Night vision goggles in bound, a little help?

[Mike A]

Ok, I weighed my options, did a little research, bit the bullet and ordered the NVG that were recommended by are humble administrator as well as Ken Lee.

The thread regarding these seem to stop after Seans light table design (there was a url link here which no longer exists)
Has there been any design updates regarding the light table?

Should I order the LED IR light?

Can any offer any tips or techniques regarding DBI and NVG?

Thanks,
Mike A

 

[matt miller]

Mike,

I think you should try it out before you buy anything else. I bought the ATN Viper model (I think that's the one Sean mentions in his thread) and find that it works very well by itself. The built in illuminator seems to put out plenty of IR light. The front lens cap has a tiny hole in it. I usually leave the lens cap on for greater depth of field. The view through the monocle is more dim this way, but I can still see plenty to develop by inspection. I have also developed film with the lens cap off, which provides a much brighter view, but the depth of field is very narrow. I keep it on for the entire development time, sometimes 15 minutes or more, and have noticed no fogging or ill effects. It's really amazing being able to watch the neg develop right before your eye. I bet Sean's light table is even more amazing. Have Fun.

 

[Sean]

i am currently building a new light table for maximum brightness. It will house two of these units http://cgi.ebay.com/140-IR-LED-Infr...869408638QQcategoryZ48636QQrdZ1QQcmdZViewItem

both units side by side cover an 8x10 neg from edge to edge. overall the neg is about 4inches above the source. so light source, piece of translucent plastic, then glass tray, then neg. I found the smaller light source in my other thread failed to provide adequate detail as the neg became more dense. I only have 1 half of the current light source at the moment but it's VERY bright so looking forward to getting the other. Still zero fogging on the film from this. Just be sure you do not look at the ir lights with the naked eye, apparently it can blind you..

 

[Jeremy]

Have an extra battery handy, too. It REALLY sucks when you're developing and the "lights go out," so to speak.

 

[vet173]

I have the same NVG's. I made tanks out of clear acrylic so I can develop 4 at a time semistand. Seans light table is excellent for viewing negs by transmission, but looks like you are limited to doing singles. The built in light sources work just fine. When developing fp-4 in pyrocat, I can get right in and examine for shadow detail with no negative effects. I agree with Mike you have more depth of field, I use mine with the cap off. When close examining development, the area that I am concentrating on works good. Both ways work equally well. I would pick one or the other and stick with it. Switching between the two might vary your decision on when to pull. I turn mine off when the negs are just standing to conserve battery. They will start to dim down a little when batteries start to fade. At a certain point they will just shut down. It happened to me once already. When you notice they are a little dimmer than usual, it is a sign to me to put a battery in my pocket in case I have to change mid process, or just sacrifice the rest of the battery to be on the safe side. Murphys law says they will drop just about decision time. You will wonder how you ever got by without them before. It is that much of an improvement. Other will say you don't need them, and that could be true. With them you might be able to save the ones that you didn't know you had the wrong f-stop or any of the other things that seem to pop up. Now I don't have to keep N, N-, and N+ in seperate boxes. I even develope different films at the same time. Nothing like being able to do fp-4, hp-5, and acros at the same time. Although with acros I have to watch base side, others you can watch emulsion side.
As Matt said, have fun.
John

 

[Jeremy]

They will start to dim down a little when batteries start to fade. At a certain point they will just shut down. It happened to me once already. When you notice they are a little dimmer than usual, it is a sign to me to put a battery in my pocket in case I have to change mid process, or just sacrifice the rest of the battery to be on the safe side. Murphys law says they will drop just about decision time.

This is how it happens... they start to dim and then BAM! no more light. This reminds me that I still need to head out and get a couple of extra batteries.

 

[bobbysandstrom]

I love mine. I had a dupe neg that got mixed into some other negs. The original neg (timed development) was too contrasty. Since I had the IR device at a later date, when I spotted the dupe neg in the soup I was able to adjust my agitation and pull the film at the perfect time. I wear mine all the time and look at the film even when I'm processing by time. This way, I can learn exactly what to look for.

By the way, does anyone know the type battery and where to buy for this device? (Sean's) I'm being lazy.

Thanks

 

[Michael Kadillak]

I would caution anyone considering Seans option of a high number of IR LED's directly under a glass bottomed tray to do some serious testing before they "assume" that fogging is not a problem. I purchased a 32 LED IR light bank as a complimentary IR light source in my darkroom. I took a sheet of T Max 400 film and in complete darkness taped a strip of black electrical tape down the middle of the film and left the IF bank on about two fto three eet from the film for about 10 minutes and when I developed the film it was fogged all to hell. My conclusion is that when you can see a modest red "glow" from the LED bank there is a potential for a problem that unless you conduct testing on your own you might not even know that it is there. The larger number of LED's, the greater the risk IMHO. When I turn the light bank away from my film and bounce the IR light off of a light wall 6 feet away on the other side of the room I do not have a problem with fogging. Particularly with 400 ASA film DO YOUR OWN TESTING to validate your particular results. One dim point light source from your IR illuminator is probably acceptable but one should make absolutely sure.

These days I leave the IR illuminator off on my headset and use the remote IR source that is reflected off of a wall. I also have another 24 LED light bank covered by a diffused globe on a foot switch.

If you unintentionally add base fog to your film it is a steep price to pay and counterproductive. Assume NOTHING. Test your unit with your film and a densitometer (if you have one) and report your results.

 

[Mike A]

Michael thanks for the input on the IR LED's, I agree with your point and it only makes sense to test as we all use different materials and have varied conditions.

John, I'm using good old scheduled 40 grey pipe for my tubes w/caps in semistand but your acrylic tank sounds nice. Do you view your negs through the tank while they develope or do you pull and inspect them at 70% development time? By the way that monster 8x10 enlarger you posted is sweet.

Thanks for the help guys. I'll buy a battery and try it out before I pay $25.00 shipping for a $37.00 item.

Good light,
Mike A

 

[CRhymer]

Thanks for the help guys. I'll buy a battery and try it out before I pay $25.00 shipping for a $37.00 item.

Mike A

Still seems a deal for a source with a wavelength of 850m - unlikely to fog anything

Cheers,
Clarence

 

[vet173]

Michael thanks for the input on the IR LED's, I agree with your point and it only makes sense to test as we all use different materials and have varied conditions.

John, I'm using good old scheduled 40 grey pipe for my tubes w/caps in semistand but your acrylic tank sounds nice. Do you view your negs through the tank while they develope or do you pull and inspect them at 70% development time? By the way that monster 8x10 enlarger you posted is sweet.

Thanks for the help guys. I'll buy a battery and try it out before I pay $25.00 shipping for a $37.00 item.

Good light,
Mike A

Yes I can look right at them. Any color of chemicals does not show. In fact the presoak water is dark purple in the light but transparent with IR. I do my initial agitation, and look at each one at the end of that. If one is to be N- it will already have some development showing. I will put that one in front so I can watch it. When I agitate half way thru. I will put them in order of pull. When I pull the first one the next one will be up for inspection. Yep, that enlarger IS sweet. I've already made some 20x24's with it. I am also getting the hang of split printing. If you want to make some tanks. The INSIDE dimensions are 10.5x10.5x2.5. That is for kodak 8x10 hangers it uses 4L of chemicals. I semistand pyrocat-hd 1.5:1:200, so that works out to 30ml-A,20ml-b, water to 4L.

 

[Mike A]

Thanks John, I think I'll give the tank system a whirl. I tied using DBI in conjunction with semistand and 4 tubes, It got to be to much pulling them in and out to inspect. I can fabricate something from the local hardware or maybe http://www.usplastic.com/catalog/default.asp As for hangers I'm going to have to think of something for 11x14? maybe just use dividers like a film washer, any ideas?

Mike A

 

[Michael Kadillak]

I agree Clarence that on paper the wavelength appears to be beyond the range of concern, but why did my film fog when I tested it to a sampling of the output (clearly no closer than a tray above a light source) for a reasonable amount of time?

I would analogize this situation to safe lights. All sorts of companies produce a safe light, but you do not know if yours is truly safe until you conduct a safe light test under stringent conditions. It is one of the first steps in a Sexton workshop for a reason. Identical situation applies here as the variables are unique to each circumstance.

Cheers!

 

[Jeremy]

I agree Clarence that on paper the wavelength appears to be beyond the range of concern, but why did my film fog when I tested it to a sampling of the output (clearly no closer than a tray above a light source) for a reasonable amount of time?

What voltage were you running through the LED's? If you go past the recommended voltage you will have a spread of wavelength (I believe this is what was discussed in using the red bulbs as safelights and this would apply to the straight IR, too).

 

[CRhymer]

I agree Clarence that on paper the wavelength appears to be beyond the range of concern, but why did my film fog when I tested it to a sampling of the output (clearly no closer than a tray above a light source) for a reasonable amount of time?

Sorry Michael, it was just my pathetic attempt at humour. The ebay seller listed the wavelength as 850m (meters) the seller also uses mm on some other listings - IR wavelengths are usually listed in nanometers, or 'when I were a lad' millimicrons.

You are absolutely right - testing is the only way to be sure.

I bought an ATN Viper a couple of months ago based on useful information from Sean and others. It works great, but have only used it to load film so far. I am interested in the LED array, but as others have mentioned the emission spectrum may depend on other variables. The hint from Matt Miller to leave the lens cap with the tiny hole on to increase depth of field is much appreciated.

Cheers,
Clarence

 

[vet173]

Thanks John, I think I'll give the tank system a whirl. I tied using DBI in conjunction with semistand and 4 tubes, It got to be to much pulling them in and out to inspect. I can fabricate something from the local hardware or maybe http://www.usplastic.com/catalog/default.asp As for hangers I'm going to have to think of something for 11x14? maybe just use dividers like a film washer, any ideas?

Mike A

The only problem I see with anything you can get commercially is it will probably use a vast amount of chemicals. I made mine out of 1/4 in thick acrylic, so I could make them to the optimum size. I/8 in was to flexible. I always thought if I was going to 11x14 I would cut and expand some 8x10 hangers. Did Kodak ever make 11x14 hangers? A tank with dividers might work. I see a potential problem in that the sheets might lean up against the divider on the emulsion side. I would make the dividers about 1/2 in low so I could get to the sheets. I think the film is to flexy to just have a slot in the ends. I've seen uneven development sometimes when emulsion side is up against the hanger. Probably not a problem with normal or continuous agitation but I have had it with semistand, and compose acordingly. If I was to do 11x14 right now I would Probably use the tubes also. I agree that pulling them out to inspect would be a PITA. It would also defeat the purpose of stand development as you agitate to inspect. There goes consistency. Tray developing is always an option. I found I don't scratch film when I pull the bottom one out square with the stack, and bow the bottom center as I place it on top of the stack.Pulling out diagonally is where the corners were scratching my film. Downside is I would have to give up semistand. I don't want to give up the negs I'm getting now.

 

[vet173]

I claculated that for 11x14 you would need a tank 14.5x13.5x2.75. That would use 2 L of chemicals. That is based on the depth of the top of the hanger to top of film in my 8x10 hanger. My tanks cover film and an extra 1/4 in.

 

[htmlguru4242]

My conclusion is that when you can see a modest red "glow" from the LED bank there is a potential for a problem that unless you conduct testing on your own you might not even know that it is there. The larger number of LED's, the greater the risk IMHO. When I turn the light bank away from my film and bounce the IR light off of a light wall 6 feet away on the other side of the room I do not have a problem with fogging.

This is a problem; the lights DO have some output that is not IR, and Tmax film as enough sensitivity to pick it up (I've tried this). Reflected light is a good idea. The other thing that you can do is to put an IR filter over the LEDs to block out non ir light

 

[vet173]

I claculated that for 11x14 you would need a tank 14.5x13.5x2.75. That would use 2 L of chemicals. That is based on the depth of the top of the hanger to top of film in my 8x10 hanger. My tanks cover film and an extra 1/4 in.

My bad, they use 8 L my brain was thinking twice as much as my 8x10 version.

 

[Mike A]

I came up with these xray film hangers http://www.pnwx.com/Accessories/Darkroom/HandTanks/ when I performed a search for film hangers. Has anyone used these shown here with clips as opposed to the standard channel type hanger?

 

[Michael Kadillak]

I have used two sets of metal mangers for 8x20. One set is the static clip set where the clips are on each side of the film. These work OK, but it takes a bit of practice to pull and clip staying on the edge of the film to keep the film as flat as possible. A better alternative is a set of hangers I got from a guy in the UK that has two springs that pull in two directions to keep the film as flat as possible. In any event, the NVG assist greatly in this endevor.

Changing subjects, I want to point out that if you can see a red glow coming from your IR light bank or your illuminator, it is not 100% IR otherwise it would be invisible to the eye and also the film. It appears based upon my observations (not backup by scientific research - who has the time?) that a diffused glass surface has the ability to filter out a decent percentage of the adverse light energy that can fog film. I will conduct a few more tests and calibrate these results with a densitometer for a later post.

Unintentionally adding a few units of base fog with LED banks or an energetic IR illuminator is the practical equivelant of using outdated film and completely defeats the purpose of NVG. Yes, you can still make images that appear unaffected, but your density range needs to be compensated on the high end to make up for what you are adding to the film on the low end. Keep that in mind if you are finding that you are realizing less than optimal net film densities. Just my $0.02.

 

[MMfoto]

This IR DBI thing is really interesting to me. Has anyone tried to see if they could fog a high speed emulsion with the IR emitters? Or even a very high speed emulsion like TMZ, or Delta 3200 with it's extended red sensitivity?