Originally posted by arnold
An interesting fact about the LX Auto feature: Since the auto exposure circuitry works off the light reflected off the film (or pressure plate), it won't work with the back door open. Something else I noticed that may be related to this, is that it takes time for the auto feature to function after the lens cap is removed. It is as if a charge (capacitor?) needs to build up from light coming through the lens, and reflecting off the pressure plate, before the circuitry can function. After that it is perfect in its long exposures. Having the cap off for a brief time in light, seems to do this if the camera has been sitting in the dark for some time. Once the "charge" is there, the timer works as it should, otherwise it just fires instantly. Mind you, the pressure plate has a different reflection value to film one needs to consider.
I would be interested to hear what your LX does in the dark if it has had the cap on for a few days.
A quick edit to #52 post. The shutter auto timing problem was cured by rotating both the ASA dial and the speed selector several times to clear oxidation from the contacts. The only other problem I encountered was after using mirror lock-up. Mirror lock_up worked fine initially then, after de-selecting lock-up and firing the shutter, the mirror stayed up. It could be released by using (opening) the shutter advance, but the problem of mirror locking up after each shot, persisted. I then switched the control lever over to Timer and eventually whatever was in this complicated mechanism reset. The depth of field operation has no issues regardless and is safe to use. After trying a couple more "lock-ups of the mirror" and the problem persisting, I decided never to use this feature again; the mechanism seems rather frail. The rugged Spotmatic and K series plus MX seem to me to be the most trustworthy film Pentax's