A 101 Guide To Digital Restoration Of Analog Silver Halide Emulsion Photography

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It is my pleasure to start this thread for our mutual enjoyment - read on, and participate at your own pace and leisure:- :grouphug:

Nearly all of us have a collection of old photographs gathering dust somewhere, and not all together entirely sure what to do with them.

One thing to be really sure about, is not to throw them away - please, do not do it, as all photographs have an inherent value. I will repeat this. All photographs made from analog silver halide emulsion technology are of incalculable value, and are to be treasured - hopefully forever, and if they are digitised, this will happen.

Each and every photograph ever made using film is a unique record of a moment in time made from light bouncing off a reflective surface, travelling through the air, passing through an optical lens which by way of its design, then projects a visual image that becomes embedded within a layer of gelatine impregnated with light sensitive salts of silver. When this self-described piece of 'film' is chemically developed, halides of silver migrate into molecular clumps that wrap themselves around the photographic image as a three dimensional matrix known as 'grain'.

For the sake of clarity within this initial treatise, we shall accept that all analog photographs are made up entirely of overlapping grains of molecular silver, giving each and every photograph its own unique and individual visual character - quite unlike digital capture, were everything looks more or less the same - usually deathly dull, and not entirely convincing. But more about that irksome paradox some other time ....

When you pick up and look at one of your (many thousands!) of photographs, there are two things that actually happen. The moment recorded as light entwined within the photograph travels forward in time to meet your eye, and your eye travels back in time to look into its descriptive likeness. The gap between the two events widens at a constant rate of time, which can be considered as a conceptual essence of time travel itself.

The 20th century's main form of visual documentation is analog photography, and as such, is incontrovertible proof of a remarkable age that truly existed, and now gone forever. All the light that ever shone in the collections of photographs that we have in our possession, is still travelling from the past into our present, and onto, and into our children's future. This is why I say all photographs, no matter what they are of, or what they depict, are of immense, incalculable value.

Only there is a major hitch. As we look into a photograph, something else happens. The viewer and photograph become older and older, and eventually both will finally perish to become dust. The solution to this dilemma is to permanently digitise the photograph, so as to enable its encaptured light to continue its journey through time - indefinitely.

I will write, and continue to write, until I have explained everything there is to know about the digital preservation and restoration of photographs, with an emphasis upon pictures of family and loved ones.

If you can (and do!) understand audio, then you will definitely be able to master the intricacies of how to successfully scan photographs, negatives and transparencies with consummate ease and confidence. Without knowing it, most of us are already halfway there.

I will, for the sake of clarity, make constant analogous references to audio. For what is light, but sound at a higher frequency?

Anyway, one thing, one day at a time......... :yes:

ToS
 
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It is interesting timing as I was looking last week at some slides that I had scanned perhaps 15 years ago, and was never particularly happy with the results. However I discovered that (ironically) the Nikon software that I use with my DSLR does a very good job of bringing up the contrast in the scans. Scans that I just felt I couldn't get the true dynamic range of the slides, are definitely closer, though perhaps still not as good as if projected.

Attached is a scan from that film. Taken I think in 2003. It is of the Heads of the Nambucca River, in Nambucca Heads. I used to go fishing on that river with my grandfather every weekend. He passed away about a year after we moved away (in 1982). I think it's Fuji Provia 100F. This is a resized version of the original 4000dpi scan. Scanner a Canoscan FS4000, software Vuescan.

edit: and the second is the first photograph I ever took. Christmas Day 1975 with my just unwrapped Kodak Instamatic. I don't remember how I scanned that one because the negatives don't fit in my film scanner, must have been on the long defunct flatbed...

Tony.
 

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Interesting timing.

I have about 500 35mm slides I am wanting to digitize to give copies to my siblings.

I looked at commercial processing and may eventually go that route, however for the time being I have my projector, screen and slides setting in the den and was considering (1) video taping so I could give a narration, or (2) Use my EOS Rebel to capture each one.

Or, I could purchase a dedicated scanner for the slides.
 
I've had 4 slide scanners. Problem was that I did medium and large format slides. I would recommend the V850 Pro.

Don't buy the Powerslide 5000 -- it jams so frequently as to be useless.

I've had a Nikon CoolScan, Minolta Dimage, and an Epson 1640. All boatanchors now.

For only 500 35mm slides, I would send them out to Fotobridge.
 
Actually, I am using an old Coolscan III I purchased non working for $5, it just needed the dried out lubricant replaced and I dusted off the mirror at the same time.
OK, It only works with a Win98 machine and needs an SCSI cable but 6 Meg produces good enough resolution for a computer or TV screen.
My Nikon DSLR with 24 meg is dialed back to 6 meg and I got some images produced on a large vinyl printer and they look great, JPEG compression does the magic.
 
When this self-described piece of 'film' is chemically developed, halides of silver migrate into molecular clumps that wrap themselves around the photographic image as a three dimensional matrix known as 'grain'.


Only there is a major hitch. As we look into a photograph, something else happens. The viewer and photograph become older and older, and eventually both will finally perish to become dust. The solution to this dilemma is to permanently digitise the photograph, so as to enable its encaptured light to continue its journey through time - indefinitely.


ToS

Thanks for starting this, as many in the DYI audio group will appreciate it as well. I am so glad you recommend not throwing old photos away, and bring up the magic that traditional photographs may have.

I have photographic experience dating to the 1960's, and I still use film today. One small quibble is that the halide crystals, or "grain", does not migrate when it is developed. Also, what dominates a printed image as "grain" is what is between the grains on the film, not the grains themselves.

If stored properly, film and prints, especially black & white, will last centuries. Digital versions can conceivably last this long, if hardware and software are maintained through the ages, but this is not easy or cheap, and of course no one has done it yet. The Hollywood film industry has realized this (e.g., see "The Digital Dilemma" I and II, published by the Science and Technology Council of the Academy of Motion Picture Arts and Sciences).

Currently, I have a research project that involves archiving old and new images taken on film. Although the film and prints are being scanned to allow easy sharing, the film and silver gelatin prints are the long-term storage elements in the archive. Recently, I have printed film dating to the 1880's, and they still look good.

A CD or thumb drive in an attic will probably not have much value after 50 years, but there are plenty of shoe boxes full of photos that are still usable. I have worked with many negatives that are 50+ years old, some stored in shoe boxes in an attic, and they look as good as new and print well using traditional analogue printing methods.

My main point is that a digital copy is not a perfect substitute for a silver-based image. The digital files will need a lot of maintenance, and as of today, no scanner can capture all of the detail on film or print (silver halide crystals are typically about 1 micron across), and scanner resolution is about 10x too coarse to resolve them, although on a practical level, a good scan is usually good enough.
 
Let's Start With A New Print Box And Some Cotton Gloves

Real nice - this thread has only been running 24 hours and already lots of posts. :)

Due to constraints upon my time, it may not be always possible for me to answer every question, but I shall be reading everyone's posts for use as reference points in writing what will be a series of articles that shall evolve as the thread moves forward. Every article will have a title, and every reference to a quote or a pictorial attachment will include the member's post number. In this way the thread will have some coherence as a future hands-on resource.

Let's start with an imaginary long forgotten box of family photographs, found in a old cupboard, and has obviously been left alone for long enough to need some serious loving care and attention. It's a cheap and nasty brown corrugated cardboard box that's seen some damp, and is a bit chewed around the edges by mice.

Let's open the box - smells a bit kind of musty and chemically. This is because a cardboard box is made of materials that over time will decompose and release the kind of noxious gases that will affect the colour and chemical stability of transparencies, negatives and prints.

So, what you need is an archival quality replacement print box made from thick card impregnated with calcium carbonate that has a buffered pH value. Not too acidic or alkaline, and when photographic materials are placed inside, they will immediately become chemically stable and stop deteriorating any further.

Although the cardboard box seems to have been chewed a bit, there are thankfully no entrance holes large enough for mice or insects. Miraculously, the damp hasn't penetrated the box either, and that means no mould. A box of negatives left in a damp basement will be irreparably ruined by mould within a month. Mould is certain death to all silver gelatine based photographic materials. Mould is not your friend.

Thankfully, all the prints, negs, and prints are in their original bags, boxes or envelopes - leave them exactly as they are for now. Do not mix them up, they tell their own story exactly as you found them. You need to get yourself some lint free cotton gloves for handling photographic materials. Fingerprints are acidic and attract mould. To stop the growth of mould, get some sachets of silica gel. This is a commonly available desiccant that will lower the box's internal humidity. Mould can only grow when it is damp and has something to eat.

So using cotton gloves, carefully pick out all the photographic materials and place them in the archival print box, along with a nice big sachet of silica gel. Then put the new box into a strong mouse proof plastic storage container with a lid, and place the container back in the cupboard, where it is now cool, dark, and dry and chemically stable. This treatment alone will increase the lifespan of your photographs tenfold.

Next, we figure out what to do with what we've got. :eek:

ToS
 
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Nice. If you have any tips on "safely cleaning" negatives that would be great. I have one strip that after scanning I was dissapointed and carelessly left sitting out and they became contaminated (not sure by what, but not mould). I later realized that I liked the photos but I couldn't get a decent scan so back in the box they went... I've never known how I could safely clean them.

Tony.
 
I have photographic experience dating to the 1960's, and I still use film today. One small quibble is that the halide crystals, or "grain", does not migrate when it is developed. Also, what dominates a printed image as "grain" is what is between the grains on the film, not the grains themselves.

agreed.

i have Life, Time and Look mags from the 1950's and 1960's -- some French mags of the same era -- what is disappointing is that the dyes migrated over a period of years. While the colors remain true, the images are not nearly as sharp as they were in my youth.

C-prints should last -- but I haven't done a C-print in over 20 years. (Used to get the chemistry at B&H)

Oh, a post script -- I found a reel of 8mm film after my uncle passed away -- took it to my camera shop and had it digitized -- it was the record of my Mom's first communion back in 1931! I don't think it had ever been viewed as the Depression was heading into its worst and no one was buying projection equipment.
 
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I think it is cellulose based, not acetate.

i think you mean "cellulose based, not polyester..."

cellulose films kind of "melt"

cellulose nitrate film stock can combust spontaneously -- production of these films stopped in the late 1940's


here's a bit of trivia -- Eastman's cellulosic photo stock business gave birth to their acetate "tow" business -- essentially cigarette filters. In the 1990's this was the most profitable part of the company. (Eastman itself was spun out of Kodak in 1994)
 
I just looked up photo-flo (have never done any of my own developing)

I used it in my home darkroom, and to install window tinting film, but I just assumed that it since it was a Kodak product, it went the way of Kodachrome.....Momma took it away.

Google tells me otherwise. I was really surprised to find that you can still buy D76, Diafine and Tri-X! Now if I only had a film camera....
 
i think you mean "cellulose based, not polyester..."

cellulose films kind of "melt"

cellulose nitrate film stock can combust spontaneously -- production of these films stopped in the late 1940's


here's a bit of trivia -- Eastman's cellulosic photo stock business gave birth to their acetate "tow" business -- essentially cigarette filters. In the 1990's this was the most profitable part of the company. (Eastman itself was spun out of Kodak in 1994)
Ehm, I mean cellulose acetate, not cellulose nitrate (and not polyester either). Brittle after 50 years of ignorant storage.

Also in the past our family did not care much about negatives, we just put the prints in albums to show them. Ironically, albums are long lost along with prints, but I found some B/W negatives, color negatives and even framed slides.

Digitizing photos is just a convenient way to handle them for short to medium term. For archiving there is no better medium than those films/prints themselves in their original form.
 
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