Atik Cameras Forum

Support (Please note, this is primarily a user forum, for direct Atik support, please email support@atik-cameras.com) => 3- and 4-Series Cameras => Topic started by: UlteriorModem on August 21, 2016, 03:03:44 pm

Title: Some odd artifacts 383l+ mono
Post by: UlteriorModem on August 21, 2016, 03:03:44 pm

I have noticed some odd artifacts in my images with the 383L+ mono.

Foremost is this diagonal line. Also there are some 'ghosts' of the mirror and diagonal. Here is a single flat frame that illustrates it.

(Note both images have been stretched and exaggerated to illustrate the artifacts)

(http://i259.photobucket.com/albums/hh312/UlteriorModem/Astro%20Photos/Atik%20stuff/Defects%20-%20flat_zpsdlrdzvkv.jpg)

Also when I stack and process LRGB channels I am getting some purpelish splotches

(http://i259.photobucket.com/albums/hh312/UlteriorModem/Astro%20Photos/Atik%20stuff/M15%20yuk_zpstl4drhtl.jpg)

I had a good close look at the protective glass in the camera and it appears to have a white speck of 'dust' on the inside of the glass.

Title: Re: Some odd artifacts 383l+ mono
Post by: Chris on August 22, 2016, 08:50:58 am

The darker circles of the flat are dust doughnuts, areas where dust particles on some component such as a filter is showing a reversed image of the scope aperture.
The overall shading looks like vignetting, some areas don't get the full illumination.

I've no idea about the diagonal line but it doesn't look as if it's a camera artifact.  Try rotating things to see what causes it to change.

All of this is what flat frames are for.  Dividing your image frame by a flat frame should remove these artefacts from the data.

It's difficult to say anything about the image, a processed image has had a lot going on. The darker circles in the top left look like dust dughnuts and a flat would help with these.

Chris

Title: Re: Some odd artifacts 383l+ mono
Post by: UlteriorModem on August 22, 2016, 02:25:13 pm

Thank you Chris,  :)

I have dealt with the dust motes. I am sorry I was not clearer about that in the original post. As I mentioned there were dust specks 'inside' the protective glass lens. Once the lens was cleaned inside and out they have been eliminated.

The diagonal line is almost certainly something to do with the camera. It rotates with the camera always in the same orientation and shows up regardless of which filter is used.

Furthermore after cleaning and replacing the protective lens surely the lens would have been rotated yet the diagonal line remains in the same orientation.

Yes these issues can be dealt with using flats however the camera is pretty new.

You are right about the processed image having a lot going on. I need to look at each channels stack but I have noticed in a few recent images. I 'thought' it was condensation but I was sure to let the camera cool for a good 20 minutes before that last set.

Just thought maybe someone might have seen it before.

Title: Re: Some odd artifacts 383l+ mono
Post by: Steve on August 22, 2016, 04:22:17 pm

Hi,

If you send in the camera serial number to Atik support we can check if the diagonal line was on the flats taken directly after the camera was manufactured.  It might help to narrow down the possibilities.
best
Steve

Title: Re: Some odd artifacts 383l+ mono
Post by: UlteriorModem on August 22, 2016, 09:01:34 pm

Thanks Steve,

I thought this was 'support' anyhow I sent an email to contact@atik-cameras.com

I hope that is correct.

Thanks again.