Minox 35gt is underexposing?

[Sparrow]

My new to me Minox seems to be consistently underexposing.

I ran a test film, the same scene at each of the camera's asa settings ... and it looks to me to be 2 to 2.5 stops off, sorry about the photo, a tube has gone on my light box so I had to use the monitor



the film was fuji 400 superia

this is the same thing inverted desaturated, the little red No's are the grey% of that grey card as CS sees it



Two questions, first, do you think 2 stops?

and secondly, anybody know how to adjust it?

I may just print another sticker for the asa dial that goes from 100 to 3200 asa

 

[btgc]

Seems that little Yashica I recently got also underexposes. About THREE stops. As I don't use slow films in RF's this effectively extends ISO range from upper ISO800 to 6400, still allowing to use ISO200 film rated as ISO50. Cool 🙂

I'm not sure about reasons. Maybe those old CdS cells just age?

 

[Chriscrawfordphoto]

Those cameras were made for mercury batteries. Using modern 1.5 volt cells causes about 2 stops of underexposure with most CdS cell meters made for mercury batts. Use Wein Cells or the MR9 adapter, or get it adjusted for silver-oxide batteries.

 

[Sparrow]

Hi Chris, I have an adaptor with a diode in to give a constant 5.6v from 4 silver oxide cells, so I don't think it's that

 

[Chriscrawfordphoto]

Hi Chris, I have an adaptor with a diode in to give a constant 5.6v from 4 silver oxide cells, so I don't think it's that

Ahh, damn. Probably a bad CdS cell. The cells are less than a dollar each at radio shack. The trick is that those might not fit the camera size-wise and you'll have to have it recalibrated as each cell reads different so the camera needs setup for accuracy on the new one.

 

[btgc]

Those cameras were made for mercury batteries.

I also can confirm my camera still has mercury cells, giving almost 1.35V each.

 

[Finder]

Can't you just compensate with the ASA dial?

 

[btgc]

Can't you just compensate with the ASA dial?

sure, I can. I just have to re-check exposure - initially I got impression that in daylight it's spot on, and underexposes in dim light. If it constantly misses 3 stops, it's easy then. If underexposure varies depending on light conditions, then I'm better off using something more stable.

 

[Sparrow]

Can't you just compensate with the ASA dial?

I'm not sure, I have a 400 in at the mo with the camera set at 100 to check.

But I'd like to adjust it if I could