Agfa Portriga Speed paper sensitive to red light?

ericzhu

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Just got a leitz V35 enlarger and thanks to the seller, also a pack of 12'*16' Agfa Portriga Speed 3 paper.

So I test my first pint with the paper. I bought a red bulb, but all test paper strip are turned to total blackness in the red light. I doubt the paper is sensitive to red light, so I turn the red bulb off, it works. But it comes another problem, there seems fogging in the paper. The frame of paper is not white, but grey (http://www.fotop.net/ericzhu/summar/sample_photo) . I doubt this may be due to the long storage of the paper or the base color of paper is not white.


May I ask the following 2 questions:
1/ Would the paper expose to the red light?
2/ Is the base color of paper not white?
 
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The "red" bulbs which you get from hardware stores (and not designed with darkroom use in mind) aren't really safe for darkroom use. They may look red, but they would also emit blue and violet rays as well. Real darkroom safelights emit genuine spectral red, so no fogging occurs. Which lamp did you get?

To test for lamp 'safeness' do this simple test: lay a piece of paper inside your darkroom, illuminated by the lamp in question. Have a piece of coin on it. After more than 5 minutes exposure, develop the paper. If you see lighter, round pattern on the paper (where the coin lay), the lamp isn't safe and fogged the paper.

As ManGo said, lamp brightness and distance is critical. A 15 watt safelight is designed to be safe if its at least 1 metre from the paper. Any closer or a longer than necessary exposure will cause even the safest safelights to cause fogging.
 
Also, check for other sources of light leaks (door, windows if any, enlarger).
 
Thanks all. I would buy a real safelight. As for the light leakage, I feel that a little slice of light is leaking up the negative holder. Does it matter?
 
If the sheet of paper is under enlarger already when it's on, it shouldn't matter.
 
There are chemicals you can add to hold back the fogging. I forget what they are.
Benzotriazole and potassium bromide. However, if you use out of shelf developer I don't think that make sense. First of all you don't know the developer composition and which chemical is better to use, secondly it's hard to buy just 1 gr of benzotriazole.
 
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