have you seen this?
" DA Lenses on Full Frame
Pentax DA lenses (and their DA L kit counterparts) are designed for crop bodies, but some cover the full frame image circle better than others. We plan to test every Pentax DA lens on the K-1 and publish our findings in an in-depth review. Until then, refer to the DA lens full frame test compilation maintained by the community.
As a rule of thumb, you can expect ultra-wide DA lenses such as the DA 14mm or DA 15mm to require crop mode. The same would go for kit lenses like the DA 18-55mm. Primes and zooms covering "standard" focal lens ranges are generally going to be less problematic. For zooms coverage will almost always vary based on the selected focal length. Refer to the thread above for information on specific lenses, and stay tuned for our upcoming tests for details. "
Read more at:
Pentax K-1 Lens Compatibility Guide - Articles and Tips | PentaxForums.com
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DA lenses on Full Frame: Test Shots thread
Posted By: falconeye, 07-07-08, 16:50 (Offline)
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.
Read more at:
DA lenses on Full Frame: Test Shots thread - Page 34 - PentaxForums.com