On Sep 13, 2010, at 7:47 PM, Steven Desjardins wrote: > Huh. Harder question than I thought. BTW, the lens in question is an > bargain M 200 f4 that I got (well, in two days) for $70 from KEH. > I'll post some results.
I had an M200/4. I found it quite good and used it frequently at one time. Paul > > On Mon, Sep 13, 2010 at 4:51 PM, P N Stenquist <[email protected]> > wrote: >> >> On Sep 13, 2010, at 3:02 PM, John Francis wrote: >> >>> >>> I believe the issues surfaced when using lenses with a large maximum >>> aperture (such as a 50mm/f1.4). >>> >>> Although Pentax never explained exactly what was happening, the most >>> plausible hypothesis I saw was that the exposure metering in the K10D >>> (and, I would assume, in later cameras) had some sort of compensation >>> curve for the metering system based on the maximum aperture of the lens >>> (presumably because of known problems with light hitting sensors at an >>> oblique angle). An 'M' lens does not communicate maximum aperture (or >>> the aperture to be used) to the body, so the exposure correction would >>> not be performed (or would be performed using one fixed value for all >>> 'M' lenses at any aperture). >>> >>> I didn't pay too much attention to the issue, because I decided to go >>> with 'A' or later lenses back in '95 when I got my PZ-1p, so I rarely >>> put an 'M' lens on any of my later bodies. And, in any case, I don't >>> assume the metering on any DSLR is going to give me as good control of >>> the exposure as I can get by looking at the histogram. >>> >>> The "green button" metering technique should get you close; just be >>> prepared to apply some exposure compensation if you want it spot-on. >>> That was necessary (at least with the *ist-D and K10D) anyway; from >>> what Paul Stenquist says the K-7 may do rather better in this regard. >>> >> >> I've shot a bit with a K 85/1.8 on the K7, but haven't used it extensively >> and don't recall how successful those attempts were. I'll have to give it a >> try and see how it does wide open and at a small ap. >> Paul >> >>> >>> On Mon, Sep 13, 2010 at 08:35:49PM +0200, Jens wrote: >>>> >>>> I may be using my M lenses too little. But I have never noticed any >>>> exposure problems - except for those caused by the well known "slow >>>> aperture >>>> syndrom", occuring when lenses are left unused for too long - or stored >>>> with >>>> open aperture blades (on a camera or otherwise). >>>> >>>> I use a Seikanon wide angle macro lens quite often - which works like an >>>> M lens. It's an absolutely brilliant lens - which I believe is made by a >>>> company related to the later so well known Seiko brand. No exposure >>>> problems, that I know of. Razor sharp. >>>> >>>> Regards >>>> Jens >>>> -- >>>> Treat others as you would like to be treated yourself. >>>> >>>> On Sep 13, 2010 19:02 "Steven Desjardins" <[email protected]> wrote: >>>>> >>>>> I've never really used an M lens on a Pentax digital, but I'm thinking >>>>> about buying one. I know the green button trick, but how well does it >>>>> actually work? Metering OK and all that? >>>>> >>>>> -- >>>>> Steve Desjardins >>>>> >>>>> -- >>>>> 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. >>> >>> -- >>> 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. >> > > > > -- > Steve Desjardins > > -- > 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.
