The "No EQ" DSO Challenge!

[The Admiral]

Yes! 

Ian

[Herzy]

Did you have gradients to deal with? I had trouble processing this target because I couldn't differentiate between noise and small gas structure. There are so many small gas clouds in the galaxy that look like noise. I would have gradients with heavy noise on one side and smooth on the other so I couldn't get anything out of it.

[Filroden]

14 minutes ago, Herzy said:

Did you have gradients to deal with? I had trouble processing this target because I couldn't differentiate between noise and small gas structure. There are so many small gas clouds in the galaxy that look like noise. I would have gradients with heavy noise on one side and smooth on the other so I couldn't get anything out of it.

I had a broad gradient running from bottom of image to the top, plus some vignetting because I didn't use flats, which AutomaticBackgroundExtraction took care of. I also had a fairly large dust bunny just to the south of the galaxy and about 25% of its size. I modelled this carefully selecting many points in and just outside the dark area avoiding selecting anything in or near the galaxy and DynamicBackgroundExtractor took care of that after two applications.

Otherwise, I was fairly blunt with noise removal in the colour channels, and applied MultiscaleLinearTransform noise reduction to first 5 wavelets (in decreasing strength) before stretching and then, with a lum mask, a little more MLT after stretching with some TGVDenoise thrown in. I also (with use of galaxy and star masks) applied sharpening and unsharp to the galaxy to enhance the finer details. I enhanced the contrast with some HDRMultiscaleTransform.

I still have a lot to learn in terms of processing - my masks are still very "wild" and could be created with much more refinement. I also still haven't wrapped my head around deconvolution (though at least now I can use it) or LocalHistorgramTransformation (which I didn't use).

P.S. Should have added, if you check the original version I posted (not the black clipped version I did in Lightroom) and zoom right in (you may have to download the image), you can see there is some very fine noise in the galaxy but nothing that detracts from the star forming regions or areas of nebula (which are much easier to see zoomed in).

Edited October 3, 2016 by Filroden

[Nigel G]

35 minutes ago, Filroden said:

Like so?

 

Very nice Ken, that's a vast improvement in details and great colours, I'm impressed. 

That's probably the best image I have seen from an Alt-Az mount.  I wonder how sharp a nebula will be.

Well done. 

Nige.

[Filroden]

3 minutes ago, Nigel G said:

Very nice Ken, that's a vast improvement in details and great colours, I'm impressed. 

That's probably the best image I have seen from an Alt-Az mount.  I wonder how sharp a nebula will be.

Well done. 

Nige.

I can't really image the California Nebula until around 23:00 and I can only image the Soul before about 22:00 (the Heart is too big even for a two panel mosaic). The Pacman is already too high. The real test will be in a month or so when I can get my scope onto the Rosette, Flame, HH and Orion nebulae.

The weather here is nice at the moment but the forecast is saying low cloud cover moving in around 20:00, but tomorrow is still looking promising. I have the scope still set up from last night and sat on the dining room table so it won't take me long to set up if I get another dark night.

[Filroden]

Okay, one final version and I will stop tweaking (at least for today). I took the original image into Photoshop, cropped it and then rescaled the image to fit approx. A3 at 300dpi. I applied a little vibrance and a small S adjustment curve to enhance the contrast. I'm much happier with this than the linear stretch I applied in Lightroom which I think just clipped detail rather than enhanced contrast.

Tiff attached.

M33_20161002_v3.tif

[The Admiral]

33 minutes ago, Filroden said:

Okay, one final version and I will stop tweaking (at least for today). I took the original image into Photoshop, cropped it and then rescaled the image to fit approx. A3 at 300dpi. I applied a little vibrance and a small S adjustment curve to enhance the contrast. I'm much happier with this than the linear stretch I applied in Lightroom which I think just clipped detail rather than enhanced contrast.

Better still Ken, well done! A little brighter, which brings out the nebulous bits somewhat better. Given that you've scaled it to 300dpi on A3, does that mean that it'll end up on your wall?

Ian

[Filroden]

7 minutes ago, The Admiral said:

Better still Ken, well done! A little brighter, which brings out the nebulous bits somewhat better. Given that you've scaled it to 300dpi on A3, does that mean that it'll end up on your wall?

Ian

I'm thinking about it though I prefer the wispiness of M45. I know a good printer in East London but I'd like to see if I can find one locally that can handle astro images (shades of black are much harder to print!). I'm going to put it and a couple of other images onto a memory stick and test them at A4 and A3 to see how they work. Alternatively, I might see about A5 and create something with a few images (and maybe a little text) too. Another project for a cloudy night!

[SteveNickolls]

The gear in operation last night. Look at that night sky, the perfect shade of muddy coffee.

Good luck everyone who is imaging tonight.

Cheers,
Steve

[Herzy]

Light pollution is just awful. That picture of the light pollution is so ugly yet that is the case for most of the population.

[happy-kat]

I've been looking back at the image graph with direction, altitude and duration and I though that generally the higher the altitude the shorter the duration and even shorter in N / S but these recent targets have been high and getting 45s and don't seem impacted by focal length either. Yes it is clear but not able to get out side tonight.

[SteveNickolls]

42 minutes ago, happy-kat said:

I've been looking back at the image graph with direction, altitude and duration and I though that generally the higher the altitude the shorter the duration and even shorter in N / S but these recent targets have been high and getting 45s and don't seem impacted by focal length either. Yes it is clear but not able to get out side tonight.

Interesting observation, I've been following the guidance charts on avoiding field rotation in Joe Ashley's book as the maths is way beyond me. I guess there's some leeway in the figures and having a shorter FL wide view as from a piggybacked DSLR ought to help out somewhat too. I tend to round my exposure times down, maybe I ought to try increasing them a shade :-)

Sorry to hear you can't get out to image tonight. The weather forecast is looking generally good this week so another opportunity should come your way.

Cheers,
Steve

[Nigel G]

Last nights efforts.

I'm not sure if I have something set wrong but I'm having serious trouble with colours, after stacking and Developing in ST my image was bright green, same as a mask green , in fact just for the hell of it I chose mask and could hardly see the mask green. To get some sort of colour is a proper task. No matter how hard I try I can't get any white stars, just blue, green, red or purple.

I thought I'd have ago at the Veil nebula with my 210mm lens. After all the delays of last night I got around 1h 40m of 60 and 90 second subs. along with 68 dark, 30 flat and bias. ( had to create whole new batch for wifes new camera ) As the battery on the camera was running low I couldn't resist a quick snap at M45, the lens had just started to collect a little dew on so I grabbed 9 60s subs and stacked them too with 9 dark 9 flat and bias. not bad for 9 minutes exp time.

Theres more in the first image than I was expecting, in the last 15 minutes light dew had started settling. I wonder what this would be like with a cooled mono CCD.

 

Cheers

Nige.

[Herzy]

Both images are slightly out of focus. Other than that, it's a good image.

[Nigel G]

1 minute ago, Herzy said:

Both images are slightly out of focus. Other than that, it's a good image.

That might be due to the dew on the lens. I kept checking and noticed it the last 15 minutes or so.

[Filroden]

9 hours ago, Nigel G said:

Last nights efforts.

I'm not sure if I have something set wrong but I'm having serious trouble with colours, after stacking and Developing in ST my image was bright green, same as a mask green , in fact just for the hell of it I chose mask and could hardly see the mask green. To get some sort of colour is a proper task. No matter how hard I try I can't get any white stars, just blue, green, red or purple.

I thought I'd have ago at the Veil nebula with my 210mm lens. After all the delays of last night I got around 1h 40m of 60 and 90 second subs. along with 68 dark, 30 flat and bias. ( had to create whole new batch for wifes new camera ) As the battery on the camera was running low I couldn't resist a quick snap at M45, the lens had just started to collect a little dew on so I grabbed 9 60s subs and stacked them too with 9 dark 9 flat and bias. not bad for 9 minutes exp time.

Theres more in the first image than I was expecting, in the last 15 minutes light dew had started settling. I wonder what this would be like with a cooled mono CCD.

 

 

Cheers

Nige.

Hi Nige

This is a strange one. I can clearly see the green in the first image but the same effect is missing from the second. Did you change some of your processing steps between the two images?

One thing that jumps out at me in the first image is that it is the cores of the stars which are green. Their halos all seem to carry the correct colours (reds, whites and yellows). It's as if the cores are over-exposed and some process you've done in StarTools is highlighting/masking the star cores and affecting just them?

I had a play with the jpeg in both PixInsight and Photoshop. I couldn't do much with the star colours - I could reduce the green but I couldn't re-tone the stars. However, it has a great little tool that reduces star sizes and when I ran that, the Veil lifted! A little brightening in Photoshop later and ...

That's a lot of Veil you've captured there. Nicely done. I think it's quite a tough target even with long exposures.

One more thing springs to mind (and it's been mentioned a few times in the thread), could the colour issue be something to do with debayering and therefore to do with that initial setting in StarTools? Alternatively, is it a setting in DSS?

Edited October 4, 2016 by Filroden

[Filroden]

I have two projects for the daylight hours today:

1) Squeeze an extra 5-10 degrees of altitude out of my mount. Moving to the new camera really extended my imaging train and it has reduced how high I can image. I think I can get more altitude if I turn the camera upside down as it moves the bulk of the filter wheel away from the mount. I'm also going to see if I can move the scope further up, though its dove bar is very short. The DSLR was small enough that it could almost clear underneath the scope and allowed me to get to at least 75 altitude. Now I's scared to go near 65, which is really limiting my imaging options. My mount was definitely not designed with imaging in mind!

2) Take an all-sky panorama to load into SkySafari so I can better estimate when targets are clearing the houses/street lights. I hadn't realised how little sky I can actually see when I bought the house. It initially looked like I could see half the sky from the patio but the height of the houses plus the three street lights leaves me a small cone from roughly NE to SE and from 20 to 60 altitude (with the ideal imaging altitude being around 40 to clear the light pollution but still stay low enough to reduce rotation)  I could move the scope to the end of the garden and recover a little of the western sky but that relies on my first project being successful and also means I have to leave the warmth of the kitchen and sit in the garden (and means trailing an extension the length of the garden).

 

Update: regardless of where I move the dove bar, the highest I can go without camera contact is 71 degrees. If I don't rotate the camera/filter wheel that reduces to 66 degrees. 

Edited October 4, 2016 by Filroden
Update on progress

[happy-kat]

Given rotation and everything moves around eventually I guess that's workable

[Filroden]

2 hours ago, happy-kat said:

Given rotation and everything moves around eventually I guess that's workable

I'm just impatient. It currently puts Pacman, Iris, Veil, NAN, etc out of reach until next summer unless I carry the kit to another site (and that means figuring out battery power). I've probably got a limited window on Soul so I might try and frame it horizontally and see if I can't fix the issues I had last week. 

Update: just checked and it looks like both Pacman and Gamma Cass are within my altitude limit for about an hour.

Edited October 4, 2016 by Filroden

[happy-kat]

I have a balance issue, never thought to check before but the 85mm lens is very front heavy.

I've got spare camera fixings from doing the barndoor project so might be able to fabricate something... And I need a different step down ring for the lp filler for the pancake lens so going to get that ordered as that lens balances fine.

 

[parallaxerr]

Hi everyone,

Well, I've just finished reading the contents of this thread and I must say I'm thoroughly impressed with the quality of images here! I never thought it would be possible to creat images like these with the sort of equipment being used, I have obviously been brainwashed by the EQ only crowd

I was pointed in this direction when @happy-kat put me onto @The Admiral after disussing something about my Nexstar SE mount in another thread (I forget exactly what, now). Having spoken to Ian via PM I found myself being gently encouraged to have a go at Alt/Az imaging.

So...this is to say hello and I hope to join the party soon, as I've placed an order for all necessary bits to get my camera on the end of a scope (highlighted blue below)!

My setup will consist of:

• Celestron Nexstar SE 6/8 mount
• William Optics Zenith Star 66SD doublet Apo
• Baader SCT to 2" click-lock
• Baader Multi Purpose Coma Corrector (proven to work rather nicely with the 66SD here - http://www.stark-labs.com/craig/WO66SD/WO66SD.html)
• Nikon T-ring
• Nikon D3200 DSLR

Here's to hopefully contributing my first images before too long and quizzing you all on exactly where I'm going wrong! Looking forward to this little foray into imaging!

Jon

[Filroden]

19 minutes ago, parallaxerr said:

Hi everyone,

Well, I've just finished reading the contents of this thread and I must say I'm thoroughly impressed with the quality of images here! I never thought it would be possible to creat images like these with the sort of equipment being used, I have obviously been brainwashed by the EQ only crowd

I was pointed in this direction when @happy-kat put me onto @The Admiral after disussing something about my Nexstar SE mount in another thread (I forget exactly what, now). Having spoken to Ian via PM I found myself being gently encouraged to have a go at Alt/Az imaging.

So...this is to say hello and I hope to join the party soon, as I've placed an order for all necessary bits to get my camera on the end of a scope (highlighted blue below)!

My setup will consist of:

• Celestron Nexstar SE 6/8 mount
• William Optics Zenith Star 66SD doublet Apo
• Baader SCT to 2" click-lock
• Baader Multi Purpose Coma Corrector (proven to work rather nicely with the 66SD here - http://www.stark-labs.com/craig/WO66SD/WO66SD.html)
• Nikon T-ring
• Nikon D3200 DSLR

Here's to hopefully contributing my first images before too long and quizzing you all on exactly where I'm going wrong! Looking forward to this little foray into imaging!

Jon

Welcome Jon. That WO66SD should give a nice field of view. Can't wait to see your results. Do you have some targets in mind already?

[parallaxerr]

Just now, Filroden said:

Welcome Jon. That WO66SD should give a nice field of view. Can't wait to see your results. Do you have some targets in mind already?

Thanks for the welcome, as it happens I just punched the scope and camera data into FOV calculator and got this...

M31 is nicely positioned for me at the moment but I want to learn to walk before I can run! The double cluster in Perseus is one of my favourite visual objects and nicely positioned too so should be a good target to start with. Being brighter I hope to get away with less/shorter subs and test my hand at DSS.

[Herzy]

*deleted* 

I misread the post and thought he hadn't bought anything yet. I can't figure out how to delete the post so just ignore this.

Edited October 4, 2016 by Herzy

[parallaxerr]

2 minutes ago, Herzy said:

Sorry to kill your fun, but you don't quite have your priorities straight. The images in this thread are great, but there is a limit to what you can do with an alt/az mount. While the limit is still pretty high up, and you may be able to be satisfied with your images for a long time, if you decide to really get in the hobby a mount like this won't get the job done long-term. 

As most astrophotographers will tell you, 50% or more of your budget should go towards your mount. Your mount is the most important piece. It is really important because even 1/1000 of an inch of error in tracking the sky will give you trails. It's hard to imagine how precise you have to be. If the mount is so important, I wouldn't advise you to buy something that won't last you long-term. I'm sorry, but that's the truth.

I use to be an alt/az user so I still read and participate in this thread as I know the struggles of this kind of mount. I believe that this thread should be used as encouragement for those who ALREADY have an alt/az mount to not give up or be disheartened. It should NOT be a thread advising people to get one over an EQ mount (unless your planning on wide field work).

Again, I'm not saying that you won't make cool images with a setup like that. I'm just saying that if you have the choice right now to choose between an EQ mount or an alt-az, an EQ is the way to go. 

I DO already have an Alt/Az - the Nexstar SE. That's the point, I'm just having a go with what I've got!