ATN Viper Night Vision Goggles - I thought I might be getting fogging

[axs810]

I bought these wanting to try it out but once I used them I noticed I kept getting a slight fogging on my film when wearing this unit. I cannot figure out why I am getting a very light fog but it keeps happening very slightly and with what seems to be a more pronounced grain structure. (I develop 320txp for 4:30-6min in HC110B)


Things I have tried-
- Keeping the cap on while using night vision (the one that is like a pinhole cover)
- Taking the cap off and covering the IR light with a napkin
- Keeping the night vision unit close to my face to prevent light from bouncing off my face and onto the film


I wear the unit and watch the film develop the whole time could that be my problem? Also, I manually focus the lens and look at my trays does everyone else do that? Just curious because I know everyone else has good luck with these so I know it's probably something I'm doing wrong but can't seem to figure it out. Help me? :confused:

[Drew Bedo]

I don't know anyting about these goggles specifically, but . . .any "night vision" technology must use some light energy to produce a visable image. the light amplification or "starlight" technology uses feint ambient light in the visable range . . .moonlight or starlight . . .but there must already be some amount of visable light to be amplified.

The IR technologies use infra-red energy in wavelengths too long to be visable to the human eye, and converts that into wavelengths in the visable spectrum . . .usually green. Your goggles may have an infra-red illuminator shining onto the film.

Perhaps your film has an IR sensitivity. Another guess is that the fog is caused by the green light coming rom the eyepiece end of the equipment.

[Bob Mann]

I have been using Vipers for a few years and have a few thoughts:

I wear the unit and watch the film develop the whole time could that be my problem?

Are you tray processing? Or using dip tanks? I use vipers with dip tanks and have never had an issue with fog. I have also done tray processing without problems.

Taking the cap off and covering the IR light with a napkin

Not sure how much a napkin would cut IR output from the LED, the lens cap should have no affect - I leave my lens cap on most of the time because of the greater depth of field.

Have you looked around your "darkroom" with the Vipers on for other light leaks?

seems to be a more pronounced grain structure

Wouldn't grain be the result of chemistry, not IR exposure? Are you using a different developer?

[jasonphoto01]

Are you using night vision or infrared? What model goggles are they?

[sun of sand]

Before I tried night vision I used to use the green illumination from a watch dial in short bursts throughout development to watch it progress

I never noticed any fogging.

I'd think that fog much quicker than the goggles so I'd look elsewhere first

[Ken Lee]

You might find it helpful to do a rigorous test to find out if the film is fogged already, if the IR device is responsible, both or neither.

First, get 2 sheets of film which have never been subjected to illumination from this device. The best choice would be a brand new box of film, unopened and therefore not previously fogged. This presumes that your darkroom is light tight.

Cover 50% of the first sheet with someone completely opaque like a book. Subject the first sheet to illumination from the device, at the distance you typically work. Do this for 10 minutes.

The second sheet should come right out of the box, never exposed to anything at all.

Next, in total darkness, process both sheets in the usual manner.

Next, compare the 2 sheets. If no fogging is present, they should look the same. If there is fogging from the IR device, you will know how much. If the film is already fogged for some other reason, you will know that too.

Without a rigorous test, your efforts may be just... speculative.

[Harold_4074]

A slightly more rigorous test would involve deliberately fogging a sheet of film to barely detectable density, then performing the half-and-half exposure test as described by Ken Lee.

In a real camera, there is always some scattered light, which is usually lost down in the base-plus-fog region of the characteristic curve (deep in the "toe" region). Adding a very small amount of additional light may being the exposure up onto the curve far enough to be objectionable, even though that exposure by itself on otherwise pristine film would not be noticeable. (This is the rationale behind the Kodak safelight testing procedure, discussed at great length elsewhere.)

[axs810]

Bob Mann: I have been using Vipers for a few years and have a few thoughts:


Are you tray processing? Or using dip tanks? I use vipers with dip tanks and have never had an issue with fog. I have also done tray processing without problems.

I am tray processing.


Not sure how much a napkin would cut IR output from the LED, the lens cap should have no affect - I leave my lens cap on most of the time because of the greater depth of field.

Have you looked around your "darkroom" with the Vipers on for other light leaks?

I clog the napkin over the LED until I can't visibly see it with my naked eye. The napkin kind of acts as a diffuser in case it was fogging I would be able to see a difference but that idea didn't really help too much. When you mention leaving your lens cap on to get a greater depth of field what do you mean really? When I look through the lens cap its like trying to look through a hole the size of a toothpick but when I take it off I can adjust focus and get a 5x7 tray size view of what I am doing (in focus vs with the cap fuzzy focus toothpick hole)

I have looked around my darkroom with the night vision on and found no light leaks.


Wouldn't grain be the result of chemistry, not IR exposure? Are you using a different developer?

My bad I just remembered that once I found out I was getting some fogging I bought a box of hp5 so I wouldn't waste my precious 320txp. So I was thinking about the wrong film but did still have a very weird look to it. The negative looked like it had some sort of base exposure over the camera exposure which resulted in looking like the negative had more pronounced grain everywhere but might not have.

[axs810]

Are you using night vision or infrared? What model goggles are they?

ATN Viper Night Vision Goggles with IR Illuminator. I got the same one that's on Ken Lee's tech website.

[axs810]

Before I tried night vision I used to use the green illumination from a watch dial in short bursts throughout development to watch it progress

I never noticed any fogging.

I'd think that fog much quicker than the goggles so I'd look elsewhere first



I have looked elsewhere and still couldn't find an answer so I came here. I usually spend 20 min making sure my bathroom is light tight then when I am certain I have someone close me in by taping black out plastic clothe over the outside of the door while I do the same to the inside.

[axs810]

You might find it helpful to do a rigorous test to find out if the film is fogged already, if the IR device is responsible, both or neither.

First, get 2 sheets of film which have never been subjected to illumination from this device. The best choice would be a brand new box of film, unopened and therefore not previously fogged. This presumes that your darkroom is light tight.

Cover 50% of the first sheet with someone completely opaque like a book. Subject the first sheet to illumination from the device, at the distance you typically work. Do this for 10 minutes.

The second sheet should come right out of the box, never exposed to anything at all.

Next, in total darkness, process both sheets in the usual manner.

Next, compare the 2 sheets. If no fogging is present, they should look the same. If there is fogging from the IR device, you will know how much. If the film is already fogged for some other reason, you will know that too.

Without a rigorous test, your efforts may be just... speculative.


Alright I'll get on a test right now and report back in awhile.

[Ken Lee]

Excellent.

It's important to not deal with film that you've loaded into holders, exposed, and removed from holders.

If we want to determine if the IR device is fogging, we need to remove all the other variables.

[axs810]

Alright so I have some good news! I was wrong the ATN Viper Night Vision goggles don't fog film! :)

For this test I didn't go out and buy brand new film because of personal limitations but it didn't matter.

Here is what I did:
- Sealed off darkroom using Delta 1 Black out plastic + unscrewed lightbulbs in bathroom
- Sat in darkroom for 5 min and couldn't see any light coming in so I put on the IR goggles and looked around..nothing I could see so I started
- pulled out one new negative from the box (hasn't been exposed to light, loaded in a film holder, etc just pulled out and thrown in developer)
- I let 5 min go by then put it in the stop and fix - resulting negative is clear
- Next I take a new negative out from the box (hasn't been exposed to light, loaded in a film holder, etc julled pulled out and thrown in the developer)
- 5 min go by as I stare at the negative with the IR Goggles then put it in the stop and fix - resulting negative is clear or the same

BUT as I'm fixing the last negative I turn around and notice the Delta 1 black out plastic isn't fully blocking the out light anymore...so I asked someone to check the outside and see if it was still sealed. It was sealed perfectly but there was just barely a little light coming through the plastic and now I think I know how my film got fogged before. My bathroom doors have a big enough gap around the edges so it allows light to creep through the cracks of the frame. When I develop my film I sometimes do 3-4 batches of 5 in a row. So maybe I was in there for too long and that very small amount of light coming in through the plastic slowly fogged my film. My bathroom doesn't have any windows so the door is the only factor I can think of...



This is the Black Out Plastic I use.... *thumbs down*

http://www.freestylephoto.biz/423416-Delta-Blackout-Plastic-4-ft.-x-16-ft.-roll

[Ken Lee]

That's good news !

[Tin Can]

Alright so I have some good news! I was wrong the ATN Viper Night Vision goggles don't fog film! :)

For this test I didn't go out and buy brand new film because of personal limitations but it didn't matter.

Here is what I did:
- Sealed off darkroom using Delta 1 Black out plastic + unscrewed lightbulbs in bathroom
- Sat in darkroom for 5 min and couldn't see any light coming in so I put on the IR goggles and looked around..nothing I could see so I started
- pulled out one new negative from the box (hasn't been exposed to light, loaded in a film holder, etc just pulled out and thrown in developer)
- I let 5 min go by then put it in the stop and fix - resulting negative is clear
- Next I take a new negative out from the box (hasn't been exposed to light, loaded in a film holder, etc julled pulled out and thrown in the developer)
- 5 min go by as I stare at the negative with the IR Goggles then put it in the stop and fix - resulting negative is clear or the same

BUT as I'm fixing the last negative I turn around and notice the Delta 1 black out plastic isn't fully blocking the out light anymore...so I asked someone to check the outside and see if it was still sealed. It was sealed perfectly but there was just barely a little light coming through the plastic and now I think I know how my film got fogged before. My bathroom doors have a big enough gap around the edges so it allows light to creep through the cracks of the frame. When I develop my film I sometimes do 3-4 batches of 5 in a row. So maybe I was in there for too long and that very small amount of light coming in through the plastic slowly fogged my film. My bathroom doesn't have any windows so the door is the only factor I can think of...



This is the Black Out Plastic I use.... *thumbs down*

http://www.freestylephoto.biz/423416-Delta-Blackout-Plastic-4-ft.-x-16-ft.-roll

I used the same Delta Black out Plastic, but I did it differently.

I had 80 sq ft of direct southern exposure with clear glass brick. My first layer was a combination of silver reflective insulation over foam core, not fully light tight. Inside the window space I left Chicago made objects for street side viewing including a complete Schwinn bike, like time capsule.

Then 1/4" plywood on studs 12" from glass block. I carefully covered that with the Delta product, taping all seams and corners. Finally I covered the Delta with 5x16" pine tongue and groove, some gaps.

I test by sitting for 20 minutes and see no light or glow at all even with direct sun.

If it ever leaks. I will apply another layer of Delta and paneling.

I gained a full black out darkroom, soundproofing and insulation.

Since I sleep in the far corner with every light source off, I wake to full cave and it takes a while for my eyes to adjust.

The weird thing is the stuff I see just after awakening with eyes wide open. It's like a dream but I 'see' photographic type images that are constantly different. I am not seeing the room contents, but people, as if in posed portraits. I don't know them either.

Then I bring on the day with a slow rising dim light, manual control. No alarm clock ever used unless absolutely necessary. Like today for Dr appointment. :(

I used to use an Astronomic timer (https://www.1000bulbs.com/product/97760/ELEC-HB880R-SP.html?utm_source=SmartFeedGoogleBase&utm_medium=Shopping&utm_term=ELEC-HB880R-SP&utm_content=Intermatic+Electronic+Astronomic+Timers&utm_campaign=SmartFeedGoogleBaseShopping&gclid=CIfx0puIrMYCFdccgQodqFUADw), but I dislike not being able to sleep in. However I still use it for my HEPA filter as the noise is best tolerated during REM. I may be setting a natural Astronomic rhythm from noise not light.

Any light while sleeping now bothers me...

I like the dark.

[axs810]

I wish I could set up something more permanent like that but unfortunately my set up has to be able to put up and take down quickly. If I did have to battle any windows though I do like your idea of the silver reflective insulation over foam core along with the blackout plastic.

[Bill Burk]

axs810,

Glad you found your light leak. I did a test with a step wedge and a long exposure to close proximity to the full-intensity IR light (TMY-2).

Based on those results...

I chose to "attenuate" the IR light with a piece of silver film with density 0.60 (note E-6 slides are completely transparent to IR so it must be silver film or some other light blocking material that really blocks IR). I found an old negative from a rodeo that I could spare where the arena dirt was 0.60. So I cut the negative in a circle and glued it to the light with contact cement. Occasionally it falls off and needs re-gluing but that's all the maintenance it needs.

http://www.largeformatphotography.info/forum/showthread.php?68844-Questions-Re-ATN-Viper-in-Darkroom/page7

[axs810]

Thanks for sharing that thread! I'll read the whole thing later but it was interesting to see your results with the step wedge. I applaud your patience lol...


I guess just in case I'll play it cautious too and put a piece of silver film with a density of .6 in front of my IR too. Thanks for the tip!

[Ken Lee]

I have changed the title of this thread so that people won't get the wrong idea and jump in with advice without having reading any of the actual discussion.

[axs810]

^__^

[Jim C.]

Good to hear that you've found your light leak, you may want to look into black out curtain material
and doubling that up, local fabric stores may have it, easier to use and will hold up better than plastic
which can be transmissive if the pigments in a run aren't opaque enough or develop pinholes from rough handling.

[newt_on_swings]

The weird thing is the stuff I see just after awakening with eyes wide open. It's like a dream but I 'see' photographic type images that are constantly different. I am not seeing the room contents, but people, as if in posed portraits. I don't know them either.


Sorry to tell you but I think your bedroom is haunted haha. That or it's some type of hallucination from sensory deprivation being in a completely dark and sound insulated room with white noise from a hepa filter.

But yea back on topic. I have and use a pair of the atn vipers with the accessory head mount. I set it up so it's just about pressing onto my eye to limit light spill from the rear. Using a sample filter book pack I cut out a few circles of the darkest nd filter and pressed them in the illuminator to cut off some it light for close up work. Doesn't fog my films while developing by inspection.

[John Berry]

I have used the viper since it first came out. My experience is that I can look at fp-4 from inches away for the whole time ( 15-18 min ). hp-5 needs two layers of toilet paper and look sparingly towards the end. Other films I can't comment on. A look at the sensitivity curve of the film might give you some info on whether you will have a problem or not.

[axs810]

Wow that's a lot longer than I would have expected! Thanks for that info!