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almcl

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About almcl

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  1. Try it during day time. Being careful to *only* have the guide camera connected, and no other image capture software running. You should only need a very short exposure to get a white screen but with a suitably short exposure it should be possible to get an out-of-focus image of a distant object if the ASI 120 is connected to the uncapped guide scope. Does this work? If not then what camera does Sharpcap report is connected? And have you got the latest ZWO drivers installed? (I use Sharpcap 2.9 as it was free and only needed for polar align so if you're using one of the lat
  2. To answer the first post point, if you are imaging with a reflector (of any sort) the guidescope mounting isn't the only source of flex. The mirror mounting can and does move as the mount and scope's orientation change and a heavy camera load hanging off of a Skywatcher focuser can also shift position. The shift to an OAG improved my imaging quite a bit. Stars were much rounder and I no longer got the image drifting steadily across the frame during the session. There's a thread here which describes a similar issue: and Oddsocks answer halfway down the page in this one
  3. Looks as if it could be differential flexure between guidescope and main scope? And, yes, until I switched to an OAG, I used to get something similar.
  4. I think the answer to your question is 'yes'. If you place the flat frames in the tab (I assume you used the different tabs for the differing exposures?) with just the lights and darks for that exposure, they should only be applied to that set of lights. You don't say what camera you are using, but mixing different ISO and exposure lengths in the same stack can be problematic - no harm in experimenting though to see what works best, but you might want to try stacking the various different exposures separately to see the results?
  5. I imaged for quite a while with my EQ5 and SW200p. I initially added the Skywatcher motors (the mount was purely manual to start with) but ditched those in favour of stepper motors and an AstroEQ. This gave horizon to horizon slewing in under a minute and guided at just over 1" oscillation. I still use the EQ5 when imaging with a 200 mm canon lens as its performance is more than adequate, it weighs a good deal less than my AZEQ6 and takes only a few moments to set up. I don't think Tom Carpenter (AstroEQ's inventor) is selling ready made units at the moment, but although my sol
  6. Can't give an identical comparison, but I recently acquired a ASI 2600 MC to replace my cooled Canon 700d. I wasn't brave enough to insert cold fingers into the camera, so its cooling merely reduced the EXIF reported temperature by about 10 or 12 º C. The few results the weather has allowed with the 2600 suggest that it's quite a marked improvement over the DSLR. Cooling set to -10ºC , no misting. No amp glow (my Canon suffered really badly from this), very low noise, lighter weight on the focuser. There were software problems initially; APT wouldn't download the image files,
  7. Yes, my thought being that it accounts for seeing differences in setting min move.
  8. One recommendation (which may or may not help) is to nudge the mount north with the controller before running the calibration. But I find the GA a bit variable on backlash: some nights it's 'guide in one direction...', others it's backlash compensation of 2000ms +' and others it's 'Backlash is small...'. I've never figured out a reason and the mount usually hasn't changed apart from being dragged in and out of the shed, of course.
  9. Hard to tell from a screen shot (at least that's what the developers over on the PHD2 group say) but did you do a guiding assistant run? It's always worth doing one at the start and accepting its recommendations. It appears that your oscillations are down around small fractions of a pixel, so assuming that all the figures were correct when you ran the 'New Profile wizard' that's probably close to the limit of what you can expect. I wouldn't sweat the PA too much, within 5 arc minutes is said to be fine and any Dec drift will be easily guided out. If you want an expert opinion,
  10. Glad you got there! Afraid I only have an ASI120 mm so my settings probably aren't very relevant but I *think* the ASI driver when you first connect PHD2 (assuming that's what you're using) will offer a choice of highest dynamic range, lowest noise or unity gain and will select appropriate offset and gain for which ever of these is selected.
  11. No, the camera sensor needs to be (approximately) where the first lens in the eyepiece was before it was removed. So loose the big extension as a first step, then screw the locking ring at the objective end further down the barrel and try screwing the objective further in. The moon is up now so you could try focussing on that?
  12. Thank you, Olly. Here's a stack (from ASTAP which doesn't use Bias/Offset) where bias files were used instead of the Dark Flats (hopefully not quite so black clipped - min pixel value is ~4): Whatever the cause, it seems that both DSS and ASTAP need the Offset/Bias files on this occasion, which goes against much of what I have read for the ASI 2600 MC. Downloading files from the 2600 has proved 'interesting' and generated a fair amount of activity both on the ASI site and the APT forum.
  13. Oh the frustration! Last night was the first clear night for 10 days, so I set out to do some simple imaging and to try out my new-to-me-home-made-cardboard+sealingwax EL flats panel. Weather was actually better than forecast so after taking nearly 90 minutes to get focussed and on target, I settled down to a run of 30 x 90 sec lights. For a change, the guiding on the AZEQ6 was reporting sub 0.5" oscillation (hooray!) We got to the end of the first run with no major drama so I set about a further 30. Halfway through this I discovered, while looking at the images in DSS, that some
  14. Processed in StarTools 1.7.455 with some messing about in Photopaint afterwards...
  15. StarTools (you can download a fully functioning version that does everything but save here to see if you like it) doesn't work in quite the same way as other post processing software. I used four separate modules to emphasize the galaxy: Autodev, HDR, Life and Superstructure. ST replaces levels and curves with mathematical functions to avoid loosing data such as the faint outer edges of the galaxy while avoiding star bloat. Its creator, Ivo Jager, @jager945 posts here and may give a much better explanation of the philosophy and function.
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