Randy, I'm the guilty party in at least some of these instances. It's not all wrong; there are only a few obvious errors. It is also less complete than the fairly up-to-date information that Greg Davis posted above. Greg's information is identical with the same specification I got directly from ANSI a few years ago, and with minor exceptions from the 1951 specifications in The Camera Repairman's Handbook. The older specification differed by including the 1/4" additions to 2x3 and 3x4 film sizes. The 1998 version adds the "J" dimension for the thickness of the septum in only the 11x14 and 14x17 holders, film sizes that the 1951 version did not cover.Originally Posted by Randy Moe
Here is a reply to an earlier posting of Randy's link:
It should be noted that some of the information in this often cited illustration may be questionable. The depth to film surface distance (the "T" distance) as shown in my 1951 copy of the ASA standards is to the back, not the front, of the film. The Exposure Height measurement given is apparently the ASA D2, not the appropriate D3, measurement. The Exposure Width measurement is the E1 maximum, not the appropriate E3 measurement. The Retaining Tab Location is a maximum; the minimum is .010" less. The Length dimension is a minimum: ASA specified no maximum. The Width is a maximum: the minimum is about .031" less. The Distance to Exposure Field is a maximum: the minimum is .020 less for up through 5x7 holders and .030 less for 8x10 holders. I don't have ASA information on holders larger than 8x10. Dimensions in newer versions of the ASA or ANSI standards may differ.
At least the provider of the information Randy cited tried to be of service without violating copyright laws. Now that we are on the path to assembling comprehensive and accurate information, we should lay that citation to rest. This will be an ongoing process, and eventually should encompass the variations with which different photo equipment makers have plagued us for so long.
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