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  1. #1
    Snapshot's Avatar
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    Pyro Developer and Thin Negatives

    Hi All,

    I've been experimenting with a personal pyro developer fomulation. Fortunately, the negatives appear to have good density, low base fog and excellent sharpness. However, the negatives appear to be nearly as dense as negatives developed with FX-37, which has a tendency to produce dense negatives.

    Would I gain additional benefit if I develop the pyro negatives to be thinner? Should I be developing the pyro negative to be thinner or is this dependent on the type of pyro formulation?

    Any thoughts?
    "The secret to life is to keep your mind full and your bowels empty. Unfortunately, the converse is true for most people."

  2. #2
    TheFlyingCamera's Avatar
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    Print them first and see what you're getting. They may be fine, or they may be dense. Best way to tell is make some prints. If your exposure times double or triple over a non-pyro developer, they may be too dense. I say MAY because you'll need to look at what is happening to your highlights and your shadow details. If your highlights are way blown out, but you have good shadows, then you're overcooking your film. If your shadows are too thin, adjust your exposure (add more) then cut your development time to bring the highlights back down. Many people seem to think the first time they see a pyro neg that it is actually too thin, when in fact the stain makes up for the seeming lack of density, so I'm surprised that you feel your pyro negs are too dense.

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    Quote Originally Posted by Snapshot View Post
    Hi All,

    I've been experimenting with a personal pyro developer fomulation. Fortunately, the negatives appear to have good density, low base fog and excellent sharpness. However, the negatives appear to be nearly as dense as negatives developed with FX-37, which has a tendency to produce dense negatives.

    Would I gain additional benefit if I develop the pyro negatives to be thinner? Should I be developing the pyro negative to be thinner or is this dependent on the type of pyro formulation?

    Any thoughts?
    The printing density of negatives developed in any staining developer (Pyrogallol, Pyrocatechol, Hydroquinone, Amidol, etc., etc.) is virtually impossible to evaluate by eyeball. You need to print the negs or run them through a transmission densitometer - or both. Depending on your printing process, the color of the stain can be important and stain color is determined by the formulation.
    Tom Hoskinson
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  4. #4

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    I agree with the above. In fact, Gordon Hutchings, author of the "book of Pyro" and inventor of PMK developer, has said that pyro developed negs will look impossible to print and that you need to actually make prints to evaluate them.

  5. #5
    Snapshot's Avatar
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    Well, it would seem some prints are in order before adjusting my development time. I asked the question is because I was expecting thinner negatives but instead I had negatives that appeared to being nearly as dense as negatives developed in FX-37.
    "The secret to life is to keep your mind full and your bowels empty. Unfortunately, the converse is true for most people."

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    Quote Originally Posted by Snapshot View Post
    Well, it would seem some prints are in order before adjusting my development time. I asked the question is because I was expecting thinner negatives but instead I had negatives that appeared to being nearly as dense as negatives developed in FX-37.
    Why were you expecting thinner negatives?

    What developer are you using? What dilution and development time? Which agitation scheme ?
    Tom Hoskinson
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    Everything is analog - even digital :D

  7. #7
    Snapshot's Avatar
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    Quote Originally Posted by Tom Hoskinson View Post
    Why were you expecting thinner negatives?

    What developer are you using? What dilution and development time? Which agitation scheme ?
    I was expecting thinner negatives due to numerous reports that pyro developers, such as PMK, produce thinner negatives. I was using a custom formulation, consisting of Metol, HQ and Pyro. Approximately, 1.7g of developer was used in a litre of solution. TEA was used as the alkali/accelerator. The dilution ratio was 1+100 (1 part developer concentrate and 100 parts water). I developed APX 100 for 10 minutes using a 30 second initial agitation, and 10 seconds of agitation every minute.

    My hope was to get a sharp pyro based developer. Since I liked the PC-TEA and 510-Pyro concentrates, I experimented with a new developer formulation. I was very satisfied with the sharpness and detail rendition but I considered the negatives to be too dense to be typical. Perhaps, I'm worried about nothing.
    Last edited by Snapshot; 10-16-2007 at 03:18 PM. Click to view previous post history.
    "The secret to life is to keep your mind full and your bowels empty. Unfortunately, the converse is true for most people."

  8. #8

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    Quote Originally Posted by Snapshot View Post
    I
    My hope was to get a sharp pyro based developer. Since I liked the PC-TEA and 510-Pyro concentrates, I experimented with a new developer formulation. I was very satisfied with the sharpness and detail rendition but I considered the negatives to be too dense to be typical. Perhaps, I'm worried about nothing.

    I develop most of my negatives in either Pyrocat-HD or Pyrocat-MC. In terms of density they do not look visually much different from negatives developed in non-staining developers.

    All of the Pyro staining developers I have used, including PMK, Pyrocat-HD and -MD, and WD2D, are acutance developers when developed with normal agitation, and high acutance developers when developed with minimal agitation.

    In your Pyro formula, what is the role of the HQ? My thought is that HQ requires such a high pH for threshold activity that it would not be activated by the pH of TEA?

    Sandy King

  9. #9
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    Quote Originally Posted by sanking View Post
    I develop most of my negatives in either Pyrocat-HD or Pyrocat-MC. In terms of density they do not look visually much different from negatives developed in non-staining developers.

    All of the Pyro staining developers I have used, including PMK, Pyrocat-HD and -MD, and WD2D, are acutance developers when developed with normal agitation, and high acutance developers when developed with minimal agitation.

    In your Pyro formula, what is the role of the HQ? My thought is that HQ requires such a high pH for threshold activity that it would not be activated by the pH of TEA?

    Sandy King
    Hi Sandy,

    I have a pH value close to 10 for the formula (estimated from test strips as I don't have a digital meter yet). I was surprised at the 'relatively' high pH but that's what the test strips indicated at 1+100 dilution. The HQ was to bump up the contrast a bit. It's my understanding that pyro-metol formulas tend to be of moderate contrast. Since I use VC paper and the pyro stain acts a contrast mask, I wanted a little more contrast to compensate.

    The formulation that I used is as follows...

    TEA...............100ml
    Metol.............2.0g
    Hydroquinone...5.0g
    Pyrogallol........10.g
    "The secret to life is to keep your mind full and your bowels empty. Unfortunately, the converse is true for most people."

  10. #10

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    Quote Originally Posted by Snapshot View Post
    Hi Sandy,

    I have a pH value close to 10 for the formula (estimated from test strips as I don't have a digital meter yet). I was surprised at the 'relatively' high pH but that's what the test strips indicated at 1+100 dilution. The HQ was to bump up the contrast a bit. It's my understanding that pyro-metol formulas tend to be of moderate contrast. Since I use VC paper and the pyro stain acts a contrast mask, I wanted a little more contrast to compensate.

    The formulation that I used is as follows...

    TEA...............100ml
    Metol.............2.0g
    Hydroquinone...5.0g
    Pyrogallol........10.g

    A pH of 10 is much higher than I would have expected from TEA at this dilution. I have an electronic pH meter and would get no more than about pH 9.2 with this dilution.

    However, there could be significant synergism between the three reducers that activates the hydroquinone at a lower pH?

    But why HQ and not ascorbic as the third reducer? Were you concerned that there would be a loss of sharpness as Hutchings suggests with Pyrogallol + ascorbic?

    Sandy

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