Need help with ZWO385MC setup in Stellarmate/Ekos

[George Gearless]

Hi all.

I've been using my ZWO385MC for planetary purposes and my DSLR for DSO's. I've only ever used my 385MC with Sharpcap. It's been working fine.

So the other day I wanted to see how it would fare on DSO's. I use Stellarmate and Ekos for that purpose. I took some test pictures and was quite enthused at the result and decided to go for a longer sequence. Each picture looked fine in the Ekos Fits viewer and so I left it to its own devices for about an hour.

The next day to my dismay I found out that all my pictures were 8bit grayscale. Argh! It was really my own fault for thinking that it was just 'plug and play'. But, oh well.

It took a while before I found the settings in Ekos where I set up the camera. But no matter what I do, the pictures always come out either 8bit or 16bit grayscale, depending on wether I've set it for 8bit Raw or 16bit Raw. I've also tried to set it RGB24 and it also turns out as 8bit grayscale.

The odd thing is that everything looks fine in the Ekos Fits viewer. Good colours and such. But when I view them in any other program, they are either 8 or 16 bit grayscale.

I'm pretty sure there's just some setting that I've overlooked. But I can't for the life of me find out where and what. 

Can anyone help me pinpoint the problem?

 

 

[skyhog]

If you shoot at raw16 and save out Fits files, stack in DSS, you should find the resultant image is fine.  

[George Gearless]

3 hours ago, skyhog said:

If you shoot at raw16 and save out Fits files, stack in DSS, you should find the resultant image is fine.  

Indeed I should. 

I did try and stack the images that I got even though they were 8bit grayscale. This was what I got from a quick stacking. As you can see, no colours:

 

[skyhog]

I just tried doing as I said with the 385 and it seems to work fine, so rather odd. I do know that raw8 gives the problems you describe. The root of the problem, as I recall is getting the software to correctly debayer the images. I know you can set the debayer pattern in DSS but what I've just tried seems to work with the defaults. 

[George Gearless]

23 minutes ago, skyhog said:

I just tried doing as I said with the 385 and it seems to work fine, so rather odd. I do know that raw8 gives the problems you describe. The root of the problem, as I recall is getting the software to correctly debayer the images. I know you can set the debayer pattern in DSS but what I've just tried seems to work with the defaults. 

Hmm...very odd.

I seem to remember theres a 'factory default' setting or reset button in there somewhere. Maybe I'll try that. When I find it :).

Thanks, though.

 

[skyhog]

You will have to pop back and let us all know how you get on. Seems to be a common query with this cam. 

Tharts a promising image by the way. Bit of a challenge with these tiny chips!! 

[George Gearless]

4 hours ago, skyhog said:

You will have to pop back and let us all know how you get on. Seems to be a common query with this cam. 

Tharts a promising image by the way. Bit of a challenge with these tiny chips!! 

Will do. Worried about what you said about this being reported before. We'll see.

Yeah, considering it's 8bit grayscale sloshed together with no darks or any other post production, it's at least recognizable

[Stargazer33]

What processing software are you using? 

This is from the NASA site:

Notes Regarding the Display of FITS Images
An application intended to render a FITS image for viewing by a user has significantly more responsibility than an application intended to handle other standard image formats (e.g., "jpg" or "gif" images). FITS data arrays contain elements which typically represent the values of a physical quantity at some coordinate location. Consequently they need not contain any pixel rendering information in the form of transfer functions, and there is no mechanism for color look-up tables. An application should provide this functionality, either statically using a more or less sophisticated algorithm, or interactively allowing a user various degrees of choice. (See also, a short introduction to astronomical image processing).

Furthermore, the elements in a FITS data array may be integers or floating point numbers. The dynamic range of the data array values may exceed that of the display medium and the eye, and their distribution may be highly nonuniform. Logarithmic, square-root, and quadratic transfer functions along with histogram equalization techniques have proved helpful for rendering FITS data arrays. Some elements of the array may have values which indicate that their data are undefined or invalid; these should be rendered distinctly.

The data array in a FITS image must have a dimensionality between 1 and 999, the boundaries inclusive, indicated by the NAXIS keyword. The extent of any coordinate axis in a FITS data array may, however, consist of only a single element. Hence an algorithm designed to render two-dimensional images will be capable of displaying a three- or four-dimensional FITS array when one or two of the axes consist of a single pixel.

Three-dimensional data arrays (NAXIS=3 with multiple elements along each) are of special interest. Inspection of the World Coordinate System (WCS) keywords in an image with NAXIS = 3 or more may indicate that one of the axes is temporal. Writers of viewer applications should consider presenting such an image in a fashion akin to that used for an animated GIF. Even in the absence of WCS indication of a temporal axis this time-lapse display technique can be effective, and application writers should consider offering it for all three-dimensional arrays.

A FITS image with NAXIS=1 is a one-dimensional entity such as a spectrum or a time series. Writers of applications intended to handle these one-dimensional FITS images should consider presenting such an image as a graphical plot rather than as a two-dimensional picture with a single row.

[George Gearless]

22 hours ago, Stargazer33 said:

What processing software are you using? ....*snip*

 

I have used several programs. But my prefered program is DeepSkyStacker. See my response to Skyhog for further.

 

 

 

[George Gearless]

On 11/10/2020 at 12:34, skyhog said:

You will have to pop back and let us all know how you get on. Seems to be a common query with this cam. 

Tharts a promising image by the way. Bit of a challenge with these tiny chips!! 

The non existant problem has now been solved. Here's an explanation of what happened and why I mistakingly thought I was in monochrome when I realy wasn't.

When you open the files in DSS that you wish to stack, a list is created with a description of each file. Such as exposure time, ISO (if relevant), Dimensions and...Depth. When I stacked the first batch I noticed that it said '8bit greyscale' in the description. Upon stacking I saw that the photo was monochrome and the histogram was black and white only. I then checked my settings in Ekos and sure enough, the depth was set to 8 bit. Aaargh!

Ok, so I then set it to 16bit Raw and fired a few sequences in the daytime of my living room with the 150 degrees adapter lens. Loaded them into DSS and to my dismay I saw that the description now said '16bit greyscale'. An improvement, but still greyscale. In my frustration and infantile rage, I turned to SGL for guidance. You commented within a few hours that if I'd shot them in 16bit Raw, they'd be fine once I stacked them. Did I listen? Oh no, not me. Better throw a hissy fit in the living room over the 'piece of s*** camera and the complete and utter incompetence of Stellarmates inventors', right?  At some point, out of boredom, I sat and fiddled around with DSS and discovered that what you suggested was indeed true. Once I stacked the 16bit greayscale pictures, the colour histogram popped out. Just as you said. Regardless of the '16bit greyscale' description. Sorry Skyhog...I should've listened. 😬

In my own defense; why the heck does it say '16bit greyscale' when it is in fact in colour? I did a bit of searching on the web and there is in fact an explanation for this. It's got something to do with debayering. But to be honest, I didn't quite understand it. Mostly because I'd lost interest now that my non existing problem had been solved.

Fast forward to last night. Set my sights on the Pinwheel galaxy, double and triple checked that the camera was set for 16bit Raw, caught it smack center and set the sequence to blast off 25, 2mins exposures. Because of the late hour, I hurridly dismantled my setup after it'd finished. As I gathered all the power cables in a bunch to carry them inside, I managed to drag my still plugged in laptop to the ground and smash it.

I'm not a clever man. 😭

[skyhog]

Glad you are up and running... I hope you can salvage the lap top though.. 🤔