Re: [APML] Films responding to Ha, Hb, OIII

[Ray Butler <ray.butler@nuigalway.ie>]

Stuart Heggie wrote:

> Ray, Canadian slang is consistent with American slang: bust is bad. 

Thanks for the explanation! And apologies for committing the ultimate 
faux-pas of mistaking a Canadian for an American. Happens to me too: 
"Hey, you're Irish? Isn't that part of Great Britain?..." To which 
ignorance, I reply: "Yeah, just like Texas is part of Mexico" (;-))

 > So, for star trails it was a very poor performer.

When I think about it, that is not necessarily a bad sign. In a star 
trail, each star spends only a short while on a given part of the film 
emulsion, so it is like a stream of short exposures really. You would 
not necessarily expect a film, whose strength is low reciprocity failure 
over many minutes of sustained exposure on the same point of light, to 
stand out in a star trail. A film with high raw speed but poor 
reciprocity would appear to be more sensitive for that application...I 
think!

Ray "who'd be proud to be a Canadian, too" Butler

> Stuart

-- 
Dr. Ray Butler (ray.butler@nuigalway.ie || ray@physics.nuigalway.ie)
Lecturer, Dept. of Physics || Computational Astrophysics Laboratory
National University of Ireland, Galway, University Road, Galway, Ireland.
Tel: +353-91-524411 ext. 3788   FAX: +353-91-525700

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