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This is my first post though I’ve been a member for some time (15 years I think). I’ve dabbled with imaging since 1999 with some success on the planets using the colour SXMX5C and then a Toucam Pro 2 webcam. The images were taken from my 10″ Meade LX200 Classic with tripod. This was a temporary set up. Now I’m fortunate in having a permanent set up in a sliding roof observatory and have been slowly gathering together the ‘bits and pieces’ I purchased over the last twenty years or so. It has been both interesting and frustrating. Interesting to read the glowing publicity from Meade in the 1990’s about the LX200 imaging capabilities placed on wedges and what is now said about them. I now understand the ‘wobbliness’ of the system. The most frustrating aspect though has been the relentless obsolescence of my equipment. My old SXMX5C camera used Windows 98 (or 95) hence won’t work with new hardware and software. Fortunately my old Windows XP laptop still works so I can minimise software upgrades for the meantime. I can use the second laptop for the webcam, SkyMapPro6, Registax and Astroart and it’s pleasant being offline – it’s all gummed up now inside but ok with minimal applications and no internet.
I have spent the last few months working steadily to establish a moderate platform for imaging – polar alignment via the drift method, worm PEC training, mounting my Takahashi 60mm on the LX200 while learning to use the new SXUltrastar for imaging. I’ve worked through issues of dead LX200 condenser, dead buttons on the hand box, assorted driver incompatibilities. As I read somewhere – astro-imaging is work. I’ve had some kind advice from David Arditti – hugely appreciated – and a morale booster.
Anyway to my question(s). I wish to do wide field imaging with the 60mm then later try small galaxy imaging with the LX200 putting on the focal reducer to get it down from f10 to f6.3 – subject to figuring out how to get focus with the micro-focuser attached while not incurring image train flop. I have got my old Toucam Pro ii working ok and possibly the mount using PHD for Windows (XP version). Can I guide with the webcam? Are their ‘bits’ that can make image and guide star location easier without resorting to undoing the attachment screws of the piggybacked 60mm? I think my system is cross-eyed the way it keeps pointing erratically. Is the Meade pier and wedge set up just too wobbly? Can adaptive/active optics – like the SX attachment help with the mount? The latter is expensive and perhaps for later on.
I’ve had reasonable results with the Ultrastar in imaging M31 – 21No. frames of 30 secs stacked. How far can short exposures and stacking overcome a wandering worm and hard to polar align mount? I’ve read that a decent mount is so important and really is the only solution. However I don’t wish to dispense with the set up I have. My old book on imaging of 15 years back shows nearly everyone using an LX200 – and producing some decent images too. And the LX200 is an easy to use visual telescope.
Sorry about this long note. I could write a lot more of the challenges of struggling to achieve a decent imaging set up. On a positive note – webcam imaging of Jupiter, Saturn and a partial eclipse was really easy to do. But these were ‘snaps’ of course. I hope someone can advise on webcam guiding and if the Classic LX200 communicates ok through PHD. The latter has indicated webcam and mount are ‘connected’. I have not yet moved to the PHD ‘Calibration’ stage. I’m waiting for a clear night to try.
Cheers, Ron (Morley)
Hello Ron,
Firstly, I don’t have any experience with PHD, sorry!
However, from 1997 to 2003 I did regularly battle with my own LX200 and faced the same dilemmas as yourself, except that I also had huge non-Go To Newtonians at my disposal.I initially used an SBIG ST7 with a built in autoguiding chip with my LX200. The arrangement worked, BUT, was always a hassle to set up. It was far less stressful to simply take multiple 60 second (or less) exposures, especially as I mainly imaged comets that moved in longer exposures anyway. Mind you, I was never a mega-long exposure Deep Sky imager anyway. As well as comets I imaged novae, supernovae, and other objects for which a set of 60 second exposures was good enough.
My biggest problem though was with the LX200 itself. On the 2nd night of use the RA motor/gearbox failed. This was soul destroying on a brand new £5K instrument. Eventually the dealer replaced the entire telescope, but the problems continued. Once or twice a year the telescope had to be dismounted and sent back to the dealer for new motors to be fitted….. This went on for 6 years. I examined the motor/gearbox assembly and was horrified to find a (literally) Scalextric toy car motor providing the drive to the gearbox chain; the gearbox consisting of tiny plastic wheels, glued onto shafts before the final worm stage. It was this gearbox/encoder system that always failed. On full slew the motor spun at 14,400 rpm (gulp!)
After I found this out I never slewed the telescope again, just synced on a star and crawled to the right RA and Dec, or unlocked the axes and pointed the LX200 manually. Eventually I gave up and simply used the LX200 for planetary work. But I dreaded even going outdoors at night for fear of the drives failing yet again. I bit the bullet and acquired a Paramount ME & C14 at this point (2003) which has never let me down. I temporarily remounted the LX200 tube on an EQ6 but this was not a brilliant solution as the 12″ tube was a bit too heavy (your 10″ will be considerably lighter though).
I’ve gone off topic here and not really answered your questions Ron, but, suffice to say, with my own LX200 the only way I could use it without loads of night-time hassle was using multiple short exposures and never slewing at high speed. There was not enough time between breakdowns to enjoy using the system and to perfect autoguiding. Eventually I grew to really hate the telescope with a passion!
I guess what I’m saying is, a decent modern mount really is the best solution. Even a humble NEQ6 Pro is in a totally different reliability and stability league to a vintage LX200. It’s like the difference between a BMW 5 series and a Morris Marina!
Hopefully someone else can answer your PHD query.
Good luck!
Martin
Hi Martin
Thank you for your wise words. I had begun to wonder if it was me who was hopelessly incompetent. Inexperienced yes. I also got to the stage of dreading switching on the LX200 and pressing the hand box buttons not knowing what might happen. Fortunately even although it’s now 19 years old I have not done much fast slewing. Now, like you advise, I perform a single star polar alignment then manually creep up on the unsuspecting target perhaps with a final auto-find when within a few degrees. I seek relief from the trials and tribulations of the LX200 with my 12″ Dob which is fun. I saw your 19″ Newtonian in ‘The Modern Amateur Astronomer’ book which I bought some years ago. It was a huge beast. I also saw your troublesome LX200 12″ in ‘More Small Astronomical Observatories’. Oh my, Scalextric motors. I know them well. Like many youngsters growing up in the 1960’s I had a Scalextric set (50′ circuit) and regularly had to replace the plastic gears, clean the commutator with a pin and replace the carbon contacts. My father had established a model/toy shop and with him being a qualified electrical fitter gave advice to me and fixed all the wonked out cars after Christmas – which were usually filled with hairy carpet. They were frail little things and the gears (and motors) did not last long if mistreated even mildly. Definitely not appropriate for putting in a telescope and making them whirr round at enormous speed. What were Meade thinking.
I’ll fiddle around a bit more with polar alignment and PEC training and then go for stacking. 30 secs works ok for the brighter deep sky objects. I attach a recent M31 image using the 60mm refractor – 21No, 30 sec exposures – possibly with dark frame subtraction (I’m learning the software) but with an unclean primary. The Ultrastar camera is good – a smallish chip and perhaps more of a guide camera – but simple to use and give good images.
The LX200 and webcam (Toucam Pro ii) worked ok for me back in 2009. I attach one image of Jupiter taken on 22nd August 2009 at 23:08hrs. Equatorial diameter 48.77″ and altitude 66 degrees. Seeing was very good. Image taken from location 35 miles inland from Cape Town. Registax software used to extract and build image. Fortunately I managed to find my old AVI video files so I can have another go at processing.
I have some horrendous AVI files which shows that sky ‘wobble’ can be worse than mount wobble. I will have a look at the option of a new mount in the near future. As an aside. An LX200 lift damaged my spine in 2007. I’d been going to the gym for 3 months was fit and relatively light in weight (for me) – mere 13 stone. A straight arm lift of the telescope from the wedge and bang the disk bulged. A horrible and painful 3 days spent lying flat on floor followed by a dead foot/leg for 6 months. Even now one leg is weaker than the other. So I can vouch for the advice ‘beware of heavy telescopes’.
On PHD it’s not important. It’s just another piece of software for me to fiddle around with. It’s usually the drivers and comms protocols that confound me. I’m not an electronic/software person (I’m a civil engineer – geotechnical) so I struggle a bit with the acronyms. Also modern guides are a far cry from Airfix instructions or Haynes Workshop Manuals.
Your Paramount and C14 sound fantastic. A really high quality system indeed. That’s a real BMW plus plus set up. My Dad had a Morris Marina. Worse car ever he said. I drove it. Oddly light and erratic. Yup – wobbly like an LX200 mount/drive. Not like the old Austin Maxi he had previously – stable yes – but that gearbox was beyond a joke – stirring cobbles – impossible to engage first gear – three attempts minimum needed – embarrassing at traffic lights.
I will persevere with the short exposures and stacking approach with as good a tracking I can manage with the LX200. Tonight looks promising so I might have another go at M31 with the cleaned up primary on the 60mm.
Cheers, Ron
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