Regula King KG help
I snagged a Regula King KG camera today. It has a built in extinction meter.
I have two questions of anyone who knows anything about this camera:
1) There are numbers at the base of the rewind knob, some letters too. What do they mean? Is it a way of setting the ISO of the camera or some sort of reminder of a setting or some such thing?
2) How the heck do I use the extinction meter? I have worked out that I'm to read off the least dim number I can see but I don't know how to translate that to either f-stop or shutter speed.
You cannot set an ISO (nor ASA) number on an extinction meter.
To use the extinction meter, you need the chart supplied by the maker. There is no standard for extinction meters so no interchangeable chart is possible. With my Braun Paxette, the chart is riveted to the ever-ready case: Attachment 68384 You could try this chart - for this chart, it assumes ASA 50 as that was the most common film at the time the camera was made. For other film speeds, you need to mentally adjust - for ASA 100, you close down one stop, for ASA 400 you close down three stops.
You also need to look through the meter for quite a long time to allow your eye to normalise - the instructions with my Paxette suggest 20 seconds! That said, the Braun extinction meter agrees quite closely with my modern digital camera.
You also would need to understand that ASA standard was altered in the mid 1950s so even with the chart a meter (of any type) made in the early 1950s is going to use the earlier ASA standard - a problem I have with my Zeiss Ikon Contaflex - and that would require a further mental adjustment.
I'm guessing the chart for my camera would have come on a card or something similar.
I do have ISO 50 film. I'd heard that the standard for ASA/ISO had changed but never did track down how big that change was.
I have an inexpensive light meter I could mount to the camera. I could load up with ISO 50 film and make my own cross reference sheet. It might take time to accomplish though. Perhaps time for some controlled light level experiments?
Thanks for your help.
I may be in luck.
I did some searching and found a small spreadsheet someone did for the extinction meter on the King Regula.
It was initially set up for ASA 40 film but black and white film speed ratings were doubled back in around 1960(??). I'll try it with ISO 100 film to see what happens.
There's a labeled ring around the rewind knob (at it's base). Could those be DIN numbers use to tell the photographer what film he/she is using.