Canonet G-III QL17 625A battery

I just got my hands on a Canonet G-III QL17 and am having some battery issues. I've tried both an Wein cell and a 675 in the MR9 adapter and neither seems to power the camera. However, a 625A (1.5v alkaline) works just fine. So, I'm off for a day of shooting Kodak Gold 200 tomorrow and need to know what ASA to set. With my F-1, I'd set it at ASA 80 - the same for the Canonet?

Good morning, Tony;

Yes, cutting the ISO or ASA film speed rating in half and setting that on the dial will usually get you into the proper range for using a 625 alkaline cell in place of the old mercury cell.

The point about the CRISCam MR-9 adapter not working is a puzzle. Mine have been working fine with a Silver-Oxide battery in them. Do you have a volt meter you can use to measure what the camera is seeing for voltage on the contacts? It is possible that there is a problem with either the diode or with a soldered connection in the MR-9.

If you want to go through it, send a PM to me and we can discuss the way to test the MR-9 and check to see that the diode was installed correctly. If the diode is in backwards (actually a fairly easy mistake to make if you are just a little careless), the reverse voltage blocking charactersitic of the diode will not allow the device to supply power from the battery with the expected slight voltage drop.

Hi Ralph,

The MR9 works fine in my Canon F-1, just not the QL17. I'll have another go at it, though. I'm off to shoot some pics right now.

Thanks,

Tony

Hi Tony,

This is real dumb, the only reason I mention it is because, well, I did it...

Are you putting the C.R.I.S. adapter in upside down? It'll fit that way.

Once I figured that out, I have enjoyed great service from it in my GIII.

Mike

Correct me if I'm wrong, but isn't a CRISCam MR-9 adapter designed for a silver-oxide battery? And isn't a 675 a zinc air hearing aid battery?

upnorthcyclist said:

Are you putting the C.R.I.S. adapter in upside down? It'll fit that way.

Click to expand...

Unfortunately, Mike, I have in the correct way and it's not working. Neither is the Wein cell that I have. Both of these work without trouble in my F-1 so it must be something else.

MattKing said:

Correct me if I'm wrong, but isn't a CRISCam MR-9 adapter designed for a silver-oxide battery? And isn't a 675 a zinc air hearing aid battery?

Click to expand...

The 675s that I have are silver oxide 1.5V.

Hi again, Tony,

One other little thing that got me with the GIII battery thing - one of the battery contacts, the little metal bump, has to be bright, shiny clean. No oxidation at all. It also can't be pushed down below the level of the surrounding insulator. Sometimes, with age, the springiness of the contact goes away and it it doesn't make a good connection. I've sort of scraped mine clean with a little dental pick. Also, crud gets around it, preventing it from popping up and making good contact with the battery or adapter. It doesn't take much.

Mike

MR9 Adaptor in QL17 GIII

I have exactly the same problem. I bought a Wein cell, didnt work. Now my MR9 adaptor arrived and got a new 386 (SR43W) and that doesn't work either.

I know I can shoot full manual, but this is frustrating as according my research with proper battery (which I have) the canonet's meter is very accurate.

I'm worried that it may be my light meter, but wasnt sure what happened as an end result of this thread.

The battery test won't necessarily work with Schokety diodes the meter should be ok and 1/3 stop throughout range.

The adapters have a diode...

An alkaline's error will be non linear bright to dark. Cept when it is near to 1.3v under load...


edit
The battery test will stress low current diodes for current not recommended...
The cameras can corrode the meter on/off switch which is not shielded from the elements, you ne3d to tqke the top off and slide a sliver into contacts cut from print paper dipped in electrical contact cleaner and then lube.
Removing the switch is easy getting it back more of a challenge...
Best not to ask how I know