 04:32 AM   #10
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QuoteOriginally posted by hcc Quote
Maybe I was not clear enough. ...
He's asking about autofocus speed, not actual lens speed.
03-17-2011, 08:18 PM   #11
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AF speed? DA35/2.4
03-18-2011, 04:38 AM   #12
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QuoteOriginally posted by VaughnA Quote
He's asking about autofocus speed, not actual lens speed.
yes, you are right . Thanks

QuoteOriginally posted by Pentaxor Quote
AF speed? DA35/2.4
what do you mean? is AF speed of DAL35/24 is quick or what?
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