Thursday, June 30, 2011

Better work

Liquid Light with photoflo in it on 4x5 plates.

Monday, June 27, 2011

Lliquid Light bracket test

Liquid Light emulsion on glass was applied with thicker glass edge strips. My son and I went to the park to expose it in a long shot of some trees across the grass at mid day. Exposures were an unknown to me; past experience told me that ISO could be 1/2 to 2 according to instructions but to my trials with one year material was ISO 10.

This emulsion is new. Exposures varied from 1/4 second to 7 3/4 seconds. The slide was pulled out all the way, a one forth second shot was made, the slide was inserted and pushed over some, then following exposures were 1/2, 1, 2, 4. Foot Candles were one block under 320 by a reflected light reading.

I used to pull the slide out and expose 1/2 second shots or 1 second shots. This was new. Good thing I had a solid 1/4 second exposure covered because that is the one that was correct.

Development was only one minuet in Dektol 1:3. It could have been over three minuets long.

Friday, June 24, 2011

Dry Plate Cameras

There are today two cameras for sale on the web, e-bay from the UK. One is a 10x12 and the other is a 8x15. Each has a film holder but no tripods are included.
The man I bought all mine from in India,, has some for sale today. They are the same kind of Vageeswari cameras. I did a search for Vageeswari in film cameras on ebay.
The sellers name is photolud if you are interested. He has had these ULF dry plate camera offered for a long time. They look good to me. I'm not ready to sell mine. I want to use them. I wrote photolud and told him that I now can coat glass plates for such cameras. He was listing film sources and foam inserts to use film. HA. No one knows how to coat plates that big. I want everyone to know how to do that.
Here is how to coat large format glass plates. Sand the edges smooth. Use single strength glass. Clean the top with Calcium Carbonate and grain alcohol; I use a 1 inch brush and paper towels. Rince all dust off and polish with towels, wash with alcohol and don't touch it. Have edge strips made out of plate glass that is the next size thicker and have those edges smoothed; strips should be about 4 inches wide and longer and wider so they can overlap. Butt the edges of the edge plates and leave a gap where the plate is inside the 'well'. Have one more edge strip ready to scrape emulsion with. It should overlap and ride on the edge strips. Heat it. Melt Liquid Light at 110 degrees F, pour it inside the well all over and scrape it down one time. Practice with buttermilk first and measure out how much to use. Excess is easily recovered from the wide sheets surrounding the plate. Oh yea, the glass assembly is set on a damp cloth or rubber matt. Emulsion has a way of getting under the glass and a way to lift the glass is needed. The flexable backing peels off the glass.
That's about it. I couldn't believe how easy it went on.
Be careful how and when you take it apart as the emulsion needs to stay on the edges of the plate. It doesn't cut well and rips easily. A razor blade if stainless could be used to remove excess after dry some.

Thursday, June 23, 2011

A New Book

It's kind of hard to find how to publish a blog; try looking for blog2print. I had a book made of all the previous pages in this blog. Considering the effort involved in doing it myself it is well worth the price.
This posting is the introduction to the second part of my work. Now I am able to coat large plates. Before, I was learning how to do that with small plates. Yesterday I photographed with the Korona View 8x10 camera and developed the plate. Here is what I got.

My main objective was to get a plate exposed and processed that I had coated. The other objective was to develop it in the center of the time scale so I could pin down the ISO.
A bracketed test plate 4x5 had been made; five exposures of one half second each were made; all of them showed image, and I chose 2 seconds for the 320 foot candles earlier in the day when the sun was on the side of the houses. It moved while I got the big K ready; that is a story in itself. The sun went behind some clouds so the foot candles dropped to 160. I used 4 seconds at f 6.3 or 2 1/4 ISO according to the test. Development for the test was in Dektol 1:3 for 2 min. 22 sec.. That is a lot. It was a thinly applied coat and went dark immediately. The Dektol package says 3-4 min starting at 3/4 sec.. If you make a scale of numbers every quarter second there are 14 in all and 7 to the center.
3/4, 1, 1 1/4, 1 1/2, 1 3/4, 2, 2 1/4, 2 1/2, 2 3/4, 3, 3 1/4, 3 1/2, 3 3/4, 4
Two min and 22 or 23 seconds was the center. If only three min. would be used as the maximum time in developer then less than two minuets would center. I think fog may increase with development but I used the longer scale anyway. I wanted to see how it would effect very light exposures.
The image was grossly overexposed. ISO may be 6 not 2 1/4 when developed to the center or 2 min.. I stopped development at 2 min..
If I had developed by inspection instead of time I'd have pulled the plate out in 30 seconds while there were still lots of lights showing in it. However, now I have a benchmark to gauge further work.
A Dark plate means less light is needed, If one processed to the center of the development scale.
The emulsion used was Formazo which is not made anymore at least as far as I know. It was applied thinly with an emulsion well.
Later on I'll try to make better photographs. This is incredibly dirty as well. I don't mind. Bigger contact prints won't show what a computer can see.
new note: the longer time of 4 min in developing is used in developing fiber based paper. 3 min is quite enough to do plates. 1 min is recommended for RC paper and 2 for Fiber based paper. One minuet is about right to develop plates with. I may have been developing too long.

Monday, June 20, 2011

8 x 15 plate coating

How I coat 8x15 inch glass plates with Liquid Light emulsion. Single strength glass was used from the glass store. I had them polish the edges. The glass fits into a book form plate holder for a Vageeswari camera.

Double strength glass is thicker than single strength glass. I had some and cut edge strips out of it. They should be at least 4 inches wide, two are longer than the others. The sharp edges were taken down with emery cloth. Wet o dry paper would be better to use wet.

The thinner single strength 8" x 15" glass photographic plate was cleaned with Calcium Carbonate and Everclear grain 151 proof alcohol. It was rinsed with tap water, held with paper towels, and wiped off. It was then cleaned only on the top with Everclear. It was handled carefully using paper so as not to touch it at all with bare fingers.

The plate was laid out on a flat table on a sheet of rubber matt. The thicker glass edge strips were laid out around it with 1/8th inch gaps between the plate and the edge pieces but without a gap between where edge pieces touch each other.

Buttermilk was used in daylight to see how much emulsion it would take. 2 1/2 ounces did the job. Buttermilk is very much like emulsion and cleans up easily. One 35mm film canister holds about an ounce of emulsion if it is totally full. Nevertheless, I used three full canisters of Liquid Light emulsion; it is better to have some left over than to not have enough.

Three cold and solid full 35mm film canisters loaded with Liquid Light emulsion are placed into a quart measuring cup that is filled with 120 degree F water to melt. A 'nose' pot and a glass "puddle pusher" rod are placed into a tray with hotter water in it so they can warm up. When things are taken out of the water they are dried off and they quickly cool. The water in the measuring cup cools to 110 F; the top is taken off a canister and the emulsion is checked with the thermometer probe to see if it has melted completely.

In the dark, with an amber light on, the emulsion was poured first into the 'nose' pot, after it had been dried, then out onto the plate in long s curves with little spaces between the runs. The emulsion was pushed from one or two inches inside the plate out towards the near narrow end to start and make sure that end was fully covered. Then, I started the scrape out on the thicker edge piece and pulled the rod slowly and lightly all the way to the other side. One swipe did it. Excess emulsion piles up on the wide edge piece.

I was lucky the first time and the plate covered completely with one swipe. However, the second time four swipes were needed; good thing it was hot. The excess was push back onto the plate and dragged to the other side. Three cans were almost completely used up. It is best to do it in one pass. Multiple passes creates uneven exposures. Use one application no matter what. Uneven application, as in pouring, can be remedied if the glass is heated like when I put hand poured smaller plates onto heated stone to allow uneven cooling emulsion heat back up and spread out. 4 canisters in a small measuring cup may be better because it comes out faster and 3 didn't cover on the third attempt at coating a plate in one swipe.

Excess and spillage soon gelled and was taken up with a new razor blade, and an artist's palette knife, and returned to an empty film canister.

The plate looks great. It was set onto three wooden dowel rods in a cardboard drying box of shelves. The wet back would stick to the paper and be very difficult to remove otherwise.

This method is very easy to do and gives excellent results. The edge pieces and rubber mat and glass rod may be used over and over. Actually, a glass rod isn't even needed I bet. I'll need to use a flat piece of glass with a polished edge to coat larger plates because a longer one is needed to cover and I don't anticipate any different results. The glass strip can even be heated first and that will help. Glass on the rubber matt was room temperature. It coated great. I'm happy.