Hi everybody,

I would like to open up a thread dedicated to one topic:

DA lens on Full Frame: a sticky test shots thread.

This thread shall be dedicated to test shots of a DA lens mounted to a full frame body (e.g., a film camera body). By test shot, I mean shots dedicated to evaluate the performance. Shots of ordinary subjects aren't suitable to this task, normally, and should not be posted. So, these are the rules:

• K mount lens dedicated to the APS-C form factor is used.
• Image is taken full frame 36mm x 24mm.
• Lens hood was removed.
• And ideally, no filter is mounted.
• The aperture used is specified (note that film cameras don't record EXIF...).
• Sample image shows the entire field of view.
• Sample image(s) show(s) corner, border and center performance at 10MP-100% (multiple crops, or single not-resized image).
• The subject is such that resolution and vignetting at the borders can be compared to the center.

The idea behind this thread is obvious: To compile enough data to assess the spectrum of available lenses for a forthcoming full frame DSLR in K mount.

#################################################

Table of results as obtained in this thread (updated regularly):

SMC Pentax-DA primes...

• DA 14mm F2.8: - (clawhammer)
• DA 15mm F4.0: - (Zav)
• DA 21mm F3.2 Limited: - (Boris Liberman)
• DA 35mm F2.4 AL: +++ (aurele ;like FA35/2.0 and no vignetting) (frank)
• DA 35mm F2.8 Limited Macro: 0 (ryno), + (@ 1.15 crop)
• DA 40mm F2.8 Limited: +
• DA* 55mm F1.4 SDM: +++ (aurele)
• DA 70mm F2.4 Limited: +
• D FA Macro 100mm F2.8 WR: +++ (officially specified FF by Pentax)
• DA* 200mm F2.8 ED [IF] SDM: +++? (common belief, but is it true?)
• DA* 300mm F4 ED [IF] SDM: ++ (officially rated "designed for FF" by Pentax patent US7715116)

SMC Pentax-DA zooms...

• DA 10-17mm F3.5-4.5 Fish-Eye ED [IF]: FE, see #59, #61, #94. 10mm: heavy vignette / 14mm: almost no vignette / 17mm ++ (Reps, froeschle, Gooshin)
• DA 12-24mm F4 ED AL [IF]: - (below 16mm, xitek.com), o (at 18mm, architorture), + (at 20mm, architorture), ++ (at 24mm, architorture)
• DA 16-45mm F4: - (below 21mm, Nesster)
• DA* 16-50mm F2.8 ED AL [IF] SDM: - (xitek.com)
• DA 17-70mm F4 AL [IF] SDM: - (KjetilH)
• DA 18-55mm F3.5-5.6 AL: - (at 18mm, Spongefingers; below 23mm, xitek.com)
• DA 18-55mm F3.5-5.6 AL II: missing
• DA 18-250mm F3.5-6.3 ED AL [IF]: - (xitek.com)
• DA 50-200mm ED: -
• DA* 50-135mm F2.8 ED [IF] SDM: - (elho_cid)
• DA* 60-250mm F4 ED [IF] SDM: ++ (officially rated "designed for FF" by Pentax patent US7489452) probably good on full frame but evaluation still missing; the rating is +++ with a baffle modification, + without)
• DA 55-300mm F4-5.8 ED: 0 (+, ++ at tele end, viking79)

Sigma K mount DC...

• Sigma 18-200mm f/3.5-6.3 DC: -
• Sigma 10-20mm f/4-5.6 DC: - (below 14mm, Gooshin)
• ...

Tamron K mount Di-II...

• ...

Overall rating scale:
+++: no significant difference between APS-C and FF corners
++: difference but usable at full aperture with a small loss in corner IQ only
+: usable staring at f/4~f/5.6, with no or a small loss in corner IQ only
o: usable at f/11 or with big loss in corner IQ only
-: not usable

[falconeye]

I have verified that the chromatic aberration in the extreme corners for the DA* 300 is as assumed above:

CA_lat = 4 px = 20 µm.

In the attachment, you find a 100% crop of the extreme corner in B&W and in colour (from an image I found in my archive). The colour image shows green/purple fringing of the exact same size (4 px). I assume the ghosting in the B&W image comes from quite selective colour sensitivities of this particular emulsion.

However, 20µm, when printed on 8 x 12", is only 1.7 dots at 240dpi printing resolution and should be only hardly visible. See for yourself how tiny the surface covered by the corner really is (the inset shows the full image).

So, I am wondering if 20µm CA in the extreme corners of a FF lens really is a bad value. It may just be normal.

Any opinions?

---

Last edited by falconeye; 06-15-2011 at 05:28 AM.

[clawhammer]

Wow, those are some serious tests you've done. Thanks for all the effort!

[falconeye]

Wow, those are some serious tests you've done. Thanks for all the effort!

I think we need it clarified which glass is FF. It is true that it is quite some work to do. But finally we can avoid investing into the wrong direction. And I hope Pentax will not release non-FF glass where it has no benefit.

Please rate this thread if you like it. So maybe, Adam makes it sticky

I also updated my initial posting to contain a summary table of the results obtained so far. Thanks for watching.

[vizjerei]

Thank you falconeye I was thinking about the DA*300, thank you for the testing.

[Pål Jensen]

I reserved the option to upgrade the rating because I don't know yet how a true full frame tele lens does perform in its extreme corners. I will update this page as soon as I know.

It is very common for a 300mm lens and are always there at lenses even longer.

[falconeye]

It is very common for a 300mm lens and are always there at lenses even longer.

Thank You, Pål. I upgraded my rating for the DA*300 to ++ now. I am still looking forward for a test of a FA 300mm lens to really know. I'll let you know my findings.

[falconeye]

Test procedure is as described in post #28.


Fill-factor with the DA 70 test shots: 98.6%

Test shots (red line marks the APS-C image circle):
--
f/2.4:

--
f/5.6:

--
f/11:

(click onto images for full scale 5062 dpi images)

Numerical evaluation (first figures: as read from small charts) (second figures: in LW/PH):

Center (f2.4 / f5.6 / f11): (7 / 7.5 / 7.5) (2800 / 3050 / 3050)
APS-C corner (f2.4 / f5.6 / f11): (6 / 7 / 7) (2400 / 2800 / 2800)
FF corner (f2.4 / f5.6 / f11): (2-3 / 6 / 5) (800-1200 / 2400 / 2000)
FF vignetting (f2.4 / f5.6 / f11): (+ / ++ / +++)

Final verdict:

+

Usable starting at ~f/5.6, with a small loss in corner IQ only.

[falconeye]

Test procedure is as described in post #28.

(Note: in all test shots, in this and previous postings, use a form of exposition/gamma control to make visible all details)


Fill-factor with the DA 35 test shots: 96.1%

Test shots (red line marks the APS-C image circle):
--
f/2.8:

--
f/5.6:

--
f/11:

(click onto images for full scale 5062 dpi images)

Numerical evaluation (first figures: as read from small charts) (second figures: in LW/PH):

Center (f2.8 / f5.6 / f11): (7 / 7 / 7.5) (2900 / 2900 / 3100)
APS-C corner (f2.8 / f5.6 / f11): (6 / 6 / 7) (2500 / 2500 / 2900)
Crop 1.15 corner (f2.8 / f5.6 / f11): (3 / 4 / 5) (1200 / 1700 / 2100)
FF corner (f2.8 / f5.6 / f11): (1.5 / 2 / 2) (600 / 800 / 800)
FF vignetting (f2.8 / f5.6 / f11): (0 / + / +)


At f/2.8, the corner resolution drops to about 50% at the 1.15 crop-factor corner and drops to only 25% at the extreme FF corners. The vignetting is not complete but needs two repeated applications of a max.-strength anti-vignetting filter in Photoshop to be restored.


Final verdict:

0

When used with a 1.15 crop factor:

+

So, on a full-frame body, the DA 35 is usable pretty much like the DA40 lens (because of the slight recommended crop) but does still provide full 1:1 Macro capabilities. Therefore, the DA35 Ltd. stays a strong buy even with a FF body.

[Adam]

Thread copied into the knowledgebase.

[Edvinas]

I can't provide test shots, but believe me DA 17-70 is not usable on 35mm format at any length. I have tried to put it on Pentax film camera and at all lengths I saw vignetting in viewfinder not less than that of DA 16-45 at widest angle.

New DA 55-300 almost OK for 35mm format. Only the very angles of frame are dark. 1.15 crop would be definitely be OK.

[Adam]

Thread re-opened.

[sft]

Wow - that's some serious work you've put into all this thanks very much. I have a bunch of DA lenses, not least of all the DA70 which is my favorite of them, which I had heard (before I had seen this thread) did cover the full 35mm format - however looking at your samples I think it is safe to assume that the performance on a 35mm is definetely not "Limited" quality like it is on the APS-C sensors. Most probably if Pentax do release a FF DSLR - all DA lenses will be cropped (ala Nikon D3) to retain the good IQ even if they are rumored to cover FF like the DA40 & DA70.

I do wonder how the still available FA50, FA35, DFA Macros & FA Ltd lenses are like on film - just to have as a base for comparison. I think it might be a good idea to add those if possible to have as a comparison as I (and I am sure many others) will be curious to see how they fare wide-open at f/1.8, etc. (and stopped down) on 35mm.

Thanks again for your efforts - they confirm to me that the DA & DA Ltd's should only really be used for what they were intended for - APS-C.

Cheers,

[Alan 2]

I think we need it clarified which glass is FF. It is true that it is quite some work to do. But finally we can avoid investing into the wrong direction. And I hope Pentax will not release non-FF glass where it has no benefit.

Please rate this thread if you like it. So maybe, Adam makes it sticky

I also updated my initial posting to contain a summary table of the results obtained so far. Thanks for watching.

This is just one more reason why Pentax will not come out with a FF camera in the forceable future. If you really are that obsessed with FF why don't you join the Canikon crowd. No hard feelings here.

[benjikan]

This is just one more reason why Pentax will not come out with a FF camera in the forceable future. If you really are that obsessed with FF why don't you join the Canikon crowd. No hard feelings here.

Whoa....Not nice at all! These guys put a lot of time and effort in to these tests. Now tonight before you go to bed take an empty glass and put it upside down next to you. In the morning turn it right side up and fill it up with water. This will give you a greater understanding of the Zen approach to how to start off each new day.

I commend the efforts of all of the contributers to this post for taking their time to test these lenses.

Thanks
Ben

[Alan 2]

Whoa....Not nice at all! These guys put a lot of time and effort in to these tests. Now tonight before you go to bed take an empty glass and put it upside down next to you. In the morning turn it right side up and fill it up with water. This will give you a greater understanding of the Zen approach to how to start off each new day.

I commend the efforts of all of the contributers to this post for taking their time to test these lenses.

Thanks
Ben

Okay, shoot the messenger. It's obvious the DA lenses will not work well on FF digital. That's not surprising as they're not designed to do so. What's negative is when the FF pushers tell people not to buy lenses that won't work for FF, and for Pentax not to design any more. Doesn't leave a lot of choices. If you really need or want FF digital you have the wrong camera system. There's nothing that Pentax is doing to indicate that they plan on going FF in the near future. The two most recent lenses, the DA35 macro and DA17x70 will not work well on FF.

Nothing wrong or negative with changing systems. I switched from Canon to Pentax in May, and I did it because for what I do I don't need or want FF, and I love primes. I've been very happy with the two DA limited primes I have, and more coming in the near future. I came to Pentax because they have what I wanted. If you really need FF digital then go do it. You have several choices out there. Coming here and telling people not to buy some of best lenses around because they won't work well on FF, now that's foolish.