Manners2020

I've never heard of astropixel  before. I'll  have a look at that. Thx.

That is useful  actually.  I've oo'd and arghed  for a long time over paying for a software and the subscription  has put me off ps, the price has put me off pix. Startools  I have tried but it was ever so slow on my laptop.  I did try a German one once but I forget the name, it was pretty decent but I dont recall any option for English so I was winging it more so than I normally do.  I think I'll  wait until I need to replace the laptop and try startools again. 60 Canadian is more than reasonable  in my oppinion.   Thanks for the input everyone.  I'm going to post a wider view of the trifid now which for the 12 minutes or so that was spent capturing  it I'm pretty pleased with... but for the sky.  Is this type of sky colour even fixable with more suitable editing  software or is this just the short amount of exposure , skyglow and my lack of understanding  of histograms ect? 

Right. Photoshop is something I've  been flirting with the idea of  actually.  

I'll have a look at that. Does it need as much computing power as startools?

No, just gimp so far. 

The darks and flats were in there. Probably  not enough though and my flats were ones I used from a week before. I wasn't convinced they were doing a good job. Heres a question about flats actually. ... so the focus is supposed to be the same as the lights but does that mean actual focus or the distance  of the image train being in the exact position  to the corrector  plate as the lights.. you know with focus shifting slightly and the rest of it?

That's  the plan but it will have to be a different  time of year.  It was literally  inches above my neighbors  roof.   I always get a much harder sky colour tobdeal with when I'm shooting to close to houses.  Thanks though , that's the most detail I've ever had from that one.

Whirlpool, trifid  and eagle.  Rare night with a visible sky last night.  All three were 72×10 seconds exposures with 20 dark and 20 light frames.  First time I've seen these two nebulas  so I was thrilled to catch them. 9.25 nexstar evolution @f 6.3 with an asi294 mc.

These are rough and rushed but ive been having some sharpcap  issues of late. I've only been getting a few exposures  before stacking going south. Re installed it now and it looks updated and ive watched a couple of vids and learned a few things about the histogram.  Hopefully I'll  be having another crack at these soon.  M104 was the most I've managed at about 9 minutes worth of 20 second exposures, thec rest were just a few exposures each. No darks or flats on any due to my issues. Nexstar evolution 9.25 @6.3  with an asi294 mc.  I would say processed but it was more of a butchering in gimp and snapseed.  

I love these wide field shots.?

I like pc  expess  for noise reduction  and snap seed for the levels. I've still a lot to learn with gimp.

This image is why I didn't  bother initially. I thought I'd  never get rid of all that red.

Think this is my favourite  so far.  28x30 sec exposures  live stacked on sharpcap.  I cant remember  if I used darks for this as I've just found the data I did a bit ago that I thought was useless at the time.  Wo72mm megrez,  asi294, nexstar evolution mount,  0.8 reducer. Tweaked in gimp , snap seed and pc  express.

Cheers jim, I've flirted with the idea of an eq  mount from time to time but I really like the ease of my set up and where I can set it up.  I dont think I'll ever bother to be honest. If I decide in the future I want to spend a couple more k on equipment  I think I'd rather spend it on one of those rasa  8's than a mount.  That's  my dream scope right now.  And yes the camera's  are amazing right now, it'll  be interesting  to see what's out there in a few years.

Cheated a bit on this . I used a healing tool for the core in free photo shop app on android.  It was blinding.  28 30 second exposures , 20 darks and flats.  Wo72mm megrez,  asi294mc, nexstar evolution  mount  . Stacked and stretched in sharpcap,  tweaked in gimp and photoshop  express. 

Bloody hell that dob. Thanks for the info. I'll maybe make a mock one up out of card and see what the clearance might be.

Oh and this eaa  tool, is that to put out there or strictly  for your own use?

Thanks  , I was just wondering  mainly about clearance.  The mount I have is the evolution  mount.  I can only get about 63° with the sct when the camera is on ect, which is good enough for me. I'm guessing  the Newt is quite a lot heavier  to the rear which would allow me to push it forward quite a bit without it being too much front heavy? I've searched high and low online for a picture of my mount with a newt on and cant find one. 

On 23/10/2014 at 10:22, Martin Meredith said:

Great idea. Everything I do is in alt-az, mainly in short exposures for "near-live" observing (none of these are for hanging in your gallery). All taken with the SX Lodestar-C guide camera using SW Quattro CF 8" f/4, no filters unless mentioned nor coma correctors. All are saved screenshots from Paul81's wonderful free LodestarLive application with no further manipulation. I mainly post on the video forum but these are as yet unseen shots.

BTW alt-az induced field rotation is not much of an issue with live stacking + shortish subs. I mainly limit myself to 60s with my 80mm f/6 refractor and 30s with the Quattro.

NGC 6946 Fireworks galaxy 1 x 30s

M1 Crab (rather low at 23 deg at the time) 4 x 30s

M101 4 x 30s

B33 Horsehead + NGC2023 (stupidly low at 16 deg and with out-of-date darks but irresistible and a proof that I'm mainly an observer and not an imager  ) 4 x 30s

Part of the Veil with O-III filter 3 x 30s

NGC7635 Bubble 4 x 30s

M27 1 x 30s

Cheers

Martin

Are you still active on here Martin? I see this is from a good fee years back but I've often wondered about the quattro  on an  alt/alz mount. Wouldn't  mind picking your brains if you're  still here.

That's the only time I've seen colour in one of my galaxy's.  

Oh yes,  I should give startools another try. I followed a almost three hour tutorial  twice but without  calibration files. 

Just now, Manners2020 said:

Thanks for that image, also glad to hear about the focus .

Is that with startools?

24 minutes ago, Filroden said:

I've never noticed any issues with my flats due to focus changes. On closer inspection, maybe the gradients are all pollution related rather than flats? It's just that each image appears to be vignetting.

Here's a crop with the gradient removal and saturation boost. Pre-processed low res JPG isn't the best starting point but it should show you there is colour hidden in there.

Thanks for that image, also glad to hear about the focus .

12 minutes ago, The Admiral said:

Or, you could leave it on the table and take the flats by putting a laptop/tablet, displaying a plain white screen, directly in front of the objective. I think you'd still need to diffuse it though, and don't have the screen brightness too high so that you can get a reasonably long exposure (i.e. tenths of a second rather than hundredths or less).

Those images are a good start! But galaxies are hard in the sense that they are generally small in the FoV, which makes them susceptible to tracking errors and field rotation, which will smear their tiny details.

Ian

Just a quick one on the histogram.  I've been adjusting exposure and gain until sharpcap gives me a green ok.  The image for the flats is always a pale muggy brown .  Should I maybe not be paying too much attention to the ok and more on the actual  histogram? 

1 hour ago, Filroden said:

I have to disagree. I took a closer look at your jpg of M33. After a quick background gradient removal to remove the worst of the vignetting/light pollution, I only needed to do two boosts to the saturation to see a pale yellow core and lovely blue arms.

I think your problem is not the data but the calibration. I can't stress enough how important flats are to an image. I was terrified by them when I started. However, they are actually really simple to take and can be done the next day if you are careful. Here's what I do:

- When I tear down the kit for the night I am careful to remove the scope/camera as a single unit (leaving it at its last focused position) and I take it all inside and leave it on the dining room table

- The next morning I set up the tripod/mount again and put the scope/camera back on the mount carefully (so as not to disturb any dust)

- I point the scope at any bright area of sky (cloudless or uniform cloud both work)

- I fold about 4 pieces of white A4 paper of the end of the scope to reduce the sky brightness and act as a natural diffuser (white cotton also works but I like paper as I can fold it above and below the scope so it almost holds itself to the scope)

- I then take flats, exposing them until they peak at about 50% of the histogram - typical exposures for me are about 0.1 seconds and I take 25 for each filter

- Having captured the flats I bring it all back inside (you could do it outside but why be cold?)

- I then take corresponding dark frames of the same exposure lengths as the flats (again, 25 flat-darks should be ok) [Note: for DSLRs you might skip darks and only use bias to subtract]

The flats and flat-darks can then be added into your processing software of choice along with your darks and lights

Voila. a much better starting point to begin processing.

I have wondered if my flats have been doing anything to be honest. I've been doing them with a t shirt and white light on a tablet straight after my darks which I've been doing straight after focussing.  I've been doing it that way because I've convinced myself the focus would be out if I left it until the next day eith the change in temp.  The darks I can see what good they are doing but I wouldn't  recognize if my flats were or not . I'll try what you suggest with the paper and sky next time. And I've just had a thought. If my focus tube is in the exact position but focus is off due to temp change , would that still count as the same focus for the flats? Also would you mind posting that pic of my image you tweaked, I'd live to see the colour in it. Thx for the pointers.