Do I need to turn the safelight off during exposure?

68degrees said:
what do you guys mean by "meter" as in 'plugged into my meter'. You differentiate between meter and timer so I dont understand what you mean by metering. We did test strips in highschool to determine the expsoure. Is there a better way? some kind of metering device like for film?
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It's the same as in the camera. The meter (lightmeter) is one thing and the timer (shutter) is another.

For years, I used an old (antique by today's measure) Spot-o-matic meter that had been my dad's. It was an extinction type of device and worked better than any simple electronic B&W darkroom meter I ever encountered. It was used to first measure the shadows (for exposure) and then the highlight (for contrast) using separate density wedges. Once calibrated, it was more accurate than the usual first try using test strips. Given that a whole image test print is usually called for to see where dodging and burning is needed, it was generally accurate enought to eliminate the need for the initial test strips completely.
 
Dwig said:
It's the same as in the camera. The meter (lightmeter) is one thing and the timer (shutter) is another.

For years, I used an old (antique by today's measure) Spot-o-matic meter that had been my dad's. It was an extinction type of device and worked better than any simple electronic B&W darkroom meter I ever encountered. It was used to first measure the shadows (for exposure) and then the highlight (for contrast) using separate density wedges. Once calibrated, it was more accurate than the usual first try using test strips. Given that a whole image test print is usually called for to see where dodging and burning is needed, it was generally accurate enought to eliminate the need for the initial test strips completely.
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Intriguing! Is it anything like the Corfield Lumimeter? When did it come out? See http://www.rogerandfrances.com/subscription/lumimeter.html

Cheers,

R.
 
My safelight is always turned off when exposing the paper.

I find that I can concentrate better when burning or dodging, and also judge better when I need to do two exposures with different "filter" (I use color head, so it's not a real physical filter, just a combination of Yellow and Magenta light).
 
If processing B&W paper I would not worry too much about a safe light on/off.

I have developed in a canvas tent at historical events in the past. At one we were positioned close to a flood light for the event field. The tent was so light inside we did not need a safe light on at all to see what we were doing. Result with Ilford papers? Perfect, un-fogged prints. Much to my and my partners surprise.
 
Roger Hicks said:
Intriguing! Is it anything like the Corfield Lumimeter? When did it come out? See http://www.rogerandfrances.com/subscription/lumimeter.html

Cheers,

R.
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Similar.

Here's a link to a picture: http://www.etsy.com/listing/43118557/1952-photography-enlarging-meter-kinnard

The Spot-o-matic worked by taking two readings. First you did a shadow reading for exposure and then a second highlight reading to determine contrast.

It worked as a comparison meter. There is a white disc area on which the projected image fell. At its center was an illuminated spot ~2mm with three density wedges. First was the paper speed wedge set using the pointer near the power switch. The other two were operated using the tabs around the body of the meter. One was calibrated in times and the other in contrast grades.

You had to be careful to align the tip of the little spike with the illuminated spot while you were making the adjustments. My dad found, and I can confirm, that the illuminated readout scales were too bright to allow proper use. He made a masking cone which covered the readouts and had a small window located so that the line of sight through the window to the metering spot properly aligned with the spike also. We'd meter with the cone in place and remove it to read the results.

It had no provision for the differing paper speeds of different contrast papers or VC papers with varying filters. You would simply calibrate the meter for the speed of your normal paper (e.g. grade 2) and mentally adjust for the speed changes with other contrast papers/filters.
 
VC papers are far more sensitive to light than graded. Off during exposure is just a precaution.

You need to find the threshold exposure where the paper turns a slight grey. Then expose a sheet just below that and shield a portion. Expose to safelight illumination for 4 minutes. If the shielded portion shows after development and drying, the light is not safe. Dim it or move it further way.
 
I use the RH Designs Stopclock Pro enlarging timer and their Zonemaster enlarging meter. The timer has an outlet that powers the safelight, and switches the safelight off when the enlarger is on. This helps with focusing, and also lets me see the image more clearly for dodging and burning.
 
Ronald M said:
VC papers are far more sensitive to light than graded. Off during exposure is just a precaution.

You need to find the threshold exposure where the paper turns a slight grey. Then expose a sheet just below that and shield a portion. Expose to safelight illumination for 4 minutes. If the shielded portion shows after development and drying, the light is not safe. Dim it or move it further way.
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Im going to try this. Very concisely explained. Thank you.
 
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