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

[Fragomeni]

Hi all. I've always been fascinated with development by inspection and although I've dabbled in it I've spent the majority of my photographic life using very precise time and temperature development practices (Ansel's Zone System) based on extensive testing. I am very curious as to how the darkroom worker who uses development by inspection handles pushing and pulling film. My process involves metering a scene and making a compensation in exposure and then a consequent compensation in development time for N-1 and N+1 exposures. If you are developing by inspection, how would you approach these kinds of situations. Sorry if its a dumb question but since I've really only ever used time and temperature development with constant compensations for N-1 and N+1, I've never had to think about it.

I know many people have different opinion on the usefulness of development by inspection but that’s not what I'm inquiring into. Please leave irrelevant opinions of the technique and other extraneous input out of the conversation. I'm just interested in clarification of how exposure is approached when developing by inspection in practice. Thanks for the help!

[ic-racer]

Irrespective of exposure, I develop for a highlight density that I think will print well. The 'bullseye' is pretty big if you print with multigrade paper.

[Fragomeni]

That was mu thinking, to simply expose for the shadow and develop by inspection for the highlight. My quandry deals with knowing that with my method, I make a slight compensation for the shadow when I have an N-1 or N+1 situation. I know that development has minimal effect on shadow density in most situations but it does still have some effect which is why a slight compensation is built into my exposure and development process which yields spot on negatives.

Anyone else who uses development by inspection have any insight on the subject?

[Mark Sawyer]

You should know your development time regardless of whether you're using an inspection method. The "inspection" should be more for ease-of-handling during processing, not "saving" something radically over- or under-exposed.

[Fragomeni]

You should know your development time regardless of whether you're using an inspection method. The "inspection" should be more for ease-of-handling during processing, not "saving" something radically over- or under-exposed.
Yes, thats a given as far as this convo is concerned. We're not talking about saving anything radically over or under exposed. Just how people who use DBI approach their exposure and development.

[D. Bryant]

Yes, thats a given as far as this convo is concerned. We're not talking about saving anything radically over or under exposed. Just how people who use DBI approach their exposure and development.

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.

[Bill Burk]

Only recently acquired an infrared scope. But not for DBI. I still tray develop by time and temperature and checked by sensitometric test strips.

But the great thing is, if I see a thin negative, I can leave it in the developer after the bell chimes while I move the rest along.

[BetterSense]

It's important to have a standard time, otherwise your visual expectations can 'drift'.

I check my negatives at about 50% of the standard time. Occasionally I find a sheet that I grossly overexposed because I used the wrong film, forgot to stop down the lens, whatever. I can pull those sheets early. I check again at the standard time. If there are some that were underexposed, I might leave them in a bit longer. It's not rocket science and I don't try to make it complicated. I don't even use meters for exposure and I don't do zones.

[Fragomeni]

It's important to have a standard time, otherwise your visual expectations can 'drift'.
I check my negatives at about 50% of the standard time. Occasionally I find a sheet that I grossly overexposed because I used the wrong film, forgot to stop down the lens, whatever. I can pull those sheets early. I check again at the standard time. If there are some that were underexposed, I might leave them in a bit longer. It's not rocket science and I don't try to make it complicated. I don't even use meters for exposure and I don't do zones.
I definitely agree with having a standard time in mind. Having worked with time and temperture for so long, I know what the expected times should be and can use those as the basis of what I'll be doing. I'm interested in using this because so much of my process is so heavily visually based that it feels uncomfortable to work with this segment (development) in such a non-visually based manner. I suppose time and temperature is still very much visually-based and I know someone will make that argument. Yes of course time and temperature is designed to render consistent negatives that will yield the excellent results according to your film tests, and I have indeed experienced this to be true. The caveat for me is not being able to make visual judgements during development itself which is an important concept to me.


Only recently acquired an infrared scope. But not for DBI. I still tray develop by time and temperature and checked by sensitometric test strips.
I'm building a set of IR goggles to be used. Simple construction using welders goggles and high output IR LEDs. There's plenty of discussion on that within this forum so I won't go into here.

[jp]

I'm building a set of IR goggles to be used. Simple construction using welders goggles and high output IR LEDs. There's plenty of discussion on that within this forum so I won't go into here.

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.

[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 (http://www.bhphotovideo.com/c/product/553600-REG/Nyte_Vu_NV60_Digital_Night_Vision_Biocular.html) 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.

[D. Bryant]

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!

Just tape some 4x5 film into the center of your giant holder. I used to split sheets of 4x5 into halves for testing 8x10, very economical.

[Fragomeni]

Hahaha, i think I'll probably just use a 4x5 camera! :D

[John Berry]

I use the ATN viper mono head unit with great results. No fogging with 100 iso but did fog hp-5 unless two layers of crap paper were covering emitter. It may be IR but it CAN be too bright for higher speeds. How close can you focus with the unit you have in mind? I can get as close as 4". You need to be that close to really make a proper judgment call. N, N+, and N- can be developed at the same time, differences in exposure will be obvious and pull times will be done when needed.

[Fragomeni]

The unit focuses to 3' but my plan was to mount a simple close up lens which would allow for close up focus. There is also an attachment/replacement lens that can be purchased for the unit which allows close focus and I suspect I can achieve the same thing using close up lenses and not have to pay an additional $50 but their version.

[R Mann]

On the viper, the lens cap has a "pinhole" that I use to increase the depth of field when working up close. Also, to get a clear image I have to be very careful about aligning the viper with my eye. My guess is that you will have to do some adjusting to get a binocular unit to work - probably the reason they are much more expensive to buy than the mono units. I have used my viper with 400 asa film and have not had a fogging problem, but I use dip and dunk tanks, not tray developing so I am not looking at the film all the time.

[BetterSense]

I taped a reading-glasses lens over my Eyeclops to bring the focus into about 3 feet.

[Jay DeFehr]

You guys are awesome! I'm a real primitive; I just use DBI with ortho film and a red safelight. Everything else is T/t/A.

[Bill Burk]

Dakotah,

Sounds like the real deal, green safelight DBI!

I am often amazed that technology such as IR scopes and densitometers has become so affordable...

On the IR topic there is a thread Re: Questions Re ATN Viper in Darkroom

I did some tests and found measurable fogging. So I knocked down the brightness of my emitter to prevent fogging in normal use.

Here's the test negative:

http://www.beefalobill.com/images/testneg1.jpg

Here's the graph. The IR fogging is the lower-right graph line and the upper-left graph is the normal test strip plot from the sensitometer exposure.

http://www.beefalobill.com/images/testgraph1.jpg

My interpretation of the results:

I will not develop film for an hour, more like 15 minutes.
So I can read down the IR fogging graph line 4 steps (two stops)

That would make my worst case fog 0.21 which is too much.

I would rather have a worst case fog of 0.07

So to step down 4 more steps (two more stops) I glued a piece of black and white negative over the ATN Viper emitter. I picked a scap negative with 0.60 density and used contact cement to glue it to the emitter.

[Ken Lee]

Although the original poster asked that we not get into yet another discussion about IR devices....

I routinely develop between 10 and 20 sheets at a time, and shuffle them in deep containers. During a typical development time of 10 minutes max, they receive between 1/20 to 1/10 of that 10 minutes: somewhere between 30 seconds and 1 minute of exposure. The film is at arm's length, around 30 inches away.

Compared to Bill's more rigorous test of 1 hour duration at 15 inches distance, this is much less exposure. Perhaps that's why I have never detected any fogging.

[D. Bryant]

I mix the chemistry and lay it out with the pre-soak tray first. Above the developer I have two trays - one with water only and the other with developer mixed much stronger than my normal solution.

When I check with the green safelight I can put the neg in the plain water or pop the development from really flat/foggy exposures by a bit in the stronger developer.

Just have some music on and check as it feels right - usually the same basic songs to listen to as I waft the brush over the negative in the tray while developing.

Learned by shooting 6 exposures of the same subject with dark to light, shadow to bright sunlight. Then put them in the developer and pulled one out at half the indicated time, another at 3/4, one at full time, one at 1/4 over, one at 3/4 over and one at twice the indicated time. Then, finished and dried and made contact prints of all 6. The contact prints showed me what was what so much easier than trying to judge the negatives alone.

After that I finessed a bit with a few more test exposures to get confidence. For a short time I shot two of scenes and developed one and then the other with some correction if I thought it needed it. After I got used to it I only shoot one neg unless it is a 'can''t get back/very unusual type of thing.

DBI is simple and easy. Best of all, it works.

What Dakota said.

Paula Chamlee is one of the best practitioners of DBI that I've ever seen. You know that by looking at her work.

But if you want to use IR scopes why not use a Kodak bullet safelight with an IR filter. We used IR scopes and IR safelights 30 plus years ago. Seems to me you are re-inventing the wheel with your project.

[Bill Burk]

Bill's more rigorous test of 1 hour duration at 15 inches distance.

The scope has a dead spot where the reflection off the cover glass burned the phosphors for that hour (I didn't have the sense to cover the lens). I only picked an hour to guarantee a good scale of steps on the Stouffer wedge, and I sure got it.

I keep forgetting that it was close distance aimed straight at the film. Notice the circle of exposure. The beam is highly directional. Real use like Ken's wouldn't lead to measurable fog.

I cannot help but wonder that the human eye really can sense infrared, and the mind presents it as a sensation of slight red. When it's really bright and aimed straight in your eye. It puzzles me that no matter how many sheets of E6 slide I put over it, it still glows just the same color and intensity of deep red.

[Fragomeni]

I definitely think we've turned this into a convo about IR. Oh well, its still informative. Is there a safelight with filter that can block all visible light and produce IR? I'm not familiar with the bullet D. Bryant is talking about.

[D. Bryant]

I learned DBI from Paula and she is very good at it. Also good on answering the questions of those like me who were so certain we would screw up so many things.

I have taught this to a number of photographers and definitely recommend shooting at least 6 identical exposures of a subject with a good brightness range - and doing the development by pulling negs early to late at specific times related to the 'recommended' development. Then be sure to print them. Judging printing quality from negs without printing - especially when testing something new - is foolish. Print and check the prints.

Then, shoot a very flat lit subject(bias the development to longer times) and a very bright and/or high key subject this way, develop and print. This will make your testing easy and hit the main lighting problems you will face.

In each case, make prints to determine what looks best. Might be surprised to find that neg that looked perfect does not make he best print.

I agree completely. Years ago I took Michael and Paula's workshop and using a #10 green safe light for DBI is really easy and cheap. I really don't understand this predilection with IR scopes.

The only reason we used IR scopes was to help find dropped rolls of film in the dark and inspect film splicing machinery in the dark. The scope sat on the shelf almost all the time.

IR light is extremely directional and limited, not to mention that the scope is a PITA to wear and becomes fatiguing.

I would persuade you to forget the IR scope as it's a total distraction to your goal.

As Dakoda said, Paula showed us beautiful prints made from way less than perfect negatives. It ain't rocket science and it shouldn't be. Always make prints from each negative. Simply looking at the neg. doesn't tell the whole story.

[Jay DeFehr]

I use DBI under very limited circumstances, mostly for ortho film, where I don't need to worry about fogging my film with the inspection light, but also, occasionally for pan films, but only under unusual circumstances, such as I don't remember what is on the film, or I'm using some unknown developer, etc., and I never develop more than one sheet of pan film at a time by inspection. I also don't like to develop small sheets by inspection, both because it's more challenging to see the details well, and because I prefer to develop smaller sheets in batches. DBI can be useful, and it's not particularly difficult to master, but for me, it's a very limited method.

[Fragomeni]

Update:
The Nyte Vu IR goggles I ordered from B&H arrived a today. I've been able to go over them thoroughly and have nearly completed making them darkroom ready. Some important things to note with this set of goggles is that all of the reviews about the weak spring and how flimsy the plastic is that holds the goggles in the up position (so you can see normally without having to remove the goggles) is absolutely true. Trying to flip them to the up position is pretty much useless but in reality this is irrelevant to our purposes. When worn, the goggles are not held tight against the face and the eye cups (removable) are not pressed against the face. This means that there is the possibility of light spill from the LCD displays reflecting off your face and fogging film. I suspected this from the start and was prepared to combat this as well as the flimsiness of the design. My solution to all of this, which worked perfectly, was to take a pair of welders goggles (the kind with one large rectangular window, not the round windows for each eye), remove the whole frame that holds the filter in the goggles, and fix the IR goggles to the welders goggles from the outside. The Nyte Vu's viewing area fits quite well into the hole left when the welding goggle's filter frame is removed and a good supply of gaffers tape holds everything in place. the elastic strap on the welder's goggles holds everything snug against the face and keeps all light from the LCD screens trapped inside the goggles to prevent and light spill/reflection and fogging. The original head brace and strap provide extra support and stability for the unit when in use. It is important to note that this is quite comfortable to wear (although the real test will be after several hours in the darkroom).
The IR LEDs do produce a noticeable red glow although not as bad as the 850nm IR LEDs I'd tested before. My next step is to stack several layers Rosco Congo Blue filter to block any visible red light from the IR LEDs. A contributor in another thread related to this topic was kind enough to let me know that Rosco and Lee filter material is completely transparent to IR light. A few layers of the Congo Blue should block all or most of the visible red glow and allow all or most of the IR light to pass through. Once this is done the goggles should be ready to use for development by inspection without risk of fogging film.
Lastly, I think it is important to note how clear and crisp these goggles are. I was shocked by the image they produce. These are different from most military night vision in that they use an extremely low light sensitive camera which transmits an image onto two LCD screens in the goggles. Most military goggles use light sensitive cells to amplify light. The Nyte Vu goggles are produce a black and white image not a green image. I compared these to a set of very high end military spec night vision goggles (well out of my price range) and I definitely prefer the B&W image to the green image. The Nyte Vu goggles focus by rotating the taking lens. Focus is SHARP and I have no concerns about being able to make out details in the film. Also, I thought these goggles had a close focus max of 3 feet and was prepared to figure out a way to get closer focus or buy the close focus lens but I was pleasantly surprised to find that they focus down to under a foot! I think its around 6-8 inches! This was the biggest shock of the day and a welcome one.

With a few simple mods these goggles are already far surpassing what I was expecting. I'll update further once I have the filters in place and test it with film. I am so excited about these goggles!

[Fragomeni]

Did a few experiments since the goggles arrived. I layered a substantial amount of Rosco Congo Blue filter material in front of the IR LEDs. I was able to cut the glow by about half but beyond that blocked too much of the IR light's range. I have a few 940nm IR LEDs sitting around so I blocked the built in IR LEDs entirely and tested to see how much illumination the goggles would pick up from the 940nm IR LED. It was bright and worked very well. The 940nm IR LED illuminated a substantial area and the image quality didn't seem any different. I don't know why these goggles aren't just made with the 940nm IR LEDs instead of the 850nm IR LEDs. The 940nm IR LEDs have virtually no visible red glow and I would be much more comfortable using them then the built in 850nm IR LEDs. I'm going to talk to a few friends tomorrow to see if any of them can switch out the 850s for 940s for me. I've seen accounts of people doing this with these goggles and from what I understand it isn't difficult.

[Fragomeni]

Update:

I successfully switched out the 850nm IR LEDs for 940nm IR LEDs! The job was simply and took about an hour. The 940nm IR LEDs work perfectly and produce almost no visible red light, certainly not enough to fog film during development. Visibility through the goggles seems unaffected by the change. It kind of boggles my mind that these goggles aren't made stock with 940nm IR LEDs. Anyway, it works perfectly and I'll probably start developing film with them this week. Just wanted to update in case anyone was interested. Take care and thanks to everyone for the help.

[MMELVIS]

Update:

... Just wanted to update in case anyone was interested. Take care and thanks to everyone for the help.

Look forward to your ongoing tests