55mm ??

Anybody got their 55mm da* yet ? Rumour has it that SRS have shipped their initial allocation. Anyone on here lucky enough to be in that group ?

If so, Samples & review please

Hi All

SRS sent me an e-mail Monday, got back to them Tuesday and my DA*55 arrived this morning (Wednesday) just as I was leaving for work. Excellent service as always.

Cameras not allowed in work so I've only been able to take a few wallpaper shots at home with flash this evening.

First impressions.
A really light lens that looks and feels good; and unlike some smaller lenses is not dwarfed by a K10D or K20D, not surprising as its about the same size as a DA18-55.
Bright red SDM on lens designation on the barrel reinforces the fact that this is Pentax's second KAF3 mount lens - fully backward compatible with KAF2 mount but manual focus only with KAF mount (eg ist* DS).
In the box there was a Pentax DA lens manual (first I have had despite this being my 8th DA/DA* lens bought new). Manual is fully up to date including the (almost mythical) DA*60-250.

Focusing (centre point spot focusing).
My copy tends to hunt a bit in the low light of a 100W bulb and I needed to ensure there was some detail under the focus point in order for a good focus.
Given that this is an f1.4 lens I was surprised, especially as my DA*16-50 (set at 50mm) and DA*50-135 (set at 55mm) which are both f2.8 locked on their focus immediately.
I fitted an AF540 flash, turned the room light off in order to 'force' the focus assist beam to activate then the focus was SDM quick and accurate. Clearly this lens needs a higher contrast target to focus on than some other DA* lenses.

Exposure
Using flash the corners of the frame were equaly exposed as the centre throughout the full f stop range, ie no vignetting at f1.4.
NB with popup flash no shadow cast by lens even with lens hood fitted.



Sharpness
In the following the first picture for each aperture is 100% crop from the middle and the second a 100% crop from the corner of each frame.
f1.4





f2.0





f2.8





f4.0





f5.6





f8.0





f11





f16





f22





These are unsharpened JPG. In my opinion the at the centre of the frame the images were sharp from f2.0 and at the corners from f2.8.
That doesn't indicate anything wrong as I consider this to be within the range of normal softening of any lens at maximum apertures, nothing seen at f1.4 that a little sharpening in Photoshop won't cure

Future Proof?
with rumours of K30D having a APS-H sensor or a 23.5mm square sensor I decided to put this on one of my LXs to see how compatible the lens would be with larger sensors.
DA*55 NO vignetting on LX therefore would be usable on APS-H, square 23.5, 36x24 as well as APS-C.
Just for fun I also did the other DA* lenses
DA*300 NO vignetting on LX
DA*200 NO vignetting on LX
DA*50-135 corners of LX viewfinder were black - however I do not think this would effect APS-H or 23.5 square sensors
DA*16-50 at 16mm vignetting of corners meets in the middle of the short side of the viewfinder, this reduces as the lens is zoomed to 50mm. I visualy estimate there may be some vignetting with this lens if used on APS-H or 23.5mm square sensors.
As LX cannot control lens aperture and there are no aperture rings on DA* lenses the above comments apply to max aperture for each lens and it would be anticipated that vignetting would reduce as the aperture gets smaller.

Summary
Images are evenly exposed with no vignetting.
very slight pincushion distortion.
focus requires stronger contrast target than other DA* lenses - a bit disappointing as f1.4 should be better in low light.
Altogether a worthy addition to the DA* range and I look forward to taking some 'real' pictures with it.

Good luck
Bob

Thanks for the time & effort Bob.
It will be interesting to see how this performs as a portrait lens. I'm sure we'll see some examples trickling through on various sites shortly.

You've got a fair few bits of glass there. Remind me never to "caddy" for you !

You've just made another Bob highly jealous!

I appreciate the time you've taken for this quick review; i've been scouting the Web for a few days now to see any reviews of this new lens and found nothing - thanks a lot Bob!

I also concur with RR (and pardon the alliteration)- that's a fair few fine pieces of glass you have there!

Does anyone know where I can find some sample images that illustrate the bokeh from this lens ?

http://dc.watch.impress.co.jp/cda/lens_review/2009/02/16/10203.html

nice work Bob,

Very interesting that essentially the entire DA* range can handle a bigger sensor than it is currently marketed at. Pentax are clearly keeping their options open, very wise in my opinion.

Edit: I've just decided that what I originally wrote is actually wrong, appologies

Thanks Peter. Will try & find some more examples but I'm currently leaning toward the creamier bokeh of the Sigma 50mm.

I liked the lens when testing it out at SRS yesterday but I had some problems. PF is pronounced wide open but it does disappear by stopping down to F2. Focusing was not accurate enough on my K10 and most shots were OoF. It is too similar to the FA50f1.4 and I don't know wether it is worth the price if I'd be using it stopped down and can get the same shot with my 50-135.

and another review digitalcamerareview.com linky

Still need to read it so you know as much as me now

The review agrees with Tyr, focus off with the K10D and purple fringing wide open. Focus ok with other bodies though (how odd...).

Cheers, Kris.

I'm still wandering if to get it or not over the FA 50.
It's so far as I can see quite a bit sharper wide open and the bokeh is pleasant to my eyes atleast so nothing against the image quality besides the purple fringing wide open but I can live with that.
The focus thing is another matter.
For in the studio it is no problem but for casual shooting it is for me, hopefully there will come an update since on the other models it works good it seems.

edit:
I've readed another review about the 17-70 and it also seems to have some problems with that. The K10D needs some updating it seems to get it to work with thw KAF3 mount as it need to be

Bob you've the lenes for a while now, what do you think of it?
Any other member having the lens for awhile can answer to of course