Paper negatives

[tonyowen]

Pre-flashing?
Does anyone have any data from using a flash gun to pre-flash paper prior to exposure?
One of the flash guns I've got has a GN of 32 or 48 (dependant on hood setting) in metres at ISO 100.
The output power can be reduced to 1/16th power - Flash duration varies from 1/1000th s to 1/125,000th s
I realise there are a lots of if's, but's and maybe's - however I'd rather start with someone's proven data than just assume a random setting.
Also, there was an earlier mention of the paper's ISO rating after pre-flashing being increased by three stops.
All opinions and comments welcome
regards
Tony

[Ray Heath]

I assume you don't have an enlarger, is that correct?

Your flash will probably be too powerful and you will have to control output somehow. Then arrange some means of doing a test strip but you'll have to use the same distance from the paper each time etc.

It all just seems too hard. Why not use a small table lamp or a bulb hanging from the ceiling?

[Ray Heath]

Comments and observations please on attached - the only difference is 1m development time. Used PS to enhance including a sepia cast
regards
Tony
Attachment 150202

Looks like contrast is far too harsh. The nicely lit bridge in the distance has exposed nicely but the dark foreground is grossly over exposed. Forget trying to 'improve' results
by varying development, its not gonna help.

[donkittle]

Tony, I tried a flashgun at 1/128 power, held in the far corner of the room and the negatives turned black instantly when developed. I now use a keychain LED light held at the ceiling for 2 seconds when the negatives are on the floor - works great.

[tonyowen]

Tony, I tried a flashgun at 1/128 power, held in the far corner of the room and the negatives turned black instantly when developed. I now use a keychain LED light held at the ceiling for 2 seconds when the negatives are on the floor - works great.

Don
Thank you, that is the kind of information I needed
regards
Tony

[tonyowen]

Help please - how do I tell which is the emulsion side of multigrade paper.
I understood that the emulsion side was the concave side that forms naturally with a loose sheet of paper - ie the long ends lift off the surface.
HOWEVER, I'm 99.9999999999% certain that I'm cutting the 8x10 sheet concave up and putting the 4x5 cut pieces concave up in my dds.
BUT the images, when developed are the right way round!!!!
Also the images are slightly out of focus even though the gg image was needle sharp.
What am I doing wrong, or what do I not understand
regards
Tony

[Emil Schildt]

Help please - how do I tell which is the emulsion side of multigrade paper.
I understood that the emulsion side was the concave side that forms naturally with a loose sheet of paper - ie the long ends lift off the surface.
HOWEVER, I'm 99.9999999999% certain that I'm cutting the 8x10 sheet concave up and putting the 4x5 cut pieces concave up in my dds.
BUT the images, when developed are the right way round!!!!
Also the images are slightly out of focus even though the gg image was needle sharp.
What am I doing wrong, or what do I not understand
regards
Tony

if in doubt, wet your lips and then hold the paper between your lips for a couple of seconds - then open your mouth.... The emulsion side will stick to your lip...

[Andrew O'Neill]

If you are loading in a darkroom, you can see which side has the emulsion. If you are using glossy paper, it's the shiny side. If my grade niners can do it, so can you. If you can't tell, then try Emil's method. Personally, I wouldn't stick photo paper in my mouth, though. Lick your finger and touch the paper by the corner. Sticky side wins.

[Emil Schildt]

Personally, I wouldn't stick photo paper in my mouth, though. Lick your finger and touch the paper by the corner. Sticky side wins.

aah - it is all over anyway...

[Ray Heath]

Help please - how do I tell which is the emulsion side of multigrade paper.
I understood that the emulsion side was the concave side that forms naturally with a loose sheet of paper - ie the long ends lift off the surface.
HOWEVER, I'm 99.9999999999% certain that I'm cutting the 8x10 sheet concave up and putting the 4x5 cut pieces concave up in my dds.
BUT the images, when developed are the right way round!!!!
Also the images are slightly out of focus even though the gg image was needle sharp.
What am I doing wrong, or what do I not understand
regards
Tony

Hey Tony, I'd say you are totally wrong. FB curves to the emulsion side, RC curves to the non-emulsion side.

Don't sweat it, do a test, mark one side of a sheet of paper corner to corner, cut, load one DDS mark up, one mark done, expose, process, evaluate.

Don't over think it and KISS.