First pictures with modified DSLR and narrowband filter

[AnonymousAnimosity]

Hello, I have recently upgraded my astrophotography setup with a modified canon 100D, a vintage zeiss 135mm f3.5 lens and the optolong l-enhance filter. My previous camera did not support wired intervalometers, now I can finally just leave it outside at night.

I have been lucky enough to find clear skies at home around the new moon (bortle 4 zone).

The first target was the cygnus region, shot with a 50mm/f2.5 canon lens (m42 to EF adapter hadn't arrived yet) at f3.2.  I took 36 3 minute lights at ISO 400. Looking at the red channel alone there is much more contrast and detail which I can't match in the full image.

After receiving the adapter I set out to shoot the elephant's trunk nebula. Over three nights of battle with the clouds I shot about 250 lights, mostly 2 minutes and one hour or so at 1.5 minutes.

I expected processing to be a breeze but it turned out more difficult than expected, I struggle lifting the nebula from the background. I have also noticed a weird gradient in the image, which I assume to be vignetting (i woke up at 4am to turn off the camera and forgot to take flats), is that correct? I think it might also be due to thin clouds that I did not noticed when I sorted the pictures. I should be able to remove it taking some flats now. I am not very satisfied with the result, this was my processing workflow:

1) Siril:

• preprocessing and stacking
• colour calibration
• background extraction (seems to work better than startools' wipe module for wide fields of view)

2) Startools:

• autodevelop
• bin 50%
• sharp and contrast module
• shrink stars
• entropy module (lifts up hydrogen alpha)
• noise reduction
• bump in saturation

Any tips or leads? The upper right portion of the background looks particularly hideous.

Yesterday the l-enhance clip-in filter arrived and I did a quick test at 50mm. The target was again the cygnus region, about one hour of 5-6 minute subs at ISO 800-1600. I have stretched it very conservatively because there seems to be a lot of noise, today I will do some tests to determine the optimal ISO for this camera. I appreciate the lack of stars but I expected more nebulosity, do I just need more data?

 

[AstroNebulee]

These are great images