In camera meter and app meters are different

Hey all,

I have a Pentax Spotmatic SP. Got it off eBay a while ago and have been shooting fine, no problems, however I recently put a battery (LR41 1.5V) in it for the light meter and I’m not quite sure if its working properly.

A roll of Kodak400 is currently in the camera. I tested it against three light meter apps (i don’t own an external light meter), with aperture 2.8 on everything, and all the apps said a shutter speed of 1/20-1/30, whereas my camera said 1/250. Huge discrepancy.

i think i’ll finish this roll using the internal light meter and see what happens, then get it CLA’d if need be, but i just wanted to bring this here and see what others may have to say.

yall think my camera light meter is off, or the apps? spotmatic owners - have you found your internal light meter to be much different from others?