Going away on holiday has always been problematical for a number of reasons. If it’s clear the big scope is back home and tucked up all nice and cosy in the observatory 🙁 I certainly wouldn’t want to have to remove the G11 off the pier and haul all my kit away with me, so usually end up taking a pair of 10×50’s. The binos are nice and portable and also serve for daytime terrestrial duties but, for anything but the brighter galaxies and clusters, don’t have the aperture required.
I did contemplate taking the TMB80 and mounting this on my Carbon Fibre tripod . But with the Alt-Az camera pan head, it’s next to impossible to move and then lock onto the object being observed without the scope sagging slightly and moving off target.
There are a number of rather nice Go-To Alt-Az mounts out there, but they are quite pricy, require a handset and batteries and are a bit off a faff to set up, so I rejected this type. All I really need is something that can be hefty enough to be stable; but be easy enough to point to where needed and allow larger and heavier scope or scopes to be fitted in the future for things like Star Parties. After a trawl on the net, The Altair Sabre seemed to fit the bill nicely.
While not exactly cheap with all the accessories I added, it has proved perfect for the job. Made in Aluminium, the assembly sits on top of any tripod with a 10mm treaded head. While I could have saved £100 and used by carbon fibre tripod, I decided the weight of their Stainless Steel jobby would make for a much more stable platform. The ALT and Az axis bearings feel as though they are running on ‘Delrin’ type bearings and with the adjusting knobs loosened right off, allow the scope to be moved where needed and stay there. There is just the right amount of friction in these bearings to make the action feel like a really well made Dobsonian. In practical use when focusing you need to apply a little friction to both axes by tightening the knobs a tad so the scope doesn’t move off target. The amount of friction you get is very controllable, so can be fine tuned to suit your setup.
The horizontal bar is offset, which would allow a large scope to be fitted, which will when clear the tripod legs when viewing near the Zenith. I did buy the Stainless Steel counterweight shaft and two counterweights just in case. For the TMB 80 these are not needed, but Altair Astro say they have fitted a 250mm Newtonian with the appropriate counterbalancing and found the set up perfectly useable.
The scope end of the shaft is fitted with a dovetail clamp, which will accept the scope mounted Losmady dovetail plate. The tripod comes with a spreader bar, but I haven’t found this necessary. The whole thing can be set up and ready for use in less than a minute. So how does it perform in use?
Well very nice thank you. The scope can be aimed like a gun to get me into the ball park, then with a 40mm eyepiece fitted, I can scan the area to nail the target. With the 18mm Super Wide Angle fitted, the scope could be easily and smoothly nudged as the object tracked through the field of view. I did find that things got a little too jerky in Azimuth with anything less than less than my 9.7mm Plossl though. Maybe a bit of counterbalance weight at the other end of the Azimuth bar might help this, so need to experiment a little further on this.
All in all, I’m really happy with the set up. It doesn’t take up too much room in the car, can be set up quickly, and for all but the shortest eyepieces, is a doddle to use. It also acts as a very good terrestrial mount , so doubles up for something like for Bird watching (or spying on the neighbours 🙂 ) during the day.