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.

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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

[Blue]

I just noticed the Tokina 10-17mm fisheye which shares the optical formula with the Pentax one, is rated for full frame bodies. The hoods look similar. I would guess that Pentax could tweak the DA for a FF body.


Tokina

http://www.tokinalens.com/products/tokina/sample/atx107-10-17mm.jpg

[falconeye]

I just noticed the Tokina 10-17mm fisheye which shares the optical formula with the Pentax one, is rated for full frame bodies. The hoods look similar. I would guess that Pentax could tweak the DA for a FF body.

This is fascinating information.

Just to educate myself: Is it correct that a fish-eye lens projects a 180° field onto the sensor plane (spherical projection)? If so, then the effort to fill a given sensor would be almost independent of sensor size. Except of course, that the projection size will be fixed for a given lens (i.e., APS-C and FF fish-eye would be same size and price, but different in their rear lens element).

Is this correct?

And why does one spedify a focal length? 180° is focal length 0mm

[Blue]

Falconeye, are you saying they may have a different rear element? Of course it is moot since Tokina no longer does the K-mount. It does imply the it is easily feasible for the DA to work on a full frame body though.

Edit: 4 of the 8 lenses in the AT-X Tokina line will work on full frame bodies. The 10-17mm, 50-135mm, 100mm macro, and the 80-400mm although the last one isn't a Pentax formula.

[falconeye]

4 of the 8 lenses in the AT-X Tokina line will work on full frame bodies. The 10-17mm, 50-135mm, 100mm macro, and the 80-400mm although the last one isn't a Pentax formula.

I am not sure that this holds true for the 50-135mm. Tokina writes: "lens gives digital photographers the similar to the industry standard 80-210 telephoto zoom lens in 35mm camera terms but is much more compact and lightweight." Sounds like the typical description of a crop lens.

[Blue]

I am not sure that this holds true for the 50-135mm. Tokina writes: "lens gives digital photographers the similar to the industry standard 80-210 telephoto zoom lens in 35mm camera terms but is much more compact and lightweight." Sounds like the typical description of a crop lens.

Canon also has the apc-h bodies that would help it out some as well. I'm guessing the people with the more basic apc-c canon bodies aren't likely to look at the Tokina lenses.

[architorture]

Hi all, I finally got my hands on a ZX-L recently, so I went ahead and ran a roll through to test some things - one of which was the coverage of the DA 12-24. I took pictures at each indicated focal length on the barrel and at f/4 and f/8or11 (I don't remember which). I did not remove my b+w wide angle slim clear filter - the effect looks like it would have been marginal anyway. I left the hood off. No tripod.

I have not made any even mediocre scans yet - all I have is the crummy noritsu minilab scans from the photo place. But I still thought it would be useful. In about 6weeks or so when I have some time I will make real scans.

Nevertheless, it looks like the lens gives full coverage from 18-24mm, however the corners are very blurry at 18mm & f/4.

click on the pictures to see them larger (as big as the crummy noritsu scan)

f/4

12


15


18



20


24



f/8(or 11?)

12


15


18


20


24

[falconeye]

I added an entry about the D FA Macro 100mm F2.8 WR in the opening post.

This is the first new lens released by Pentax being specified full frame officially by Pentax. Even the DA* 55mm f/1.4 was not specified as such by Pentax.

[Miserere]

Even the DA* 55mm f/1.4 was not specified as such by Pentax.

Falk, so is the DA* 55 full-frame compatible? It didn't seem clear from your first page on this thread. Maybe I don't know how to read...

.

[Deimo]

Hey Falconeye,
thx for the effort here.

I ve just bought the DA* 300 and the DA 12-24.
Now i am not sure whether i should keep them because in my opinion FF is near - new 100mm WR.
The 300mm seems to work fine FF but 12-24 is really not usable.

Do you have any new details comparing DA*300mm to F(A)* 300mm??

[falconeye]

Do you have any new details comparing DA*300mm to F(A)* 300mm??

Having the FA*300/4.5, I just need the time to run a roll of film to repeat my test

I got the impression that the DA* has a subtle advantage in center resolution over the FA*, so all in all, both lenses may be good choices for full frame. Not to forget the DA* 60-250 ...

[vespats]

Hi,
is the 60-250 confirmed as a FF lens? I have read both in different forums?

I am thinking about spending hell of a money for a new tele...

the DA* 300 looks really nice but the 60-250 would be more flexible.

Any test results?


the 60-250 is a FF lens:
Pentax 60-250 SDM Samples: Pentax SLR Talk Forum: Digital Photography Review

it is not:
Re: FA* 80-200 vs DA* 60-250: Pentax SLR Talk Forum: Digital Photography Review

[Adam]

DA lenses are not full-frame lenses, barring the 40mm, which is an exception due to its design being similar to that of the M 40mm pancake. A few other primes come close to covering the 36x24mm image area, but aren't quite there, I believe.

DA* lenses use a 1.3x crop factor rather than a 1.5x factor, so they would be usable earlier on at the wide range on a full-frame body than other DA lenses. But no, the 60-250mm is not a full-frame lens.

This is the first new lens released by Pentax being specified full frame officially by Pentax. Even the DA* 55mm f/1.4 was not specified as such by Pentax.

So were the previous DFA's. The entire DFA series is full-frame by definition (technically the new macro should be considered an FA J, since it doesn't have an aperture ring, but whatever- Pentax is just bending the rules a little bit).

DA lenses, by definition, are digital-only. While the 40mm gets the job done on full-frame, and possibly also the 55mm, Pentax won't officially admit it just so they can say "ooh look, this lens is designed exclusively for our DSLRs".

[vespats]

...OK let me correct my question.

How does the 60-250 behave on a film camera as a non FF-lens

Is there heavy vignetting? shadows? not at all?
At which aperture does it get better?

thx guys

[Adam]

...OK let me correct my question.

How does the 60-250 behave on a film camera as a non FF-lens

Is there heavy vignetting? shadows? not at all?
At which aperture does it get better?

thx guys

Just a guess, but at 60x1.3, so 78mm, you'd cover the entire image plane, and maybe around 85mm you wouldn't even have dark corners.

[falconeye]

DA lenses are not full-frame lenses, barring the 40mm, which is an exception ...

Adam, this entire thread is about a single topic: To go beyond this kind of oversimplifying statements.

In my original post (which I am keeping up to date), I classify new lenses (lenses released after the DA 16-45) according to their usefulness on FF bodies, using a classification scheme of -, o, +, ++, +++. +++ would mean that the performance is identical to a lens designed and optimized for full frame. E.g., the DA40 is classified as '+'.

The thread contains all discussion with respect to deriving the classification. It is based on test shots and numerical evaluation of test charts (or brick walls ). Questions and mere opinions or hearsay should not be posted. Knowing that a lens isn't black in the corners is not sufficient.

As soon as I find the time, I will add a rating for FA* 300/4.5 and DA* 60-250/4. (and fix the broken image links in my earlier posts -- the provider deleted my images said to stay forever -- he said the traffic was too high ...)

Again, I invite anybody to photograph a test chart on film, using a lens which doesn't have a rating yet, like the DA*55/1.4. And post the result here.

Please refrain from pure discussion without adding any new facts. Thanks everybody.


@vespats:
The DA* 60-250/4 has no visible vignetting (no black corners and no darkening) over the entire focal range (fully open). The same holds true for perceived viewfinder sharpness. Even with the hood at 60mm, the corners don't black out, a sign that Pentax may plan to reclassify this lens as 35mm. But this information is not sufficient to rate this lens. It may be anything between + and +++. I ask Adam the favour to delete his misleading guess (the previous post).

@architorture:
I have added your results to the opening post. Thank you very much for your effort. As soon as you have better scans, we can verify if my corner sharpness assessments were ok.