M20 Trifid Nebula in HA

[Craige]

My effort so far with M20 Trifid Nebula image in Ha. Imaged over the last few weeks.

ZWO ASI 174MM Cool @ -15 degrees
Total integration 41 x 5 min subs.
Darks, Flats and Bias applied.

Processed in PixInsight.

Higher Res - http://astrob.in/245968/0/

Any feedback appreciated.

Thanks for looking!

[ZeroID (Brent)]

Very nice indeed. The Hi-Res is showing a lot of detail and depth for Ha.
What was the scope specs ?

Are you going to do LRGB as well ?
How are you finding the cooled 174 ?
It's on my wish list. I have the 120mc as a guide camera and that is excellent.

[Craige]

Originally Posted by ZeroID

Very nice indeed. The Hi-Res is showing a lot of detail and depth for Ha.
What was the scope specs ?

Are you going to do LRGB as well ?
How are you finding the cooled 174 ?
It's on my wish list. I have the 120mc as a guide camera and that is excellent.

Hi Brent,

The cooled 174MM is paired with a Saxon ED100 refractor @ F7.2. This combo gives me 1.66 arc secs/pixel.

I am planning on gathering LRGB for M20 and trying my luck at combining in PixInsight.

I have found the cooled 174 MM to be great after using an uncooled DSLR. It does produce a bit of amp glow, but dark frames remove this effectively.

All in all very happy so far with my learning curve and this camera.

Cheers,

Craige

[ZeroID (Brent)]

Amp glow ?
I would have thought cooling it to -15* would take care of that.
I've built a sensor cooled 450D with full spectrum cut and that is pretty noiseless and without amp glow @ about 5*. I could get to about -10 quite easily but then dew\ice becomes a problem. Have to go with Glen's Argon modification I think.

Do you have any dew problems with the 174 ? I relaise it is sealed with silica internally but what about the front window external surface ?

Your Saxon compares well with my Lunt ED 102 F7 hence the question.

[rustigsmed (Russell)]

nice one, always looks strange in straight Ha! like you are missing a third of the object!

[Craige]

Originally Posted by ZeroID

Amp glow ?
I would have thought cooling it to -15* would take care of that.
I've built a sensor cooled 450D with full spectrum cut and that is pretty noiseless and without amp glow @ about 5*. I could get to about -10 quite easily but then dew\ice becomes a problem. Have to go with Glen's Argon modification I think.

Do you have any dew problems with the 174 ? I relaise it is sealed with silica internally but what about the front window external surface ?

Your Saxon compares well with my Lunt ED 102 F7 hence the question.

During the warmer months I have run at -15* and set up summer master darks and soon I plan to run at -25* for the cooler months and set up my winter master darks. My experience with the 174 is that if you go beyond 60 secs you will start to see a bit of amp glow when you aggressively stretch the dark. It processes out. I normally run between 180 - 600 secs depending on target.

I haven't experienced any dew problems with the 174 so far.

[Craige]

Originally Posted by rustigsmed

nice one, always looks strange in straight Ha! like you are missing a third of the object!

Yep I agree it does look strange without the extra third.

[RickS (Rick)]

Not bad at all. A bit of elongation of the stars - probably need to improve guiding a little or get rid of some flexure?

[Craige]

Originally Posted by RickS

Not bad at all. A bit of elongation of the stars - probably need to improve guiding a little or get rid of some flexure?

Thanks Rick!

I think it is a bit of both. I struggle with drift alignment. More practice 😀