Jostein, I just checked on the K20 with the 77 Ltd @ F8. Results were the same as with the K-7 and 540. No anomaly when the 540 was zoomed to 48mm. Regards, Bob S.
On Tue, Jul 21, 2009 at 12:55 PM, AlunFoto<[email protected]> wrote: > Thanks Bob! > That's the final nail in the coffin I guess. > I dread the thought of sending it off, though. It will have to go to > Germany for repair, where Pentax Europe has dismantled its own > organisation and buy the service from a company that also serve other > manufacturers. Rumors of extremely long response times are > reverberating both in virtual and physical spheres. :-( > > Jostein > > 2009/7/21 Bob Sullivan <[email protected]>: >> Jostein, >> >> I just ran a series theu the K-7 and 77 Ltd at F8 with the 540 Flash. >> My flash doesn't show any anomalies when zoomed to 48mm vs 16, 24, 34, or 58. >> Exposure stays the same. I think you have a flash fault. >> Regards, Bob S. >> >> On Sun, Jul 12, 2009 at 4:03 AM, AlunFoto<[email protected]> wrote: >>> Could I bother you guys to take a look at this comparison: >>> http://www.alunfoto.no/temp/flashAnomaly/flashtest.html >>> >>> All shots obtained at a working distance of 2 meters, and with >>> constant ambient light. The 48mm series stands quite distinctly apart. >>> >>> Graydon and John (or others), if you still think this is rationally >>> explainable by other factors than a faulty flash, please let me know. >>> >>> Jostein >>> >>> 2009/7/11 Graydon <[email protected]>: >>>> On Fri, Jul 10, 2009 at 10:10:23PM +0200, AlunFoto scripsit: >>>>> You describe how I would expect the flash to function. My observation >>>>> was that at _one_ particular zoom setting, 48mm, the output is two >>>>> stops brighter than any other zoom setting. This also includes 58mm >>>>> which, as you say, should produce a more concentrated beam. If there >>>>> was any logic to this the 58mm zoom setting should have been even >>>>> worse than 48mm, but the histogram at 58mm is perfect... :-( >>>> >>>> If there's a step function in the output of the flash, though, and "over >>>> 48" gets stepped down and _up to_ 48 does not get stepped down, it's >>>> quite possible that 48 would result in blown highlights while 58 >>>> wouldn't. >>>> >>>> Why this is happening goes back to the usual "evil algorithm vs hardware >>>> fault" question. >>>> >>>> -- Graydon >>>> >>>> -- >>>> PDML Pentax-Discuss Mail List >>>> [email protected] >>>> http://pdml.net/mailman/listinfo/pdml_pdml.net >>>> to UNSUBSCRIBE from the PDML, please visit the link directly above and >>>> follow the directions. >>>> >>> >>> >>> >>> -- >>> http://www.alunfoto.no/galleri/ >>> http://alunfoto.blogspot.com >>> >>> -- >>> PDML Pentax-Discuss Mail List >>> [email protected] >>> http://pdml.net/mailman/listinfo/pdml_pdml.net >>> to UNSUBSCRIBE from the PDML, please visit the link directly above and >>> follow the directions. >>> >> >> -- >> PDML Pentax-Discuss Mail List >> [email protected] >> http://pdml.net/mailman/listinfo/pdml_pdml.net >> to UNSUBSCRIBE from the PDML, please visit the link directly above and >> follow the directions. >> > > > > -- > http://www.alunfoto.no/galleri/ > http://alunfoto.blogspot.com > > -- > PDML Pentax-Discuss Mail List > [email protected] > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and follow > the directions. > -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
