In this section, I will cover some general techniques I use to aquire images through my 8"LX200 and Starlightxpress MX7C or SXV-H9 using Astoart.

    The Meade LX200 has the ability to point to any object in its database or directly from input of RA and DEC coordinates once aligned properly.  I have mine mounted on a permanent concrete pier inside a roll-off roof observatory I constructed in the spring of 2001.  Alignment of the telescope is critical and directly impacts pointing precision.  Several techniques can be used for polar alignment, but I have found that I get great results using the "drift method" where you point the scope at stars on the eastern horizon and directly at the meridian and measure the star's drift north or south over a period of time, then make the appropriate corrections with the wedge.  I won't go into detail on this as there are many great web sites which cover this topic.  Mapug is one such site with many hints and techniques covering Meade scopes.  See http://www.mapug.com  for more information.

    Once the scope has been polar aligned the initial time, it usually holds alignment very well.  I've only noticed that I need to tweak the alignment due to temperature changes from season to season due to metal contraction or expansion or if I remove the scope for maintainance. To do an initial alignment each imaging session only requires that I point it at an alignment star and press the "enter" button on the hand controller which syncs the scope to that star's position in the sky.  I always do this with the camera attached and operating so that I'm aligning the scope to the center of the ccd chip.  During subsequent moves to other objects the scope puts the object on the ccd chip every time!

    Even if polar alignment  is dead on, often drive imperfections and periodic error require the use of guiding for long exposure imaging.  With the MX7C and any of the Starlightxpress "MX" cameras this can be done two ways.  On way is to use a second dedicated "guide" camera along with a guide scope.  The other way is to use Starlightxpress's Star2000 guiding software and hardware.  I initially chose to use Star2000 due to the relatively inexpensive investment required.  Star2000 will guide my scope to near sub-pixel accuracy.  The weak link in my case is the LX200 drive system.  As is the case with many LX200 scopes, I tend to see fairly large and abrupt movements in RA due to inaccuracies of the worm gear system.  These usually amount to .5 pixels in either direction at f ratio's of 4-7 which easly shows up as slightly elongated stars.  I've found that I need to use guiding rates of 1sec in order to reduce these "fast errors".  For visual use the drive system is more than adequate but the ccd see's every move and the less movement the better.  One nice benefit of using Star2000 to guide is that I have the entire area of the chip to select a guide star.  I usually can guide on stars to 11th mag but stars around 9th mag give the best results.

    Using Astroart, I GOTO my object of interest, center it and take a 1 sec exposure all using 2X2 binning.  Any star easily seen can be used as a guide star. One can also guide on moving objects like asteroids and comets.  All in all, the Star2000 system does a good job with the LX200.  The main drawback is due to the chip design, only half of the chip is being used to expose the object, the other half is used for guiding.  This means that if I take a 10min long image, in reality it's only a 5min full integration.  It takes twice as long to aquire a set of images but time is something I have plenty of.  Some of the guide settings I use in the Astroart "telescope" settings box are (f6.3, x=6.0 pix/sec y=9.5pix/sec), (f5.9, same as f6.3), (f4.2, x=4px/sec y=5px/sec) the x axis reverse check box is selected and I use the "automatic dec backlash correction" option.  One more thing about guiding, some imagers have had better guiding sucess by weighing down the left fork arm of the telescope slightly, using homemade weights so that the drive gear pushes the telescope in RA.  I have tried this method and have also guided with no weights so the worm gear slows the fall of  the scope in RA.  I have not seen any difference in either method with my particular scope and am currently using it without any weight on the left fork arm.  

    In 2003 I bought a used SX MX5-16 to use as a seperate guide camera allowing me to spend all my valuable time at the scope exposing.  I use this camera either on the piggybacked Stellarvue SV78S or when imaging throught the Stellaruve, I guide with the LX200.

    I have a JMI NGF-S zero image shift focuser attached to the scope.  This focuser makes focusing a snap and I would highly recommend either a JMI or one of the other motorized crayford style focusers for imaging.  I've added extra cable length to the hand controller so that I can focus while sitting at the computer screen.  Using Astroart I set up the focusing routine using 2X2bw binning and 1sec images which seems to give the fastest update rates.  After  moving to my object of interest,  I select a 8-10th mag star by drawing a small box around it and select the focusing button.  I  focus to get the smallest FWHM and highest adu reading.  At lower f ratios there is a very slight difference in focuser movement between good focus and best focus.  On most nights I can get the FWHM down to about 1.2 to 1.5.  I also usually go from one side of focus to the other in order to make sure I have a good focus.  The adu readings will peak in the middle, then drop off rapidly on either side.  If the temperature is dropping rapidly during an imaging session, I find that I have to adjust the focus for every 1.5-2dec C change by tapping the "out" button on the hand controller.  This is due to contraction of the scope tube and other metal parts.  This can be done while guiding since the image does not shift at all.  It really helps to have a thermometer hanging on the wall near the scope.   One way to tell when the focus is changing is to watch the guiding box star pixels.  Usually with a good focus and good seeing the star looks like a cross with brightest pixel in the center.  When the focus changes the look of these pixels will change and become softer.  Seeing can also affect to look of the guide star so be careful and make sure its only temperature causing this change.  I can definately see the difference with a 2dec C change in temp.  I also use a "diffraction focuser" to reach a rough focus if I change f ratios from image to image.  Its quick and I gets you really close.  The key with using this method is to select a bright enough star and long enough exposure to see the diffraction spikes.  Usually I do this on my alignment star since they are very bright.  A 1 sec exposure usually works great.
 
 

    I have both the Meade f6.3 and f3.3 focal reducers.  Both seem to work fairly well.  The reducers are attached to the rear of the focuser and the camera attaches to the reducer thru a T fitting.  The f3.3 reducer seems the most versatile since with it, I can image with a variety of f ratios from 2.5 to 7.   Some coma is present at f ratios below 5.9 but it isn't too objectionable.
Addendum:  The meade 3.3 focal reducer does not work well with the larger chip of the SXV-H9.  Severe coma occures about 1/3 of the way out from the chip at the design distance of 55mm.  The Meade f6.3 reducer works well at a distance of about 100-115mm with slight coma along the extreme edges.