I've been looking at image shift between the subs coming out of my RC8 scope and RickS kindly lend me his starlight H18 with OAG so I could check flex. I found that using the OAG put all subs right on top of each other, checking the first and last subs to come out of the camera between 11:30pm and 3am gave zero shift across most of the image except for top left and right which had a 3 pixel shift in the Y axis only. No subs where rejected in either of these images and I just used the combined RGB images from maxim.
I was tracking M104 so I stacked it up. 9.33 hours total exposure, 10minute subs binned x1.
I thought I'd grab a little M20 before sleep. 1.5 hours RGB only 5 minutes subs binned x2.
I didn't shoot any flats or darks for this one but I think maxim has scaled other cal files to suit.
Great shot of the Sombrero. and good depth and colour in the triffid. Those dark lines I've seen before, caused by USB download speed problems resulting in gaps in the data.
Has a new OAG been ordered yet?
Regards
Keith
Edit: Jason is correct - pls ignore my ramblings.
Last edited by telemarker; 01-05-2011 at 08:41 PM.
Reason: Doh
Sombrero is nice, M20 has those artifacts which could probably be photoshoped out. Interested in what OAG you are using with the Tak, I am thinking of one myself.
It's the Starlight Xpress OAG integrated with the SX filter wheel which I got with the H18. Robin is using it with his RC8. I'll be using it with a FSQ-106ED once I get the right combination of adapters to get the !@#%$ thing to focus
No I haven't rushed out to order anything The big advantage I see after this test run is the number of subs that are not kicked out of the stack. Using Ricks OAG, all subs passed the checks where as my subs had a greater than 50% rejection rate, mostly due to roundness. Still, my flexy subs gave me this crop, which I have deconvolved and sharpened as much as I could to see the detail.
The starlight OAG has a C thread on top which suits their guide cameras nicely but no one elses. Scopestuff have a female C to male T adapter which may or may not allow you to use other cameras. I'm still looking into it. It does mate nicely with the starlight wheel though and I do use one of them
Crystal clear here tonight Greg. Got the tak mount back in the dome and am running with my qhy9 and flexy guide scope. We'll see if the better tracking on the tak mount improves the flex issue.
I like the M20 Robin...what's the black lines?data rejection or something?
Apparently it is overloading of the A-D converter in 2x2 mode, fixable by reducing the gain setting of the camera (sounds like an internal trimmer pot... I have asked SX for details).
Great shot Robin. Looks like you've been making great use of the clear weather. Trifid nice too, but perhaps a tad too much saturation for my liking. Agreed you've sure got nice round stars - must be tracking well!
Great images Robin. Looks like some data rejection problems with Trifid . Looks like dars are needed. Maybe a stack and data rejection in another program will fix the dark lines.
Hey Rob, it's great to get some clear sky for a change and clear all night is a real bonus.
Apparently it's a known problem with camera gain settings Doug. Rick already has the fix via email from terry @ starlight and I dropped his camera back to him this arvo. Thanks for the loaner Rick, now I know which way to proceed.
Here's an m20 from last night I'm still fiddling with. L binned x2 and RGB binned x3. This is from the qhy9 on the tak mount without the OAG and it still looks ok, even at that odd resolution, but the stars are no where near as sharp as the one with the OAG. Looks like I need to spend some money
and good depth and colour in the triffid. Those dark lines I've seen before, caused by USB download speed problems resulting in gaps in the data.
The big advantage I see after this test run is the number of subs that are not kicked out of the stack. Using Ricks OAG, all subs passed the checks where as my subs had a greater than 50% rejection rate, mostly due to roundness. Still, my flexy subs gave me this crop, which I have deconvolved and sharpened as much as I could to see the detail.
