Densities of negatives

A 10x12 light table was purchased in order to see densities of different negatives at the same time. The photograph was made with a Canon and a basic lens. Edges of the table are less light so six different 4x5 glass plates don't photograph as well as they could, but they can all be seen together.

This marks a point of change. New work will soon begin. Getting glass to accept emulsion, exposing it correctly (?), developing it, drying and so on was the goal and it has been met.

New work will begin soon. A drape must be made inside the light tight darkroom door so I can leave plates out to dry. Larger plates must be learned how to be coated. The ultimate is 12x15, some day. And then I'd like to shoot and develop some more 4x5s, perhaps even make a contact print instead of scanning them all the time.

Strip Bracket Test

Bracketed Strip Test, f 16 @ 1 second each. A bright sunny day but not brilliant dry air, a slight haze, and it was humid. It was the same time and the same kind of sun as the last shot the day before. However, the Weston meter said 100 instead of 200; it may be inconsistent, I don't know. The Luna Pro, from the subject, pointed at the camera was 21. (That wasn't done right the first time). This file is not enhanced or touched up in any way. The negative is 4x5, glass plate, Liquid Light, Dektol 1:3, but development took 6 minuets. The plate was dried two full days and no prewetting had been done prior to developing. It developed by inspection, the edges got dark first and much later the center areas. I developed it until it showed the darker steps, one side was darker and there was tone in the other areas. The other plates were still damp when I developed them. This plate is the best pour so far. The camera was the Bender, and the lens 210 f 5.6 Caltar.

What is the correct exposure? What is the ISO? The middle one is f 16 @ 4 seconds. It looks dark.

More accurate measurements of the light need to be made. Fresh emulsion needs to be used. This batch had been heated up many times. It is too soon to determine exact ISO.

Exposure of Liquid Light emulsion

What is the ISO or ASA or speed of Liquid Light emulsion? Well, I got a pretty good picture at f8 at 1 second on a almost brilliant sunny day of average subject. The Sunny Sixteen Rule was applied to those factors. As it turns out, a brilliant day is 200 or 20 depending on which light meter you use. It does not matter what ISO you have to work with; all meters and cameras and lenses are based on this Rule: brilliant sun is gaged at f 16 at 1 over the film speed for the shutter. So, if you have 200 as the bright sun as on a Weston light meter, and 400 for a film speed, f 16 falls on 1/400 second for exposure. Lenses must be focused on infinity. Anything closer will cause the bellows to be extended farther, decreasing light intensity by the square of the distance. Infinity focus is required to start with in order to determine exposure using the Sunny Sixteen Rule.

My daylight and exposure fit the above information perfectly. ISO was ... the lowest setting on any light meter at hand. Get a Weston 715 just for the dial, the cell does not even need to work. Light was 18.5 on a Luna Pro or one block lower than 200 on the Weston. It looks like I'll be using the old Weston meter again.

The other part of the equation is developing the exposed plate in the darkroom. This is also standardized. Dektol is used, diluted 1:3, one part Dektol to three parts water. Mix according to directions on the package to get the one part. One minuet is used as a time. 69 degrees Fahrenheit is the temperature throughout. Agitation is minimal. Kodak Fixer is used to both stop the development and to fix. A small amount of Fixer is put in a tray and used as a stop bath for 30 seconds. The fixer tray has more in it and is used for at least 2 minuets. If milky white is observed in the plate, then longer time is required to remove it. 5 minuets of wash in water is all that remains. Plates are stood on edge on a paper towel to dry. Drying can take one hour to all day depending on how thick the emulsion is, dryer air and more of it speeds things up. I place the completed dry plate in a sealable plastic bag.

Washing comes first, Calcium Carbonate or Barkeeper's Friend are enough with a tap water rinse to get the emulsion to stick. I scrub the powder with a brush and a little bit of water over the plate in a tiny tray. Lots of tap water cleans it off. That is all that is needed.

Pouring plates every day

Pouring plates after cleaning them different ways is getting easier and easier. Exposing them is coming along, too. A Bender 4x5 camera was used in order to use the lens on it that has a cable release, a Caltar 210, and a Copal #1 shutter. Accurate exposures are in order. One of two plates came out great today. It was shot at f8 and 1 second; the light was not quite brilliant full sun, 18.5 on a Luna Pro meter. ASA or ISO is below the .8 lowest so is about 1/2. The plate was subbed with emulsion and fixed then coated again; it was thick and slow to dry. After scanning at 1200 I enhanced it, and touched it up a bit. It makes a very nice 8x10 print on the PC.

The emulsion is light and loose

The emulsion is very thin and light. It is also subject to humidity. As it is raining and very humid outside, it came loose. So, back into the oven with only the piolet light on to dry out then back into a bag. Perhaps it should be varnished after developing.

My First Plate

This is my first image. It is a 4x5 glass plate made with Liquid Light on top of Polyurethane water base high gloss (varnish). The whole thing lifted off, then dried flat again. Weird.
The problem today was to determine ISO. Tests were done on card stock first. This image is underexposed at 1 ISO instead of 1/2. One second was used at f 16 on a bright sunny day. Dektol was used at 1:3 dilution at 69 degrees F. developed two minuets instead of one because of the underexposure. It was scanned in the computer at 1200 dpi, auto adjust, unsharped, stiched, shrunk down to 20% at 300 dpi and posted as a medium sized image. A Pony Prime No.4 camera was used with a R.O.&C. Victor f8-5.6 lens.

All Together Now

Everything has been done, once. Chemicals were mixed, photographs taken, film developed, (glass broken), (emulsion peeled off and put onto another). The entire cycle has been done for the first time.
Now to do it again and again until it is done right.
The ice is broken.