4 replies to this topic

[james7ca]

This was taken at the prime focus of a Takahashi FC-100DZ fluorite doublet refractor using an uncooled ZWO ASI678MC "planetary" type camera. I combined 32 subs that were each exposed for 4 seconds so the total integration time was 2 minutes and 8 seconds. The image scale with this setup is 0.52 arc seconds per pixel and north is oriented up. The limiting magnitude on this shot is approximately 17 and I'm somewhat surprised that I got this sharp of an image since this nebula is pretty far south and fairly low on my horizon. However, I did use PixInsight's SubframeSelector to pick the 32 subs with the smallest FWHM (star size) out of my total of 450 samples.

 

I captured most of these subs while I was waiting for the planet Pluto to shift enough in the sky so that I could create an animation of its movement. That animation is in the following CN thread:

 

  https://www.cloudyni...#entry13613303 

 

Hopefully over the next few days I'll be able to increase my set of subs on the Saturn Nebula as that should allow me to do a drizzle integration to grow the image scale. However, if I don't get a clear night soon the moon will be getting too bright to do much broadband work, so we'll have to see what happens before the end of this weekend.

 

Image capture with N.I.N.A. using direct "guide" with dither, image processing with PixInsight and Photoshop 2024. There are additional capture details in the image captions. Click on the preview to see the full-sized image.

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Edited by james7ca, 08 August 2024 - 10:37 AM.

[randcpoll]

Well done!

[Yomamma]

This was taken at the prime focus of a Takahashi FC-100DZ fluorite doublet refractor using an uncooled ZWO ASI678MC "planetary" type camera. I combined 32 subs that were each exposed for 4 seconds so the total integration time was 2 minutes and 8 seconds. The image scale with this setup is 0.52 arc seconds per pixel and north is oriented up. The limiting magnitude on this shot is approximately 17 and I'm somewhat surprised that I got this sharp of an image since this nebula is pretty far south and fairly low on my horizon. However, I did use PixInsight's SubframeSelector to pick the 32 subs with the smallest FWHM (star size) out of my total of 450 samples.

 

I captured most of these subs while I was waiting for the planet Pluto to shift enough in the sky so that I could create an animation of its movement. That animation is in the following CN thread:

 

  https://www.cloudyni...#entry13613303 

 

Hopefully over the next few days I'll be able to increase my set of subs on the Saturn Nebula as that should allow me to do a drizzle integration to grow the image scale. However, if I don't get a clear night soon the moon will be getting too bright to do much broadband work, so we'll have to see what happens before the end of this weekend.

 

Image capture with N.I.N.A. using direct "guide" with dither, image processing with PixInsight and Photoshop 2024. There are additional capture details in the image captions. Click on the preview to see the full-sized image.

I have been hoping to get a shot at this one but summer weather has not cooperated.  That is a very nice shot of the nebula.  I have noticed that the brightness on this object is significant and have been contemplating what exposure lengths to try on my ASI2600 MC.  Looks like it wont be long lol but the histogram is your friend.

[james7ca]

randcpoll and Yomamma, thanks for the comments and similarly to everyone else for the likes.

 

I integrated all of my 448 subs and the image turned out sharper than I would have expected (since I didn't omit any of the poorer subs). However, even with over ten times the total integration time there isn't a huge difference in the image. I think a drizzle would help a bit with the detail but I deleted some of the intermediate subs and the drizzle in PixInsight failed since it couldn't find all of the processed subs. So, to do the drizzle I think I'm going to have to start over on all of the processing. I think a CFA drizzle requires access all the way back to the calibrated, non-debayered subs.

 

Also, I won't be getting any more subs tonight since north San Diego county's marine-layer clouds arrived shortly after sunset (as typical from May through September).

 

In any case, below is the integration that used all of my subs. There is a little color mottle, but the wings (Saturn's rings?) or FLIERs ("Fast, Low Ionization Emission Regions") from the central disk of the nebula are easier to see.

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Edited by james7ca, 09 August 2024 - 01:29 AM.

[james7ca]

I found out what was causing my drizzle to fail, apparently PixInsight's file cache for ImageIntegration had been corrupted and even though the file list in the process was correct and complete PixInsight wan't using all of the subs during the integration. In fact, the image that I posted in #4 was also affected by this problem (it didn't really have 488 subs, only about one half that number).

 

In any case, I was finally able to do the 2X drizzle integration and I've posted that new image over in the "experience" thread since I used some PixelMath to help denoise the image. I also included how I fixed my problems with PixInsight's ImageIntegration in the below, new topic here on CN:

 

  https://www.cloudyni.../#entry13616851