Re: [APML] Tech Pan Development question

[KGKIRKLEY@aol.com]

In a message dated 1/21/02 4:40:14 PM, flyboy9990@earthlink.net writes:

>Hi Kent,
>
>    I do have some Hypo Clearing Agent too. I'm glad I bought it! I'm going
>
>to start out shooting prime focus with a SCT @ f/10 without a filter. I
>
>thought later once I get useto it I might try a Ha filter. I don't want
>to
>
>get into the filtered shots yet. I would like to but want to practice with
>
>it first. I guess it would help to extend the rinse times ah?
>
>Jim

Jim:
Are you using Hypered Tech Pan (I hope?).
Tech Pan is an incredible film. It is very red sensitive, which is why it 
works so well for emission nebulae. This is where the Ha filter comes in. For 
objects that aren't red emitters, like most galaxies, don't use a filter. 

I don't intend to sound negative, but an f/10 optical system will mean long, 
long exposures. Depending on object, easily an hour or much more, even if 
it's hypered.

Kent Kirkley

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