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  1. #1

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    modified pyrocat-hd

    Anyone used Blackthorn pyrocat-hd from www.photography-courses.com ? Any idea what the modification could be? The mind boggles. Bogey

  2. #2
    Ian Grant's Avatar
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    No, guess they've just modified it to make it unique to them.

    But it's interesting they are running a School of Photography, not one has an academic photography based qualification and they can't award any valid qualifications to their students either

  3. #3

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    Quote Originally Posted by Ian Grant
    No, guess they've just modified it to make it unique to them.

    But it's interesting they are running a School of Photography, not one has an academic photography based qualification and they can't award any valid qualifications to their students either
    This does matter if you are 'teaching' youngsters with aspirations in this field, tho I would still say that anyone seeking an apprentiship will be judged by a prospective mentor on the quality of their work and their attitude! For those later in life looking to develop their hobby, it matters not, but certainly take the point!

    I would bet that the pyrocat HD they sell has either no mods or mods that make no difference....just a hunch as they make no claims as to the benefits of their special brew if I remember correctly...

  4. #4
    Leon's Avatar
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    it's a bit unfair of them not to mention Sandy King in their description of the product .. they may have modified it in whatever way, but it is still pyrocat HD. I reckon this is a little disrespectful. They mention plenty of other developer developers (!)

  5. #5

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    We have to give credit where credit is due and King has made an excellent developer, one that IMO does not need any "modifications".....

  6. #6

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    I might give it a go, I don't think there is anywhere else in the UK that sells it so Thanks for the link. I really don't want to mess around mixing it up myself.

  7. #7

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    The mods include the use of Pyrocatechol instead Pyrogallol to make it less toxic. A few very slight changes have been made to the quanities of other ingredients in order to up the acutance and reduce the grain further than the original Pyrocat HD. The exact changes are known by the Blackthorn's founder lecturer Brian Walker ARPS, although he doesn't publish these changes.

    With regard to the qualifications held by the Blackthorn's lecturers... All are either current or retired professional photographers. Which would you rather learn from??... An academic that has never taken a professional photograph or a real photographer? They are all either Associates of Fellows of the Royal Photographic Society. The Blackthorn Centre's web site clearly states that it does not offer any full time courses and offers courses aimed at amateurs and professionals interested in furthering their knowledge of the subject.

    The Blackthorn Centre regulaly puts students forward for Royal Photographic Society awards and City & Guilds qualifications. How many schools do you know of that can acutally award qualifications themselves?

    Pete Bown MPhys(hons), DipEd, LRPS
    The Blackthorn Centre School of Photography's web designer and occational lecturer in Photography related IT

  8. #8
    Mateo's Avatar
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    Quote Originally Posted by petebown
    The mods include the use of Pyrocatechol instead Pyrogallol to make it less toxic...
    That's an odd modification considering the fact that Sandy Kings formula has never had Pyrogallol in it.
    "If I only had a brain"-Some badly dressed guy made of straw in some movie I think I saw

  9. #9

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    Quote Originally Posted by petebown
    The mods include the use of Pyrocatechol instead Pyrogallol to make it less toxic. A few very slight changes have been made to the quanities of other ingredients in order to up the acutance and reduce the grain further than the original Pyrocat HD. The exact changes are known by the Blackthorn's founder lecturer Brian Walker ARPS, although he doesn't publish these changes.

    With regard to the qualifications held by the Blackthorn's lecturers... All are either current or retired professional photographers. Which would you rather learn from??... An academic that has never taken a professional photograph or a real photographer? They are all either Associates of Fellows of the Royal Photographic Society. The Blackthorn Centre's web site clearly states that it does not offer any full time courses and offers courses aimed at amateurs and professionals interested in furthering their knowledge of the subject.

    The Blackthorn Centre regulaly puts students forward for Royal Photographic Society awards and City & Guilds qualifications. How many schools do you know of that can acutally award qualifications themselves?

    Pete Bown MPhys(hons), DipEd, LRPS
    The Blackthorn Centre School of Photography's web designer and occational lecturer in Photography related IT
    Pyrocat never used pyrogallol. I imagine this is why King called it Pyrocat, because it uses catechol as well as phenidone as the developing ingredients. In my experience reducing grain and increasing acutance are mutually exclusive terms, you can do one or the other, but not both. I am no expert at designing developers and certainly cannot speak for King, but if I understand my developer chemistry correctly Pyrocat HD uses Sodium Bisulfite as a solvent to reduce grain, lowering the amount of this will increase grain and acutance, increasing it will reduce grain and also acutance. Since the only other ingredient is Potassium Bromide, used as an antifoggin agent and which has minimal effect on acutance and grain size I am curious to know how is it you acheived this lower grain greater acutance effect.

    I find it very hard to beleive you have improved on a developer that produces no grain on TMX 400....Please enlighten me.

  10. #10
    Leon's Avatar
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    yes - pyrocat is short for pyrocatechol is it not ....? Definitely never seen a recipe for sandy's P'cat HD with pyrogallol in it.

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