yellow vs white easel

[RalphLambrecht]

How important is it to have a yellow easel compared to a white one, to avoid fog?

Which kind of papers are unsafe on a white easel?

Is it only when the light is very brigt, e.g. close to easel or full opening on the lense?

Thanks!

The color of the easel surface definitely makes a difference! You can test this yourself. Figure out what exposure you need to create a medium gray on your paper. Prior to making this exposure, mark the back of the print with a thick black felt-tip pen. Write a number on it or sign it. Then make the exposure and process normally. You should not be able to see your mark on the emulsion side after drying.

I did this test with double-weight Kodak, Ilford and Agfa paper and could clearly see the mark with white easels. They are now painted flat black and the problem is gone. I never had yellow easels, so I don't know how they are affected.

[RalphLambrecht]

I don't understand how you reach this conclusion. A white base would seem to ensure only that the colors reflected by the easel surface, whatever they may be, will reach the emulsion without being preferentially absorbed (due to the white base admitting all colors equally).

You are right! That is exactly what happens.

[Ektagraphic]

I use Ganz Speed Ez-el that is yellow and I have never had a problem. They are great.

[cowanw]

The color of the easel surface definitely makes a difference! You can test this yourself. Figure out what exposure you need to create a medium gray on your paper. Prior to making this exposure, mark the back of the print with a thick black felt-tip pen. Write a number on it or sign it. Then make the exposure and process normally. You should not be able to see your mark on the emulsion side after drying.

I did this test with double-weight Kodak, Ilford and Agfa paper and could clearly see the mark with white easels. They are now painted flat black and the problem is gone. I never had yellow easels, so I don't know how they are affected.

So if I have got this right, you can not see the actual black number through the print, as shown by your not seeing it when you have a black easel.

but when light is reflected back by the white easel, You can see the number.

So the number would be appearing whiter? since the reflected back light would make the print darker everywhere except the opaque number, where no light would pass through to fog the print.
Is that right ?
Regards
Bill

[phfitz]

Has anyone heard of 'paper negatives'? Yes, the light goes right thru the paper and will reflect off the easel. Kodak described making photo-copies with singl weight grade 5 paper back in the 1940's, place the paper face down and expose thru the back, produced a reversed negative photo-copy that could be read in a mirror or contact printed. You could try Ralph's experiment with a Sharpie on the back to see how this affects your set-up. Using a flat black easel removes the variable re-exposure of the print and should increase sharpness and fine detail.

[wiggywag]

The color of the easel surface definitely makes a difference! You can test this yourself. Figure out what exposure you need to create a medium gray on your paper. Prior to making this exposure, mark the back of the print with a thick black felt-tip pen. Write a number on it or sign it. Then make the exposure and process normally. You should not be able to see your mark on the emulsion side after drying.

I did this test with double-weight Kodak, Ilford and Agfa paper and could clearly see the mark with white easels. They are now painted flat black and the problem is gone. I never had yellow easels, so I don't know how they are affected.

So, your actually saying that my prints probably are a bit foggy today because of my white easels, and I can get better details and brilliance in the highlights if I paint my easels black?

If so I better paint them right away :-)

[Steve Smith]

No real need. There is plenty of DoF around your paper plane, several mm in fact. The thickness of the paper lifts the grain magnifier to the theoretical correct plane, but not having it creates a focusing mistake to small to make any difference.

In fact, Gene Nocon suggests not using a scrap piece of paper in his book on darkroom printing. And I personally think that grain magnifier manufacturers have already designed in a typical paper thickness. That's certainly what I would do if I was manufacturing them.


Steve.

[Steve Smith]

The color of the easel surface definitely makes a difference! You can test this yourself. Figure out what exposure you need to create a medium gray on your paper. Prior to making this exposure, mark the back of the print with a thick black felt-tip pen. Write a number on it or sign it. Then make the exposure and process normally. You should not be able to see your mark on the emulsion side after drying.

Whilst you can see the difference between reflected light using black and white easels, I suspect that the difference between yellow and white would be much smaller as a yellow surface will still reflect a fair amount of blue and green light.


Steve.

[RalphLambrecht]

So if I have got this right, you can not see the actual black number through the print, as shown by your not seeing it when you have a black easel.

but when light is reflected back by the white easel, You can see the number.

So the number would be appearing whiter? since the reflected back light would make the print darker everywhere except the opaque number, where no light would pass through to fog the print.
Is that right ?
Regards
Bill

Entirely correct! You can see the marking as a slightly lighter tell-tale sign in an otherwise medium gray print.

[RalphLambrecht]

So, your actually saying that my prints probably are a bit foggy today because of my white easels, and I can get better details and brilliance in the highlights if I paint my easels black?

If so I better paint them right away :-)

The effect of the white easel can be compensated with less exposure and more contrast, which is what you probably do instinctively anyway. The only risk, don't mark your prints on the back prior to exposure, as that may leave a tell-tale sign in the print emulsion.