I've been wanting to image this with my new Skywatcher ED100 refractor for a while. Last night was the first time in weeks that there's been a bit of a break in the sky. So here it is. I think it doesn't look too bad. SW ED100 at F7.2 with Orion 0.8X focal reducer, 84 x 1 minute subs unguided, Pentax K-x.
Very pretty. I think the very small amount of chromatic aberration in these scopes is nice as it makes the blue stars really look spectacular. Lovely natural looking colours.
-Cam
I'm very impressed with the SW ED100. The stars are pin point and the contrast way better than my reflectors. It's actually better than my 6" F5 Newtonian in virtually every way.
Very nice Kevin. I too like the colour palette. I should have set up last night as well. the light clouds tonight are as frustrating as anything. Tonight the Butterfly Nebula was on the menu but alas unless these clouds rack off it will be just frustration to chew on.
Yes looking good! Man that's a lot of subs. I wonder, is there an optimum number to do at 1 min? I thought I read once that 30 is pretty much the sweet spot.
First clear night down here for ages, I've been able to try 3 min unguided subs for first time! Doing Eta Carinae right now, so much better looking at these length of subs.
There is no sweet spot, just diminishing returns. It all depends how deep you want to go. When I used to do video deep sky, it was normal to get thousands of frames. But thousands of frames on a DSLR for each object would kill it pretty quick.
Just take some shorter exposures too so you can keep the star colours intact, otherwise you'll max out all the R, G & B pixels and you'll only get white stars.
-Cam
Yeah I've noticed DSS seems to dilute the colours...often my single 30s frames have got more colour in them I just figured I didn't have enough subs but if you're taking 84 minutes and still seeing that phenomenon
I always find that dss washes the colour out too. But when I bring it into pixinsight, and esp when I recalibrate the colours to white, most of the colour returns. But I always end up increasing the star saturation. Apply a starmask so u don't end up with fluoro nebulas!