HD Pentax-D FA 21mm f/2.4 ED DC WR Limited Sample Photos, Real-world Use, Specs | Round Glass Review

[@rosswaugh1254]

Thank you for this review David, As always helpful and very nice to see the range of images this lens can produce. The lens is on my list to buy,

[@DavidHancock]

Thank you, Ross! It's a great lens, too. Definitely worth looking at seriously.

[@matthewp7428]

I picked this lens up a couple months ago. Your review is on point. I've been really impressed with it.

[@DavidHancock]

Thank you!

[@Beckkerable]

I really hesitated to buy this lens for the focal length was included in my D FA 15 - 30 mm 2.8. But I never did regret the choice. Outstandig lens. Very strong at short distance - with wide background. - By the way: Very impressive footage provided for the review my friend!

[@DavidHancock]

Thank you! Yeah, this is an amazing lens.

[@dneira29]

Do you think it serves as a replacement for your 15-30. I have the 15-30 but it’s big and heavy. How does the AF compare between the 2 lenses?

[@Beckkerable]

I stick to the 15-30 mm zoom for the range is so atttractive. 15 mm - no doubt - is more efficient than 21 mm. These 6 mm mean a lot. The AF of the new limited 21 mm is definitely not faster than the elder zoom. In other words: The AF of the 15-30 mm is pretty good.@@dneira29

[@Skipsul]

You are right vis. the motor and going past infinity, but there is one other technical use. The ability to go past infinity allows the AF to compensate when infinity itself (in terms of the lens) shifts due to material expansion or contraction due to temperature. These shifts are infinitesimal, usually, but with high resolutions and pixel peepers, they want perfection. As a frequent manual focuser myself, it drives me batty though.

[@DavidHancock]

Oh that's a great point I hadn't considered. I think of that as a long lens and telescope issue. It honestly never occurred to me that temperature can affect shorter lenses. Thank you!

[@thomastaylor9237]

Thank you for the review. The images are spectacular. If I could only keep one lens for my K-1, the DFA 21mm Limited would be it.

[@DavidHancock]

Thank you! :D

[@TheOffertonhatter]

Just to let you know, the lens will work on all current Pentax bodies (K-1II, K-3III, K3III mono, K-70, KP and KF) without firmware updates, and the K-1, K-3, K-3II, K-S1, K-S2 with appropriate firmware update. Lovely images from the lens by the way.

[@DavidHancock]

Thank you!

[@SabahHamad-b4b]

Thank you David, honest review

[@DavidHancock]

Thank you!

[@l.nauwelaerts195]

Thank you for this review. The question is not if but rather when I will buy it. Were you able to test it on K3 platform as well? Could it do as a "31 limited equivalent" on a crop body (with different max aperture, of course) in your opinion?

[@DavidHancock]

You know, I thought I had used this on the K-3, but maybe not. Since it looks like I didn't indicate the format on any of the images, they all would have been full frame. At the front of the specs section, there should be an image that shows the APS-C image area, though.

[@olafpreu266]

I can tell the lens does work with the Monster Adapter on the Sony a7VI with autofocus !!!

[@DavidHancock]

That's good to hear. I must have a faulty Monster adapter because on my A7 IV it works with nothing at all and often doesn't even stop-down the aperture on older FA lenses.

[@olafpreu266]

@@DavidHancock maybe you have to update the adapter! I just did it again last week, I believe it is softwareversion 5 now. There should be an instruction on the homepage of the adapter-firm.

[@DavidHancock]

@@olafpreu266 I didn't realize I can do that. I didn't see a port on it anywhere. But thank you! I'll see what I can do for that this weekend.

[@thetimfilm0812]

So this would be a true 31 for the k3mkiii. Have any thoughts using it on the k3?

[@DavidHancock]

Well, it's a true 31mm on any camera, the K-3 III BW is a crop-sensor camera so this would have an angle of view equivalent to 46.5mm-ish. For APS-C, this is an awesome standard lens.

[@walterhall9682]

What is round glass? I would like to know

[@DavidHancock]

@@walterhall9682 it's just a name based on the shape of the glass inside of lenses.

[@DcgK1000]

What about the AF accuracy

[@DavidHancock]

@@DcgK1000 depends on your camera, AF settings, lighting conditions, subject, and a handful of other variables. That said, it was excellent for everything I did.