M79 - Dsi Ii

[dcalleja]

Heres an attempt at M79 with the DSI Pro II. I'm still having issues getting the LRGB layers to register and this tends to make what was pretty good focus look mushy. I've tried Meade's IP and Deepskystacker but I always seem to have some alignment issues in Alt Az (I do use Drizzle for de-rotation but to little avail).

This was prime focus a f3.3 on the Lx200 8"
Guided using ED 80 and DSI Pro
20x30 Sec subs for L and RGB @ 15sec
Post in PS CS3.

[iceman (Mike)]

Good result Dan. The star colours look nice. I know what you mean about the focus though - that was going to be my comment.

[Ric]

A good effort Dan, but as you say just a bit soft on the focus.

Cheers

[Lee]

Well done - getting RGB layers to properly register is a pain..... one reason I don't bother for the moment! Image looks good - its usually the blue layer that lets focus down I think....

[theodog (Jeff)]

Nice image Dan.
Do you re-focus between RGB's?
I have enlarged a star image from the edge of your field and noted the different sizes of the RGB images. I had this issue and focus checks between subs seemed to help.
Combining can be a tricky business even without rotation.
Well done.

[dcalleja]

Thanks Guys
When I was using the Meade filters - the difference in focus was huge so yes I did refocus. With the Astronomik filters I thought they were parfocal (and they looked it) but clearly not OR I am getting some movement (mirror shift) over time.

Clearly I do need to refocus in between filter runs. On the registration front - I'm going to give Polar a go and see how i go without drizzle.

Thanks again.

[Ric]

Hi Dan, I usually make it a point to check and refocus between filters with my DSI II. It does take a bit longer to get the image and you may not get to image everything you want but the final result will always make up for that.

Cheers

[dcalleja]

Ric
It's good advice - now if these clouds will move I can go out and put it in practice. I swear there have been more thunderstorms in Sydney in the 1st few weeks of summer this year than I can ever recall in past years

[Ric]

I now what you mean Dan, my wife reckons she's had enough of me grumbling about the house and mumbling about the clouds

She's at the point where she is now checking the weather on the net to see when the next clear night is going to happen.

I reckon it will a quiet night on IIS when the cloud finally does break.

Cheers