Home Gallery Tutorials Equipment About




Celestron 80mm SLT Series Optical Tube

    If you're going to try astro-photography, a good guide-scope Celestron SLT optical tubeis is pretty much a neccessity, unless you choose to use an off-axis guider.  I lucked up on a used optical tube off of a broken Celestron SLT series go-to mount for about $60 bucks.  It had a couple of open mounting holes on the side, which I readily plugged with a couple of screws of the same thread type and it had a cheap plastic focuser that had too much play in the focusing tube that needed replacing, which I replaced with a GSO dual-speed Crayford focuser.  

    The Crayford focuser has a shorter focusing tube than the original, so I had to add a 35mm extension tube to be able to achieve prime focus. With this scope's focal ratio at F/11, this puts the guiding magnification close to the same as the imaging magnification, which gives very good tracking results, necessary for deep sky photography.


Celestron 80mm Wide-field Refractor

    At first, I tried using an Orion Express short-tube doublet refractor attached as a guidescope on the C9.25" SCT Celestron 80mm short tube refractoroptical tube.  But, it was considerably heavy and also created "flexure" when trying to image.  Next I tried using the SLT (above) as a guidescope, but due to the length of the optical tube, it didn't work too well either.  Finally I ran across this extremely light, (only 2lbs) 80mm F/5 achromatic refractor.  It fit the bill perfect.  It has excellent optics for an achromat, the focusing tube is very snug and when fitted with a barlow, it does very well as a guidescope.  Consequently, the "ten frame mosaic" image in the Lunar Gallery was taken through this scope.  All said, this has made a nice little guidescope.


Celestron 80mm F/7.5 Guidescope


    After acquiring the CGE Pro mount, to better improve my tracking capability when using the C9.25 SCT for astrophotography, I chose to upgrade to Celestron's F/7.5 80mm guidescope.  It's also light and has excellent optics for an achromat.


Orion Starshoot Autoguider


starshoot autoguider

    This little piece of equipment, along with the PHD guiding program has made life much easier.  It is extremely easy to use (and relatively inexpensive).  Just attach a cable from the camera to the autoguide port on the mount, open up the PHD guiding program and make a few setting adjustments, let the program calibrate for tracking adjustment and BAM!  You're ready to go.  The only hard part is finding a star to use as a guidestar.

For more info on the Orion Starshoot autoguider see the link below.



Home Gallery Tutorials Equipment About



Copyright 2010  All Rights Reserved