Quote:
Originally Posted by Paul Haese
I have been collecting with this very same orientation. The Mono image looks good.
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thanks for that Paul - yes I thought the straight Ha colour was pretty intense.
Looking forward to seeing your version.
Quote:
Originally Posted by strongmanmike
Nice work Rusty  Eta really looks good in Ha.
yes having NB filters certainly helps in moonlit skies, using 12nm NB filters I have noticed that there is still a tad more contrast under moonless conditions and the moon can also shine down the tube at certain angles and create havoc too, especially with a Newt because the side light input is up near the end of the tube, although this is much less likely in a dome  To hopefully help under the Moon, I have a full set of Astronomiks new line of 6nm NB filters on their way, this should improve NB imaging under moonlit skies..?
Mike |
Cheers Mike
yes I was pondering the moonlight angle and was thinking either an extension tube was needed if not shooting south - or atleast a baffle (or dome). it also got me thinking about filters, one can take a photo of the moon in Ha no problem at all so I was thinking what is it that actually makes a NB filter so useful in moonlit skies - I've come to the conclusion (whether rightly or wrongly
) that the filters generally only allow 'straight' light through the filter and onto the sensor so the stray moonlight while going down the scope is less likely to hit directly square - kinda like a polarising filter (I think). anyway that was my ponderings as I was sitting outside under the heavens.
I bet you're hanging for the 6nm's they're a new release I think? baader seem to have the best value nb filters I don't know how they compare with astronomiks - although the astronomik ccd cls is clearly superior in transmission than the baader equivalent.
Quote:
Originally Posted by Placidus
Very nicely processed, Rusty.
With narrowband filters, if the moon is say in Pisces, then you can image bright objects in the deep south happily for all but a couple days either side of the full moon.
Any sort of moon at all say just 15 degrees away is as Mike says, a disaster, and for really ultra-faint stuff, one needs the new moon. Also thin haze, which often means good seeing, is bad if the moon's bright.
Nice work.
Mike
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cheers Mike - good to know to steer clear a few days around the full moon and to watch the haze - I wasn't too sure how close you could go. Is it also true the OIII is a bit more susceptible to moonlight than Ha (which blows my conclusions above out of the water
)?
I think the tilt is a result of the OAG - as sometimes its there and other times its not, I don't really require the thinline anymore one so may have to start investigating more sturdy options.
Pretty happy in how the canon 600d handled 7 min subs - the sensor was at 29 degs most of the night.
I also took flats with the Ha - i'm not sure whether people do that or not - I was worried about noise. on another note I didn't use any darks for this just flats and dithering.
