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  1. #1
    Ian Grant's Avatar
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    Bauchet B&W Reversal Processing

    First Developer

    Part A
    Sodium Sulphite (anhyd) 50g
    Hydroquinone 15g
    Sodium Carbonate (anhyd) 10g
    Potassium Bromide 8g
    Water to 950 ml

    Part B
    Sodium Hydroxide 19g
    Water to 50 ml

    Mix Parts A+B before Use

    Bleach Bath

    Water 750ml
    Potassium Dichromate 6g
    Sulphuric acid (conc) 10ml
    Water to 1 litre

    ADD THE SULPHURIC ACID TO THE 750ml SLOWLY, DROP BY DROP.

    Clearing Bath

    Sodium Sulphite (anhyd) 100g
    Water to 1 litre


    Second Developer

    Metol 2g
    Sodium Sulphite (anhyd) 10g
    Hydroquinone 6g
    Sodium Carbonate (anhyd) 25g
    Potassium Bromide 2g
    Water to 1 litre


    REVERSAL PROCESSING

    First Developer
    4-14 minutes at 20°C Development by inspection was recommended
    However 8-10 minutes would be a more appropriate as a starting point.

    Wash 5 mins

    Bleach 3 - 5 minutes

    Wash 5 minutes in running water

    Clear 3 minutes

    Wash 30 seconds

    Re-expose - 1 min, 75w bulb at 5 ft (1.5 metres)

    Second Developer
    To Finality (approx 3 mins)

    Wash 30 secs

    Fix in normal acid hardening fixer.

    Wash 15-30 minutes
    Last edited by Ian Grant; 07-28-2008 at 07:23 AM. Click to view previous post history.

  2. #2

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    Thanks. Instead of exposing the film to light, do you know of a way to use another chemical bath to do the same thing?

    Also what about using different acids instead of the Sulfuric? Sulfuric is getting to be too much hassle to use, too much paperwork involved to get it. And shipping expense can be very high since it is a hazardous material.

  3. #3
    Ian Grant's Avatar
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    The alternative to re-exposure are to come, there are plenty of different alternatives but they need a completely separate listing.

    You can buy conc Sulphuric as drain cleaner US/UK with no paperwork so lets use what's best

    Ian

  4. #4

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    Not anymore in the US. Even the lye base drain openers are mostly gone. Can't even buy dilute sulfuric battery acid in the automotive parts stores. I assume I might be able to get sulfuric from the single photo store in town that still carries a good supply of chemicals, but I'm not sure. The damn government has taken most all the good chemicals away from us lately.

    Sorry for the rant.

  5. #5

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    I agree completely

    Quote Originally Posted by Greg_E View Post
    Not anymore in the US. Even the lye base drain openers are mostly gone. Can't even buy dilute sulfuric battery acid in the automotive parts stores. I assume I might be able to get sulfuric from the single photo store in town that still carries a good supply of chemicals, but I'm not sure. The damn government has taken most all the good chemicals away from us lately.

    Sorry for the rant.
    It was only yesterday that I discovered that Red Devil Lye is gone-ola by several years. About the time I bought my last.

    After a lot of internet searching I found the Lowe's has a 2 lb can of Roebic Crystal drain cleaner (IIRC) for $8.

    You might be able to get battery acid still from NAPA.

    You can also get weaker sulfuric acid from sodium bisulfate, aka pool pH decreaser. $6 for 3 lbs, typically. I use it for stop bath. And the pool.

  6. #6

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    You might find this listing of chemicals and common sources useful:
    http://www.sas.org/tcs/weeklyIssues_...re2/index.html

  7. #7

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    How concentrated does the sulfuric acid need to be here?

  8. #8
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    It should be concentrated, 98%, but there's no reason why you can't use less concentrated provided you adjust the amount to compensate.

    Ian
    Last edited by Ian Grant; 08-12-2008 at 10:15 AM. Click to view previous post history.

  9. #9
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    You can make either potassium or sodium hydroxide with Slaked lime from the garden shop and either sodium or potassium carbonate. Calcium carbonate is precipitated. Slaked lime (calcium hydroxide) alone is not very soluble.
    Gadget Gainer



 

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