Is the #6 filter also known as the "Spinal Tap" filter?
“Photography is a complex and fluid medium, and its many factors are not applied in simple sequence. Rather, the process may be likened to the art of the juggler in keeping many balls in the air at one time!”
Ansel Adams, from the introduction to The Negative - The New Ansel Adams Photography Series / Book 2
Has anyone ever heard of one? As in, one step above grade 5, which I've always known as the most contrast available.
I needed a #4 and #5, found three on ebay, #4, 5, and 6, see attached.
Was this for some specific paper?
I can't find any info about a No. 6 filter via Google.
filter numbers and ISOcontrast grades are not the same, unfortunately, but theoretically an ISOgrade 6 exists and can be reached with a tri-color -blue filter in combination with a very bright light source. Inever had a negative that needed such a high contrstbut tested tri-color filters fordual-filter printing.
A manufacturer can name filters them whatever they want.
I once owned Ilford, Kodak, and Dupont filters. On the same paper, each brand's filter # printed differently. The higher the contrast #, the bigger the difference. They were closer in their low contrast #'s, but still slightly different. For awhile, I actually used the differences when looking for a little more nuance.