Re: (IAAC) Markarian 205 - 8inch F/10

At 02:33 PM 6/8/98 -0400, you wrote:
>>In fact, generally the only NEGATIVE effect of using narrow-band
>>filters (aside from false color distractions) is image darkening!
>The only caveat to this would be a case where any object had a
significantly bright emission feature which was excluded by a particular
filter's bandpass. Are there any common examples of this folks know of -
maybe certain types of emission features being darkened relative to the
background by an H-beta, or by some of the "custom bandpass" filters? Just
Numbers of planetaries seem to suffer from narrow band filters particularily
OIII filters. The Catseye is one and I think the Eskimo nebula is another
but there are others I have seen but I can't remember offhand which ones. 
Nice to be back online again. My computer had a dead video card and it took
the place I got it from five weeks to get a replacement (under warranty).
Impressive service :-not.
Nick Martin, Bonnyton house, By Ayr, Ayrshire KA6 7EW ,Scotland, UK.
 Longitude 55 24'56" Latitude 4 26' 00".
"Thou star of evening's purple dome
 That lead'st the nightingale abroad,
 And guid'st the pilgrim to his home." 
   To the Evening Star by T.Campbell