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Mike_F

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About Mike_F

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    Star Forming
  1. Anybody else spotted this? http://hardware.slas...or-in-the-world Sample video here: http://www.canon.com...20130304mov.mp4 Looks like this would make one heck of a sensor for Astro work. 19 micron2 pixels! Wonder what the noise-levels are like?
  2. Yes, me too, and at the risk of hijacking Gaztronomer's thread - the Loadstar sensitivity is indeed amazing. The irony that I saw my first ever galaxy in my guide cam's picture has not been lost on me. Just 1 sec exposure is enough for it to show the core of M81 very clearly indeed. I just object to having to pay 35 quid for a piece of plastic to fix the lack of strain relief on what should be a very simple thing for SX to fix - on a camera that cost me the thick end of 400 notes.
  3. Totally agree with this. Received wisdom is that a guide exposure of less than one second is going to result in you "chasing the seeing" - i.e. seeing conditions will mess with PHD's sub-pixel calculations of where the star's centroid is. Initially, I wasn't going to comment on your camera because I have no experience with the Imaging Source cameras (yet); but since you asked the question I went and looked up the specs. If I'm reading your model number correctly - that seems to be a colour camera? If that's the case, then a dedicated mono guide cam is definitely a better choice. Here's the relevant extract from what I consider to be the PHD "bible" : http://www.rosecitya...deToGuiding.pdf (Page 13): "Because sensitivity and low noise are important to guiding, a color camera should pretty much never be used. The color filters substantially reduce the amount of light that reaches the sensor. Furthermore, differences in brightness between red, green and blue filters will cause errors in calculating the location of the guide star's centroid." If you're after recommendations, I've only got experience with a QHY5v and the Lodestar. The QHY5v is a great little budget cam and works well as a guider, but I found mine a little "noisy". Since moving to OAG, I've needed something a little more sensitive and quiet, and the Lodestar perfectly fits that bill. But, that sensitivity and silence comes at a commensurately higher price, and it's cabling arrangement is, ermm.. "sub optimal". You pays your money.. (etc.) Hope that helps.
  4. Too much noise sometimes can be a symptom of an exposure time that's too short. I normally use an exposure in the 1 to 5 seconds range when guiding with my Lodestar - depending on how bright the guide star is I've chosen. How long an exposure are you using?
  5. I was using a 2" extension tube - but even then I had to rack the focuser out quite a way because the scope was originally designed to be used with a diagonal - which adds a chunk to the optical path length in normal use. A longer extension will of course exert more leverage on the focuser and exacerbate any slop - which is why I decided to cut my losses and switch to OAG. (Well, that and I'm guiding an SCT - which with mirror flop as well has enough differential flexure issues on its own, never mind having a floppy guide scope as well.) For your Quattro - mirror flop shouldn't be an issue - so an ST80 should work well as long as you can get the whole rig sufficiently rigid.
  6. +1 for this. I had focuser slop problems with my Equinox 80 APO when I tried to use that as a guide scope. Even at that point in Skywatcher's range of refractor scopes, if you have the focuser racked out a fair bit to achieve focus - there's far too much play. All the expensive ADM dovetails and scope rings are pointless if the guide cam is waggling in the wind in a droopy focuser . Currently waiting for a clear night to set up the shiny new Atik OAG in the imaging train as a result.
  7. Just spoke to Steve, the new firmware is ready and should be up on the web site next week.
  8. Superb! Might just have to thank them in person for that news at AstroFest tomorrow.. Thanks for letting us know Sara.
  9. Mm, indeed. To be absolutely honest, that's why I hadn't given this issue much focus thus far. My mindset when I encountered the problem was "meh.. I'll just re-expose the L,G & B and make them all ~24K to match each other once I've got some usable subs." My guiding issues definitely have my undivided attention right now - but it was very interesting to see someone else having exactly the same problem with mean ADU values in the red channel. To my mind it rules out a number of software/installation variables..
  10. Yes - also using the Baader LRGB filters here. No, I haven't emailed Atik about it, I'm too busy using the miserable allocation of clear nights to sort out guiding issues at the moment (turns out to be a nasty case of focuser flex in my Equinox 80 apo pro - so am currently converting to OAG) I had planned to give it a go in Nebulosity at some point to see if it was Artemis rather than the 460 at fault - but haven't quite got around to it yet. I'll keep you posted if/when I do.
  11. Will be interested in your findings. My 460ex and Artemis exhibit exactly the same problem. I just can't get to the ADU value I'm after with the red filter in the train. Blue and Green are both fine.
  12. Duh.. (Bangs head on desk) Of course it wouldn't work.. Muppet.
  13. Dithering out the diffraction spikes effectively? Nice idea.. Could also just rotate the camera slightly in the focuser - might save a re-balance. Thinking about it, is rotation necessary at all? Wouldn't just ordinary dithering by a larger than normal amount do it? If all you want is a data source that contains what was behind the spikes to clone from, can't see why that wouldn't work.
  14. Ouch, that's £498 at current exchange rates! I still want one, but the price on that AB&S sell add was a little more palatable. (My TV 41 Panoptic cost less than the price he wants for that XW...) Cheers though, don't know how you guys keep coming up with these - your google-fu must be much better than mine...
  15. Dammit Dammit Dammit! No, I didn't make it in time - only just spotted that my thread lived on past my attention span. That's what I get for not subscribing to my own threads. (sigh) Thanks so much for the heads-up though E621Keith. I must be more diligent! You'll note that all the sources listing a new one that were suggested earlier in the thread are no longer listing them. Each one I contacted was a case of "Oh, is that still on our site? Sorry - it's out of stock, I'll get the listing removed." Looks like AB&S is going to be pretty much the only way now - unless one comes up here.. TBH, I've been a bit too absorbed in all the recently acquired imaging bits to be thinking about much visual work. Too much fiddling with cameras & filter wheels, guide scopes and apparently endless varieties of software..
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