StarTools

Im not sure if it is my poor image quality or that I just have no idea what I am doing or combination of both. When I try to process the below image all i seem to get is noise. Just turns the picture into white pixels. If someone has time to run the image and let me know if Im just stupid then I would be very grateful. Thoughts?

Cygnus wide field.
Canon T3i 18mm lens
stacked and debayered in DSS

Thanks

Alan


https://www.sugarsync.com/pf/D743658_6420159_6949576

It's not white noise. It's nebulosity. The image below is the result of a single Auto-Dev, 50% bin, default wipe, default Life-Isolate with full mask, default color and default Denoise.

I haven't used DSS for awhile because I think it's junk. But if you could post the settings you used maybe somebody can figure our where the color went. I think there's a nice picture somewhere in your data.

Gary

torsinadoc wrote:Im not sure if it is my poor image quality or that I just have no idea what I am doing or combination of both. When I try to process the below image all i seem to get is noise. Just turns the picture into white pixels. If someone has time to run the image and let me know if Im just stupid then I would be very grateful. Thoughts?
Cygnus wide field.
Canon T3i 18mm lens
stacked and debayered in DSS

Hi Alan,

As Gary demonstrated, there is definitely something in there, but the data is somewhat challenged.
Can you talk us through what you used for acquistion (tracking mount?), how many dark, light, flat, bias frames, exposure times, etc. ?
My opinion of DSS is somewhat less harsh that Gary's Although the version that is currently in the download section has caused me a few early grey hairs as well... Are you using the latest beta version from the yahoo forums?

I can tell by the streakiness you took multiple frames but did not 'dither'. Dithering (moving the camera a little between each frame) will help spreading fixed noise patterns in your camera's CCD/CMOS chip around, practically negating it.
I can also see some gradients in the top left and to the right of the image. Did you use any flat frames? (they are probably the biggest improvement you can make to your images at the acquisition stage at practically no cost!).
I was definitely able to get some color out of it, but the color information in the image seems quite faint.
Did you shoot this at a dark sky site? I would typically expect some sort of background level or light pollution...
Getting data acquisition and pre-processing down pat (i.e. as optimal as possible for you gear and circumstances) is an important step toward achieving the best possible image in post-processing!

Cheers,

Ivo

Thanks for input.

It was 25 lights and 15 darks

It was a blue sight as far as light pollution. No filter (I have a CLS filter but wont fit the EFS zoom lens).

I dont understand dithering. Can that be alleviated with guiding or processing?

When I restacked in pixinsight, I was able to get some color out of the image in elements but I really like the idea of startools and want to figure it out

DSS settings were all default: standard stack, no drizzle, average light and median dark,

bilinear debayering
sigma clipping combination method
no RGB alignment.

Hi,

May I ask what version of the DSS u r using please?

Regards,

A.G

most recent beta

Hi Alan,

Here is reprocess of the data that you have provided . I am a novice at all this I think that others may have a better idea as to how process the data properly.

Regards,

A.G

well heck fire. I have a lot to learn! I at least know what is possible.

What workflow did you use? I tried to run it on my stacked images from pixinsight but was really really green
My stacking in PI was

batch preprocessing, check CFA to debayer and under debayer choose RGGB and VNG; -unchecked optimize dark frames;

main stacked, debayered image
https://www.sugarsync.com/pf/D743658_6420159_6940510

I guess I need to work on my imaging technique and guiding.

Really neat piece of software!

torsinadoc wrote:Thanks for input.

It was 25 lights and 15 darks

Great! Now make sure you acquire some flats next time. It will greatly help distinguishing gradients and vignetting from real nebulosity.

It was a blue sight as far as light pollution. No filter (I have a CLS filter but wont fit the EFS zoom lens).

Nice!

I dont understand dithering. Can that be alleviated with guiding or processing?

Dithering is actually something you'll want! Have a look at one of our user's (rcheshire) excellent write up on dithering. All should be explained.
http://www.synergous.com/flatpress/inde ... st-friend/

When I restacked in pixinsight, I was able to get some color out of the image in elements but I really like the idea of startools and want to figure it out

DSS settings were all default: standard stack, no drizzle, average light and median dark,

bilinear debayering
sigma clipping combination method
no RGB alignment.

Looks good.
A.G did a fantastic job with the data at hand and his colors are very similar to mine. The thing is though that there is a rather red bias in both his and my image and I'm trying to understand how that got in there...

Hmm since Im not guiding and just using lens, I guess i can manually bump the camera a little over between images

Everyone has been very helpful with AP. I have no idea how we did this prior to the internet