http://www.sigma-imaging-uk.com/support/tele-converters_comp.htm

Regards,

John

I'd agree with those statements, but not if your viewfinder/focusing screen is giving you a very dim image which is the point I'm making, I don't know of anyone in theire right minds who wants a really dim viewfinder

John

I came to the same conclusion after having a K-7 on loan to me for a week or so, kept the K20D, waiting for the next one to come along. I prefer the ergonomics of the K20D, the 5.2 fps on the K-7 was a very good feature though

Regards,

John

With a really dim screen you'll find it virtually imossible to judge sharp focus, especially with a fast lens @ f/1.4 because the DoF is very shallow. Back in the day when I used a Pentax MX I always had a matte screen fitted:

http://www.bdimitrov.de/kmp/misc/focus/screens/circle.gif

or grid screen to help composition:

http://www.bdimitrov.de/kmp/misc/focus/screens/circle_grid.gif

I never really liked focusing aids like split prism etc. I use the original screen in the K20D for manual focus without issues. I think the K-7 screen would be every bit as good if not better, being as it's 100% view 0.92x. The perceived difference in DoF you're seeing through the viewfinder is probably due to the magnification offered by the viewfinder and screen but has no effect on actual DoF. Pentax make some of the best viefinders of any affordable DSLR's IMHO, try looking through a Nikon D3000

Regards,

John

I've never had the opportunity to use one but there's a review here:

http://www.photozone.de/canon-eos/323-sigma-af-55-200mm-f4-56-dc-lab-test-report...

and the Pentax DA 50-200 here:

http://www.photozone.de/pentax/138-pentax-smc-da-50-200mm-f4-56-ed-review--test-...

I sold the DA 50-200 I had and bought a Tamron 70-300 LD Di and found it much better.

Regards,

John

Hi Archie,

thanks for the comment, it's roughly the same size as the Sigma as far as I can tell, but the Sigma lacks the bulbous front element and can be used with filters. I'm looking forward to using the Fiseye sometime in the not too distant future

Best regards,

John

Hi Archie,

Thanks for your comments. I couldn't really justify the Pentax 10-17 price wise, although it's undoubtebly a fine somewhat unique lens. The Samyang really appeals to me, the DA15 and FA31 are on my wishlist, I'd love to own both these very fine lenses. The problem is I have the Sigma 10-20, Pentax FA28/2.8 and FA35/2 so I've basicly got that range covered and can't really justify the purchase of DA15 & FA31
I too have been selling off some of my older lenses as I purchase new but seem to have got to the point where I'm reluctant to let any more go, the replacement for the K-7 may change all that, until then I continue to use the K20D which I really enjoy.

Best regards,

John

Welcome to the meeting

John

I wouldn't recommend using a TC with a wide to standard zoom, unless you intend to use it only at the 50mm setting.

Regards,

John

That's a good choice, I really like the DA15, but it's a little expensive right now, I don't use Fisheye lenses that often but I've been missing having one for the APS-C format, I think £212 is a reasonable price for a lens that will be used infrequently.

Best regards,

John