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Brent

Bubble Nebula - NGC 7635

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I set up on Friday 16th under a full moon with a plan of just testing the polar align routine in SharpCap. It works really well, actually better with my mount than Alignmaster now that I have some backlash issues. It takes backlash totally out of the equation! Thanks to @themos (PhotoPolarAlign author) and @rwg (Robin, SharpCap author) for this great feature. It was really fast and easy to do and I'd thoroughly recommend it!

Anyway, having accurately polar aligned in record time I thought it would be a waste to let a clear sky go unused when I was already fully set up, full moon or not.

This is 45x180s of lights (limited length subs due to the moon), 50 flats and 50 bias. Captured in APT and processed in DSS and PS.

It needed a REALLY healthy dose of HLVG which I'm guessing could be due to the full moon (?) as I've never really needed to use it before.

Equipment:
Canon 350D (Full Spectrum) with CLS-CCD & Baader Mk III MPCC

Skywatcher 150p
Meade LXD75
Finder Guider

Thanks for looking.

BubbleNebula_45x180s_ISO800_DrizzleX2_PS-FIN_8bit.png

Edited by Brent
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I did not know sharpcap has a polar alignment ability--cool--how is it done?  This target is tough in RGB--much more signal in narrowband.  But the RGB images are very nice--realistic.  So I like it.  Just need some more data.

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Thanks Rodd.

SharpCap's polar alignment routine is remarkably easy actually. I used a finder guider with a Philips SPC900 LX webcam, and the plate solving is standalone and included in the download, i.e, no internet connection required once installed. The finder doesn't even need to be closely aligned with the scope as long as it's FOV is within 5 degrees of the NCP. The procedure is detailed on the SharpCap website, but a short description:

1) Do a usual polar alignment via the polar scope, but anything within 5 degrees seems to be acceptable (so you could theoretically have no polar scope and eyeball it!)

2) Set the scope to polar home and take an 8 second (or so) exposure.

3) SharpCap will plate solve it (in under a second in my experience!)

4) Move the mount about 90 degrees in RA. Take another exposure.

5) SharpCap will plate solve the second exposure, then compares the two images and works out the centre of rotation.

It then tells you how many arc-minutes/seconds to move the mount in simple terms (up/down/left/right) and shows a visual overlay with an arrow and a circle to move a given star into. This is updated onscreen as you move the mount bolts and new exposures come in. (I had a slight issue here which I'll have to report to the authors, but overall it couldn't be simpler!)

Hope I haven't missed anything (apologies ro the authors if I have), but have a look at the SharpCap site for a more detailed version.

Edited by Brent

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2 hours ago, Brent said:

Thanks Rodd.

SharpCap's polar alignment routine is remarkably easy actually. I used a finder guider with a Philips SPC900 LX webcam, and the plate solving is standalone and included in the download, i.e, no internet connection required once installed. The finder doesn't even need to be closely aligned with the scope as long as it's FOV is within 5 degrees of the NCP. The procedure is detailed on the SharpCap website, but a short description:

1) Do a usual polar alignment via the polar scope, but anything within 5 degrees seems to be acceptable (so you could theoretically have no polar scope and eyeball it!)

2) Set the scope to polar home and take an 8 second (or so) exposure.

3) SharpCap will plate solve it (in under a second in my experience!)

4) Move the mount about 90 degrees in RA. Take another exposure.

5) SharpCap will plate solve the second exposure, then compares the two images and works out the centre of rotation.

It then tells you how many arc-minutes/seconds to move the mount in simple terms (up/down/left/right) and shows a visual overlay with an arrow and a circle to move a given star into. This is updated onscreen as you move the mount bolts and new exposures come in. (I had a slight issue here which I'll have to report to the authors, but overall it couldn't be simpler!)

Hope I haven't missed anything (apologies ro the authors if I have), but have a look at the SharpCap site for a more detailed version.

Wow--I have Sharpcap too.  I will have to give it a try.  Thanks.

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