Is it safe to use a red filter under the enlarging lens with Multigrade paper?

ferweb61 · Apr 17, 2018

I think something has been discussed about this point, but I have not found clear conclusions.
Though I have the appropriate (room) safelight from Ilford for MG paper, I have been using the red filter under the enlarger lens for short time to place paper etc.
I always thought there is no problem with this, and have not been aware of any effects in my prints, but I recently read about this and thought maybe I would get better results by not using it at all.
I will do some tests asap, but would be grateful if anyone can share some experience on this issue. I have not found anything about it in Ilford MGIV tech sheet, either.

I am also asking because I recently got a Focomat V35 VC, without the accessory red filter, and maybe I do not need it at all.

Regards

Fernando

tezzasmall · Apr 17, 2018

My enlarger doesn't have a swing in red filter, so I haven't used one for decades and have had no problems with my printing. I have used one in the past though, although it was a lonnnnnnnngggggg time ago.

If my memory is correct though, Ilford's below the lens filter kits contain a red filter in the set, but again I don't / haven't ever used it, but who knows it may come in handy one day???...

Terry S

glbeas · Apr 17, 2018

As long as the filter is not faded you should be good. The main worry would be any light reflected from the top of the filter that might scatter white light into the surrounding area. As long as that is in control there is no more problem than you would have from your safelight.

tedr1 · Apr 17, 2018

A lot depends on the length of time and brightness of the illumination, eventually some fogging might occur. I recommend those tests you mention because the actual red filter you have may be different from information that relates to generic red filters.

Ilford safelights for MG are amber, which indicates there is little sensitivity to yellow, from which we can argue there is even less sensitivity to red.

Ilford is good at answering technical questions, there is an email link at their website.

cowanw · Apr 17, 2018

I use a #25 to complete satisfaction on my Omega. It is better than the factory filter on the LPL.

msage · Apr 17, 2018

I guess I don't understand the question, are you using a filter below the lens when putting paper in the easel? Why not turn the light off when putting paper in the easel?

cowanw · Apr 17, 2018

The purpose might be framing the crop in the easel or preparing to dodge/burn.

Sirius Glass · Apr 17, 2018

I use red safe lights and red filters in the safe lights.

Michael W · Apr 17, 2018

I have seen paper get exposed when using under the lens red filters. That was when people were using them to position the paper and focus and had the lens set to the widest aperture. They should be OK if not used for long and the aperture at a small setting. I learned to print on enlargers that didn't have red filters and we used dummy paper to get the size and focus correct and then put the paper in to expose. It makes a difference whether or not you use an easel. I've seen where people don't use easels you pretty much have to use a red filter to position the paper. With an easel they are not necessary and I never use them, on the better safe than sorry principle.

ferweb61 · Apr 18, 2018

msage said:
I guess I don't understand the question, are you using a filter below the lens when putting paper in the easel? Why not turn the light off when putting paper in the easel?

Well, as others have said, the idea is to place the paper in the easel to check position and focus, but as Michael says, you can use dummy paper to get it correct and then expose with new paper.
I suppose I got used to checking the image under red light when I had enlargers with this filter fitted, and now I miss it, but it is not really essential.

Thanks a lot for your answers.

ferweb61 · Apr 18, 2018

tedr1 said:
A lot depends on the length of time and brightness of the illumination, eventually some fogging might occur. I recommend those tests you mention because the actual red filter you have may be different from information that relates to generic red filters.

Ilford safelights for MG are amber, which indicates there is little sensitivity to yellow, from which we can argue there is even less sensitivity to red.

Ilford is good at answering technical questions, there is an email link at their website.

Yes, thanks tedr1, it is a good idea to ask at the source too.

Ian Grant · Apr 18, 2018

tedr1 said:
A lot depends on the length of time and brightness of the illumination, eventually some fogging might occur. I recommend those tests you mention because the actual red filter you have may be different from information that relates to generic red filters.

Ilford safelights for MG are amber, which indicates there is little sensitivity to yellow, from which we can argue there is even less sensitivity to red.

Ilford is good at answering technical questions, there is an email link at their website.

You're right, a lot also depends on the time and intensity, whether the enlarger lens is stopped down etc. The problem is the Herschel effect where Red light causes image bleaching, with Multigrade papers the effect is small but can be enough to cause problems achieving the higher and lower contrasts. I've seen this first hand with red/orange safe-light filters in a small darkroom, it was cured by using the correct Multigrade Light Brown (Amber) 902/OC type filter.

Ian

Sirius Glass · Apr 18, 2018

ferweb61 said:
Well, as others have said, the idea is to place the paper in the easel to check position and focus, but as Michael says, you can use dummy paper to get it correct and then expose with new paper.
I suppose I got used to checking the image under red light when I had enlargers with this filter fitted, and now I miss it, but it is not really essential.

Thanks a lot for your answers.

I put a sheet of the same paper upside down in the easel to do the focusing with a grain enlarger and the enlarger bulb on bright white. Then set the enlarger light to the exposure level and set aside the "focus sheet". I then bring out the print paper.

cornflower2 · Apr 19, 2018

If you're reasonably quick and efficient with placing your paper (presumably for compositional purposes and as a last-moment check for position-in-easel before making the actual exposure) then you should be okay. It's easy to run a small test strip to see how long it takes before it fogs the paper, using your normal lens aperture, eg. f8. Remember that fresh, unexposed paper has a greater resistance to exposure than a piece that has already been exposed, so you should be wary of exposing the paper to red-filtered light AFTER you've given it the main print exposure. Andrew

RauschenOderKorn · Apr 19, 2018

Ilford supplies a red filter with the under the lens MG-FIlter kit. So it should be possible.

Gerald C Koch · Apr 19, 2018

Yes B&W paper is not sensitized to red light unless you are using a panchromattic paper. There may be one still made..

msage · Apr 19, 2018

ferweb61 said:
Well, as others have said, the idea is to place the paper in the easel to check position and focus, but as Michael says, you can use dummy paper to get it correct and then expose with new paper.
I suppose I got used to checking the image under red light when I had enlargers with this filter fitted, and now I miss it, but it is not really essential.

Thanks a lot for your answers.

OK, I thought that was the question.
I was taught not to use the red filter because of the chance of fog (see Ian's post). It seemed to a unnecessary step with no advantage and a few potential problems.
It is great if any technique works for you no matter what anyone says!

CMoore · Apr 23, 2018

Sirius Glass said:
I put a sheet of the same paper upside down in the easel to do the focusing with a grain enlarger and the enlarger bulb on bright white. Then set the enlarger light to the exposure level and set aside the "focus sheet". I then bring out the print paper.

Yeah.....i still must be missing the idea of the OP.
I could supply Composition/Focus Sheets to 20 photographers.
What can you do, in the darkroom, with a "good" piece of paper, that you cannot do with a "bad" sheet that is inserted in the easel, upside down.?

Sirius Glass · Apr 23, 2018

CMoore said:
Yeah.....i still must be missing the idea of the OP.
I could supply Composition/Focus Sheets to 20 photographers.
What can you do, in the darkroom, with a "good" piece of paper, that you cannot do with a "bad" sheet that is inserted in the easel, upside down.?

A good sheet of paper is the same type of photographic paper that you are using. Therefore a bad piece of paper is a paper of different thickness.

MattKing · Apr 23, 2018

Sirius Glass said:
A good sheet of paper is the same type of photographic paper that you are using. Therefore a bad piece of paper is a paper of different thickness.

And of course, there are a myriad number of sources attesting to the fact that due to depth of focus, the thickness of the paper doesn't matter, and that when it comes to using a grain based focus finder, there is no benefit to using a piece of paper at all.
That being said, I gain a feeling of comfort when I use one. Most likely because it is easier to tell if the image looks focused.

paul ron · Apr 24, 2018

ive never had any problems. just do a test strip to be sure?

no big deal!

Sirius Glass · Apr 24, 2018

paul ron said:
ive never had any problems. just do a test strip to be sure?

no big deal!

Sometimes.

CMoore · Apr 24, 2018

Sirius Glass said:
A good sheet of paper is the same type of photographic paper that you are using. Therefore a bad piece of paper is a paper of different thickness.

You don't say.....what are some types that you are using.?
I will send you, for free, a whole bunch of Good Pieces therefor.

Is it safe to use a red filter under the enlarging lens with Multigrade paper?

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