Metering with Canonet QL17 GIII

[scorpius73]

I have noticed that my camera is off by a stop with the newer batteries. i think the old ones were 1.33 v and the newer ones are 1.3 v. so, if im using asa 400 film, i just set the asa on the camera to 200. have any of you done this? just curious if im the only one.😕 i also use my sekonic l-308s light meter when i have the time.

 

[sirius]

I haven't done what you suggest, but it makes sense. However, I know that modern batteries have a fall-off as they get older. The mercury (1.35v) and the modern replacement, the zinc air batteries, release a consistent charge for their lifetime.

Here is a thread that might help you . . .

http://www.rangefinderforum.com/forums/showthread.php?t=36353

 

[ruben]

I..... have any of you done this? just curious if im the only one.😕 i also use my sekonic l-308s light meter when i have the time.

I have two canonets, with the same battery type, bought at the same time.
Against my Sekonic 308 the one destinated for ISO 200 had to be adusted to ISO between 400 and 800. (stop and haf difference).

The other, destinated for ISO 1600, not supported by camera light meter, and therefore set at maximum camera ISO 800, reads as my Sekonic 308 set at ISO 1600.

Therefore both cameras contradict each other, due to uncalibrated light meters. Yet it was the great David Vestal who said the issue is not if your meter is uncalibrated, but wether it is consistent within its byas.

Cheers,
Ruben


PS
My comparizons are approximate, due to many variants, and to kitchinette style of testing.l

 

[ChrisPlatt]

The silver oxide PX625 cell has far more stable output than the alkaline version.
It's a little more expensive and harder to find, but well worth it...

Chris

 

[anirbax]

I found that with the same Canonet, there was about a 1/2 stop difference between the Mercury Cell 1.35v batteries and the newer 1.5v Silver-Oxide or Alkaline batteries. So I adjust the ASA setting accordingly.

Unfortunately, the difference seems to vary with ambient light levels, so it's dificult to get away with by tweaking the film speed setting.