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Matus Kalisky
24-Jan-2007, 03:28
Hi,

I finally decided to try the dark side of the photography and my first attempt is going to be the contact printing, though I have some questions here.

Firstly, let me mention what and how I want to do:
I have some 4x5 BW neqs (ilford fp4+ up to now, next TMax 400), want to print them on Ilford fiber paper, I will be using standard Ilford chemicals according the papar data sheets. My lightsource will be some small bulb. I will be using paterson printing frame for the convenience. Ok. So far so good.

Questions:

1) How will the type of the light source influence the contrast I will be getting? (thungsten, halogen, ...) - which one to choose?, how strong to get reasonable printing times (not too short)?

2) Would it be possible to use the filters (ilford) to adjust the contrast of the print
with some of the lightsources mentioned?

3) How to dry the fiber print to get it flat? I've found some info that one should use some kind of "blotting paper" (I am not sure about the translation) - where to buy it? Should I rather buy some old electric dryer? Or just hang the prints and let them dry (wil take longer I guess)

4) With aforesaid setup - what would be your advices for improvement or changes ?

thanks a lot

Matus

Patrik Roseen
24-Jan-2007, 05:26
From your questions I gather that you are really interested in using variable contrast paper (multigrade).

The multigrade paper consists of different emulsions reacting to the blue spectrum of light and to green spectrum of light. Different contrast is achieved by filtering different proportions of green and blue light, using multigrade filters.
http://www.ilfordphoto.com/Webfiles/2006130201152306.pdf

1) for variable contrast you need a light source producing the 'right' light for the filters to work. Look for photographic light bulbs etc. The light should not be too strong. I use the light from an enlarger where the light can be controlled by changing the aperture of the enlarger lens.

2) Yes, variable filters can be used, but you need to make sure that any unfiltered light does not reach the contact print.

3) I use an electric dryer where the paper is held flat between a metal plate and a stretching cloth,(I do not know the english word for it). My experience is that the paper should dry slowly. I always dry the paper with the emulsion towards the cloth.
I then place it under pressure for even better results.

I have never achieved a flat fiber paper by letting it dry on its own, laying flat nor hanging. Some kind of pressure seems necessary...

4) ...

Good luck!

j.e.simmons
24-Jan-2007, 05:32
I don't believe your choice of light source will affect contact prints. By putting the negative in contact with the paper, you are eliminating the effects the light source causes in enlarged prints.

As for how strong, it's a matter of the wattage of the bulb and the distance of the bulb from the negative - in combination with the density of your negative. In other words, you'll have to make a few tests. In general, a regular 60 watt bulb (or something in that range) about a half meter above the paper, with a negative developed to enlarge, should give you a reasonable printing time.

If the filters are large enough to cover the negative, you should be able to use them to adjust contrast. They are made for tungsten bulbs.

I dry my prints by putting them face down on fiberglas window screen. I don't think the blotting paper is necessary. The prints will air dry, and if they are not flat enough for you, you can heat them with a press or even an iron for clothes, then put them under a weight (several large books) for a few hours.

It looks as though you are on your way.
juan

Jan_6568
24-Jan-2007, 17:09
Hi,



1) How will the type of the light source influence the contrast I will be getting? (thungsten, halogen, ...) - which one to choose?, how strong to get reasonable printing times (not too short)?

For bromide paper I use ordinary 20W frosted bulb hanging about one meter above my table. It gives reasonable exposure times (10-20 sec usually). If you find this light source too strong you can reflect the light from the wall or so


2) Would it be possible to use the filters (ilford) to adjust the contrast of the print
with some of the lightsources mentioned?


I think you would need a sort of box to put the bulb inside and a drower for filters. I can imagine such box could be easily built from a cardboard box.


3) How to dry the fiber print to get it flat? I've found some info that one should use some kind of "blotting paper" (I am not sure about the translation) - where to buy it? Should I rather buy some old electric dryer? Or just hang the prints and let them dry (wil take longer I guess)

I tape my prints to the glass plates, facing emulsion to the air, using water activated adhesive tape - such tape as it was used for sealing packages 20-50 years ago :). After prints are dry (here in Arizona it takes 3-4 hours) I just cut the tape with sharp knife. It works very nice. If you decide to take this method you should leave about 2 cm wide margins for taping, also it works better if you place glass plates horizontally, this way you avoid possiblity of gettig some glue on your prints. If you have to use vertical glass plates (as I do) take care not to use too much water.


4) With aforesaid setup - what would be your advices for improvement or changes ?


I guess for contact printig this is all you need except darkroom timer or metronome.

good luck

Jan

Matus Kalisky
26-Jan-2007, 03:59
Thanks for all your answers. But I have some more questions:

- Is it possible to buy some kind of test negativ with steps in density with which one can make at one shot the testing print - to get the exposure time. It would be much faster and also more reliable than just covering parts of the film with sheet of black paper.

- One more - the fiber paper si supposed to be washed for cca 1 hour. How large should be the flow of the water? At the beginning I will be washing very few (and small, of course) prints at the same time and I do not want to waste more than necessary.

thanks.

Matus

Patrik Roseen
26-Jan-2007, 06:25
Hello,
yes there is the 'Kodak Projection Print Scale' than can be used, see following link
Kodak Projection Print Scale (http://www.adorama.com/KKPPS.html)

The sheet of plastic includes different dense areas and could be placed on top of the negative while making the testprint. The idea is to choose the most suitable area and adjust your timing according to information in this area. The print scale fits within a 4x5" negative so it could be used for contactprinting even this small size. Note: I have not used one.

I go by an old rule I picked up somewhere that the total amount of water should change every 5 minutes while rinsing. (Ofcourse, choose the amount of water in relation to the size of paper, i.e. no bathtub needed ;) )
There are also chemicals that claim to shorten the needed rinsing time. (Have not used this either.)

walter23
26-Jan-2007, 15:20
- Is it possible to buy some kind of test negativ with steps in density with which one can make at one shot the testing print - to get the exposure time. It would be much faster and also more reliable than just covering parts of the film with sheet of black paper.


I had a very simple setup when I was doing this. Setting up my bathroom for it is ultimately way too much hassle so I'm going to stop doing 4x5 contact prints. But here's what I did:

I had a small lamp (~40W probably, but one of those fluorescent tube low-wattage bulbs) which I had to drape a towel over and place behind me on the floor (below the printing area, which happened to be my toilet seat). It had to be fairly dim. I figured my exposure time by placing a book over the contact printing frame and moving it over (exposing a bit more of the paper) every 5 seconds. The point where the print first became pure black became my reference exposure (because it would correspond to pure black on a clear portion of the negative) - e.g. if it was the fifth strip from the lightest that turned black I'd know it was 5 x 5 seconds = 25 seconds. Then it's just a matter of trial and error for each print you do, though generally once I found the right timing (which in my case, with my light setup, was about 35 seconds) I could usually get it right on the first try, sometimes with a bit of adjustment if I had a particularly thin or dense negative.

As for variable contrast paper, yeah, you could use the filters. It's all about the colour of the light hitting the paper. You need to use a light bulb that has a fairly broad spectrum, I'd guess. I'm not sure if regular tungsten bulbs would work for this. I've heard it suggested that you could rig up a little light box out of cardboard or something, and include a place to slide in a filter, so that only filtered light is spilling out into the room.

In my case I was bouncing off greenish walls, whatever that does to contrast on ilford MG paper. I wasn't too worried about contrast becuase I was contacting printing just to preview my negatives. I've switched to a make-shift DSLR copy-stand with a light box to get digital previews, which is much easier to set up and less messy and gives me better results. If I had room for a dedicated darkroom I'd probably already have a 4x5 enlarger by now, but the reality is that this isn't feasible for me.

Colin Robertson
26-Jan-2007, 15:36
Matus- you're in Germany, yes? Try www.novadarkroom.co.uk and search for the 'delta projection scale' . It helps with exposure testing. Also- if washing fibre paper use a wash aid. There are a few to choose from (including Ilford). The current Ilford advice is, fix 1+4 for 1 minute, running wash 5 minutes, wash aid soak 10 minutes, running wash 5 minutes. As for drying flat, forget it. Fibre paper almost always curls. I put mine between boards and pile 60 or 70 kilos of weight on for a few days. How does it work? You'll see one of my prints in the exchange.

John Kasaian
26-Jan-2007, 20:45
I avoid the stuff, but most multigrade paper I've used acts like grade 2-1/2 without using any filters.

A projection scale is nice, but you can also use a piece of craftboard held over the print and remove 1/2" or so of coverage every couple of seconds gradually exposing more of the paper to the light (would this be considered a 2-finger step tablet?)

For drying your prints, you can get a plastic comb bound book of blotting paper from photo stores. Put your prints in the book and wieght the cover down with some heavy books or a cast iron skillet.

Good luck!