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Atracksler
7-Sep-2015, 13:27
I don't have an enlarger.

Id like to try out some DP paper.

I do have flashed, and strobes... Anyone prefacing with a strobe/speedlight set to 1/32 or 1/64? or any other solutions without an enlarger?

Thanks...

Jim Noel
7-Sep-2015, 13:49
Get a very small incandescent bulb, 5W or 7 1/2W. Mount it in a receptacle about 18-24 inches from the paper. Use either a switch to turn it on and off, or something opaque to block the light path. This was the method used by press photographers 70-80 years ago, and it still works.

Atracksler
7-Sep-2015, 13:51
how long should I pre flash?

SMBooth
7-Sep-2015, 16:32
Depends on the bulb , distance etc. Test, your looking for the first sign of change.

Michael E
7-Sep-2015, 17:13
Point your camera a white wall. Make sure it's out of focus, preferably with the camera set at infinity. Set the exposure according to previous test results (meter the white wall wall and subtract x stops). Expose the DPP in the camera.

Gary Beasley
7-Sep-2015, 18:44
I made a preflash for printing from a small desk lamp that I wired a dimmer to then hung on the wall over the work table. Hooked to a timer it made for some very easy to control preflashing.

Atracksler
9-Sep-2015, 10:22
So there isn't a hard and fast formula, probably a box to test and then I can get rolling.....??

Peter De Smidt
9-Sep-2015, 11:16
Out-of-focus white wall, a piece of white acrylic in front of the lens...all of those should work. As a starting place, try placing the exposure on Zone 0, i.e. meter it and close down 5 stops.

Jim Noel
9-Sep-2015, 11:29
how long should I pre flash?

Make test strips. Pick the time which just shows density above paper white.

Peter De Smidt
9-Sep-2015, 11:34
Jim gives good advice. You might also try pre-flashing for the amount just before the time that shows density above paper white.

Eric Woodbury
9-Sep-2015, 12:03
Jim, I pick the one that is just before a change in paper white.