Unexplicable exposure problem with paper negatives

[Larry Gebhardt]

Originally Posted by Jac@stafford.net View Post
Oh heavens, Tony. Pop for a brand new box of paper



Why, A 100 box of 8x10 is around UK£50.00 plus postage (say US$64.00). In the UK, £50 is a lot of money to squander unnecessarily. I'm not certain that $64 has the same 'value' in the US.

In addition, I've lots of boxes of paper so why not use them and what is wrong with trying to find answers that will enable me to use them efficiently.

regards
Tony

It’s not squandered if you still use the old paper. Get new known paper for your originals and save the other for use in the darkroom where you are not losing original shots. One of your other boxes you already own is where I would start. For paper negatives I’d choose rc glossy if you have some.

[tonyowen]

information for those interested from Ilford/Harman UK

Technical <technical@harmantechnology.com>

Hi Tony,

It's much easier to tell the emulsion side than by looking at the curl.

I would just look at the surface finish under glancing safelight.

The RC sheets are likely to be Glossy or Pearl, both easy to spot.

FB will likely be Glossy (If it's matt it's a little trickier)

Curl does depend somewhat on humidity and also how the product was manufactured, so can be variable, RC mostly lies pretty flat, sometimes the emulsion is on the convex side due to roll set, but this might not be reliable. The emulsion is normally on the concave side for FB.

regards

Tony

[jnantz]

Hi Tony

I hate to suggest you waste another sheet of paper but ...

Take a chunk of papers out of your box to see if they were all put in the same way ( you should be able to tell if they lie flat on eachother if some are upside down on the stack ) put all but 1 sheet back in the box and mark it with a pen the UP side. Close and put away the box and turn the room lights on or go outside and look at the paper to see which side is the emulsion. It won't turn black or grey right away but you will see it slightly turning and you will be able to see the sheen. Go back into the dark with the red light and look at the side that was the emulsion so you will have a better idea. Also, tape a piece of that paper oriented the same way the rest of the box is oriented. If you have a hacksaw, emery board or something to abrade an edge, rough a tiny bit of the whole stackand make your own "notch code" so you can tell just like with film.

Good luck making those paper negatives !
John

[tonyowen]

Good luck making those paper negatives !John

Hi John Thanks for response.

I’m slightly ahead of you.

I view the 8x10 sheet under a safe light in a darkened bedroom.
When I’ve identified ‘what seems to be the emulsion side’ I turn it over and mark the four corners. In addition, [because 4x5 film/paper is less than those dimensions - actually 99mmx124mm] I mark the central gap between the two 99mm wide strips. [I use a template to set the rotary cutter to the appropriate wide and length of the desired “4x5” pieces that will fit into a DDS].

After cutting and inserting the cut pieces into the DDS. The ‘off cuts’ are left in daylight. The emulsion side, as you say, discolours; so I know if the emulsion is on the unmarked or marked side of the 8x10 sheet. If it is on the marked side then I need to unload and reload the DDSs.
Since RC Pearl/Cooltone [according the Ilford/Harman] is not consistent in exhibiting a curl, then I do not know EXACTLY what I have. So I got back to Ilford/Harman regarding post processing attributes.

The answer was
“Pearl is a surface finish, Cooltone is a product type,. Different tones e.g. Cooltone / warmtone are very difficult to distinguish unless developed and under white light.
RC is very smooth and very flat also more flexible than FB
Normally FB will curl upwards and unevenly post processing,. So emulsion is on the concave side. RC doesn't tent to curl very much at all and should dry quite flat.”

My prints curl to the convex side, so I’m paper I’ve chosen is RC paper [Pearl or Cooltone].

Regards
Tony