Fogged Paper To Do List - Agfa Brovira Speed Grade 4 BH 310

[Mustafa Umut Sarac]

I have just paid for that 5x7 100 paper to ebay seller from israel . I dont have any idea about fogged papers and I think fog means half self exposed paper or film.

What can I do mostly to prevent effects before expose and expose and after expose.

This could not be true but I remember people uses extreme diluted hc110 for old films and long development times.

And I read also - this could be not true - more expose and shorter development times just opposite to above.

I have metol , d23, diafine , d76 and dektol and kodak fixer powder package.

I will shoot asphalt , car tire spin burn like extreme deep black , graphic like dirty city images with 350 polaroid to paper negatives.

Umut

 

[bernard_L]

Benzotriazole. Nominal concentration 0.3g/litre of working developer solution. Increase to 1g/litre if necessary.
After development and fixing, you might try Farmer's reducer to cut the fog. Either
potassium ferricyanide + fixer
or
potassium ferricyanide + potassium bromide
In either case, re-fix and wash. Search this and other forums for details.

 

[Simonh82]

Or use it for lith printing. I know this would mean making a small investment in additional chemicals but Brovira is great for lith printing. It also has the added advantage of rarely showing fog on old papers as you so heavily over expose (usually by at least 3 times) and then develop in such dilute lith developer that the fog really doesn't show compared to the image forming exposure.

 

[henpe]

I have been reading about the phenomena that a significant exposure to intense red light cause an exposed photographic material to get back towards it's unexposed state. I cannot recall the name of the phenomena. In the textbook that I read, the authors claimed that the effect could be utilized to e.g. lift shadow details in prints or to "un-fog" fogged paper. If I recall, you had to expose a fogged paper for several hours in order to get it "un-fogged" (so it is not a very practical method). Maybe a internet search can give you more details?

 

[Thomas Bertilsson]

You have two issues with older paper: Fog and contrast. We must think of them as separate things.

1. Contrast - Since the paper will have lower contrast than when it was new, you must develop your negatives to suit the contrast of the paper as it is today. You may think of using a higher contrast film developer
2. Fog. The way I have dealt with this in the past is that I print using my normal print developer. No benzotriazole added. Then when the print is finished and washed, I use ferricyanide bleach to bleach back the fog. This also increases the contrast, so be prepared for that. This has worked well for me and others in my area whom I have helped with old fogged paper.

All of them have since purchased fresh paper when they see the benefit.

Good luck.

 

[David Lyga]

Hi Mustafa,

Dilute your Dektol about 1 + 5. Then:

To deal with VERY age-fogged paper, remember that the paper does not see any difference between age-fog and emergent shadow detail. They are one and the same thing. Thus, it becomes mandatory to expose such paper well above the lower portion of the characteristic curve so that any image detail will be ABOVE such fog threshhold. With such badly fogged papers you still have a chance, but it does take work and preseverance.

Two things must be done: 1) during development I use BOTH restrainer (BZ or PB) plus baking soda (sodium bicarbonate, try 10g per liter, more or less if necessary) in order to greatly slow the development process down. The need for this is to HOLD BACK that damn fog. 2) Then, still there will be some fog, so after fixation, you will immerse the print into a dilute Farmer's Reducer.

One of the essential things to remember if you are dealing with VERY fogged paper is this: your enlarger exposure can get to even five stops more than with fresh paper. You have to 'burn in' that image and, as result, might have problems with highlight separation (after all, how much of that characteristic curve can you 'steal'!?!?!?) It is frustrating but amazing results can be obtained with patience, perseverance, and fortitude (and, time!) Coin tests, throughout, will determine the real fog level. And, forget about using a high contrast filter with fogged VC paper. You will not achieve anything better, as the paper has lost that ability. With fogged paper, severly fogged, you are after every ounce of contrast you can get ahold of. And that is where the dilute Farmer's comes in handy: it slightly increases contrast in paper (but NOT in film). - David Lyga

 

[henpe]

Regarding my previous post:
The effect is known as the Herschel effect after its discoverer (1839). Herschel discovered that a developed, but not yet fixed image can be bleaced back by strong exposure to long wave radiation (red light or IR). He also discovered that a latent and undeveloped image can be bleaced back in a similar manner. His findings were first forgotten, but then rediscovered as a mean to e.g. reduce the contrast of a image printed on very hard grade paper, or as a method to regenerate old fogged paper. I have an old (1940) scientifical textbook about photographic processes that describe the theory behind the effect and complement with some interesting illustrations and diagrams. Unfortunately the book is in Swedish.

 

[Mustafa Umut Sarac]

Thank you very much everyone,

henpe,

Check your pm.

Umut