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JGM1971

The "No EQ" DSO Challenge!

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Well, I think I've no Heart but I might have a Soul. Just spent best part of the day integrating and re-integrating 60x30s shots of both Heart and Soul Nebula. In both cases I seemed to have a very circular artefact being introduced on integration. When I removed/neutralised the background and stretched the image it looked like someone had taken a circular grinder to the centre of the images! I've been pulling my hair out to figure what was wrong with my set up given the images appeared much sharper than the ones I took for the M31 image and I also reset my goto after every 10 shots (my tracking seems to degrade after about 10 minutes so I recenter every 5 minutes).

Well, it appears it was all down to one misclick in my settings. I'd noticed a function that looked like it was ideal for helping to de-rotate images and had clicked it. It certainly did something! If I only had a brain!

I've gone back to my original integration workflow and I'm just doing the final integration on the Soul Nebula. The initial integration, with a quick background neutralisation and stretch, seemed to show nebulosity. Hopefully I can have it processed tomorrow (removing the background is going to be tough because of the vast star field and sheer amount of nebulosity in that region). If successful, I'll then process the Heart Nebula.

I'm not expecting much as my camera isn't modded so I think it's only 25% sensitive to Ha and 30 minutes total integration time just isn't long enough. But it will be good to know if it's worth doing 4 hours on it.

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Hi Ken, sorry to hear of your mishap but good to know you have resolved the problem. Look forward to seeing your images, particularly how much nebulosity your camera has picked up. Earlier in August I was trying out my 'new' 75-300mm lens on the Canon 600D and took some wise-ish angle shots including the area with the Heart and Soul Nebulae and Perseus Double cluster. The image below isn't great with much false colour but it was the sum of x80 45 second exposures at ISO 800, plus the usual dark, flat and bias frames (x50 each). There was a bright Moon up that night and moisture in the air but you can make out some shapes :-) On the right hand side you can see the Double cluster in Perseus. Having never seen the two nebulae before even this poor image felt an achievement. Good luck with your imaging.

NGC1027 HASN.jpg

Cheers,
Steve

 

 

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Hi Nige,

Very well done with this sequence of M31 at different FL's, I do like them very much as a record and I'm not going to pick any one of them out as I feel each one gives a different perspective on the object. You have certainly got me itching to emulate what you have done :-) Here's for clear, dark skies to come.

Cheers,

Steve

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I have just obtained a ball joint to attach to the top of my telescope to allow me to accurately align the camera when doing piggyback work (I was having problems with the camera mis-aligning in altitude). Now the finder, eyepiece and Camera all point to the same spot, quite helpful really;-) :-) Despite looking top heavy the ball joint has worked very well with no movement even with the big 75-300mm lens attached or the camera falling off at higher altitudes. The joint is rated for supporting 8kg. 

DSCF0005.JPG

Here's a wide view below (at a 75mm lens setting) of the area around the Double Cluster in Perseus, the Muscleman Cluster (Stock 2) is in the image. The image was taken on the 7th September using x50 forty second exposures at ISO 800 plus x50 flat and x50 bias frames. No dark frames were used in the processing. On the night of imaging there was a lot of moisture in the air and the usual light pollution. I was using my Canon 600D DSLR piggybacked on the Startravel refractor and Synscan Alt-Az mount. The images were stacked in DSS and images processed using StarTools. I have tried reducing the worst effects of the bad light polution by removing the luminosity from the red channel in ST's. This doesn't affect using the COLOUR module however.

PDC.jpg

Cheers,
Steve

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1 hour ago, SteveNickolls said:

Hi Ken, sorry to hear of your mishap but good to know you have resolved the problem. Look forward to seeing your images, particularly how much nebulosity your camera has picked up. Earlier in August I was trying out my 'new' 75-300mm lens on the Canon 600D and took some wise-ish angle shots including the area with the Heart and Soul Nebulae and Perseus Double cluster. The image below isn't great with much false colour but it was the sum of x80 45 second exposures at ISO 800, plus the usual dark, flat and bias frames (x50 each). There was a bright Moon up that night and moisture in the air but you can make out some shapes :-) On the right hand side you can see the Double cluster in Perseus. Having never seen the two nebulae before even this poor image felt an achievement. Good luck with your imaging.

Really good to see it's possible to capture both nebula with an unmodded DSLR. You can definitely see both nebula in the image and it's nice to be able to capture both with the double cluster. My field of view barely covers the Soul Nebula and I'll have lost quite a lot of the Heart Nebula (once I finally get to look at those images). I did think to take a third sequence between the two nebula and try for my first mosaic but the clouds came over.

I'm on my third processing attempt. Although I got rid of my circular artefacts, there were two or three really bad marks across the integrated image. Given I'd rotated the image slightly when I cropped it to remove the stacking artefacts, they were not horizontal/vertical and they didn't cover the full width of the image - they almost looked like a bear had clawed them!. I'm running the data again with no calibration other than auto detection of hot/cold pixels to see if it's the bias, darks or flats causing me grief.

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Ken, I look forward to seeing your image when it's ready, glad you found the problem and corrected it. ☺

Steve, I'm quite pleased with all the M31 images, it's quite a range of options considering I spent under £80 for the lenses, the 210mm f3.6 has a lot of potential as does the 135mm. I think the x2 adapter will be fine under dark sky's and it fits all 3 lenses so there's plenty of options available. 

Your first image is full of detail, definitely worth gathering more data on, one I must target myself.  Also that's a cool looking set up you have there :icon_biggrin:

last night I had a go at imaging M33, only it wasn't in view until 11pm so I spent an hour imaging  ngc6543 the cats eye nebula, this looks a difficult nebula to capture but is at a high altitude so it was relatively dark up there, I only got 45 minutes on each target due to sleep needed. I'm processing them at present and will post on completion if they are worthy ☺☺

Cheers and clear sky's 

Nige

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20 minutes ago, Filroden said:

Really good to see it's possible to capture both nebula with an unmodded DSLR. You can definitely see both nebula in the image and it's nice to be able to capture both with the double cluster. My field of view barely covers the Soul Nebula and I'll have lost quite a lot of the Heart Nebula (once I finally get to look at those images). I did think to take a third sequence between the two nebula and try for my first mosaic but the clouds came over.

I'm on my third processing attempt. Although I got rid of my circular artefacts, there were two or three really bad marks across the integrated image. Given I'd rotated the image slightly when I cropped it to remove the stacking artefacts, they were not horizontal/vertical and they didn't cover the full width of the image - they almost looked like a bear had clawed them!. I'm running the data again with no calibration other than auto detection of hot/cold pixels to see if it's the bias, darks or flats causing me grief.

While I was processing M31 420mm I had hundreds of very luminous green dots in the image, which I have never seen before, each one about 3 or 4 pixels in size but covering the entire image, the only way to get rid of them was with the final noise reduction in StarTools,  I'm wondering if not using darks was the cause of it. 

The green dots looked exactly like the small specks you get when setting a star mask in ST. I have no idea where they came from though.

Strange. 

It's a long learning curve ☺☺

 

Edited by Nigel G
spelling is bad ☺
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Well I new ngc6543 was quite difficult to capture, I think it needs a few more subs to gather the info needed, I got the cats eye but only a tiny fraction of its nebula. It is there but I must add a few hours to it.

M33 turned out ok for 45 minutes worth, again I will add more subs when the sky's clear up. It's another one where the colours are hard to pull out. I try to get the stars as natural as possible. Normally reducing the green and blue in StarTools. 

Both are around 45 minutes of 30s and 45s with darks and bias. DSS and ST. 150p alt az goto canon eos 1200d.

Cheers 

Nige.

PSX_20160909_134659.jpg

PSX_20160909_135436.jpg

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Not my finest work. I can't remove the lines that look like claw marks and I've given up processing it and just pushed it through a quick stretch in Photoshop. This is only 30 minutes of total image so I'm actually surprised to see anything. Going to see if the images of the Heart Nebula are any better.

Soul_nonlinear.jpg

Soul_nonlinear_Annotated.jpg

Edited by Filroden
Added annotated image
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8 hours ago, Nigel G said:

While I was processing M31 420mm I had hundreds of very luminous green dots in the image, which I have never seen before, each one about 3 or 4 pixels in size but covering the entire image, the only way to get rid of them was with the final noise reduction in StarTools,  I'm wondering if not using darks was the cause of it. 

The green dots looked exactly like the small specks you get when setting a star mask in ST. I have no idea where they came from though.

Strange. 

It's a long learning curve ☺☺

 

I hope you get to the cause of the green artifacts Nige. I haven't had anything like that all across the whole image but I have had green and red short tracks on a wide field image before where I hadn't employed any dark frames and did think that was the cause. Your mention of StarTools green specks, could they result from the use of the DECONVOLUTION module? I have noticed it sometimes leaves odd gaps of colour often only noticeable in a magnified view?

Anyway good luck sorting it out and do let everyone know what it is/how it can be resolved.

Cheers,
Steve

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4 hours ago, Filroden said:

Not my finest work. I can't remove the lines that look like claw marks and I've given up processing it and just pushed it through a quick stretch in Photoshop. This is only 30 minutes of total image so I'm actually surprised to see anything. Going to see if the images of the Heart Nebula are any better.

 

 

I'd put them down to your relatively short total imaging time there Ken. I've been re-reading Joseph Ashley's book, "Astro-photography on the Go" this afternoon and he did a review of the images people had placed on the Internet that they were pleased with. He came to the conclusion that 120 minutes total exposure was the point to aim for which practically might mean multiple sessions. TBH I've never achieved that level of exposures but if the night is dark then of course the more photons collected the better and the easier subsequent processing becomes. Don't be downhearted if the image of the two nebulae needs more work as you could add more images another night.

Cheers,
Steve

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3 minutes ago, SteveNickolls said:

I'd put them down to your relatively short total imaging time there Ken. I've been re-reading Joseph Ashley's book, "Astro-photography on the Go" this afternoon and he did a review of the images people had placed on the Internet that they were pleased with. He came to the conclusion that 120 minutes total exposure was the point to aim for which practically might mean multiple sessions. TBH I've never achieved that level of exposures but if the night is dark then of course the more photons collected the better and the easier subsequent processing becomes. Don't be downhearted if the image of the two nebulae needs more work as you could add more images another night.

My Heart Nebula was a bust. Like you say, I need far more photons for something this feint. I can't get above the noise with 30 minutes. It looks like another clear night tomorrow with little wind. I may see if I can get a couple of hours on the Soul Nebula though I'm tempted to park it as even if I got a couple of hours, by the time I crop the image, I don't think I can get it in a single shot. I'd need to do a mosaic which doubles the subs I will need :(

I'm thinking I might have to try something else tomorrow - probably adding more to my M31 image.

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9 minutes ago, Filroden said:

My Heart Nebula was a bust. Like you say, I need far more photons for something this feint. I can't get above the noise with 30 minutes. It looks like another clear night tomorrow with little wind. I may see if I can get a couple of hours on the Soul Nebula though I'm tempted to park it as even if I got a couple of hours, by the time I crop the image, I don't think I can get it in a single shot. I'd need to do a mosaic which doubles the subs I will need :(

I'm thinking I might have to try something else tomorrow - probably adding more to my M31 image.

Don't be too upset over this Ken, it's sometimes difficult to know how some DSO's will appear on the restricted images we can make with alt-az gear. I'm often uncertain over the different brightness values stated for DSO's on sites. Often you just have to try imaging to see what you find. What's more of a disappointment in the UK is we get so few clear nights that spending two or three on one object when you could be imaging three others is a hard choice to make.

Here's hoping it will be clear tomorrow night as promised in the forecasts.

Cheers,
Steve

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3 hours ago, SteveNickolls said:

 could they result from the use of the DECONVOLUTION module? I have noticed it sometimes leaves odd gaps of colour often only noticeable in a magnified view?

Anyway good luck sorting it out and do let everyone know what it is/how it can be resolved.

Cheers,
Steve

It could well be after decon , to be honest I didn't note at which point they appeared,  I think I was multi tasking at the time which is when it can take hours to process while doing my books or quotes, sometimes not paying full attention ☺

I will re do it during the week and see if I  can reproduce the same image.

Nige.

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I've been off-line for a while and all your image attempts are good for the soul. It's good to see progress being made, and I must get back into my stride; I haven't imaged for ages. Steve and Nige, your wide-field shots are tempting me in that direction too, but as Steve says, we get so few good nights and we have to choose.

Nige, don't forget that the StarTools log file allows you to see what settings you made and when you made them, so in theory you could manually step through each setting in turn and see when the green spots appeared. I always wish that ST could do this automatically, or at least present you with a history on-screen so that you can click through in turn.

Ian

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Andromeda -

Canon T6i with 100-400mm L series USM zoom set to 100mm

37 light frames taken at ISO 6400 for 25 seconds stacked in DSS and post photoshop 

Andromeda2_zpsqirwjlnw.jpg

One frame caught a meteor...

472A47C2-FC9D-4C13-ADBB-069746306AC3_zps

Edited by VSOP
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Nice one VSOP, and what a lucky capture, that meteor looks greenish.

It would be interesting to see what more frames could do. What aperture were you using?

Ian

Edited by The Admiral
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Round 2 - I apologise this is badly processed but here's what an additional 80 minutes of data can do...

IC1848 - Soul Nebula

54º34’N 000º59’W

 

Equipment

Skywatcher Esprit 80

Celestron Evolution Alt/Az mount

Canon EOS 60d

 

Images

 

Lights        Quantity    Exposure    ISO    Notes

Lights              160               30s                  1600     10/09/2016 21:54 to 23:47, 63% Moon, SQM 20.4

                        60                 30s                  800       07/09/2016 23:03 to 23:44, 36% Moon, SQM 20.3

                       110 minutes total integration    

                

Bias                                                                            Superbias used

Darks             30                   60s                   1600     Scaled to 30s in Pixinsight

Flats              32                   1/32s                 1600

 

large.57d58973381ca_SoulNebula20160910.jpg

 

Here's a link to the raw fits file if you StarTools gurus want to see if it can pull out more detail: https://1drv.ms/u/s!AvTUh2l4A9nVgck6uy56qgCfDIcBzA

 

Next step top is to take about another 130 minutes and see what four hours will show.

 

Edited by Filroden
Added link to fits file
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Hi Ken,

Thanks for posting this. I'm going to download the FITs file to see if I can process in StarTools later today.

Best Regards,
Steve

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Well last night regardless of the Moon it turned out to be very clear here. I was surprised firstly that when I was imaging the Double Cluster in Perseus that the Live View on the camera showed a dark blue background, usually it's a various shade of 'light pollution orange-red'. This morning stacking the images the master image in DSS was a dark grey colour and not the usual mucky orange hue. I rather think last night the sky was largely free of moisture so the level of scattered light pollution was a lot less than normal. I took x60 fifty second images of the double cluster at ISO 800 and this morning took the flats and bias frames (both x50). Again I did not take any dark frames. I used the usual equipment, the Synscan Alt-Az mount, Startravel 102mm refractor and my Canon 600D DSLR with a lens at 300mm. StarTools was able to process the images very well and I had no trouble in the COLOUR module and got a nice dark background automatically. The image is reproduced below, in the bottom left corner is the open cluster NGC 957. I love the double cluster and will spend ages now looking at the patterns and colours of stars v Stellarium.

PDC300mm.jpg

Cheers,
Steve

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9 minutes ago, SteveNickolls said:

Hi Ken,

Thanks for posting this. I'm going to download the FITs file to see if I can process in StarTools later today.

Best Regards,
Steve

It will be good to see if StarTools can do anything more. I still haven't mastered deco nvolution so it will be interesting to see if it can sharpen the image. I'm not happy with my processing but I'm much happier with the raw data.

It goes to show more data makes a huge difference though it also makes alignment much harder as I'm having to collect data over a much longer window and crop back much further. In hindsight I should have rotated my camera by 45 degrees to give myself more field to play with. Tonight could be clear though windy so I might try to add more data. The moon will start to interfere soon and I'm worried in another month it will be too high and rotated too much.

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Yes, time is not our friend as it could place the nebulae too high to work with. Looking back on my records September tends to be a good month for clear skies, so fingers crossed. I'll have a look at your downloaded file now :-)

Cheers,
Steve

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You ALT/AZ folks shouldn't think using an EQ mount is a bed of roses. Here's what happens if last night's PA is 12 hours out:

temp.jpg

At least its a good demonstration as it shows the effect an error twice the distance from polaris to the true pole. Now I have to find out WHY my PA display is suddenly showing it  this way.

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Hi Ken,

I've had a try with StarTools on your downloaded image. The COLOUR module did not like the data and would have washed the nebulosity firther away so I missed that step out. The background is becoming darker and some nebulosity is developing. If it had been a more regular shaped object using isolate/mask in the LIFE module can really bring out an object more. I hope you can get more data to get this to be a good success.

Cheers,
Steve

SoulST.jpg

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