A quick question that I hope that one of the group has an answer to (PE maybe?).

Years ago, I used the ruby red 616 for masking with Kodalith and other films. My concern is applying it to another application and for that I need to know a certain specification for it--namely if a pure white light source were to be projected through it, what would its color output be in nanometers within the visible spectrum?

It's arcane trivia time!:p

Why not contact 3M. Many years ago when I was buying some of the more esoteric tapes from 3M there was all sorts of information available from them.

I have the PDF data sheet, but unfortunately all it gives is adhesion, composition, and tensile strengths. Several emails over the past week have gone unanswered--and this is a time sensitive project. We are presuming that the transmission wavelength is somewhat greater than 700nm, but knowing an exact wavelength will avoid expensive experimentation with multiple photodiodes and detector array circuits.

I used to use this tape years ago, and from my experience, it transmits red in the visible spectrum (ie-you can see it, much like a red safelight), but usually not in a frequency which will expose most paper, or blue or blue-green sensitive (ortho) films. This can be tested with the materials themselves, as you would a safelight.
You don't say what the purpose is, but years ago they made darkroom tools, like dodging and vignetting tools with a ruby plastic much like the tape, and you could see through them to guide their use, but they would block the right wave lengths for the paper.

Well, I was going to post the performance graph in the event anyone else ever needed this info. It's the same as the 1A ortho filter.

Can't upload it because my attachment quota is 1Mb--because after two years I ceased to be a subscriber and am now just an ordinary member--think I will stay that way too.

Far too much bureaucratic foolishness and micromanagement going on in this forum these days.

Far too much bureaucratic foolishness and micromanagement going on in this forum these days.

Apparently still good enough to troll for free information though.

Apparently still good enough to troll for free information though.


You get 10 extra style points along with your gold star for making that your post #1001 :D

Murray

Speaking of trolls there Mr. Banana :p

And of my 555 posts, about 400 of them have been to provide information to others in the group--most of the rest beating some emotionally charged dead horse philosophic or soapbox topic. Very few times in the past several years have I made information requests--and each time through the discussion myself and others have contributed to the general body of knowledge available here. Snidely remarks from a holder of the "council" title just serves as another illustration for my position. Sorry Murray :confused:

So as the rejoinder goes, "whatever..." :D

P.S. The transmission curve begins at 600nm, goes almost vertical at 610nm, and is at maximum through 700nm visible, trailing downward again in the IR segment.

There. I asked the question and answered it myself.