Ready-Made emulsion speeds?

Discussion in 'Silver Gelatin Based Emulsion Making & Coating' started by DannL., Oct 16, 2013.

  1. DannL.

    DannL. Member

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    I am curious as to what speeds are available in ready-made emulsions such as Liquid Light, etc? Primarily I would be interested in faster speed emulsions. I'm currently using Liquid Light at ISO 1 with good results.

    I understand that by adding developer to an emulsion a speed increase may be realized. Does anybody know what ratios of what developers = what speeds?
     
    Last edited by a moderator: Oct 16, 2013
  2. jnanian

    jnanian Advertiser Advertiser

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    hi dannL

    you might call rockland colloid and ask them.
    they might have data on that subject .. but from what i remember ...
    they stopped making that recommendation because it degraded the emulsion ( afterwards ) ...
    one way i have increased the speed of my emulsion is by letting it age a little bit.
    i have noticed it gets a bit more contrasty and speedy if it is older ...
    are you using it in the darkroom or as a negative-material ?
    depending on the outside light the speed changes .. more blue light the faster the emulsion is ...
    i did my best to try to figure out what time of year the most blue light is .. ( new england )
    and mid day ( 11-1pm ) without a cloud in the sky ... usually in the summertime
    BUT ...
    and you are making photographs in the snow/winter, you get reflected blue light as well as atmospheric ..

    hopefully i haven't disinformed you too much !

    good luck !
    john
     
  3. DannL.

    DannL. Member

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    Thank's John. I'm coating glass plates for use in my cameras. The 5x7 camera is designed to be hand-held easily and I would like to "up the speed" of the plates so that I can use a faster shutter speed and smaller iris sizes.

    If I could achieve ISO 100, that would be lovely. But, ISO 99 would be fine also . . . ;-)
     
  4. jnanian

    jnanian Advertiser Advertiser

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