Question About Development By Inspection That I've Never Figured Out

[Fragomeni]

Haven't seen those discussions for a while. The welder goggles with filters will work outside because you are subtracting light from the sun and looking at near-IR (Which creates that faint deep red glow on IR LEDs you see on security cameras, etc..). It's equivalent to putting a $50 IR filter on your camera and taking a peek. You won't see much, but your eyes should adjust. It's not relevant in a darkroom lit with IR LEDs, as you don't need to subtract the various forms of radiation from the sun. Longer wavelength than about 720-800nm if you can't see them in the darkroom with naked eyes, the googles aren't going to help. They don't change the wavelength; just filter out extraneous stuff.

I know the instruction for IR goggles you're referencing. Thats not what Im making. I'm working with a similar design but its basically the same thing as the childern's night vision toy that can be bought at Target or Walmart. All they are is a filter and IR LEDs. They work in the darkroom. A friend of mine has been using them for a while and has built goggles based on them that output more IR light and make it easier to see. I'm basing mine on his design. Using a densitometer, he's tested both the toy goggles and the ones that he has made and verrified that that they do not expose the film in the time that it takes to develop film.

[BetterSense]

I'm working with a similar design but its basically the same thing as the childern's night vision toy that can be bought at Target or Walmart. All they are is a filter and IR LEDs.

What toy goggles are you talking about? All the ones I have seen use low-resolution video cameras and electronic viewfinders.

[Fragomeni]

What toy goggles are you talking about? All the ones I have seen use low-resolution video cameras and electronic viewfinders.

There have been a few on the market over the past year or so. View Camera magazine did an article on using them which started a lot of discussion a while back. Thats where my friend got the idea and I think he probably uses the ones mentioned in View Camera. I think they're called EyeClops or something like that. There are numerous variations even under that name. They use IR LEDs and a filter to view through.

[Fragomeni]

Visit the AZO forum for more DBI discussions but bottom line you learn from experience, caveat emptor - don't learn with 20x24 sheets use 4x5 sized film instead.

Looks like a good amount of info on the AZO forum. Haha, I won't learn on 20x24! My 20x24 is almost up and running so I will hopefully be able to apply it to that down the road after I learn on a much smaller size film!

[BetterSense]

I think they're called EyeClops or something like that. There are numerous variations even under that name. They use IR LEDs and a filter to view through.

I think you are mistaken. They use a low-resolution camera similar to a webcam and an electronic viewfinder. I know because I have them.

[Fragomeni]

I could be wrong. I'll ask him what he has. The ones I'm talking about have no camera. We've taken them apart completely.

[Fragomeni]

jp498 and BetterSense, you guys were both right. I was mistaken. Just got off the phone with my friend. He is using the Eyeclops and confirmed that it does have the camera as BeterSense described. He also clarified that what he dissected and modeled a homebrew pair from was a more basic goggle without the camera. It does see IR light but because it doesn't have an IR illuminator (part of the camera) it only sees the LED bulbs and not much is illuminated by the IR light. Because of this clarification I'll probably nix the idea of making a pair especially since he said the toy was much better then the pair he made (because of the intensifier).

I know I can pick up the EyeClops online but these look very promising and are higher quality with a much larger screen. Just ordered a pair and will update with the results. The reviews knock it but that seems to be because people are trying to use them for tactical things which they clearly aren't designed for. They seem promising for the darkroom worker.

[Bill Burk]

That sounds like a good thing. At least you won't be burning your eyes out...

Wonder what colors it is going to display... And is it really safe for film...

Looking forward to hearing how it goes.

[Fragomeni]

The set I bought uses an IR camera to relay the image into a large viewing screen inside the goggles much like the EyeClops toy that so many have had success with. I opted for the goggles that I purchased because of their low profile (they don't stick a foot out in front of you like many of the higher end military spec goggles), the large clear viewing screen, and the fact that they use the same technology as what I am most familiar with and what I know has been used successfully. Also, they are not damaged if hit by direct sunlight like many of the high end goggles that use light sensitive cells. My main concern with them is making sure that no visible light reflection spills out from where the goggles meet the face. If I have to work on them a bit to ensure a seal to the face I will do that. Given that they work by illuminating a a set of IR LEDs (and then using the intensifier technology in the camera to render the image of the screen) like the EyeClops and similar devices and given that these are a more serious device then the toy I feel pretty safe with the LEDs being true infrared and as long as they are then they should have no effect on film.

[Fragomeni]

Did a little research. The Nyte Vu goggles use 850nm IR LEDs (which will give a faint red glow), not as high as I was hoping. I did a little more research and found that the EyeClops goggles, which I know have been tested to work and have no exposure effect on film, have 830-850nm LEDs. Perhaps 850nm is in fact far enough out of the sensitivity range of film that it wont be an issue but I will most definitely be testing this with my densitometer to be certain. Just to be safe, I may try blocking the LEDs with a thick enough filter to block the faint red glow but still allow the true infrared to pass (if thats possible). I also found a video showing that they can see 940nm IR LED light but the image is slightly grainer. I guess this is because the higher nm light is beginning to exceeds its range. If disassembly is easy, replacing the original IR LEDs with 940nm IR LEDs shouldn't be difficult.