[Eriks]

Hi!

Any experiences using the FA 31mm on a K200D?

I have the lens, and is considering the camera.
All advices/thoughts are most welcome.

[k100d]

i'd imagine it would perform like the FA31 on the K10D, in otherwords excellent

[vizjerei]

Simon, I thought you have upgraded to K20D, no?

[k100d]

Simon, I thought you have upgraded to K20D, no?

thought about it ... will wait till after Photokina

[roentarre]

Fa 31mm ltd typically underexposes slightly more comparing to other lenses. Its bokeh is really prone to noise underexposed when the lens is used wide open.

Most of the time, this lens does not perform any way different from most lens line up. On occasions, it has interesting micro contrast that "pop" the subjects and it is reliable stopping down in the corner. On k200d sensor, the main issue with Fa 31 mm ltd is noise in the bokeh department.

[jacksonpritt]

Hey guys!

I'm trying to decide between the Pentax-DA 35mm and the Pentax-FA 31mm, and I was wondering if any of you had any suggestions or advice. I really like working with primes, and I love my FA 50mm ƒ1.4, but I'd like to get something a little sharper, and that lets me get a little closer to my subject.

Which of these lenses would you guys pick, if you had to choose one?


Pentax-DA 35mm ƒ2.8
Pentax Lens Review Database - 35mm F2.8 Limited Macro

Pentax-FA 31mm ƒ1.8
Pentax Lens Review Database - 31mm F1.8 AL Limited


Also, are these lengths the TRUE lengths of the lenses, or are they the lengths on a crop sensor? I know the K10D has a 1.5 crop factor (so my FA 50mm is really like a 75mm on film), so I was wondering if these lenses are 35mm & 31mm for film (52.5mm & 46.5 on crop) or if the 35mm & 31mm measurements take into account the crop factor.


THANKS!!!

[Aegon]

These are 31 and 35mm on film.

Technically, they are 31 and 35mm on digital too, but they act like 47 and 53mm on digital.

For macro work, the 35 is better. For portraiture or low light, the 31 is better. I've never used either, but I think this is a really safe place to start.

Buy them both and be happy.

[Marc Sabatella]

Also, are these lengths the TRUE lengths of the lenses, or are they the lengths on a crop sensor?

*Any* lens you ever see sold for *any* DSLR will list its true focal length. If you are interested in figuring out what the equivalent focal length length would be on film, you have to apply the crop factor yourself.

[jacksonpritt]

*Any* lens you ever see sold for *any* DSLR will list its true focal length. If you are interested in figuring out what the equivalent focal length length would be on film, you have to apply the crop factor yourself.

So are you saying that any lens, regardless of who manufactured it or what format it was manufactured for, will always have a 1.5 crop multiplier on a DSLR with a crop sensor?

What about lenses that are specifically designed for cameras with crop sensors? Are they labeled the same way?

Sorry about being confused about such a basic issue, but people in the community I frequent the most are split about 50/50 between film & DSLR, and this gets pretty confusing.

[benplaut]

I had the exact same question when I was trying to figure it all out. Focal length is a measure of the lens, not the camera it attaches to. Notice that on a point and shoot, the lens will be "7.2-20" or similar, which is what the lens will be on any camera, regardless of the size image it can project. a cropped 18-55 on a cropped camera will behave exactly the same as a full frame 18-55 on a cropped camera--it's just that the sensor onto which the image is projected is smaller than on film.

[jsherman999]

.


You can find some further discussion and image examples from both lenses in
---> this thread.

Of course, you should own both , but I'd have to say the DA 35ltd macro has more bang for the buck.

[k100d]

pentax has a tonne of choices b/n 30 and 50mm. i'm assuming you've done your research on the FA35, DA40 and excluded those too?

i have the FA31 and it's very sharp with very pleasant bokeh for a wide lens. however it is no doubt overpriced.
the ability to go to f1.8 is really handy tho, the image is still very good but at 2.8 it's already excellent

[roentarre]

It may be better to start using kit lens for 2 years before considering any other lenses.

[benplaut]

It may be better to start using kit lens for 2 years before considering any other lenses.

I disagree... maybe for $$$, yes, but exclusively using a prime for an extended period of time really does make you a better photographer. Your framing must be more creative, you have to move around more, and there's more possibility for experimenting with DoF.

For me, it was a full manual Nikon 50/1.8... 4 months with it and I never wanted to use a zoom again

[MrA]

So are you saying that any lens, regardless of who manufactured it or what format it was manufactured for, will always have a 1.5 crop multiplier on a DSLR with a crop sensor?

What about lenses that are specifically designed for cameras with crop sensors? Are they labeled the same way?

Yes and Yes. Just multiply everything by x1.5 to see it's equivalent in 'old money' when mounted on a Pentax DSLR.

That is why lense specifically designed for crop sensors are much shorter than the shortest available for film cameras. Those 10-20mm, 11-16mm, 14mm, lenses, for instance.