Re: Volume to weight

From: Katharine Thayer <kthayer_at_pacifier.com>
Date: Fri, 05 May 2006 09:00:50 -0700
Message-id: <E131453E-A9FF-4CE0-9650-F421A0F55598@pacifier.com>

Okay, then by my best ballpark guesstimate, I'm using .6 grams of
actual pigment in 3 ml of coating mix, give or take, which is quite a
lot more than you were using, and when I have time I'll cut back more
and see if I still get the same DMax and a less contrasty tonal scale.
Katharine

On May 4, 2006, at 2:09 PM, Marek Matusz wrote:

> Katharine,
> To answer your question, about 15 cc of tapped carbon black in a
> beaker is 2.5 grams. And every time you open a container with it
> you end up with such a mess.
> I ran out of HP transparency yesterday and used something else (it
> is Crystal Clear brand that I use to print gum negatives). The back
> exposed gum just slides off from it. No good for back exposing. I
> need to get some more HP transparency. Did you mention that one of
> your brands of transparency film did not work as well?
> Marek
>
>
>
>> From: Katharine Thayer <kthayer@pacifier.com>
>> Reply-To: alt-photo-process-l@usask.ca
>> To: alt-photo-process-l@usask.ca
>> Subject: Volume to weight
>> Date: Wed, 03 May 2006 08:14:43 -0700
>>
>>
>> On Apr 27, 2006, at 9:14 AM, Katharine Thayer wrote:
>>
>>
>>>
>>> On Apr 26, 2006, at 2:56 PM, Marek Matusz wrote:
>>>
>>>
>>>
>>>
>>>> To clarify my recipe, my gum mix consisted of 0.25 g of dry
>>>> lamp black from Daniel Smith (or is it called carnbon black?,
>>>> can't remember at this moment), 3 grams of dry gum (I actually
>>>> used 10cc of 14 baume gum which is about 30%)
>>>>
>>>>
>>>
>>> Obviously there's no way to compare this to the amount of paint
>>> I'm using, as we don't know how much pigment is in a given
>>> amount of a given brand of a paint made of a given pigment.
>>>
>>
>> I've been doing some studying to try to find a way to ballpark an
>> estimate of the amount of pigment in my paint, so I can get an
>> idea of how our recipes compare. It could only be a ballpark,
>> since of course paint brands differ in their pigmentation, but I
>> was just trying to get an idea. What I have found has surprised
>> me. For some reason I always thought there would be more vehicle
>> than pigment in paint, but that's not of course the case at all.
>>
>> Unfortunately I've only been able to find general recipes, not
>> pigment-specific recipes, and I've only been able to get amounts
>> in volume rather than weight. Since I have neither powdered
>> pigment nor a scale that weighs that fine (lamp or carbon black
>> are very light pigments) I need help translating volume to
>> weight. Marek, how hard would it be for you to give me a
>> translation of volume to weight for your carbon black? Say, how
>> many tablespoons or teaspoons or whatever measure of volume you
>> might have available is a gram of powdered carbon? Don't go to
>> a lot of trouble, but if it's not too hard, I'd like to know,
>> Katharine
>>
>
>
>
Received on 05/05/06-10:01:04 AM Z

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