Acid Burns

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hawaii photog

Grumbler in Training
Joined
Feb 15, 2004
Posts
7
Loc
Wahiawa, HI
Hi guys,
I'm new to the site and was refered by a framer to get some info. I have been plagued by clients coming back to me with bronzing happening throughout the photograph. It seems to start as either bronze or silver spots and spreads through the darker shadows first. It looks bad and when I showed it to a printer he said it was acid burn from the mat. Is acid burn a metallic color? I would appreciate all the info I can get . This is driving me crazy.
thanks!
 
Can you give us more detail? Are these colored photos, b & w, old photos, copies of old photos, how long they were under the mat, etc. The only experience I had with something like this was a customer had a copy made of an old photo and the new one was a black and white on todays photo paper(type escapes me at the moment) instead of rag papers. I'll see if I can find the article which was in PFM sometime in the last 2 years.
 
sorry, they are black and white on RC papers. The prints range from 5 years to 2 years old. They are coming from all types of frames, not just from professional framers. I hope this helps.
 
hawaii ;while Jpete's questions about the Photos are important,the type of mats is even MORE important.
Some different mats can react differently with different types of photoprocessing.So whi;le we now knw they were B&w on RC paper and they are 5-12 years old,can you tell us what the mat amd mounting materials were ? as Picky as this sounds it can make a ifference in what you are seeing.While I have very limited knowledge of Photos many here can give you a lot of information once yo supply all the FACTS.
BUDDY
 
I don't think it's from the mats. Even the worst matboard manufactured in the time period you're talking about is bufered and "acid-free". It would also be unusual for a mat to affect the image areas that are not in contact with the mat.

I've seen something similar to what you're describing from inadequately washed fiber-based prints, but that would be very unusual for an RC print.

Still, I would look at the lab rather than the framing in this case.
 
Sorry to omit this info but because these are clients coming back to me about thier photos and I don't know anything about how they are framing them, they could be in all kinds of frames. I would guess that some were cheap with just a cardboard back while others were bought like at Macy's. I did not think to ask about the framing because all along I thought it was a printing issue. Could this range of framing cause this problem. Would even the cheapest of frames -non acid free, do this kind of damage?
 
I've seen this happen too. I don't know what causes it, but I suspect that it has something to do with the fact that the prints are dye based rather silver gelatin.

Because only the black dye is developed perhaps flaws in the processing, which would otherwise be masked or compensated for by the other color dyes, show through. It may be that it is asking too much of color printing paper to be used for monochromatic images.

Rebecca
 
Rebecca,
thanks for your info but these are true black and whites photos. I am sure they are silver based and that's where the problem might lie. They are not done on fiber but on Resin Coated paper. They are hand processed at a black and white lab. The labs are telling me that the acids from the frames leak out over time and react to the photgraphs under glass. They said it was an acidic environment that caused it, but it sure seems like a lot of damage. I figure, you are the guys to ask because if you all have seen this, i'll know my lab was right. If not, then maybe it is a printing problem and I have to investigate that side more.
 
If you can, examine the backing substrate. If that has a stain, then the problem stems from the materials.

But resin coated papers (being basically a plastic material) are all but impervious to chemicals in the short run.

Without seeing the actual framing package, I would be willing to guess that it is due to improper processing.

If you are getting "silver"ey blotches, that suggests improper fixing i.e. residual silver was left in the image to darken.
 
It is possible that your problem is unique to your geographic area. You may have to set up a series of long term tests to establish that. Set up the same print from the same processor in various framing and mating situations. Also it could just be sun damage to the emulsion. Get some new prints, stick them in typical frames and place them where the sun hits them on a daily basis. It may also be a humidity problem.

I have a hunch that the only way to get to the bottom of this is through detective work and cooperation with the processors.

There are many professional photographers on this web sight who know a lot more than I do, perhaps one of them will chime in.

Having these tests set up, will assure your clients that you are diligently looking for an answer to the problem.

John
 
That happened to a photo we framed some years ago. When it came back, I sent it to a conservator. (It had collectible value.)

The conservator speculated -- he wasn't sure -- that the damage was from the high-alkaline environment of the buffered mats & mountboard we used. He also said high humidity might have contributed to the damage.

Never did get a firm analysis, though.
 
Boy, ya just can't win!

If the acid don't getcha, the alkaline will.

I still think it's the photo lab.
 
Ya said it Ron. I'm getting conflic both ways. You guys saying that it's the lab (I'm kind of thinking of siding with you) and the lab is saying it's the frames. I think it might be a combo. I figure the prints may not have been properly printed or washed and may have even used a cheaper paper and this coupled with the non acid free boards ( maybe in some cases-cardboard), the reaction may have been strong. I guess it doesn't help that I live in Hawaii where the humidity and sun are a huge factor. Talk about not catching a break. thanks for all your help. I think I see a clearer picture now. If anyone else can lend an ear, I'd love to hear it.
 
hawaii photog -

For what it's worth, these are extracts from my notes on photographs. They are taken from a number of sources. A very good reference is also listed below. The problem could well be coming from a number of sources - processing plus suspect contact materials plus high humidity and temperatures.

John has a very good idea - make several samples, put them in different environments and see what happens. Can you interest a high school science class???

Deterioration

All silver based photographs are subject to sulphur damage. This will appear as yellow/brown stains and overdarkened blacks (tarnish). Light areas may fade, and the image tone shift to yellow/green. Some sources of sulphur are poor processing (thiosulfate fixers), poor quality storage papers and paperboards, rubber based products (e.g.some adhesives, rubber bands) and air pollution.

Oxidation can cause silver based photographs to yellow. This is usually caused by insufficient fixing, which leaves residual silver salts in the paper, or by insufficient washing.

The silver particles in gelatin emulsions can, under humid conditions, migrate to the surface of the photograph where they are vulnerable to chemical deterioration. This is why silver gelatin prints and negatives are prone to “mirroring”. This condition is generally caused by external oxidants – peroxides produced by poor quality contact papers, ozone from air pollution and photocopiers and plain old atmospheric oxygen.

High humidity and temperature accelerates deterioration.


3) “Mirroring” is most common with gelatin emulsions (negatives or prints). When exposed to high humidities it softenens, allowing silver ions to migrate to the surface. When that happens, and they are exposed to oxidative pollutants, they can turn into silver metal particles. This is called “mirroring”.

4) The image in modern silver gelatin developing out papers (most commonly found 1905 to the present) is made with filamental silver particles. These are quite large when compared to the very tiny photolithic silver particles used in other 19th century silver based photographs (collodian, albumen, silver gelatin printing out papers). Because photolithic silver particles are so small, they are very reactive chemically, and so are more prone to damage from poor quality contact materials and atmospheric pollutants.

Care and Identification of 19th Century Photographic Prints, by James Reilly, Eastman Kodak Co. 1986

Rebecca
 
Thanks Rebecca! You've been so helpful. There is a lot I have to digest. I will do that experiment with the samples and I'll post my findings once I finish.
 
I looked for my article in PFM (or maybe it was Decor) but didn't find it. It was either 2000 or 2001 issue Aug - Oct, it was called the Photography issue and was very specific about these photos and the mirroring etc. I had taken a b & w for my neice and they were doing the processing for a gift for her father. They did find some one to do the fiber base. Anyway also at that time a photo came back we had framed 6 mo. earlier and I had the article in hand and she returned to the photographer. I think they may have used their color processor to do this.
 
Would Rebeca or someone else correct me if I'm wrong but "ACID BURN" (which was preported to be the original culprit) usually leaves a Brownish stain on work (at least the cases i have seen did) .Not a silvery discoloration. I did notice in Rebecca's quotes some statements that to my understanding sounded very much like what Hawaii is decribeing.( #3-4) also Jim's conservator's explanation is what I was refering to in my questioning the type and quality of the materials,and yes different Phs can cause different reactions from what little I know ,depending on the Photo developing process.
But with the increased information and text I too would look more seriously at the processing.
BUDDY
 
Jpete,

When you say they used the color processor, do you mean they used it to process silver gelatin? Could one actually do that and get a result? I'm quite fuzzy on color development chemistry, but the concept seems odd to me. (But then so do many things that I know little about! :D )

Rebecca
 
Hi Buddy,
Yes I did at first wonder about the acid burn and that is because my prints do have predominately an orange and or bronze discoloration. But, there are spots on some of the prints that are silver and that show up in the dark areas. When I asked a lab about them they said it was acid burn and that the silver comes out when the acid pushes it though the paper. Here are some emails from that printer:

From the pictures you sent it seems to be a very clear case of acid burn. On one of the images you can even see where the edge of the matt board was. Another way to check if matt board is bleeding acid is to look and the interior edge of the cut matt board. When it is new it will appear very white. After a short time it will begin to turn yellowish like a newspaper does. That means that the acids are escaping. If you don't have the image under glass there isn't any place for the gases to be trapped so it doesn't seem to matter. But when it's under glass the gases are trapped and begin to react with the photographic paper. If you check the same thing on a piece of acid free matt board it will always stay white it wont change color even years later.

Yes, it can sometimes be a silvery color. It depends on the photographic paper and the type of acids in the matt board. The silvery look comes from the silver halides rising to the surface of the paper. Sometimes this happens merely from age. You'll see it on old black and white photos from the turn of the century. The coppery color is the most common.

Does this sound familiar to all of you?
thanks,
lisa
 
Yes, it sounds familiar. It sounds like a lab operator with just enough information to be dangerous.

If there are lines or marks on the prints that correspond to the beveled edge of the mat windows, I would suspect some mat involvement.

The idea of glass "trapping" the acids and increasing damage is, I believe, just plain silly. Glass should always be used with mats, or when framing any other paper product. Damage from poor mats is caused, primarily, by direct contact.

I just can't imagine even garbage mats causing the kind of damage you're describing in 2-5 years - especially on an RC paper.

This is a common dilemma for photographers. If a photograph deteriorates before it's time, is it the fault of the photographer, the photo lab, the framer, or the customer who slapped the photo in a dime-store frame up against the glass?

[ 02-16-2004, 08:45 AM: Message edited by: Ron Eggers ]
 
Rebecca, I should have been more clear. I think these pictures may have been a copy of an old photo done with todays black and white film which can be done through a color processing machine machines. This topic has had me doing more on-line research, which I enjoy.
 
Frames leaking acid, mats pushing acid through the back of the paper and damaging the prints, glass trapping dangerous gases inside and allowing them to damage the frame, hmmmmmmmmm....

I know verrrrrrry little about photographic processes other than the Forensic Photography Class from college, where we processed our own black and white photos by hand. But,as a chemist the above information is BULL DOODOO.

[ 02-17-2004, 11:00 AM: Message edited by: jvandy57 ]
 
Lisa,
It seems that if the photos are doing this, no matter how they are framed, then the common denominator is the photos themselves. How can the lab just lay blanket blame on the matting/framing? Does the lab have any recommendations on how to frame these so that they won't discolor?

edie the hmmmsomethingdoesntsmellrighthere goddess
 
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