Why is my Mars green?

[Moonshed]

Okay, I bought the ZWO ASI224MC colour camera and a flip mirror. I have run 8 videos of Mars the last few days. The problem is that after stacking in AutoStakkert and getting an image it is always green, this is before any processing. I have discovered that all of my videos are a little out of focus but have discovered today how to correct that by starting in APT and focusing with their Bahtinov Mask.

However, the poor focus does not affect the colour and even after trying  everything in Photoshop I cannot get rid of the green.  There does not appear to be any red in the image that I can bring out. I have no idea why.

I took a 90 second video using FireCapture. The finished image after staking in AutoStakker is attached.

What am I doing wrong? It’s driving me nuts.

 

DFF121FD-92B1-4621-A51D-9E13A3488C65.tiff

[Freddie]

Check your debayer setting as if it is wrong the debayered image will not show the correct colour.

[ollypenrice]

The colour filters, a red, two greens and a blue, are placed in a pattern known as a Bayer Matrix over the pixels on your chip. Each pixel, therefore, captures just one colour. However, the patterns vary from maker to maker so you need to instruct the software as to which pixel gives which colour.

This is known as debayering and you have to find the correct pattern.

Olly

Edit, crossed with Freddie who's making the same point.

Edited November 11, 2020 by ollypenrice

[vlaiv]

Indeed, two possible reasons:

1. Wrong Bayer matrix type selected when debayering

2. Just missing color balance.

In fact, most of my planetary captures with dedicated planetary cameras turn out rather green, like this:

(this is actual Jupiter stack without any processing)

Here are details on how to obtain color:

But probably the easiest way to do it would be simple auto color balance function - that works pretty good. Here is what Registax 6 gives for your image:

Unfortunately, it looks like it was case 1) - wrong Bayer matrix. When I try to correct above "by hand", this happens:

This color usually happens when Bayer matrix is wrong.

 

[Moonshed]

Thank you all so much. I have played around with the debayering in both FireCapture and AutoSkakkert and managed to get some fairly reasonable colour of my living room ( total cloud cover) from what previously was pretty much only greyscale. I have found a YouTube tutorial and shall work my way through it but at least I now understand why Mars was green. I shall continue to try and experiment to get the most realistic colour of Mars when the sky is clear again.

Thanks again, I really appreciate all your help.

[Moonshed]

On 11/11/2020 at 16:17, ollypenrice said:

The colour filters, a red, two greens and a blue, are placed in a pattern known as a Bayer Matrix over the pixels on your chip. Each pixel, therefore, captures just one colour. However, the patterns vary from maker to maker so you need to instruct the software as to which pixel gives which colour.

This is known as debayering and you have to find the correct pattern.

Olly

Edit, crossed with Freddie who's making the same point.

I have used the debayer in FireCapture while observing Mars and adjusted the settings until the colour looked realistic on screen and then starting recording, so far so good. However, when trying to open the AVI of Mars in AutoStakkert  it wouldn’t open, just kept giving me an error message, I have shown this in another thread “Weird error message in AutoStakkert”.

I checked around online and found a few people who said after debayer is done it should be deselected so as not to be in force during recording. I don’t understand, why do it and not use it?
Have I got this wrong? Could you let me know if after getting the colours right do you record it like that, or switch debayer off.

I am so confused.

Edited November 14, 2020 by Moonshed

[Moonshed]

P R O B L E M   S O L V E D!

I had tried everything under the sun but still Autostakkert point blank refused to open any of my files. In desperation I thrashed my laptop within an inch of its life with a hefty branch, but still it refused. After days spent at the keyboard my back ached, my neck is stiff and I have a constant headache. My wife wisely has kept away.

Enough! I cried as I raised a 10 lb sledge hammer high above my head, but.....wait....I have one last thing I haven’t tried. 
I uninstalled Autostakkert and downloaded another copy and installed it.  IT WORKED!

I realised what I had done wrong. My desktop had become so cluttered over these last few days I decided to have a tidy up and trashed a lot of stuff I didn’t need. However, I trashed an extension of Autostakkert that I did need, something called a “sharpen_filter”. 

I can’t believe I spent all this time on trying to fix it!

live and learn.

my wife is talking to me again😄

 

[Guest]

And that's why I'm just a visual observer! 🙄