[jfdavis58]

!

[Rolly]

Thanks for posting the info Ben,

I will keep my fingers crossed on a firmware fix rather than a chip fix.

In the meantime, I was out using this lens at f8 at the weekend and wow, it's sharp. I will certainly be keeping it.



Andy

To H**l with the lens problem... this is a gorgeous image!
Print it Big!

[mutley]

They offered to set up one of my bodies to work in conjunction with the lens, which I refused. I do not wish to take up one body exclusively for that lens. I am waiting on a firmware fix or a chip set change for the lens.

Ben

When you vocally refused, and mentioned the words "firmware fix", what was their exact reaction? They WILL solve it at all costs, and there are planned firmware updates?

Larry

[*isteve]

Just got the response from Pentax via their head office in Germany. They confirmed that there is a back focussing problem with the 21mm Limited exclusively. They offered to set up one of my bodies to work in conjunction with the lens, which I refused. I do not wish to take up one body exclusively for that lens. I am waiting on a firmware fix or a chip set change for the lens. I will use it in manual focus only. They are sending me back the two bodies and the two lenses i.e. the 21 and the 16-45 which didn't have a problem and focussed perfectly on the "0" calibration point. I will wait for the 16-50 f2.8 which I should have in ten days to use in lieu of the 21mm Limited. If it is anything like the Canon 17-40L lens which I used on 80 percent of my magazine work, I will probably do the same with it.

Ben

Would seem more to the point!!

I too am waiting for the 16-50 F2.8. If the Tokina is anything to go by its very sharp and has little distortion - just hope they reduce the flare issue.
I am also lusting for the 50-135. With these two, just about any studio work is possible - not to mention everything else.
Some zooms are IMO good enough to compete with primes especially stopped down a bit.

[RiceHigh]

When you vocally refused, and mentioned the words "firmware fix", what was their exact reaction? They WILL solve it at all costs, and there are planned firmware updates?

Larry

I always wonder why people are hoping firmware (software actually) could resolve some possibly hardware issue!(?)

[d.bradley]

I always wonder why people are hoping firmware (software actually) could resolve some possibly hardware issue!(?)

Software can compensate such issues. If the built-in firmware can adjust the FF/BF for the camera, why not query the lens serial number and adjust the FF/BF individually based on each individual lens? Store the adjustments in the ROM?

[benjikan]

Would seem more to the point!!

I too am waiting for the 16-50 F2.8. If the Tokina is anything to go by its very sharp and has little distortion - just hope they reduce the flare issue.
I am also lusting for the 50-135. With these two, just about any studio work is possible - not to mention everything else.
Some zooms are IMO good enough to compete with primes especially stopped down a bit.

Exactly my feeling..

[Richard Day]

Software can compensate such issues. If the built-in firmware can adjust the FF/BF for the camera, why not query the lens serial number and adjust the FF/BF individually based on each individual lens? Store the adjustments in the ROM?

I very much doubt if the serial number is recorded, but it could identify the lens model (Pentax lenses only) and make the neccessary (minor) adjustments. This is what the C***n 1D mkIII does.

IMO this would be a killer feature and elevate the K10D to true "pro" status, in the eyes of reviewers especially. I think this feature will be incorporated as standard in the near future in cameras aimed at the pro-am market.

[tcom]

I just reviewed my DA21 photos to check for any FF/BF problem.

f/8.0


f/8.0


f/6.7


Did I get a good copy, would the problem not be visible in these shots anyway, or should I have my eyes checked?

[davek]

Tcom, those look great to me. I too must need my eyes checked.

If the problem is due to production variation, I can't see how they would fix it in firmware, unless they were to allow the user to calibrate the lens themselves.

[benjikan]

I just reviewed my DA21 photos to check for any FF/BF problem.

f/8.0


f/8.0


f/6.7


Did I get a good copy, would the problem not be visible in these shots anyway, or should I have my eyes checked?

Just send it to me, so I can make sure that your copy is really functioning well and don't worry if when I send it back to you that the serial number is not the same. That is just a formality...

[tcom]

lol, benjikan.

I have to add that these photos where taken on the K100D, did not test the lens extensively on the K10D so far.

[Alvin]

Just send it to me, so I can make sure that your copy is really functioning well and don't worry if when I send it back to you that the serial number is not the same. That is just a formality...

If you send it to me for testing, I may not send it back because I would need to do some extensive long-term testing.

[Wethphotography]

Just got the response from Pentax via their head office in Germany. They confirmed that there is a back focussing problem with the 21mm Limited exclusively. They offered to set up one of my bodies to work in conjunction with the lens, which I refused. I do not wish to take up one body exclusively for that lens. I am waiting on a firmware fix or a chip set change for the lens. I will use it in manual focus only. They are sending me back the two bodies and the two lenses i.e. the 21 and the 16-45 which didn't have a problem and focussed perfectly on the "0" calibration point. I will wait for the 16-50 f2.8 which I should have in ten days to use in lieu of the 21mm Limited. If it is anything like the Canon 17-40L lens which I used on 80 percent of my magazine work, I will probably do the same with it.

Ben

This is a fascinating thread. But I am still a little confused. Is the back focussing problem exclusive to the 21mm on the K10d or on any pentax dslr? Thanks for continuing to share your experiences.

[RiceHigh]

This is a fascinating thread. But I am still a little confused. Is the back focussing problem exclusive to the 21mm on the K10d or on any pentax dslr? Thanks for continuing to share your experiences.

Both, I think. See:-

RiceHigh's Pentax Blog: AF Accuracy's Dependency on Lenses and Yellow Light

RiceHigh's Pentax Blog: Focus Calibrations for (Pentax) (D)SLR Bodies and Lenses