yellow vs white easel

[wiggywag]

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!

 

[Sirius Glass]

No importance at all.

My easels are either yellow or black with a white background.

Steve

 

[Reinhold]

Back when single weight fiber papers were much more common, the theory was that an orange-yellow easel could act as a pseudo safelight for any light that was able to penetrate the paper and potentially fog the least dense (shadow) region of the print. Actually, the amount of light reflected back thru the paper is so weak that fogging of mid-tones and highlights is unlikely regardless of easel color.

A worst-case scenario might be a print on thin paper (single weight) having a large zone I black area crossed with small sharply defined zone VI+ areas. (Wire fence in sunlight, in front of coal-black shadows). The stronger light bouncing off of zone I could ...possibly... cause some edge flare into small, finely detailed zone VI+ areas.

Reinhold

www.classicBWphoto.com

 

[Steve Smith]

As the paper which is optically linked to the emulsion is white then the colour of the base can have no effect.


Steve.

 

[Jim Noel]

My easel is black so I don't even think of a problem.

 

[Reinhold]

Yep, like Jim all my home made easels are black. For focusing and composing I mark a grid on the back of a scrap print using a fine tip marking pen. Nice white surface for focusing, judging light levels, ...and the grid makes it a whole lot easier to get the image level and square.

If you haven't tried it yet, make a focusing sheet with a grid. Highly recommended.

Reinhold

www.classicBWphoto.com

 

[wiggywag]

Yep, like Jim all my home made easels are black. For focusing and composing I mark a grid on the back of a scrap print using a fine tip marking pen. Nice white surface for focusing, judging light levels, ...and the grid makes it a whole lot easier to get the image level and square.

If you haven't tried it yet, make a focusing sheet with a grid. Highly recommended.

Reinhold

www.classicBWphoto.com

Sounds interesting. Any suggestions for space between each line in the grid?

 

[Reinhold]

I just checked:

On an 8x10, I have 1" hi x 1.5" wide; on an 11x14, I have 1.25" hi x 1.75" wide.

It kind of depends on how thick the lines are... Too thick and too close together...it's visually distrcting.
Too thin and too far apart...it's hard to see the pattern and judge things.

Another reason for using a focusing sheet instead of focusing directly on the easel surface: if you use a precision grain magnifier you need a piece of paper of the same thickness as your printing paper under the magnifier. Otherwise your plane of focus will not coincide with the papers surface.

Reinhold

www.classicBWphoto.com

 

[RalphLambrecht]

...
Another reason for using a focusing sheet instead of focusing directly on the easel surface: if you use a precision grain magnifier you need a piece of paper of the same thickness as your printing paper under the magnifier. Otherwise your plane of focus will not coincide with the papers surface...

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. Having said that, if using black easels (which is a good idea), you need a white focusing sheet anyway.

 

[BetterSense]

As the paper which is optically linked to the emulsion is white then the colour of the base can have no effect.

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).

 

[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.

 

[RalphLambrecht]

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.

Grain focusers assume that whatever you focus on is directly underneath the focuser. Their focus plane is the bottom face of the focuser. In other words, if you focus on the easel and then expose on the paper, you'll make a small, irrelevant mistake. If you focus on a scrap piece of paper and expose on a paper of the same thickness, you don't make such a mistake, but you won't be able to see the difference.

 

[RalphLambrecht]

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.

Yellow will help, but I don't know how much, because I never used a yellow easel. It can't be better than black, but it should be better than white.

 

[wiggywag]

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.

and from what you say, I can loose some fine detail when I compensate

 

[RalphLambrecht]

and from what you say, I can loose some fine detail when I compensate

I'm not sure. It is like a double exposure, one is image-based, the other is fog, which hints at a loss of resolution, but I have not experienced a loss of detail, just ugly shadow traces from what I wrote on the back of the print.