StuartT

Fair enough. Nothing wrong with a bit of judicious trickery in the interests of a striking image 👍

Outstanding! Don't you mean 10:47 tho?

beautiful image! So I am intrigued as to how you got the colour. Whenever I use either a wedge (on my frac) or a white light filter (on my SCT) I only ever get a white image of the sun

Could be better, but could be a lot worse! 10:35 and 10:56 respectively, 90mm achro, f/11 with solar wedge and 2x Barlow, CanonEOS750D ISO400, 1/800sec ISO800, 1/40sec

Nice tip! I've ordered some reflectix and some neoprene sheet, so I shall get creative!

thanks. Good tip! Probably forms a rather nicer cylinder than my cardboard too. I'll give that a try

I am still very much learning how to do this processing stuff. Sometimes after my three 'stretches' using levels, I find the sky is still a little too light. So I have been reducing the offset in Photoshop's Exposure adjustment. It nicely darkens the sky while not messing up the target. Does anyone else do this?

absolutely amazed by how well my cardboard dew shield worked! No dew at all on the scope even after 3.5 hours!

To be honest, cardboard works great! I made this one last night out of an old box (I had no neoprene to hand!) and it worked perfectly. No dew at all in three and a half hours of imaging!

My visibility is slightly restricted where I live (and I don't have a car). My best view is in the region NE to SE so I need to be able to find targets that are in that zone after 11pm (as it doesn't get dark until then at this time of year). Alternatively stuff that's at high altitude. So how do you all select your targets? Are there apps you use? I have stellarium which tells you where stuff is, if you already know what you want. But it doesn't make recommendations

ok, I shall keep an eye on it. Thanks. I have ordered a dew heater band thingy which should arrive next week

ok, so just as a stop gap for tonight, I have fashioned a makeshift dew shield from cardboard (I don't have any neoprene to hand). Should I add any aluminium foil on the inside or outside? Or should it work as it is?

Well... I am stacking them now, so let's see what we got. It wasn't properly dark where I live until 11ish, so I was up late 😴 Thanks for explaining. I have often wondered about this

ah! I see. thanks. So I guess a dew shield wouldn't be effective if the scope is pointed at the zenith (since the heat can rise straight out)? I have invested in one of those dew heater bands (though I am now puzzled by how those don't mess up your careful telescope cooling...)

Dew shields... ok, now this has always puzzled me. How on earth can a cylinder with an open end protect against a gas? Dew is water condensing out of the air as the temperature drops. Air is a gas and so surely it goes everywhere. It's not directional surely?

Set up last night, got a nice polar alignment and star alignment. Focused and found my chosen target. Started taking subs and went indoors to watch some TV while my lovely data accumulated. 1 hour later I went back to check everything was still ok and the front of my SCT was completely fogged up with condensation!! Un-mounted the scope, brought it in the house and blew a cool air fan over the front for 20 mins. Soon it was crystal clear. Set it all up again and resumed taking subs (assuming that the weather had probably now cooled down enough to have dropped all its dew). 1 hour later completely fogged up again! Now I know why all you guys have dew heaters! Lesson no. 27 learned 😞

M13 and M57 taken last night with a 20cm SCT f/6.3, 15 sec subs

Thanks Vlaiv. Here is how it turned out

Ok, so I deleted all those pesky JPGs and re-ran DSS. Now the autosave.TIF is no longer purple. But it looks like there is nothing to move the left hand arrow to the data. It's already there. So what do I do now?

I just discovered that I had a full set of JPG copies in my lights folder which I uploaded to DSS!! My Canon DSLR shoots a JPG copy of every RAW for some reason and it looks like I forgot to delete them! I'm going to start the whole process again

Thanks Vlaiv Here it is after some further fiddling with levels and gamma. But I will do as you suggest and check the lights for clouds (for some reason, Photoshop won't let me save the TIFF as a JPG, so in order to post here I had to screen grab it with snipping tool!)

Ok, so this is how it looks after adjusting the left hand arrow to the start of the data in each channel separately. Definitely better, but I am not sure if I have captured quite enough light in my original light frames, maybe? I limited my exposures to 15 sec as I am only using an EQ6R Pro with no guiding and was concerned about getting trails. Could I afford to take longer exposures do you think?

Thanks everyone. I'll try this and report back. Yes, RAW images

do you mean the levels histogram? It looks like this at the moment. What should I fiddle with? and where's all that purple come from?

I just had a go at registering and stacking a bunch of images I took last night of M13 with a 20cm SCT f/6.3 70 light frames (15 sec at ISO1600) 15 dark frames 18 bias frames 30 flat frames I had to set the star detection threshold right at the bottom end (2%) to find enough stars (it suddenly went from finding none to finding 450) But the final autosave.TIF looks purple for some reason. Here's a screenshot of it in Photoshop. I also attach one of the light frames so you can see I did actually capture something