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ckpj99
1-Dec-2012, 14:28
Hey folks,

Do you any of do any actual testing of your darkroom's darkness? Like leaving film or paper out for a long period of time or some other test.

Just curious.

Ironage
1-Dec-2012, 14:30
I would but the light leaks are too obvious! I just work fast;)

vinny
1-Dec-2012, 14:34
my darkmeter goes to 11 in mine. that's dark enough.
if you can't see your hand, it's pretty dark

ckpj99
1-Dec-2012, 14:39
To my eyes, my darkroom is completely blacked out. That being said, I'm going to tray develop some 4x5 film this week, and I'd rather not screw it up.

Heroique
1-Dec-2012, 14:51
Normally, I would trust my dark-adjusted eyes after a few minutes, but the monsters and phantoms I start seeing affect my judgment. :(

lenser
1-Dec-2012, 15:03
I wouldn't exactly trust my eyes based on the simple situation that when I go to bed, it is total darkness in the room, but if I get up for a bathroom break a few hours later, I can see everything I need to find my way around without any light source except the night sky outside the window. The cones and rods apparently pick up lots of night light after that rest period. Film and paper don't have that lag time, so what your eyes don't see may still be plenty of light to fog film or prints. Do the test!

wallrat
1-Dec-2012, 16:36
If you are concerned about film or paper fogging, you can do a very simple test. Leave fim or paper out in you darkroom for the longest possible time you would be working with it, then maybe double that time for good measure. When you have reached that point develop the test piece along with a sheet that has been in a protective box or paper safe in the same developer, same time, agitation, etc. Compare the results.

Dan Henderson
1-Dec-2012, 16:37
I recently changed from daylight tank to open tray development. After 10 minutes in the "dark" I was surprised by the amount of light leaking in. So off to Lowe's I went to buy several tubes of black caulk and foam door insulation, which, along with some torn chunks of black foam pipe insulation, has eliminated probably 95% of the infiltration.

I am still somewhat concerned about tray development of infrared film with the very small amount of light leakage remaining, along with a few bits of luminescent tape. I am wondering how dark is dark enough for IR film?

ckpj99
1-Dec-2012, 16:54
I've sat in the complete dark in my room for over 10 minutes. I can't see anything. I think I'm just going to load my film in a dark bag, and then try the tray developing. That should eliminate one variable. If the film looks good after that, I'll try loading my carriers in the room.

Bill Burk
1-Dec-2012, 19:26
I'd leave a piece of 400 speed film for an hour in the darkroom with a step wedge over it under glass.

Using this test with my IR scope aimed directly at the film, I came to the conclusion that I could work for 15 minutes with the scope on with no measurable effect.

You could quantify how dark your darkroom is the same way.

Leonard Metcalf
1-Dec-2012, 21:18
I've sat in the complete dark in my room for over 10 minutes. I can't see anything. I think I'm just going to load my film in a dark bag, and then try the tray developing. That should eliminate one variable. If the film looks good after that, I'll try loading my carriers in the room.

Well... that is the test I have been using for years... ten minutes and you can't see any light leaks, when you look around, and you have a room good enough for me..

photobymike
1-Dec-2012, 23:12
Something that a lot of photographers overlook is the florescent lights. Long ago i was having a problem with fogged film in my darkroom. I sat in the dark for 30 or 40 minutes waiting for eyes to adjust.... Zazam my lights were glowing and occasionally flashed .. it was dim but it was happening. I had to remove the florescent lights and go with incandescent lighting. all was fixed.....

Arne Croell
2-Dec-2012, 00:17
Something that a lot of photographers overlook is the florescent lights. Long ago i was having a problem with fogged film in my darkroom. I sat in the dark for 30 or 40 minutes waiting for eyes to adjust.... Zazam my lights were glowing and occasionally flashed .. it was dim but it was happening. I had to remove the florescent lights and go with incandescent lighting. all was fixed.....

True, fluorescents can be a problem that way. It depends a lot on the phosphor being used. In my experience, cool white tubes tend to be more of a problem with phosphorescence than warm white ones, but it might also depend on the manufacturer. In any case, spending 15-30 minutes in the dark to let the eyes adapt should show any light leaks. Fully dark-adapted eyes (about 30min) are quite sensitive to light.

Doremus Scudder
2-Dec-2012, 04:37
Your eyes are very sensitive AFTER they have become dark adjusted (as Lenser observes in his post above). It takes about 30 minutes to reach full adjustment, but most of it happens in the first 5-10 minutes. After your eyes are dark adjusted, they are sensitive enough to detect just a few photons at a time. http://en.wikipedia.org/wiki/Night_vision

So, test your darkness with dark adjusted eyes. First look around for light leaks; under doors, around windows, cracks in the wall, seams between beams, etc. Crawl around, stand on chairs, change your head height and points of view. Do a few 360 turns from different positions. Identify and block whatever leaks you find.

Next, try to put your point of view where the light sensitive material is going to be, e.g., in the tray positions, loading table, etc. and look for more leaks. If this is impractical (i.e., requires too much limbo dancing) place a sheet of white paper in those critical positions and check for reflections.

If you see nothing, it's safe for film and paper.

Do a safelight test for your paper; it's easy and will give you peace of mind. I like knowing that my fairly bright darkroom is safe for more than 20 minutes for my enlarging papers.

Oh yeah, ditch the flourescents or make doubly sure they don't glow after a few minutes. Also, mark light switches, etc. so you don't accidentally switch on the white light when you don't want it. I've ruined more things that way than with light leaks...

That's all there is to it.

Best,

Doremus

BetterSense
2-Dec-2012, 08:46
I can actually see light leaks in my darkroom, but it's never been a problem. I also have 2 gralab timers and some glow-in-the-dark sticky stars in there, so I can often see my hands or what I'm doing *by silhouette* only. After being in there for a very long time, such as when rolling 35mm bulk film, I can start to see white things by reflection, barely. I'm not fixing it though, because it hasn't been a problem. If you think about it, if I wanted to take a picture in there at f/2, how long would I have to have the shutter locked open? I'm not sure if even several hours would result in density on the film, and film with no lens approximates f/1.

ic-racer
2-Dec-2012, 08:47
Hey folks,

Do you any of do any actual testing of your darkroom's darkness? Like leaving film or paper out for a long period of time or some other test.

Just curious.

The test for light leaks occurs at the same time as you do the safelight test.

In terms of testing for total darkness and ability to manipulate unexposed film, you can just use your eyes for that one. Your eyes are more sensitive than the film.

BetterSense
2-Dec-2012, 08:58
I totally agree that your eyes are more sensitive than the film...unless it's IR film, or unless there is UV in your darkroom from fluorescent light, or unless your film is orthochromatic and the light source is red. But other than that.

Also, there is a Kodak tech publication about safelight testing. I highly suggest following their procedure, because it is much better than the simple 'leave a piece of film/paper sitting out' test, and it's not any harder to do.

Steve Smith
2-Dec-2012, 09:06
Mine's not completely lightproof but it's dark enough for making prints. I think I would have to improve it a bit for handling film in though. At the moment I use a changing bag.


Steve.

jon.oman
2-Dec-2012, 09:31
I built a new darkroom this last fall / spring. There is only one opening to the outside of the darkroom, the door. My darkroom is an 8 by 16 foot room at the back of my 16 by 24 foot shed. The shed has a roof vent on the ridge, and two flat vents at each end. When I close the shed door, and arrange the 'commando' cloth curtain in front of the darkroom door, it provides enough light proofing. I used drywall for all internal walls and the ceiling. I can sit in the darkroom on a bright South Carolina day for an hour, and not see a single light leak. I think I'm safe....

Kevin Crisp
2-Dec-2012, 10:16
If you sit in the darkroom for 10 minutes with the lights out and your eyes open and you can't see any light leaking in you are fine.

Brian Ellis
2-Dec-2012, 11:55
If you are concerned about film or paper fogging, you can do a very simple test. Leave fim or paper out in you darkroom for the longest possible time you would be working with it, then maybe double that time for good measure. When you have reached that point develop the test piece along with a sheet that has been in a protective box or paper safe in the same developer, same time, agitation, etc. Compare the results.

For paper that actually isn't a real good way to do a proper test since it doesn't take into account the light that strikes the paper during the time it's being exposed in the enlarger or contact printing frame.

There's a lot of information available in many different places that explains how to do a proper safelight test for paper. Ansel Adams' book "The Print" on page 32 is one good source, I'm sure there must be others on line. But any method should involve exposing the paper under the enlarger for a certain period of time (Adams suggests an exposure sufficient to turn the paper a very light gray) so that you're taking that light into account as well as the light from the safelight.

ataim
2-Dec-2012, 12:31
my darkmeter goes to 11 in mine. that's dark enough.
if you can't see your hand, it's pretty dark

Why doesn't your darkmeter just stop at 10.

These go to 11, its one darker:)

C. D. Keth
2-Dec-2012, 12:35
Well... that is the test I have been using for years... ten minutes and you can't see any light leaks, when you look around, and you have a room good enough for me..

I don't think I've ever been in a darkroom that didn't have a few small leaks visible after 10 or 15 minutes and it's always been fine.

Bill Burk
2-Dec-2012, 18:32
If you think about it, if I wanted to take a picture in there at f/2, how long would I have to have the shutter locked open? I'm not sure if even several hours would result in density on the film.

This is my favorite measure of darkroom darkness.

Then there is the story of the guy who turned on his light for 1/10th of a second with the film out... got some pictures but man, it fogged worse than I thought it would.

Darin Boville
2-Dec-2012, 20:47
I'e had a number of darkrooms over the years and I've always been astonished at how much light can leak into a darkroom yet not expose the film. There's a big difference in being able to see light under the door or whatever and that light causing a problem. As for testing, if you load/unload film in the dark you test all the time. Can you see you hands (not their silhouette but the hands themselves) when the film is done being loaded/unloaded? That's not good. Better safe than sorry.

However, I have been burned several times by inadequate safelight testing. Once i spent a lot of time looking at other variables (for slightly dead highlights) before it finally dawned on me that it was the safelight. The white would go from white to slightly too dark--couldn't hit the tone in the middle, as I recall. Don't forget to put the paper in the brightest spot it would be in for your tests. No good giving four times ambient darkroom exposure at the easel when the safelight is over the sink--might not have a problem until you start extending development times. Then the mystery will begin.

--Darin

ckpj99
2-Dec-2012, 20:58
By reading some of these comments (and by some film work I did today), I guess my darkroom is the best one ever. When i finished the room up a few weeks ago, I patched every spot of light I could see with black tape. My door is "sealed" using multiple layers of black flannel, and I use a length of black flannel to block the bottom of the door.

I was in there for over an hour today. close to 30 minutes of that in complete darkness with no safelight. I didn't see a single pin point of light. You guys talk about seeing your hand. When the safelight is out, I can't see anything. There could be a wild raccoon perched on my enlarger, and I would have clue.

altoyes
16-Jul-2016, 07:22
hi folks
would holding up a white piece of paper work? ie if i cannot see the paper, does that mean it is light-proof?

Bill Burk
16-Jul-2016, 07:36
altoyes,

How about this test? Do you have a GraLab timer or similar with "glow in the dark" dial? A wristwatch would do.

You know how sometimes those dials are "super-charged" and bright and other times they are "rather dim"... Don't supercharge the dial. Let it get dim.

Sit in the dark and wait until your eyes accommodate and the glow in the dark dial is easy to see.

Now, if that dial is the brightest light observable in the darkroom, you probably have a safe environment for working.

Jac@stafford.net
16-Jul-2016, 07:37
hi folks
would holding up a white piece of paper work? ie if i cannot see the paper, does that mean it is light-proof?

Not necessarily. It takes a long time for our eyes to adapt to perfect darkness.

A special 'gotcha' occurs when there is a tiny light leak that streams into the room, but you don't see it. Then when you most need darkness, you load sheet film right in the path of that leak. :( Don't ask how I know.

Tin Can
16-Jul-2016, 07:41
My darkroom is dark and I chase every bit of light and kill it.

However I can still see my hands flopping around, so I 'looked' deeper.

Seems some of us can see our hands from muscle/mind memory.

http://www.npr.org/sections/health-shots/2013/10/30/241906619/seeing-in-the-pitch-dark-is-all-in-your-head

Jac@stafford.net
16-Jul-2016, 07:47
My darkroom is dark and I chase every bit of light and kill it.

However I can still see my hands flopping around, so I 'looked' deeper.

Seems some of us can see our hands from muscle/mind memory.

True! It's freaky when we first realize it. I see the film and holder or reel, although I learned later in life (after hand injuries) that it was not really accurate. I know because I would see a finger and thumb wiggle that are no longer mobile. Bummer.

Jmarmck
16-Jul-2016, 07:50
Go spend a few hours in a cave or mine. That is dark. After a period of time your brain goes into depravation mode. Your eyes will be so starved for input that you will start seeing sparks of light that are not there. If you have a light source you will see it as your brain will latch on to anything it can get. It may even appear to move or float disorientating you just a bit. Is the film more sensitive than you eyes? Not sure. I would imaging that depends on the film. But when the light levels are that low I don't think it matters. If you can sit in the room and not see anything after 15 minutes I would say you are good to go............turn the lights on first so you don't trip over the cat.

denverjims
17-Jul-2016, 14:51
Something that a lot of photographers overlook is the florescent lights. Long ago i was having a problem with fogged film in my darkroom. I sat in the dark for 30 or 40 minutes waiting for eyes to adjust.... Zazam my lights were glowing and occasionally flashed .. it was dim but it was happening. I had to remove the florescent lights and go with incandescent lighting. all was fixed.....

Back when he did/entered this [2012] don't think they were available, but now you can buy (at least in US) LED direct replacements for fluorescent tubes. Some require simple wiring change to fixture but others do not. No afterglow. Saves changing fixture; little heat generated; and saves energy over incandescent.

Worked well for me, Jim

Tin Can
17-Jul-2016, 15:11
True! It's freaky when we first realize it. I see the film and holder or reel, although I learned later in life (after hand injuries) that it was not really accurate. I know because I would see a finger and thumb wiggle that are no longer mobile. Bummer.

Actually if you the read link, it's synesthesia and I bet common among people who work with their hands, especially like me who often installed things where I could not see the thing, the place or my hands. May as well been blind. If fact I would shut my eyes.

Losing digits is tough, we had a lot of that at 'ye olde punch press factory'. I was on Medical/Fire/Hazmat team I won't describe what I have seen and worked on. My older brother lost 2 toes as a child, it still hurts real bad. I can still here him screaming.

Tin Can
17-Jul-2016, 15:13
Go spend a few hours in a cave or mine. That is dark. After a period of time your brain goes into depravation mode. Your eyes will be so starved for input that you will start seeing sparks of light that are not there. If you have a light source you will see it as your brain will latch on to anything it can get. It may even appear to move or float disorientating you just a bit. Is the film more sensitive than you eyes? Not sure. I would imaging that depends on the film. But when the light levels are that low I don't think it matters. If you can sit in the room and not see anything after 15 minutes I would say you are good to go............turn the lights on first so you don't trip over the cat.

Since my entire loft is Full Dark and I also sleep there, it is amazing what one sees...

altoyes
17-Jul-2016, 21:24
thank you all so much.
i really love all your replies, keep going ....

152989
152990

barnacle
23-Jul-2016, 13:00
Don't make the innocent mistake my father did; he chanced to keep a small chunk of what turned out to be pitchblende as a paperweight on top of a box of printing paper...

Neil

Jac@stafford.net
23-Jul-2016, 13:15
Since my entire loft is Full Dark and I also sleep there, it is amazing what one sees...

So true. I had the same kind of sleeping loft. One night I envisioned my late wife there. Since then I had a permanent night light.
.

Tin Can
23-Jul-2016, 14:38
So true. I had the same kind of sleeping loft. One night I envisioned my late wife there. Since then I had a permanent night light.
.

I saw something very different from my 2 late wives.

I am very careful to not watch horror movies.

I have no ideal where the odd images come from, not TV and movies.

I am starting to believe in primal memory. As in dinosaur/dragon recall from DNA imprint and Jungian Archetypes.

We are very strange DNA bags.

Willie
23-Jul-2016, 20:12
By reading some of these comments (and by some film work I did today), I guess my darkroom is the best one ever. When i finished the room up a few weeks ago, I patched every spot of light I could see with black tape. My door is "sealed" using multiple layers of black flannel, and I use a length of black flannel to block the bottom of the door.

I was in there for over an hour today. close to 30 minutes of that in complete darkness with no safelight. I didn't see a single pin point of light. You guys talk about seeing your hand. When the safelight is out, I can't see anything. There could be a wild raccoon perched on my enlarger, and I would have clue.

Flannel will eventually end up with dust problems. Might try some black plastic sheeting. A couple advantages. One is that it attracts the airborne dust. The other is that you can wipe it down with a damp cloth to clean it.
If you rub it with a woolen cloth you generate some static electricity and that helps in attracting the airborne dust.
A good HEPA filter run in the darkroom for a half hour or so before you start a work session really helps keep the dust down.

Jac@stafford.net
23-Jul-2016, 20:46
I was in there for over an hour today. close to 30 minutes of that in complete darkness with no safelight. I didn't see a single pin point of light. [...] There could be a wild raccoon perched on my enlarger, and I would have clue.

Or worse, this on your enlarger (http://www.digoliardi.net/girl-sitting-on-enlarger.jpg). Talk about a 3D effect print!

Tin Can
23-Jul-2016, 20:54
T o be clear, the only thing I 'see' is my hands when I wave them in front of me.

I don't see my hands 2 seconds later loading holders and hangers. I don't see the white toilet, or the silver vent pipes.

The mind not the 'eyes' see the waving hands.

It's been proven, but nobody read all the posts, or checks links when provided.

Now how do I completely black out a Ram Promaster which may be my next darkroom.

whitemary
24-Jul-2016, 18:26
I just work fast
http://hautavis.net/146/o.png

Taija71A
30-Jul-2016, 12:18
... Seems some of us can see our hands from muscle/mind memory...
Not really...

As per the Article: http://www.npr.org/sections/health-shots/2013/10/30/241906619/seeing-in-the-pitch-dark-is-all-in-your-head

"Of course, these folks didn't really have night vision. None of them could see someone else moving in the dark. In reality, the participants' brains were fooling the eyes into thinking they could see, filling in the visuals based on past experience and memory."