Jump to content



New Members
  • Posts

  • Joined

  • Last visited

Posts posted by Ianstraton

  1. I have an LX90 with a burned out motor. I have managed to remove the motor assembly but unfortunately there are no markings on it to indicate part number or any specifications of the motor. I called Telescope house but their service department is closed for the next two weeks so... Does anyone have any information about these motors? Does it actually matter what motor is in there? There appears to be an optical position monitor as part of the assembly so would this correct for any variance in performance of a replacement motor?

  2. ok I know I should have gone to this location while the comet was still bright but frankly I was too scared I would get robbed or worse...

    Anyway here is panorama (consisting of 15 subs) of the milkyway and comet lovejoy over Table mountain and cape town. The images were taken with a modded 550d 18mm lens and astronomik cls clip filter (I'll leave it to your imagination what the scene looked like without the filter... lets just say there aren't so many stars visible!) iso 400, f3.5, 25 second exposures. The subs were loaded into photoshop and merged using the photomerge tool then flattened to a single layer and cropped to remove the worst of the stepping produced by my shot selection.. the resulting image is presented here (reduced in size and converted to 8bit jpg to get it to a postable size, the 16 bit original is HUGE) as you can see there is a strong gradient emanating from the bottom left and overall the colours look a little strange but the main issue is just how faint the objects of interest are within the general glow.

    I have tried selecting out the mountain and city and processing the sky separately this sort of worked but the junction between the sky and the mountain ended up looking very very "fake" which was disappointing, I have also tried creating a star mask with the aim of dropping brightness of the sky background but I found that I couldn't separate the comet from the sky glow.

    Any processing suggestions would be welcomed..


  3. I recently upgraded to 64bit win 7 and now eqascom is giving me bizarre error messages when I try to load the drivers (see attachment).

    Is anyone else running eqascom on win 7 64bit? if so did you have these problems? If not can you do me a favour and have a look at what windows componants you have installed and tell me which .net frameworks you have installed?

    Thanks in advance!



  4. Thanks for the info on the meade goto, that's the sort of thing I was after!

    I did consider going down the reflector route but decided against them on the grounds of overall size, this thing has to fit into the car when loaded for a weekend away with the family, 130 starts to tip the balence too far..

  5. I have decided that it is too much effort to dis mantle and reassemble the observatory scope to take away with me on weekend trips. As a result I now need a new scope, it must be small enough to be easily transported, have a go to mount (alt /az is fine I don't intend to image with this scope) with a self contained power source and not overly expensive. I am mostly interested in DSOs so I have eliminated a small SCT/MCT due to their central obstruction and excesive focal length. So I think what I am after is a small and fast refractor.. My initial online trawl has thrown up the following scopes:

    1. Skywatcher star travel 80 auto (179.00)

    2. Meade ETX80 AT-BB achromatic backpack telescope (237.00)

    3. Skywatcher Startravel 102 SynScan Telescope (280.00)

    The meade has the advantage of a specially made carrying case included in the price (not sure if that is worth the extra 58 pounds).

    The skywatcher 102 has the advantage of an extra 20mm of aperture over the other two (is that worth the extra 43/100 pounds?).

    The skywatcher 80 has the advantage of being cheaper than the other two.

    So would anyone have any comments on the qualities of these scopes or suggestions of other scopes I should consider?



  6. Yes, I use this method with the main scope, the motor on the eq2 does have an adjustable speed but no speed scale, but thinking about it now i don't think it actually matters, the reason for 2x is that the stars end up pretty close to the starting point after a one minute out, one minute stopped, however if the motor speed is quicker or slower all that happens is the star ends up finishing long or short compared to the start position which could make star id difficult in narrow FOV images but in widefield shouldn't matter much as the whole trail will be visible in the picture....

    (or am I kidding myself again?)

  7. I have an eq2 which I am planning to convert to use for widefield photography, the mount has fixed setting circles so I wondered if a quick shortcut to polar alignment would be to set the circles to the position for a known bright star like vega and then adjust the alt az screws until that star is central in the camera view finder.

    will this work or am I kidding myself?


  8. Sorry! I doubled the tube's focal length and halved the eyepieces when I did the calculations, daft mistake...

    There are good zooms and bad zooms, a good zoom can out perform a poor fixed length eyepiece but a good fixed will be better. the problems with zooms tend to be more noticable at the short end but that said my hyperion zoom is at least as good as my set of plossl's to the point where I rarely use them now except for the wide field 32mm eyepiece (the zoom only goes to 24mm)

    If you are considering buying 2 or more eyepieces have a look at a good quality zoom as well.

  9. fair enough! but if you already have a barlow then your 10mm in the barlow will give you 300X maginification which is the limit of what your scope can achieve anyway so there is no point in buying a shorter focal length eyepiece.

    the smaller focal lengths also tend to have smaller apertures at the eye and much shorter eye relief (unless you are buying very expensive eyepices) both of these reduce the comfort of use, and if (like me) you wear glasses you may not be able to get to the focal point at all. In my box of eyepieces I have a 5mm eyepiece and I think I have used it once....

    two eyepieces I would consider though would be:

    1. a zoom lens (like the baader hyperion) which allows you to zoom from wide field to high magnification continously without having to change eyepieces, these cost about the same as ok normal eyepieces but are much more versatile.

    2. a low power with a large apprent field of view, generally not cheap but the results are spectaular!

  10. I'm not really bothered about trailing, I know how to deal with that, what I was wondering about is whether the inherient distortion of the lens would make it impossible to stack images given that unless the camera is tracking the stars will change position in the frame from shot to shot, this plus the distortion will cause apprent changes in geometry, the real question is: can DSS recognise and work with these distortions?

  11. The buble levels in the eq mounts are generally not good, I have an eq5 with a built in bubble mount that is about 15 degrees off! However that said getting level is not hugely important, it does complicate getting polar aligned a little but once aligned it makes no difference to the tracking or slewing of the scope.

  12. My local camera shop has an 8mm fixed lens on for a bit of a bargin price and I am sorely tempted, on my camera it would provide a 167o field of view. However being a fisheye lens it is inevitably heavilly distorted, so my question is: is it viable to leave such a lens snapping away all night and then use deep sky stacker to stack the results or would it have to go on a driven equitorial of some sort to prevent field rotation?

    any thoughts or experiences welcome...

  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use.