Thomas Duplex or Adorama/Zone VI LED Safelights

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I'm setting up my first (and I hope last) B+W darkroom. I've bought Saunders VCCE Enlargers and V-Track Easels. Versa-lab Print Washers and Schneider Lenses. All I need now are timers (I'll probably get Saunders 3 digit LEDS) and Safelight(s?). Since I've never even seen one what I'd like to know is what experience anyone has with Thomas Duplex. Are they safe for _all_ B+W paper? Are they instant on or do they have to warm up? How long does warm up take? Are they as bright as I've been lead to believe? How long does the bulb last? Since my darkroom is 20 X 15 ft would it be better to use two (or more $) smaller safelights? On that track has anyone used the Zone VI LED safelights from Calemut or the screw base LED Bulb from Adorama? Would two Zone VI's or 4 to 6 Adorama's do a better job then one Thomas Duplex? Thanks Jim Vanson

-- Jim Vanson (primary_colors@hotmail.com), November 10, 1999

Answers

I hope you do not mind too much, if I'll give you a basic intro into safelights. As I can not refer to the mentioned lights as I simple use old Agfa filters with a 3 W halogenlight.

Usually, common b+w papers can be divided into two groups: - sensitive to blue light, unsensitive for 500 nm + - sensitive to blue and green light, unsensitive for 570/580 nm +

First group includes fixed grades e.g. Ilfospeed, Agfa Brovira Speed. Second group includes vc papers, Ilford Multigrade, Oriental VC, Agfa MCP, Kodak Polymax.

Most paper companies have published sensitivity versus spectral wavelength (nm)on their webpages, e.g. Kodak. So one may look up his choice of paper for exact data.

First group papers can be used with green/yellow filters, like Kodak 0A, this lights are relativlly bright, data sheets usually say 4 ft. distance 15 W light bulb for 2-3 mins.

Second group papers can be used with orange filters or dark yellows, usually orange filters are brighter, also 4 ft., 15 W, 2-3 mins. (I found out that Ilford Multigrade can work with indirect green-yellow for a quick handling, while Oriental definitly will not work with green-yellow.)

If using papers from both groups, consider a orange unit, maybe with a interchangable filter for green-yellow for extra brightness, using group one papers.

For testing safelights please refer to the Kodak publication "How is safe is your safelight?" available on their webpages.

Regarding warm up:

Hot lights like tungsten etc. change their emission spectra during warm up, they are shifted towards lower energy (this means higher nm values) which is no problem with papers as they are unsensitive to higher wavelengths.

Regarding brightness:

Your eyes will adjust to it.

Number of safelights:

30 sq.metres is rather large compred to my 6 sq. metres, so how about a smaller direct light and a bigger indirect light, I leave this question better to the folks with big darkrooms!

Summary:

Model: "Uhh, it is so dark in here!" Answer: "Guess, why it isn't called lightroom" (8^]

Wolfram (Different continent, different safelights)

-- Wolfram Kollig (kollig@ipfdd.de), November 11, 1999.


I've used the Thomas Duplex for about 15 years. Same bulb (or what ever is inside them). I've not found a paper yet that it fogs, including VC. There are also filters for inspection of panchromatic film and papers which I've never tried. Warmup time is about 10 minutes, but you can use it with reduced light output while you're waiting. You will definitely only need one, sometimes it's so bright that you have to let down the flaps to focus. It's very heavy. In 50 years (of buying great sounding stuff that doesn't work), this has been one of my good ideas.

-- Bill Mitchell (bmitch@home.com), November 11, 1999.

I purchased the Zone VI last year and just love it. Prior to that I had used small 5x7 safelights with filters that needed to be changed every six months. That filter fade made the degree of safeness vary over time and at the cost of replacing the filters the Zone VI became a less expensive light over the course of a few years. I have a few friends that have the Thomas light and they think that they are great, they have to justify the expense. In written reports that I have read the Thomas is not always a very safe light, VC paper is really sensitive.

-- Jeff White (zonie@computer-concepts.com), November 11, 1999.

View Camera magazine did a safelight test about a year ago when the Zone VI came out. From what I remember, the Thomas light and the Kodak light both fogged variable contrast paper. The recommended 4 feet for the Kodak light turned out to be way too close. They liked the performance of the Zone VI light. It might be worth tracking down the article.

-- John O'Connell (joconnell@adelphia.net), November 12, 1999.

Anyone tried stringing some red LED's together to make their own safelight?

Given that they typically have a ~650nm wavelength, it sounds like they should be right for all papers.

duncan

-- Duncan McRae (duncanm@zip.com.au), November 14, 1999.



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