If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|
Thread Tools | Display Modes |
#1
|
|||
|
|||
Light in darkroom ??
Hi guys,
I am going to start developing my own c41 color film. for loading the color film into the container.., can you use any color of lightbulb, or do you have to do it in a bag, totally dark. thanks, Kevin Rea Lancaster, Calif. |
#2
|
|||
|
|||
Light in darkroom ??
"kevinrea" wrote
Hi guys, I am going to start developing my own c41 color film. for loading the color film into the container.., can you use any color of lightbulb, or do you have to do it in a bag, totally dark. Totally dark. I think the only film with which you can use a light bulb (a red one, specifically) is orthochromatic, which is not red sensitive. |
#3
|
|||
|
|||
Light in darkroom ??
Howard Lester wrote:
Totally dark. I think the only film with which you can use a light bulb (a red one, specifically) is orthochromatic, which is not red sensitive. Kodak used to sell a dark green filter which could be used only for a few seconds after development was half complete. I think it was designed for panchromatic film, not color. A friend of mine had one in his darkroom, which was really the unfinished area under a staircase, which had a toilet and sink, so it was sold as a "1/2 bath". The light leaking in from the other room was brighter than the safelight. After that I never used one myself, and just did it by feel. I know the OP asked about color film, I'm not sure it would matter. The timing and temperature is critical not only for density but color balance. Geoff. -- Geoffrey S. Mendelson, N3OWJ/4X1GM/KBUH7245/KBUW5379 "Owning a smartphone: Technology's equivalent to learning to play chopsticks on the piano as a child and thinking you're a musician." (sent to me by a friend) |
#4
|
|||
|
|||
Light in darkroom ??
On 2012-10-10 02:05:05 +0000, kevinrea said:
Hi guys, I am going to start developing my own c41 color film. for loading the color film into the container.., can you use any color of lightbulb, or do you have to do it in a bag, totally dark. thanks, Kevin Rea Lancaster, Calif. Color film must be loaded into the tank in complete darkness. After the tank is loaded and closed, everything else is done in room light. -- Michael |
#5
|
|||
|
|||
Light in darkroom ??
Geoffrey S. Mendelson wrote:
Howard Lester wrote: Totally dark. I think the only film with which you can use a light bulb (a red one, specifically) is orthochromatic, which is not red sensitive. Kodak used to sell a dark green filter which could be used only for a few seconds after development was half complete. I think it was designed for panchromatic film, not color. I toured the Kodak Kodachrome development lab in Fair Lawn, New Jersey back when it was a serious operation. Probably in the late 1960s. Note that Kodachrome came in speeds of 25 and 64. Later there was a 200 speed version in 120 if I remember correctly, but I never saw that. I know that they had a dip and dumk machine for larger size film. I am sure they no longer made it in sheets. Maybe that was for E-6. Anyhow, some of the line operated in dim room light, but the beginning was in a totally black dark room. There was one of those dark green safelights in the top corner of the room, as far from the film loading station as possible. It did not put out enough light to see anything. It was just bright enough so when you dark-adapted you could see where it was. They normally left it off, but when they hired a trainee, they would turn it on just so the trainee could orient him or her self. Once they loaded about 1000 feet of the stuff on a light-tight roll, they closed the thing and passed it out through a light trap (double door setup where only one door could be opened at a time). That was stuck in the begin end of the line where it was washed, etc. Eventually it got to where the re-exposures were done and the color couplers were put in for three separate color development stages. You could see that, though the room was not brightly lit. I think by that point, all silver development was done and the remaining silver halide fixed out. They had an analytical chemist and a sensitometrist on duty all the time. They spliced a test strip after every so many customer rolls, and measured it and balanced the chemistry replenishment rates based on the results of those tests. They plotted the results over an extended interval so they could see trends before they became a problem. What amazed me was a separate line where the 1000 foot reels of processed and dried film were mounted in those little cardboard mounts. This was done by a team of women operating machines. Since each camera has a different pitch between the frames, and some cameras have irregular film advance mechanisms, this is done essentially by hand, but these women were so good at it that they could do a roll amazingly fast. The machine fed the new mounts, the yellow boxes where the slides went, the mailing labels, and so on. It also advanced the film, but the operator had a knob to align the edge of the frame with the edge of the mount. When they got some images where they could not tell where the edge of the frame was (too dark), they guessed (as far as I could tell). That part of the room was well lit, and perhaps a little brighter than normal. I bet they did not have to work an 8-hour shift though, because they would probably become less alert than required. Perhaps then they loaded film for processing or something. -- .~. Jean-David Beyer Registered Linux User 85642. /V\ PGP-Key:3EDBB65E 9A2FC99A Registered Machine 241939. /( )\ Shrewsbury, New Jersey http://counter.li.org ^^-^^ 09:25:01 up 9 days, 16:26, 3 users, load average: 4.81, 4.77, 4.79 |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Darkroom safe light | piterengel | In The Darkroom | 7 | February 9th 08 11:24 PM |
FA: The ESSENTIAL Black-and-White Darkroom Book -- the Kodak B/W Darkroom Dataguide | [email protected] | Darkroom Equipment For Sale | 0 | August 13th 06 04:02 AM |
FA: Darkroom equipment, Hot light, Studio equipment accessories | Gordon | Medium Format Equipment For Sale | 0 | December 7th 05 05:05 PM |
Can I use radium to light my darkroom ? ? ? ? | [email protected] | In The Darkroom | 3 | December 19th 04 10:52 PM |
Can I use radium to light my darkroom ? ? ? ? | Bruno Beam | In The Darkroom | 2 | December 19th 04 10:52 PM |