Re: [APML] Ektachrome E or Elite 200 asa.

[Gene Horr <genehorr@texas.net>]

> dimitris kolovos wrote:
 
> I see from this mailing list that Ektachrome 200 asa slide film is consindered as
> perhaps the best astrophotography film.From my experiense no one slide film is
> sensitive enough for 6.3 or higher f/ratios.

I've had good experience with it at f/4.5 - f/6.    

> Is it worthy for some one to try it,espesially on galaxies?

I haven't tried it on galaxies.  With nebulae (sp?) the red response is
noticeably "faster" than the blue response.  But there doesn't appear to
be any red tint to the stars, even the dimmer ones.  From this I would
hazard a guess that the response on galaxies should be fine.  But I
would expose it more as a 200 ASA film time than a 300 ASA.  The 300
speed appears to be due to the apparantly faster Ha sensitivity.

> And what is the expected time for 6.3 f/ratio?

At a dark site I would go 1.5 hours.

> Is there any comparison  with Royal gold 200 asa film?

Well, if you check the archives IIRC Tony Hallas has had good results 
with it hypered.  You might want to try RG 400 unhypered.  It appears
to have good sensitivity, but is on the grainy side.

Gene Horr
genehorr@texas.net

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