Re: [APML] Copygraph finished and hypering Q

[KGKIRKLEY@aol.com]

In a message dated 3/10/03 11:04:45 PM, jmirtle@shaw.ca writes:

>Brian,
>
>    Hypering does not increase speed, it just stops film from slowing down
>
>under exposure to faint light. You probably have good density on the moon
>at
>
>4 seconds. I would have gone for 1/250 to 1/1000 at f4.5 - but that's just
>
>me. I don't have any good moon pictures....
>
>
>
>Is the moon back again already??
>
>
>
>John Mirtle
>
>Calgary, Ab. Canada

John:
Sorry, but you are incorrect about hypered Technical Pan film.
The speed of Tech Pan varies with the type of developer used and the length 
of development. In a fine grain developer like Technidol it's speed is rated 
as 16 but in Dektol it is about 200.

Now, when you introduce hypering, it's speed increases to over 250 (in D-19 
undiluted) and it's reciprocity is dramatically reduced.

Kent Kirkley
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