What is happening in my editing/imaging

[RemcoDutch]

Good evening!
Went out tonight (planning to shoot Orion / Pleiades) and when it turned cloudy I pointed my Canon 2000D (unmodded) with Tamron 18-200 towards Capella I believe the star is called.
Zoomed (Not sure what to call it) the lens to 100mm, F5.6, 6400 ISO, 2sec exposure.
Used Dark (50), Flat (20), Bias (28) and light (150) frames. 
Stacked with DSS (Havent got time / drive to look into Siril yet seems alot more complicated!).

While editing in PS c6 I got the images shown below.

1st image: This is after stretchin 4-5 times (quite agressively I think)
 

2nd image: Final image, so stretching, curve and substracting Dust and Scratches filter, which seems to have helped for the weird red square (?).
I am actually quite happy with this result, considering this was my 3rd time shooting and 1st time doing the frames and focus actually the right way!

3rd image is the dust and scratch filter I substracted from the 1st image to create the 2nd image (sorry for the weird order of posting)

 

Can anyone tell me what I am doing wrong?  Is the red just noise and did it get stacked weirdly in DSS?
What is and how to prevent that red square?

[The Lazy Astronomer]

Just a guess here, but it could be a stacking artifact caused by the fact that the edges of the individual frames do not perfectly align. Was this done with a tracking mount or on a static tripod? 

[RemcoDutch]

8 hours ago, The Lazy Astronomer said:

Just a guess here, but it could be a stacking artifact caused by the fact that the edges of the individual frames do not perfectly align. Was this done with a tracking mount or on a static tripod? 

It was with a static tripod ! 

 

[ollypenrice]

Yes, in that case I think The Lazy Astronomer is right: your frames won't overlap perfectly.

There's a free/donation plug-in for Photoshop which I think you'd find very useful. Hasta La Vista Green is available on Regelio Bernal Andreo's website, Deep Sky Colors.  It would help dispense with the green bias in your image.

To check your background sky colour in Photoshop is easy.  Choose the colour sampler tool in the eyedropper menu, set the sample to 3x3 or 5x5 average (in the top menu) and measure the background in different places. I like a background with all three colours the same and ideally prefer 23/23/23 RGB in Photoshop's units. 

Olly

[alacant]

10 hours ago, RemcoDutch said:

Used Dark (50)

Hi

2000D? Try losing the dark frames and cropping to remove the rectangle. I think It'll be cleaner.

Cheers

** If you ever get stuck, we do quite a bit of processing in Bar 'El Casino' in Sella;)

[RemcoDutch]

2 hours ago, alacant said:

Hi

2000D? Try losing the dark frames and cropping to remove the rectangle. I think It'll be cleaner.

Cheers

** If you ever get stuck, we do quite a bit of processing in Bar 'El Casino' in Sella;)

Thats amazing 😂. Such a small world! I am the owner of the Bed and Breakfast Villa Pico in Sella !

[AstroMuni]

13 hours ago, RemcoDutch said:

Havent got time / drive to look into Siril yet seems alot more complicated!).

Read this tutorial and that should make it clearer. https://siril.org/tutorials/tuto-scripts/

[slaine]

On 06/12/2021 at 22:19, RemcoDutch said:

Can anyone tell me what I am doing wrong? 

As others have already mentioned, it's frame overlap in DSS, and some of your frames have red banding around. I would just crop it, making Capella centre, then reset the black point, tidy up the noise and it looks ok 😉