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JGM1971

The "No EQ" DSO Challenge!

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Both M56 and M57 should be able to take very long exposures before you see rotation as they are very low and moving round to almost due East. I might give them a shot tonight and see how far I can push it. The killer for me is light pollution which limits my total exposure. I think my peaks were almost 2/3rds across the histogram after 45 seconds at that altitude. I might drop down to ISO800 or even 400 just to test.

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Wuppmupp.  Very nice, you've picked up the nebulosity around the star in Pleiades, both good clear images. 

Well worth sharing. 

Look forward to seeing some more. 

Nige.

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Hi Ken,

Lovely image of M5 you have :-) Sorry you had so much trouble getting any decent frames of M13. I'm intrigued at your 9.25" SCT and what it can do.

Good luck imaging tonight.

Cheers,
Steve

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7 minutes ago, Filroden said:

Both M56 and M57 should be able to take very long exposures before you see rotation as they are very low and moving round to almost due East. I might give them a shot tonight and see how far I can push it. The killer for me is light pollution which limits my total exposure. I think my peaks were almost 2/3rds across the histogram after 45 seconds at that altitude. I might drop down to ISO800 or even 400 just to test.

Hi Ken,

Yet I forgot to mention light pollution, it's bad here you can usually see stars to Mag 4.3. I made a series of exposures of the night sky on a moonless night from 5 to 80 seconds, it resembles a colour chart from Dulux in their coffee range :-) Unless your frames are whited out you should still be able to pick out signal fram noise but it will degrade the detail. Wouldn't it be great to have darker skies.

Here's the colour chart!

Canon EOS 600D 5to80s.pdf

Cheers,
Steve

Edited by SteveNickolls
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Could you paint my fence in the 70 sec exposure?

I think I have similar levels, at least to the North (Bristol 20 miles) and West (Cardiff 15 miles) not to mention Weston-super-Mare between them at 7 miles. That said, I downloaded the sky quality meter for my iPhone and it claims I have a 19.65 sky or 5.6 NELM. I can barely see 4 stars in Ursa Minor so I think my phone is having a laugh!

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1 hour ago, The Admiral said:

Why do you think the focus is out Nige, they look pretty sharp to me? I think you've done pretty well there, they are after all very small galaxies. Was there a thin veil of cirrus cloud whilst you were imaging? There was here, and I didn't bother to try.

Ian

I had to change battery's after about 40 frames and I moved the camera slightly, I didn't want to move the scope so I couldn't re focus on anything , atm I'm using Jupiter's moons for focusing, there was nothing in the frame to do a live view focus. All very faint, and yes there was a little high level cloud for the first 45 mins so I tried to use that time taking darks, there was a whisper of cloud from time to time after midnight. 

Nige.

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5 minutes ago, Filroden said:

Could you paint my fence in the 70 sec exposure?

 

He, he a pleasure Ken you are obviously a man of great taste, both of coffee and paint.

 

Cheers,
Steve

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2 minutes ago, SteveNickolls said:

He, he a pleasure Ken you are obviously a man of great taste, both of coffee and paint.

I prefer my coffee like my skies...black. Unfortunately all I get is milky (and not the way kind)

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40 minutes ago, Nigel G said:

I had to change battery's after about 40 frames and I moved the camera slightly, I didn't want to move the scope so I couldn't re focus on anything , atm I'm using Jupiter's moons for focusing, there was nothing in the frame to do a live view focus. All very faint, and yes there was a little high level cloud for the first 45 mins so I tried to use that time taking darks, there was a whisper of cloud from time to time after midnight. 

Nige.

I do a 2-star alignment when setting up, and I generally focus on the second star. I admit though, that my 'scope seems fairly stable to focus drift with time, which I guess might not be the case with a Newt.

Ian

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27 minutes ago, The Admiral said:

I do a 2-star alignment when setting up, and I generally focus on the second star. I admit though, that my 'scope seems fairly stable to focus drift with time, which I guess might not be the case with a Newt.

Ian

I don't generally have a problem with focus, I think it's just an accident when changing the battery. I focus on Jupiter's moons as I gives me a quick look at the giant ☺

Another go tonight, hopefully a bit better seeing. 

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Well I removed an extra 30 fames and left out the flats, there's a lot of stacking artefacts as I don't want to crop out the tiny fuzzys 

It needs a clearer night for it. Can't do much to this. 

I counted 14 possible galaxy's though ?

Nige.

PSX_20160504_194611.jpg

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18 hours ago, SteveNickolls said:

You've some really nice stars there Wappmupp and a great first try. I think globular clusters and even open clusters by their nature of being points of light can be well imaged with not so many exposures. Sometime I'd like to improve my stars as the telescope I currently have suffers from 'star bloat' a lot but that's ok while I'm learning the ropes. Good luck in your future imaging sessions.

Cheers,
Steve

Thanks! :smiley: Yeah, I find globular clusters great to image while I'm still learning the basics. It seems much easier to make them pop in an image than say a much fainter nebula.

17 hours ago, The Admiral said:

You shouldn't be bashful, you've made a great start with those. Both have a lot of detail and M45 is showing some nebulosity, which you might be able to enhance further. My only criticism is that on my monitor they both look a bit green; the nebulosity in M45 should if anything be blue. That should be an easy fix in PS. With a 200P you should be able to hoover up the photons at a far greater rate than with my 102mm refractor.

Ian

Thank you! :smiley: You're right about the green. I really didn't notice that before you said anything. I must have been way too eager to upload :tongue: I'll see what I can do about it.

17 hours ago, Filroden said:

Both are great. I cannot believe how clear the nebulosity around M4 is with so few subs. I'm so jealous. I must have taken 50-100 subs of M45 and not a whisper. Well done! Likewise, you've got the core of M13 captured - you can see the cross of the propellor (I always think of Star Wars and crossed light sabres rather than a blimp coming towards me with a propellor at its nose).

You must have very dark skies? That will really help you capture detail with short subs. 

Hehe, thanks! :grin: I was honestly quite suprised myself to see any kind of nebulosity at all. My skies are pretty dark but I'm only about a mile outside of town so light pollution is still somewhat of an issue. It's atleast dark enough to hint at the Milky Way going across the sky. I'm gonna try and find a nice spot further out of town in the future. We have almost unpolluted skies with a 30-40 min drive out.

 

16 hours ago, Nigel G said:

Wuppmupp.  Very nice, you've picked up the nebulosity around the star in Pleiades, both good clear images. 

Well worth sharing. 

Look forward to seeing some more. 

Nige.

Thank you! :smiley:

//Anton

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As dusk approached last night I wondered if it would be worth imaging, as there was so much high cloud around. But by the time I and the twilight were ready it didn't look too bad so I thought I'd push on with Makarian's Chain. It meant placing my 'scope in a slightly different position in the garden so that I'd get long enough on it. All going smoothly, until near the end of my first batch of 60 x 30s subs when I realised that I had only roughly focused whilst aligning. Doh! A wasted 1/2 hour which meant a really late finish (for me). No stars in the FoV to focus on, so I slewed to Jupiter (clearly a Nige moment!) and focused on its moons, then back to Makarian. In the end I had 123 frames for DSS to munch on, of which it decided to stack 91, so in all about 45 minutes total exposure. Not long enough really, and it shows in the noise levels. All things considered, I'm quite please with the final result. NGC4477 looks a bit odd because it's in a stacking artefact and so doesn't benefit from all the subs during stacking, hence the noise. M84 is also a bit noisy, but the bottom RH corner generally shows rather more noise. I suspect the darks aren't doing much good there.

Autosave set1&2 stk91 ST2bin50%  LR1.jpg

 

91 lights stacked in DSS, along with 51 darks, 51 bias, and 50 flats, processed in Star Tools, and polished in Lightroom. Fuji X-T1 at 1600ASA through an Altair 102mm f/7 Super ED, all mounted on a Nexstar 6/8SE mount, 4th May 2016.

Ian

 

Edited by The Admiral
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51 minutes ago, The Admiral said:

As dusk approached last night I wondered if it would be worth imaging, as there was so much high cloud around. But by the time I and the twilight were ready it didn't look too bad so I thought I'd push on with Makarian's Chain. It meant placing my 'scope in a slightly different position in the garden so that I'd get long enough on it. All going smoothly, until near the end of my first batch of 60 x 30s subs when I realised that I had only roughly focused whilst aligning. Doh! A wasted 1/2 hour which meant a really late finish (for me). No stars in the FoV to focus on, so I slewed to Jupiter (clearly a Nige moment!) and focused on its moons, then back to Makarian. In the end I had 123 frames for DSS to munch on, of which it decided to stack 91, so in all about 45 minutes total exposure. Not long enough really, and it shows in the noise levels. All things considered, I'm quite please with the final result. NGC4477 looks a bit odd because it's in a stacking artefact and so doesn't benefit from all the subs during stacking, hence the noise. M84 is also a bit noisy, but the bottom RH corner generally shows rather more noise. I suspect the darks aren't doing much good there.

Autosave set1&2 stk91 ST2bin50%  LR1.jpg

 

91 lights stacked in DSS, along with 51 darks, 51 bias, and 50 flats, processed in Star Tools, and polished in Lightroom. Fuji X-T1 at 1600ASA through an Altair 102mm f/7 Super ED, all mounted on a Nexstar 6/8SE mount, 4th May 2016.

Ian

 

Great picture I can't wait to see the image once you've got more data! This is my next target.

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That's the one, great effort Ian, Well done. 

Nige.

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Thank you Nige and Herzy. Clear Outside shows it clouding up here around 23.00, and whether I'd want to go back to it I don't know. Not much else around that I can see though!

Ian

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Hi Ian,

Well done you should be proud of that image, I compared it to one on Wiki and yours is better! You have everything in. Are you proposing to add more frames another night? What do you use Lightroom specifically for can I ask?

Cheers,
Steve

Edited by SteveNickolls

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That's very kind of you to say so Steve. I don't know about adding more frames, I need to balance up the suffering for my art (i.e. lack of bedtime) with the benefits of (possibly) improving the image. In other words, how much more would I have to do to make a significant improvement, and whether it's worth it.

I'm finding that I use Lightroom more now since Nige suggested using Photoshop Express on my M64 image. I use the sharpen and noise reduction functions, and sometimes clarity, as I find it seems to smooth the bits that need smoothing yet leaves the detail there. I also use it for producing the files suitable for uploading to the site.

Cheers - Ian

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(removed: accidentally double-posted.)

Edited by Herzy

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A bit of a tough session last night keeping only 150 frames of about 350, deleted so many subs cause of star trails,  not a lot of breeze, the mount was being lazy last night. 

Finally finished at 2.30am after a quick video capture of Saturn. 

I'm finding it a bit challenging capturing and processing these faint fuzzys,  I might try shorter exposures, also different exposure lengths in same stack. I was reading about adding short exposure to get core details and longer to get wide detail. Worth a go I think.

Targets, The Sunflower galaxy and M88 M91. Sunflower 60x30s 1600 iso.  M's 90 x 30s.  Both 40 dark 12 flat 50 bias.DSS & StarTools. 

Nige.

PSX_20160505_150537.jpgPSX_20160505_123454.jpg

 

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Some great new images.

Ian with your last target and so close to the frame edge why not consider doing a two pane mosaic?

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I never get time to image with school. I'm limited to imaging only on clear nights on weekends. With the weather over here that's like 1 clear night a month. :(

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3 minutes ago, happy-kat said:

Some great new images.

Ian with your last target and so close to the frame edge why not consider doing a two pane mosaic?

 

I think I'd rather buy a focal reducer! I'm not good with late nights. But it's a possibility.

Ian

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2 minutes ago, Herzy said:

I never get time to image with school. I'm limited to imaging only on clear nights on weekends. With the weather over here that's like 1 clear night a month. :(

Well believe me it's not much better than that here, even though I'm retired!

Ian

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49 minutes ago, Nigel G said:

A bit of a tough session last night keeping only 150 frames of about 350, deleted so many subs cause of star trails,  not a lot of breeze, the mount was being lazy last night. 

Finally finished at 2.30am after a quick video capture of Saturn. 

I'm finding it a bit challenging capturing and processing these faint fuzzys,  I might try shorter exposures, also different exposure lengths in same stack. I was reading about adding short exposure to get core details and longer to get wide detail. Worth a go I think.

Targets, The Sunflower galaxy and M88 M91. Sunflower 60x30s 1600 iso.  M's 90 x 30s.  Both 40 dark 12 flat 50 bias.DSS & StarTools. 

Nige.

 

You've done well there considering you've had limited exposure. I've noticed that some of my frames have significant streaking, whereas other have none. I guess it's the way the mount zig-zags in jerks, and it depends on whether you're exposing during one of its zigs or zags, not to mention where the mount is pointing at the time. In that respect, shorter subs may help I suppose. I'm guessing here, but as Alt-Az mounts are intended for visual there probably isn't much incentive for manufacturers to adopt some form of smooth drive, so that both axes are driven continuously at the correct, and variable rates. May be it just needs much finer steps, much the same way that EQ mounts are driven. It would be interesting to know if the Skywatcher AZ-EQ mounts have a smoother movement, given that they use the same drives irrespective of whether they are in EQ or AZ mode.

For some reason I've regarded M63 as being a difficult object, not sure why. Having only 1/2 hour's exposure sure makes life difficult. I've always thought that the suggestion of using shorter sub lengths in the same stack really only applied when the standard sub length, reckoned in many minutes, causes the bright bits to overexpose, so the shorter exposures 'fill in the gaps'. With the short sub lengths that we use, I do wonder if that is a significant problem (with the exception of stars perhaps).

Ian

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