RiceHigh's Pentax Blog: FA 31/1.8 Vs FA 35/2 Vs DAL 35/2.4 Shootout (Two Picture Sets)

Tuesday, March 08, 2011

FA 31/1.8 Vs FA 35/2 Vs DAL 35/2.4 Shootout (Two Picture Sets)

See: http://pentax.org.pl/viewtopic.php?p=765767

(or Google-translated English Page Here)

All posted images are 100% crops of the original photos, which were taken with a K-7. For (much) easier viewing and for better measurbation, I've tabulated the results as below. Just click to open each of the full crops in a new window/tab:-

Aperture (f-number)	FA 31mm F1.8 Limited	FA 35mm F2	DA(L) 35mm F2.4
1.8		Nil	Nil
2			Nil
2.5/2.4
2.8
4
1.8		Nil	Nil
2			Nil
2.5/2.4
2.8
4

I have two quick observations from the above:-

1. The FA31 Limited has the worst focusing accuracy. It has a great tendency of out focusing at larger apertures but yet at 2.4 and beyond, the focusing errors can still be seen;

2. The FA35 particularly has a cooler tone than the other two.

You take now for other findings! Just feel free to give your inputs by writing a comment here, to this Blog entry, if you really have some to add. :-)

Comments (17)

Logging you in...

Dashboard | Edit profile | Logout

Logged in as

+8 Vote up Vote down

Frederik9111 · 734 weeks ago

Your first finding does not seem to be true for the second set op pictures...

Second, you didn't mention the use of a tripod. So you nor your subject can be considered as 'motionless'. So any statement about AF-accuracy is meaningless in my opinion (DOF is as thin as a sheet of paper).

4 replies · active 734 weeks ago

-9 Vote up Vote down

RiceHigh 110p · 734 weeks ago

What is "a sheet of paper" which is nearly 30cm thick? :-o

Go to: http://www.dofmaster.com/dofjs.html

Input K-5 or K-7, 31mm, f/1.8, focus a near subject at 2m, say for example!

+7 Vote up Vote down

Frederik9111 · 734 weeks ago

Impossible that the focus distance in the second set was 2 meter. In the F1.8 shot you can see that the DOF is only 3-4 cm (or the lady has an extremely large head). So probably closer to one meter (which would be consistent with DOFmaster, and the 700*700 crops of your K-7)

-9 Vote up Vote down

RiceHigh 110p · 734 weeks ago

The OP already said that those posted images are 100% crops of the original photos in the very beginning. He has lately supplemented that the shots were taken at a distance from 1 to 1.5 meter, from his memory.

+8 Vote up Vote down

Frederik9111 · 734 weeks ago

Et voilà! So like I said: pretty useless test.

+4 Vote up Vote down

want_fullframe · 732 weeks ago

RH, what do you think of the FA 31mm? Too expensive now? What do you like for Pentax at the wide end? What about the FA* 24mm?

5 replies · active 726 weeks ago

-3 Vote up Vote down

RiceHigh 110p · 732 weeks ago

The FA 31 is good as long as you can find one without any optical mis-alignment defect (in general early Japanese production is better). However, this lens tends to be mis-focus on Pentax DSLR bodies. So, this would be another headache. For more details, see:-
http://ricehigh.blogspot.com/2010/03/fa-31-limite...

With the new low-cost DAL35, actually there is no strong reason to get the FA 31 anymore, frankly. Do note that the FA31 is much bigger and heavier, too. But however, the FA31 is only just less than 1 stop faster and both lenses cover full (135) frame.

+3 Vote up Vote down

want_fullframe · 732 weeks ago

Thanks, For $1299.95, there is no room for defects IMO.

What about the FA* 24mm f2? That's the only FA* that's still easy to get. Does it render yellow and have bad corners on FF? (I still use film FF as well as digital).

PS: I tried to access your favorite lenses table(from way back), but it goes to a dead link.

-5 Vote up Vote down

RiceHigh 110p · 732 weeks ago

I have very limited experience with the FA*24 myself. But however, from the larger samples I inspected, I found that its corner performance is weak on Pentax DSLRs.

The colour rendition and other optical performance aspects of it should be good enough, as it is a FA*.

As for my rating table on various Pentax AF lenses, here is the updated one:-

http://ricehigh.blogspot.com/2010/03/ricehighs-su...

-1 Vote up Vote down

Chris · 726 weeks ago

@want_fullframe: I paid $1000 for my FA31 in Delaware, USA, while travelling. The lens is assembled in Vietnam and has superior image quality, especially sharpness throughout the frame, compared to any of my other lenses. This is of course a subjective statement and not a result of scientific measurements.

@Rice High: please help me with this: how can a lens "tend to mis-focus". Isn't focusing PURELY the job of the body? Or wait, I know: this is about the missing f/2 focus sensor you were talking about, right?

0 Vote up Vote down

RiceHigh 110p · 726 weeks ago

It's all about the spherical aberration (plus some factory misalignments could make it worse), see my this recent article for more technical details:-

http://ricehigh.blogspot.com/2011/04/again-why-f2...

+10 Vote up Vote down

Tomand · 726 weeks ago

Why you use somebody work probably without permission? You simply don't understand a word in Polish, so what's the point of using these photos? You don't know anything about conditions during taking these photos so how you can draw conclusions?

1 reply · active less than 1 minute ago

-9 Vote up Vote down

RiceHigh 110p · 726 weeks ago

Why you *read* somebody's work and "use" the comments from others without our permissions then?

-1 Vote up Vote down

Jason · 541 weeks ago

Your FA31 Limited focusing accuracy's comment is very truth. it is a kind of disappoint for me after had been using it.

You might want to compare f28 with fa31 too. Another close call but used f28 is like 5 times cheaper than fa31!

Some fa31 user likes to say that, fa31 has it pixeldust (whatever that mean!) or it got its magic.
Look at fa31 price? To me, its performance is “average” for a lens that expensive. zero magic.
But look at FA35 price, and look at how close it can get to a 3 times more expensive lens? Now that’s a real magic to me.

3 replies · active 541 weeks ago

0 Vote up Vote down

fa85 is best · 541 weeks ago

same is said about fa77. FA77 is probably more hyped than FA31. Yet the FA*85 is much better. FA77 is compact however.

another best lens is FA80-200 f2.8. amazing.

+1 Vote up Vote down

RiceHigh 110p · 541 weeks ago

I have both FA*85 and FA77 and have to say the FA*85 must be a better lens. The FA77 is not bad, nonetheless, and it is easy to carry. Both have quite obvious purple fringing when used on particular Pentax DSLR bodies with various different sensors. The DA70 has the least PF, but optical quality wise it has little character of its own, on the other hand.

+1 Vote up Vote down

RiceHigh 110p · 541 weeks ago

I once owned a MIJ FA35 and still now own a MIJ FA28 and a MIV DA35/2.4, I think the FA28 is the best lens amongst three. Whilst the DA35 is improved for digital, its IQ is not as exciting as it should be, especially when it is compared to the FA35 when both are stopped down.

Post a new comment

Comment as a Guest, or login:

Tweet this comment

RiceHigh's Pentax Blog

Tuesday, March 08, 2011

FA 31/1.8 Vs FA 35/2 Vs DAL 35/2.4 Shootout (Two Picture Sets)

Forgot password?

Comments (17)

Post a new comment

Reference Links (by Others)

My Technical Articles (Latest First)