What crop lens is most like the FA 31 on Full Frame?

**UncleVanya** · 01-29-2019, 05:56 PM - **1 Like**

Originally posted by Sandy Hancock

Just get the DA21 Brad

Thanks Sandy. Did you ever shoot the DA 20-40? That lens is quite fun for me.

hcc · 01-29-2019, 06:09 PM - **1 Like**

I will share here another take. Use the FA31mm on a APS-C camera body. The field of view is very interesting, almost 1:1 with human eyesight. And the colour rendering of the FA31mm is superb. Try it first, before considering another lens on APS-C (cropped) body.

More generally, I shoot APS-C (K-7, K-01, K-3) and I love some FF lenses, like the FA31mm and Fa77mm, on my cameras.

My 5 cents.

Wheatfield · 01-29-2019, 06:23 PM

Originally posted by UncleVanya

OK - odd question and mostly just a fun way to talk about lenses. Recently I used the FA 31 on a loaner K-1. I really liked the perspective and of course the 31 is a special lens in many ways particularly on FF. So which of the choices out there for Crop gives the most FA 31 on FF like experience on crop? The lens need not be a crop lens - but what combination works best to emulate the perspective and some of the special mojo of the FA 31?

These came to my mind immediately:
DA 20-40
DA 21

I'm curious what others think. I have never shot the DA 21 so I have only the DA 20-40 to compare and I'm not sure I find any fault with it but it didn't seem as "right" as the FA 31.

(It is possible this is a fools errand..)

The 21 comes as close as possible as far as field of view goes, but the 21 is not in the same league as the 31. The Fuji 23/1.4 is closer in terms of quality (it's an awesome lens).

normhead · 01-29-2019, 06:37 PM - **2 Likes**

Originally posted by Sandy Hancock

Just get the DA21 Brad

No kidding, you can only waste so much time analyzing.

Sandy Hancock · 01-29-2019, 06:53 PM - **1 Like**

Originally posted by UncleVanya

Thanks Sandy. Did you ever shoot the DA 20-40? That lens is quite fun for me.

I really liked the look and the handling of the 20-40, but my copy was very weak at the wide end and I found the limited zoom range a bit frustrating. I returned it and never felt the need to get another copy.

On the other hand, the DA21 is one of the main reasons I keep a crop system.

**UncleVanya** · 01-29-2019, 08:15 PM

Originally posted by Sandy Hancock

I really liked the look and the handling of the 20-40, but my copy was very weak at the wide end and I found the limited zoom range a bit frustrating. I returned it and never felt the need to get another copy.

On the other hand, the DA21 is one of the main reasons I keep a crop system.

Thanks. That's very helpful.

**Ash** · 01-29-2019, 08:31 PM

Originally posted by clackers

But he wants to emulate the FA31 field of view on APS-C, Ash, a wide angle rather than normal. He hired a K-1, remember.

Yes, I only posted that to show how different lenses even very similar in specs can render images differently. A bit of a digression, I admit.

I agree with Sandy. The 21 is superb.

**clackers** · 01-29-2019, 09:07 PM

Originally posted by Ash

Yes, I only posted that to show how different lenses even very similar in specs can render images differently. A bit of a digression, I admit.

I agree with Sandy. The 21 is superb.

Yeah, it's not the 31 - which is bigger than the FA35 for instance. The FA35 is more the size of what we imagine a Limited to be, with its 49mm filter size.

But with its odd focal length the 21 must have been designed to recreate the FA31 on 35mm field of view. I own it but don't think its similar in other ways, but by making it f3.2 instead of f1.8, it's become a pancake, great for street photography.

**Ash** · 01-29-2019, 10:17 PM

Originally posted by clackers

Yeah, it's not the 31 - which is bigger than the FA35 for instance. The FA35 is more the size of what we imagine a Limited to be, with its 49mm filter size.

But with its odd focal length the 21 must have been designed to recreate the FA31 on 35mm field of view. I own it but don't think its similar in other ways, but by making it f3.2 instead of f1.8, it's become a pancake, great for street photography.

Spot on. Form factor ahead of speed. That's okay in most situations. I find it hard to believe one needs f/1.8 for a 21mm lens often, but on FF, it just seems to make sense to have a 31 with f/1.8 capability. Don't know what makes me think that way other than speed is a virtue on larger formats. The 21 renders images beautifully nonetheless.

Ajax156 · 01-29-2019, 11:54 PM

My vote for the DA21 also - great lens.

grispie · 01-30-2019, 01:35 AM

Originally posted by hcc

I will share here another take. Use the FA31mm on a APS-C camera body. The field of view is very interesting, almost 1:1 with human eyesight.

I agree, i like the 31 on apsc. normal view, albeit a bit wider. Quite interesting..

just a thought: what about the fa24 f2?

**clackers** · 01-30-2019, 02:07 AM

Originally posted by grispie

I agree, i like the 31 on apsc. normal view, albeit a bit wider. Quite interesting..

just a thought: what about the fa24 f2?

24mm f1.4 is more like a 31mm f1.8 at the same distance from the subject. I have the Samyang, but of course it's manual focus.

**Ash** · 01-30-2019, 02:29 AM

Originally posted by clackers

24mm f1.4 is more like a 31mm f1.8 at the same distance from the subject. I have the Samyang, but of course it's manual focus.

Unfortunately that means (to achieve equivalence) you have to invest in (typically) more expensive, faster and larger lenses on APS-C to recreate the same capabilities as you would on FF. It would certainly be hard to make this happen for the already fast FF lenses like the 77/1.8, 85/1.4 and 50/1.4

**robgski** · 01-30-2019, 03:23 AM

Originally posted by Sandy Hancock

On the other hand, the DA21 is one of the main reasons I keep a crop system.

That is true for you, me and a whole pack of Pentaxians, as the photos in this thread demonstrate

normhead · 01-30-2019, 06:26 AM

The 21 and 40XS go into a pocketable Pelican case. Two primes for tripping, to go with the 18-135 and 55-300 PLM.

01-29-2019, 08:31 PM	#22
Ash Loyal Site Supporter Join Date: Mar 2007 Location: Toowoomba, Queensland Photos: Gallery \| Albums Posts: 23,920	What crop lens is most like the FA 31 on Full Frame? Originally posted by clackers But he wants to emulate the FA31 field of view on APS-C, Ash, a wide angle rather than normal. He hired a K-1, remember. Yes, I only posted that to show how different lenses even very similar in specs can render images differently. A bit of a digression, I admit. I agree with Sandy. The 21 is superb.

01-29-2019, 09:07 PM	#23
clackers Otis Memorial Pentaxian Join Date: Jul 2013 Location: Melbourne Photos: Albums Posts: 16,397	Originally posted by Ash Yes, I only posted that to show how different lenses even very similar in specs can render images differently. A bit of a digression, I admit. I agree with Sandy. The 21 is superb. Yeah, it's not the 31 - which is bigger than the FA35 for instance. The FA35 is more the size of what we imagine a Limited to be, with its 49mm filter size. But with its odd focal length the 21 must have been designed to recreate the FA31 on 35mm field of view. I own it but don't think its similar in other ways, but by making it f3.2 instead of f1.8, it's become a pancake, great for street photography. Last edited by clackers; 01-29-2019 at 09:50 PM.

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01-29-2019, 05:56 PM - 1 Like	#16
UncleVanya Loyal Site Supporter Join Date: Jul 2014 Photos: Gallery \| Albums Posts: 28,401 Original Poster	Originally posted by Sandy Hancock Just get the DA21 Brad Thanks Sandy. Did you ever shoot the DA 20-40? That lens is quite fun for me.

01-29-2019, 06:09 PM - 1 Like	#17
hcc Pentaxian Join Date: Nov 2009 Location: Brisbane, Australia Photos: Gallery \| Albums Posts: 4,002	I will share here another take. Use the FA31mm on a APS-C camera body. The field of view is very interesting, almost 1:1 with human eyesight. And the colour rendering of the FA31mm is superb. Try it first, before considering another lens on APS-C (cropped) body. More generally, I shoot APS-C (K-7, K-01, K-3) and I love some FF lenses, like the FA31mm and Fa77mm, on my cameras. My 5 cents.

01-29-2019, 06:23 PM	#18
Wheatfield Moderator Join Date: Apr 2008 Location: The wheatfields of Canada Posts: 15,981	Originally posted by UncleVanya OK - odd question and mostly just a fun way to talk about lenses. Recently I used the FA 31 on a loaner K-1. I really liked the perspective and of course the 31 is a special lens in many ways particularly on FF. So which of the choices out there for Crop gives the most FA 31 on FF like experience on crop? The lens need not be a crop lens - but what combination works best to emulate the perspective and some of the special mojo of the FA 31? These came to my mind immediately: DA 20-40 DA 21 I'm curious what others think. I have never shot the DA 21 so I have only the DA 20-40 to compare and I'm not sure I find any fault with it but it didn't seem as "right" as the FA 31. (It is possible this is a fools errand..) The 21 comes as close as possible as far as field of view goes, but the 21 is not in the same league as the 31. The Fuji 23/1.4 is closer in terms of quality (it's an awesome lens).

01-29-2019, 06:37 PM - 2 Likes	#19
normhead Pentaxian Join Date: Jun 2007 Location: Near Algonquin Park Photos: Gallery \| Albums Posts: 40,451	Originally posted by Sandy Hancock Just get the DA21 Brad No kidding, you can only waste so much time analyzing.

01-29-2019, 06:53 PM - 1 Like	#20
Sandy Hancock Moderator Site Supporter Join Date: Feb 2012 Location: Adelaide Hills, South Australia Photos: Gallery \| Albums Posts: 11,272	Originally posted by UncleVanya Thanks Sandy. Did you ever shoot the DA 20-40? That lens is quite fun for me. I really liked the look and the handling of the 20-40, but my copy was very weak at the wide end and I found the limited zoom range a bit frustrating. I returned it and never felt the need to get another copy. On the other hand, the DA21 is one of the main reasons I keep a crop system.

01-29-2019, 08:15 PM	#21
UncleVanya Loyal Site Supporter Join Date: Jul 2014 Photos: Gallery \| Albums Posts: 28,401 Original Poster	Originally posted by Sandy Hancock I really liked the look and the handling of the 20-40, but my copy was very weak at the wide end and I found the limited zoom range a bit frustrating. I returned it and never felt the need to get another copy. On the other hand, the DA21 is one of the main reasons I keep a crop system. Thanks. That's very helpful.

01-29-2019, 10:17 PM	#24
Ash Loyal Site Supporter Join Date: Mar 2007 Location: Toowoomba, Queensland Photos: Gallery \| Albums Posts: 23,920	Originally posted by clackers Yeah, it's not the 31 - which is bigger than the FA35 for instance. The FA35 is more the size of what we imagine a Limited to be, with its 49mm filter size. But with its odd focal length the 21 must have been designed to recreate the FA31 on 35mm field of view. I own it but don't think its similar in other ways, but by making it f3.2 instead of f1.8, it's become a pancake, great for street photography. Spot on. Form factor ahead of speed. That's okay in most situations. I find it hard to believe one needs f/1.8 for a 21mm lens often, but on FF, it just seems to make sense to have a 31 with f/1.8 capability. Don't know what makes me think that way other than speed is a virtue on larger formats. The 21 renders images beautifully nonetheless.

01-29-2019, 11:54 PM	#25
Ajax156 Junior Member Join Date: Jan 2019 Posts: 45	My vote for the DA21 also - great lens.

01-30-2019, 01:35 AM	#26
grispie Veteran Member Join Date: Feb 2013 Posts: 1,199	Originally posted by hcc I will share here another take. Use the FA31mm on a APS-C camera body. The field of view is very interesting, almost 1:1 with human eyesight. I agree, i like the 31 on apsc. normal view, albeit a bit wider. Quite interesting.. just a thought: what about the fa24 f2?

01-30-2019, 02:07 AM	#27
clackers Otis Memorial Pentaxian Join Date: Jul 2013 Location: Melbourne Photos: Albums Posts: 16,397	Originally posted by grispie I agree, i like the 31 on apsc. normal view, albeit a bit wider. Quite interesting.. just a thought: what about the fa24 f2? 24mm f1.4 is more like a 31mm f1.8 at the same distance from the subject. I have the Samyang, but of course it's manual focus.

01-30-2019, 02:29 AM	#28
Ash Loyal Site Supporter Join Date: Mar 2007 Location: Toowoomba, Queensland Photos: Gallery \| Albums Posts: 23,920	Originally posted by clackers 24mm f1.4 is more like a 31mm f1.8 at the same distance from the subject. I have the Samyang, but of course it's manual focus. Unfortunately that means (to achieve equivalence) you have to invest in (typically) more expensive, faster and larger lenses on APS-C to recreate the same capabilities as you would on FF. It would certainly be hard to make this happen for the already fast FF lenses like the 77/1.8, 85/1.4 and 50/1.4

01-30-2019, 03:23 AM	#29
robgski Loyal Site Supporter Join Date: Nov 2012 Location: Shenandoah Valley, Virginia Photos: Gallery \| Albums Posts: 8,796	Originally posted by Sandy Hancock On the other hand, the DA21 is one of the main reasons I keep a crop system. That is true for you, me and a whole pack of Pentaxians, as the photos in this thread demonstrate

01-30-2019, 06:26 AM	#30
normhead Pentaxian Join Date: Jun 2007 Location: Near Algonquin Park Photos: Gallery \| Albums Posts: 40,451	The 21 and 40XS go into a pocketable Pelican case. Two primes for tripping, to go with the 18-135 and 55-300 PLM.