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JGM1971

The "No EQ" DSO Challenge!

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Posted (edited)

1418643175_ScreenShot2020-07-29at9_06_27AM.png.430fe74099a52217a5295e3af038b49d.png

Messier 10 Globular cluster, with 115 x 10 second subs at iso 3200, moon very nearby. A bit of amp glow in the bottom left I just noticed, so gotta keep an eye on those in the future to crop out. I'd say this is a very big improvement from my messier 3.

Edited by Heskyyyyy
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Posted (edited)
19 minutes ago, Heskyyyyy said:

1418643175_ScreenShot2020-07-29at9_06_27AM.png.430fe74099a52217a5295e3af038b49d.png

Messier 10 Globular cluster, with 115 x 10 second subs at iso 3200, moon very nearby. A bit of amp glow in the bottom left I just noticed, so gotta keep an eye on those in the future to crop out.

1418643175_ScreenShot2020-07-29at9_06_27AM.png.430fe74099a52217a5295e3af038b49d.png.23e0c9e54386469b7e2ce2346e6be272.png

Wow nice picture you've got there! I hope you don't mind but I took the liberty to download a png of your picture and did some further processing myself using Siril and GIMP. I first did a background extraction in Siril to remove the gradient on the picture. I then transferred it to GIMP to crop the stacking artefacts, remove the color cast with curves and finally performed a slight desaturation of the background. There are residual artefacts on the upper right but that can be easily cropped. Keep up your good work!

Edited by Nerf_Caching
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2 hours ago, Nerf_Caching said:

1418643175_ScreenShot2020-07-29at9_06_27AM.png.430fe74099a52217a5295e3af038b49d.png.23e0c9e54386469b7e2ce2346e6be272.png

Wow nice picture you've got there! I hope you don't mind but I took the liberty to download a png of your picture and did some further processing myself using Siril and GIMP. I first did a background extraction in Siril to remove the gradient on the picture. I then transferred it to GIMP to crop the stacking artefacts, remove the color cast with curves and finally performed a slight desaturation of the background. There are residual artefacts on the upper right but that can be easily cropped. Keep up your good work!

Not at all! Very very nice :) 

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I just want to say thank you y'all for the tips so far on post processing. I'm likely to be getting an eq mount by summer next year, so these tips will totally come in handy. Please keep it up :)

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14 hours ago, Heskyyyyy said:

I just want to say thank you y'all for the tips so far on post processing. I'm likely to be getting an eq mount by summer next year, so these tips will totally come in handy. Please keep it up :)

The single biggest tip for post processing Alt Az images is to crop. Crop heavy! You need to remove all the stacking artefacts caused by field rotation before doing any other post processing otherwise it will be a nightmare. And those artefacts can reach far into an image so really stretch the image to see them, undo the stretch and make sure to crop inside.

Of course, the single biggest top for pre-processing any image (alt-az or eq) is use flats and either darks/flat-darks (for cooled cameras) or bias/bias (for uncooled cameras).

The goal is to get your starting stacked image to be as clean as possible to make the rest of the processing easier, especially gradient removal and colour correction.

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Posted (edited)
11 hours ago, Filroden said:

The single biggest tip for post processing Alt Az images is to crop. Crop heavy! You need to remove all the stacking artefacts caused by field rotation before doing any other post processing otherwise it will be a nightmare. And those artefacts can reach far into an image so really stretch the image to see them, undo the stretch and make sure to crop inside.

Of course, the single biggest top for pre-processing any image (alt-az or eq) is use flats and either darks/flat-darks (for cooled cameras) or bias/bias (for uncooled cameras).

The goal is to get your starting stacked image to be as clean as possible to make the rest of the processing easier, especially gradient removal and colour correction.

Will do. Thanks :D 

Edited by Heskyyyyy

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Posted (edited)

I finally got around to processing some of the stuff I have been shooting.  Here's a whirlpool galaxy:

WhirlpoolGalaxy20200420.png

Image captured as 100, 1.5 second @ 50% gain subs with the SVBONY305 and AstroDMx_Capture software.  Processed with Siril (stacking), StarTools (image clean-up, color balance), then GIMP (sizing and cropping) all in Linux. Darks, Bias & Flats were not used.  Scope was a SkyWatcher 250P with Synscan, however, tracking was done with INDI indi_skywatcherAltAzMount driver and no guide scope.  Synscan GOTO was not used.

Edited by JonCarleton
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Nice capture with colour.

It would be very helpful to other members if you could add the setup used and exposures taken please

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Thank you for the added info.

The colour on the left in what I call the eye is lovely.

I'm intrigued by the framing of the galaxy, did you heavily crop or just the stacking artifacts off? I always assume galaxies would be small in an image.

 

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Posted (edited)

That galaxy is pretty large, but the Skywatcher 250P (254mm X 1200mm) with the SVBony305 has a very tight FOV.  I struggle with that for really large objects, such as Andromeda Galaxy.  I have tried a .5 reducer, but it causes focus issues and probably needs an extension tube. 

There was a bit of cropping for drift between frames, but not much.  I'd say less than 5%.  I did shave a bit off the left side for centering, but again, very minimal. I also bined X4 the entire image, but that would not increase the "fill" of the galaxy in the frame.  Thank you for your kind comments.

Edited by JonCarleton

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I took this a while back with my ASI178MM, C6 and AZ GTi. Lots and lots of 0.3 second exposures.

m13-flatted.thumb.png.0ffc096eeede697e887a5c1240052d0d.png

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Posted (edited)
2 hours ago, Ags said:

I took this a while back with my ASI178MM, C6 and AZ GTi. Lots and lots of 0.3 second exposures.

I like that! Shows what can be done with an Alt-Az mount and long focal length, albeit at the expense of filling up your hard drive :).

Ian

Edited by The Admiral

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True - I have to empty my hard drive after each session!

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True to form, I missed again and still got an image.  I really am going to have to sit down and get good at plate solving.  This time I was aiming for the Trifid Nebula and ended up with the Lagoon.  I eventually did find the Trifid and have also included my reshoot of the Dumbbell Nebula that was my original mistake ( I was aiming for the Angelfish Cluster).

All of these are from my Skywatcher 250P/Synscan with a SVBONY 305 camera using AstroDMx_Capture.  200 subs @ 8 seconds/25% gain, 30 darks, no flats or bias.  Stacked with Siril, finished with StarTools and Gimp...mostly Gimp, as I am still stumbling along with StarTools.  I should also mention that of the 200 subs in each image, I had to eliminate as few as 15 in a batch and as many as 32 resulting from inopportune scope tracking (SynScan).

TrifidNebula20200817.png

LagoonNebula20200817.png

DumbellNebula20200817.png

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Decided to reprocess some images I took a while back, M61 with NGC4301 and NGC4929 circled.  Arrow points to SN 2020JFO.   M64 and M104

Meade LX90, Canon 70D, mixture of 30s exposures @ISO1600 + 3200.  Processed in Sequator and GIMP.

m61.jpg

m64.jpg

m104.jpg

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Sombrero galaxy has been a tough one for me.  I wish I could get one half as clear as that.  Last one I took, one could barely see the dark border.  Perhaps I'll try again this season.

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My M13 effort joining the "No EQ" party! 89 x 10s subs @ ISO2000. 130PDS on AZ GTi mount. 

IMG_20201023_120253.jpg

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