"M" focus screen question

[surfotog]

I'm thinking of getting the "M" screen for my A900, but I'm unsure how well it works with slower lenses.
I'd like to use it for my Pentax M* 400/4 & 800/6.7 lenses on the A900.
I have no trouble focusing them on my 67II, but find shooting moving subjects nearly impossible on the A900. Static subjects are no problem.
They will be used in good light (Hawaiian sun), to shoot our large winter surf. Thanks for the help.

 

[Oren Grad]

I used the M screen when I had an A900. Because visual acuity varies, it's hard to say what will be best for you. But FWIW, I found that the M screen was consistenly dimmer than the standard screen but much easier to focus. The slowest lens and most unforgiving light I tried it with was a 35mm f/3.5 Super-Multi-Coated Takumar under relatively dim indoor available light. I'd say that was borderline for quick and positive focusing in hand-held use, but the stock screen would have been hopeless in the same situation.

I'd guess that under bright sun, the 400/4 would be no problem at all. I'm less certain of the 800/6.7, but of course the razor-thin zone of apparent focus will work in your favor.

Anyway, the screen isn't that expensive. I'd say it's well worth a try.

 

[edwardkaraa]

+1
I have been able to focus accurately with my stop down ZS 50 at 5.6 without problems. The long tele should be much easier.

 

[Bill_Green]

I used the M screen when I had an A900. Because visual acuity varies, it's hard to say what will be best for you. But FWIW, I found that the M screen was consistenly dimmer than the standard screen but much easier to focus. The slowest lens and most unforgiving light I tried it with was a 35mm f/3.5 Super-Multi-Coated Takumar under relatively dim indoor available light. I'd say that was borderline for quick and positive focusing in hand-held use, but the stock screen would have been hopeless in the same situation.

I'd guess that under bright sun, the 400/4 would be no problem at all. I'm less certain of the 800/6.7, but of course the razor-thin zone of apparent focus will work in your favor.

Anyway, the screen isn't that expensive. I'd say it's well worth a try.

+1 to all of that. I can focus reasonably comfortably to f8 in decent light.