A single sub

[LewisM]

Only managed 3 x 200 sec frames of Barnard 33 tonight before the cloud rolled on in. All the stacking programs rejected the frame calibration - probably due to the blooming - so I took just ONE of the 200 sec frames and did a simple stretch (I knew what to expect, as MaxIM was doing the autostretch as they downloaded).

So, this is just ONE 200 sec frame,with no bias or flats (auto-dark from MaxIM), binned 2x2. Taken with the old SBIG ST-8XE through the Vixen DED108SS astrograph (manually focused - still awaiting the Sharpsky I ordered last week). Vixen GPD2 mount, Synscan GOTO kit. Cooling was only at -14.8°C.

I have cosmetically removed the 2 bloom "runs". Got to find how short a sub I can go and not get blooming blooming :D

Drooling at the thought of what a couple dozen more frames will add! And then when the moon goes, LRGB.

I am LOVING my new found NB toy :D

Cruddy severly converted png-jpeg below (why this BBS so radically alters PNG's?) and good definition astrobin upload: http://www.astrobin.com/full/61271/?mod=none

[multiweb]

Looking good. Now you just need to do a couple of 10min subs. HH is pretty faint. :thumbsup:

[LewisM]

Merci mon ami!

Went through my other test/framing images, and found a non-binned 200 sec exposure. I haven't bothered trying to remove the bloom with this one (note to self - need some SHORT SHORT subs in this stack)

http://www.astrobin.com/61288/

[multiweb]

CCD Stack has a deblooming algo that can reject all that stuff. Field looks good. Now you can go longer.

[LewisM]

CCDStack, CCDAutopilot and CCDInspector purchased :) Now to figure them out.

CCDInspector reports 6.1% curvature for this scope for most images. The 3D plot is VERY flat, and good even distribution all over. Not perfect, but not bad either. Min FWHM on most images 0.96, so I got focus fairly close.

Now to figure out CCDStack...

In the meantime, here's a taste of things to come with the Ha sub converted to glorious Sidonio colour :)

[LewisM]

Worked out CCDStack (easy), and stacked all the 5 subs I had worth keeping.

Improvement over the single sub, but it's got a LONG way to go yet. Badly repaired blooming (CCDStack made a SMALL improvement only, unfortunately)

I am deliberately resisting the urge to do M42 this season. :)

http://www.astrobin.com/full/61424/?mod=none

[LewisM]

For a laff, I blended my Ha data above with a VERY old, severely overstretched, over-smoothed and black clipped B33 jpeg image I took 2 years ago.

:rofl::screwy:;):P

It is NOT intended to be even remotely serious - it's a fantasy, throw away humour piece.

[multiweb]

Process>Data Reject>reject blooms

Set saturation low enough to just hilight all blooms.
Once they're painted:

>interpolate rejected pixels width(std) 3 iterations 3 > Apply.

On your original raw FIT the values might differ slightly but you get the idea.

[LewisM]

Yes, I found that through experimentation, but for some reason, even though it "paints" the entire bloom, it leaves a bit in the stacked image. Not bad, but still a little.

It's an IMPRESSIVE bit of software. So darned quick and easy to use! I thought the PI BatchPreprocess algorithm was fast... CCDStack is lightning quick, and uncannily accurate.

You get what you pay for :)

[Rex]

wow Lewis, you captured a bit of detail in that first one for a single sub.

[LewisM]

Yes, this scope/CCD combo is surprisingly sensitive - sometimes TOO sensitive, as the blooming on the bright stars is happening at times UNDER 2 minutes, and that is in H-a. The scope is an f/5 refractor with a 4" focuser, so it grabs as much light as you can throw at it - my downside is my step adapter to the camera - I still have to have the cone adapter made (done the drawings, keep forgetting to send them to my fabricator)

The 5 sub stack is a little cleaner, but not a lot.

[multiweb]

This is because you interpolate with the neighbouring pixels on the same sub. Hard to make up data. But it you use de-blooming with a stack of subs and dither accordingly you won't have many artefacts left.

[astronobob]

Magic single sub Lewis.

[Peter.M]

Whatever software is reporting this has to be setup wrong. Your seeing can't be that good at your site and even if it was the image scale you shoot at would not be able to record a half maximum of below one pixel.

Its good to see an alternative scope capturing data from the general stuff out there.

[RobF]

Sounds like you're having fun with it all at least Lewis.
Nothing like the thrill of a first sub dropping your jaw coming up on the screen to further the astro-addiction!

[LewisM]

Peter,

Yeah, it was an incorrect measurement in CCDInsp.

I have attached another one though. I simply plugged it into CCDInsp, and it read the header data etc.

[LewisM]

Indeed. Will be making this the target proper now for a while. Testing is not over though, as I have yet to fit the Sharpsky autofocuser :)

I also imaged NGC1365 that night. Not the best idea in H-a, but it worked. I even called the wife to show it CLEARLY on the monitor, and she was impressed to SEE something for a change ;)

[Peter.M]

Imaging at 3.43 arc seconds per pixel a FWHM of 1.2 would mean that you have a single pixel at full brightness and pixels on either sides of it are less than half of that intensity. I would make sure that the fits headers are correct because the most valuable tool you could ask for wont work without it (platesolving).