Items that make the amateur astronomer's life much easier.
A simple device that when placed at the front of the telescope shows very accurately when the 'scope is properly focussed. I use it together with the excellent freeware Bahtinov Grabber.
Howie Glatter Laser Collimator
Originally manufactured and sold by Howie Glatter, this two-part laser collimation system was taken over by Starlight Instruments after his death but it's legendary build and performance have not been compromised by that move. The basic laser instrument (silver) is inserted into the telescope's focuser and used to adjust the Newtonian secondary mirror by centering the laser beam on the primary mirror's center spot. Thereafter the basic unit is inserted into the TubLug (black) and the combination is inserted into the focuser where it is used to adjust the primary mirror. That is done by centering a reflected image of the primary mirror's center spot over the central hole in the circular white screen displayed within the TubLug's cutout section. There is no better system for achieving perfect collimatiom.
PoleMaster Polar Alignment Camera and Software
A very effective tool for polar aligning equatorial mounts. It fits onto the mount using a supplied bracket and lets you achieve very accurate polar alignment in under 10 minutes.
SkyWatcher Wi-Fi Adapter