Disaster HELP!

[KP82]

In DSS RAW/FITS settings, did you check the option "FITS created by DSLR or colour CCD" under the FITS tab?

If this option is unchecked, DSS would assume the source files are already debayered.

Alternatively set INDI to transfer RAW images in CR2 format (native to your Canon) rather than FITS. I'm not sure how you access INDI control panel on ASIAIR as I'm only familiar with Kstars/Ekos when it comes to INDI.

[Simon Pepper]

Thanks KP82 no I did not do this step, however now completed, but still unable to pull any ha data perhaps I have not got enough integration here or the modded camera isnt sensitive enough. I have the l extreme but decided against that last night as it caused me issues on the last time out. Perhaps this target needs some sort of narrowband to pull out details. @Lee_P more than happy to send you the files I have think its about 1.5gb of lights and darks. I didnt get flats and forgot bias was going to use master bias but they are CR2 format and DSS didnt like to mix. Also as KP82 has mentioned is it possible to go back to RAW CR2 format with ASIAIR or do we have to use fits?

 

Thanks 

 

 

[KP82]

With the Moon in its waxing gibbous phase, the condition isn't ideal for DSO imaging. For targets mainly in wavelength Ha, OIII and SII you could still give them a try with your narrowband filter. But any broadband images will end up with most details washed out by the strong moonlight.

I usually take breaks in imaging between first quarter and third quarter of the Moon.

[Simon Pepper]

Here is the tif after using the below options in dss seems rather green now lol. Still I cant complain with the help of you all I have gone from failing to mount working, slewing, guiding and dithering perfectly!

 

Autosave001.tif

[Lee_P]

Congrats, that's working perfectly. Having very green images after stacking is normal, and to be expected. The clue is in the Bayer Pattern -- RGGB. That's a lot of G! You balance it out in post-processing.

Here's an autostretch of your stack using PixInsight, it gives a rough indication of what you'll get once you balance the green:

 

[Lee_P]

Also, the L-eXtreme works well even with a bright Moon. You get some gradients but they're manageable. I reckon you've got things working well enough now that you can put the filter back into the imaging train. Just remember that you'll need much longer exposures, including for focussing.

The L-Extreme let me get this image of the Soul Nebula a few nights ago (6 hours integration time), even with a bright Moon nearby:

 

[Simon Pepper]

This is awesome Lee! I will add the filter back in then. Are 5 minute subs a good starting point or are we talking 6/7 or more? Got a lot to learn with this hobby clearly but going in the right direction! 

[Lee_P]

11 minutes ago, Simon Pepper said:

This is awesome Lee! I will add the filter back in then. Are 5 minute subs a good starting point or are we talking 6/7 or more? Got a lot to learn with this hobby clearly but going in the right direction! 

I'd say you're making really good progress! The sub length will depend on your camera. I use five-minute subs as standard. Maybe start with that and see? In a single sub you should be able to make out the nebula in ASIAIR's autostretched preview, but it won't look stunning. That's what stacking and processing is for!

[KP82]

1 hour ago, Simon Pepper said:

This is awesome Lee! I will add the filter back in then. Are 5 minute subs a good starting point or are we talking 6/7 or more? Got a lot to learn with this hobby clearly but going in the right direction! 

Use the histogram as a guideline. Usually having the peak between 1/3 and 1/2 from the left gives a good balance between the subject and the background noise/glow. You need to manage your expectations. Basic modded Canon DSLRs will be quite far behind in SNR (smooth image) compared to dedicated cooled astro cameras with the same amount of exposure.

When I used my NB1 narrowband filter on the Sh2-101 Tulip nebula, I did 4 mins subs. Using these filters on targets with predominant Ha emission (e.g. NA nebula, regions in Cygnus) will skew your results towards red.

Also post processing is just as important as taking the subs. PixInsight is a wonderful piece of software and could make your life a lot easier once you get used to its workflow and interface. But it costs quite a bit. Personally I've tried it but decided to stick to PS CC. Maybe when one day I get myself a dedicated cooled astro camera, I'll bite the bullet and order the license.

Edited January 24, 2021 by KP82

[Simon Pepper]

Thanks @KP82 and @Lee_P really useful information. I do want a dedicated camera but I know that will be more challenges with that and want to make sure i can get some good images before we blow some more monies down the rabbit hole! I use PS for the images I have got so far on my trusty star tracker, but agree may look to pixinsight in the future. Hopefully next clear night will be another few advances forward again. Clear skies!

[Simon Pepper]

Hi all,

So got another fairly clear night last night (91% Moon) and manged only an hour integration on the Heart Nebula. Using all the tricks and advice here this is what I got. There are some horizontal banding, nut this is down to the 5 minute subs on DSLR. Also there is some vignette, hot pixels and some dodgy coloured stars, however if I was better in post processing in PS I think I could improve it. I am still happy with the image (just dont zoom in too much), so thanks again all this thread really helped and I am sure it will help others that google it and end up here! 

 

Edited January 26, 2021 by Simon Pepper

[KP82]

1 hour ago, Simon Pepper said:

Hi all,

So got another fairly clear night last night (91% Moon) and manged only an hour integration on the Heart Nebula. Using all the tricks and advice here this is what I got. There are some horizontal banding, nut this is down to the 5 minute subs on DSLR. Also there is some vignette, hot pixels and some dodgy coloured stars, however if I was better in post processing in PS I think I could improve it. I am still happy with the image (just dont zoom in too much), so thanks again all this thread really helped and I am sure it will help others that google it and end up here! 

 

Excellent result for just an hour of integration. For predominant Ha targets like the Heart and Soul, the L Extreme works really well. At this image scale I don't see anything wrong, maybe just the fairly strong noise reduction (understandable for just an hour on a DSLR) and the gradient from the moonlight.

Did you take any flats and use dithering? The flats would have taken care of the vignette and dithering would help eliminate hot pixels.

It's worth purchasing the following addons if you are going to stick to PS:

https://prodigitalsoftware.com/AstronomyToolsActions.html

https://www.rc-astro.com/resources/GradientXTerminator/

 

Edited January 26, 2021 by KP82

[Simon Pepper]

Hey KP82,

Ha ha you have a very keen eye I was quite heavy on the noise reduction I had awful horizontal banding. I did dither, but I didn't take flats, only darks and Bias. I do have the Astronomy tools plug in but that didnt help with the banding for some reason, but the noise reduction did take most away. I have heard of gradient exterminator and will look into that. The hardest part for me was finding focus having to take 5 min subs just to barely see the diffraction spikes. I have noted exactly where focus is now on the redcat with the filter in. I may adjust it ever so slightly as I still not sure its perfect here? Knowing focus will save so much time though and means I could have gathered more lights.  

 

[Simon Pepper]

Zooming right in my stars have taken on a square look (facepalm) I’ll process it again and see what went wrong. Likely I had squareness instead of roundness when messing about!!!

[Lee_P]

Congrats, this is great! Really impressive for just an hour as well. Focussing is tough, especially using a filter like the L-eXtreme. If you've got the cash spare, I really recommend looking into an electronic autofocusser -- great for getting perfect initial focus, and also for automatic adjustments over a night when focus shifts due to temperature changes.