Can the spotmatic F meter with all M42 screw mount lenses?

The subject contains my question. But I'll the throw in another. Has it ever been settled what batteries work with spotmatics?

<p>Mine is fine with a 625a.</p>

The spotmatic f will allow open

aperture metering with the super

multi coated takumars. It will

use stop down metering with all

other lenses.

The spotmatics have a voltage

circuit that allows it to meter

properly with 1.3 and 1.5 v

batteries.

<p>Wonder why Pentax Spotmatics initially went with a rather obscure battery, the PX-400 / RM-400-R instead of the common S-76 or PX-625?<br>

Spotmatic F fortunately used the more common 625. Can't think of any other camera makes that used that small 400 battery. What's a good substitute short of using hearing aid / zink batteries?</p>

<p>On my SP I used an alkaline LR66 (watch battery) with a little O-ring to center it. Those batteries often appear very cheaply at Big Lots and similar stores. It seems to work fine. Remember, though, that on most such batteries, the + side is the outer shell, so that outer shell goes up into the case. In middle speeds the meter may appear to work when the polarity is backwards, but it will not pass the battery test (put ASA to 100, shutter to B, and needle should drop to the bottom).</p>

<p>according to the manuals on the excellent butkuis site<br>

come m42 cameras metered at exposuire time and full aperture<br>

with mose <br />ordinary" m42 lenses.</p>

<p>I am not surre but some early m42 lenses may not accurately<br>

linew upso the focus line is noiy at the top.<br>

not sure<br>

s</p>

<p>I just put my first roll of Provia through a Spotmatic F with a 50mm SMC Takumar 1.4. It will be out to NCPS shortly. I'll report back when results arrive.</p>

<p>Mine has a functioning 625 battery in it from the collector who kept all his 500 or so bodies up to speed. I bought 7 bodies and a bunch of lenses when the widow cleared the inventory through our camera club. The Spotmatic F sure feels good.</p>

<p>I really like the Spotmatic F. Several years ago I purchased one on eBay that was like new cosmetically and mechanically, but the meter didn't work. I sent it to Camera Repair Center in Fort Worth and he was able to get the part to make it work as evidently it took the same parts for the meter as the later K1000. I just wish the meter had an on-off button or switch so it could be disabled when not needed.</p>

<p>It metered in open-aperture with all Super Multi-Coated Takumars and in stop-down mode with the earlier Takumar lenses. I'm assuming it would work the same with other non-Pentax M42 mount lenses, but I didn't own any to know for sure.</p>