K-3. Any ASA?
Posted 17 July 2007 - 09:00 PM
Posted 17 July 2007 - 11:43 PM
Posted 18 July 2007 - 03:37 AM
I understand that there is a meter on the K-3 that goes up to 250, or something of the like. That's just for the light meter, correct? If you have a handheld meter, then the meter that adjusts the film speed doesn't mean anything, right?
Krasnogorsk 1, 2, 3 cameras have TTL light meter.
The scale of TTL light meter have scale of speed of shooting ( outside circle ), scale of speed of film at GOST ( inside circle ) and switch "on-off" inside.
A some versions of K-3 cameras, ( export version ) had scale of speed of film at ASA.
Yes, The original scale of speed of film at GOST ( russian standard of speed of film ) have digitals :
8, 11, 16, 22, 32, 45, 65, 90, 130, 250 GOST.
If you have film with speed at ASA you can use table :
25 ASA = 22 GOST
50 ASA = 45 GOST
100 ASA = 90 GOST
200 ASA = 180 GOST
The handle of light meter not influence on speed of shooting of camera, because, the speed of shooting of camera set by other handle.
We can see of eletrical circuit of light meter of Krasnogorsk cameras
This is simply circuit included light sensor - photoresistor, on-off switch, additional resistor, indicator, battery.
This is light meter system have not high sensitivity, big inertia and have peculiarity " the blindness".
What i mean " the blindness". If you open of aperture at F=1.9 , the big volume of light will go to sensor.
The sensor will have low resistance and circuit will have a high current.
You will change of aperture from F1.9 to 5.6...8..11, But, the sensor will on " the blindness" and you will need wait 20..30 second up to sensor begin of measuring of level of light correctly.
That's why, i recommend adjust of aperture from full closed (F 16) aperture up to correct position of indicator.
This is system of light meter have not high precision +/- 0.5...1 stops.
That's why, the modern, digital outside light meter give you better result of measuing.
The some sensors can lost sensitivity too much and you need test and adjust of light meter or modify of circuit for two batteries and re-adjust of additional resistor and mechanical control of light meter.
You can use of 1.5 v battery ( batteries ) type 625 with metal disk adapter.
Posted 18 July 2007 - 09:44 AM
Posted 18 July 2007 - 11:33 AM