[APML]Emission Lines Question and missing Veil

["William R. Mattil" <wrmattil@ix.netcom.com>]

Gentlemen,

I have a question that perhaps some of the more knowlegable members
could shed some light on for me. I have tried to image the Veil Nebula
twice now (two seperate occasions) and  failed miserably. The failure
doesn't bother me too much, but without knowing why I am probably
setting myself up for further failures. Set-Ups were as follows:

8" Schmidt Camera (f/1.5) - ST-4 guiding a GM-100 mount. 90mm f/11
guidescope. Side x Side

Film used was unhypered Kodak Royal Gold 100. Exposure times were 30
minutes. 

First Image on the roll was the Lagoon and it turned out ... well, Okay. 
Not a trace of the Veil could be seen in any of the images attempted.
Now I may have been not exactly centered but the FOV is such that *some*
trace should have appeared. The only explanation that makes sense to me
is this. The RG100 may cut off in the Red quicker than I thought and the
Lagoon simply has enough brightness to register. NGC7000 shows up also,
but no Veil. Any ideas would be appreciated.

I have compared the images taken with Sky Charts and confirmed that
portions *should* definently be on the negative. Microscopic examination
of the negative says no. I chose to examine it this way in case the 1
hour Lab got overly enthusiastic about giving me a dark sky :^)

A film change is probably in order for the next attempt.

Any information or sources on the emission lines emitted by this ? And
links to sources would also be appreciated. What is confusing is that
Visual observers seem to like an OIII filter for this object. That would
tend to point to something on the order of ~500nm wouldn't it ?

Thanks in Advance

Bill
-- 
William R. Mattil	| Fred Astaire wasn't so great.
wrmattil@ix.netcom.com	| Ginger had to do it all backwards
(972) 399-4106		| and... in high heels.

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