A revisit to m101

[glennbech]

I had pretty good sky last night and had to grab the chance. Since I got a whole lot of low quality data last time, I decided to visit m101 once again.

Here is my first attempt

To my big sureprise I was able to do 420 second shots without over exposing. Thats' a first timer with newt & dslr.

I also popped a 2x barlow into the guidecam tonight and spent some time drift aligning the HEQ5 PRo with WCS. Since It's a semi-permanent setup It's getting pretty well aligned now.

I took 11 sky flats, 11 flat darks & 11 Bias frames. Unfortunately I felt asleep during the session, so no darks this time...

This is 20x420 seconds (about 2,5 hours) og data with my 400D, Skywatcher explorer 200, Baader MPCC & Neodyum filter.

The red channel is almost useless and is almost lost to noise. Im not sure what to do with that, except maybe to move, or get into narrowband imaging :-)

[Paliadon]

Well done mate, that is really a nice shot. Well worth the time spent. How long did you spend processing it?

[rich_t]

That's looking good. Regarding your question about the red channel noise, it seems that it's brightest down the left/right edges but could be white balanced out in the middle.

I'm in no way an expert at this but would flats for the red channel help, after splitting out the 3 channels, then recombine?

The blue and green channels look great.

Cheers,

Rich.

[Psychobilly]

Hope you dont mind Glenn I ran it through GXT for ya...

[ATTACH]21205[/ATTACH]

It could have done with a bit of cropping to get rid of the bright red lines around the edges as these seem to "confuse" GXT a bit...

Also the version on my PC looks a lot different to the version that gets displayed on the forum...

Peter...

[glennbech]

Thanks for the comments and suggestions. I now see that my laptop is not very optimal for processing. I didn't even notice the red bar on top of my image. It's like working blindfolded I guess.

Thanks for the effort psychobilly, GradientExterminator seems like an investment I might consider.

Paliadon; I have only done a quick processing. But I see that i seriously lack high quality red data. Im not sure how to obtain it in the light polluted sky I am in.... A CLS filter would perhaps be a wise investment as well?!

Here is a closeup

[Psychobilly]

Hi Glenn

Imaging from my site wouyld be inpossible without filters I use a CLS-CCD (Eos Clip-in) on the 8" and A Hutech IDAS P2 on the Megrez72 (2" fitted to the FF III)

Peter...