First light (just!) CPC 800

[Andymarrison]

I took delivery of my very first "proper" scope, a Celestron CPC 800, from FLO on 20 April. It arrived in two rather large boxes - one containing the tripod and the other the scope mounted on its fork arms. The scope was very well packaged in a closed-cell foam type of material which should come in handy for future storage in a suitable case.

The tripod is very sturdy indeed, with 2" diameter stainless steel legs and a substantial steel mounting plate on the top with built-in spirit level. A heavy steel accessory tray is provided and also acts as a spreader for the tripod legs - bracing it against the legs is achieved by tightening a bolt on a tension rod that runs through the centre of the tray and is fixed to the top plate of the tripod.

The tripod needs to be sturdy because the scope together with its motorised fork mount weighs in at about 3 stone (19kg). In spite of that it's surprisingly easy to move around because of the two very well placed carrying handles - one attached to the side of one of the fork arms and the other a moulded hand hold in the base of the other fork arm.

Attaching the scope to the tripod is very simple - a raised steel locating pin in the centre of the tripod mounting plate fits into a corresponding hole in the base of the fork mount, then the fork mount is rotated until the three slightly raised mounting points on its base drop into the corresponding recesses in the tripod plate. The mount and scope are then held in place on the tripod by tightening three "captive" securing bolts. This whole process is very quick and takes only a minute or so.

The tripod remains rock steady once the scope is attached - perhaps not surprising as it's the same tripod (and fork mount), that's used for the two larger scopes in the CPC range - the 9.25" (26 kg) and the 11" (29 kg), so it's more than up to the job.

Power is 12V DC via a cable plugged into the base of the fork mount, and since no adaptor is provided with the scope you'll need either a 12V power tank or equivalent, or a mains adaptor.

The scope handset also plugs into the base of the fork mount and then sits in a holder on the side of one of the arms - the cable is rather short, though, and I might look into extending it by a foot or so in the future to allow for a bit more movement whilst observing.

On "power on" the handset provides clear instructions on how to align the scope (the manual is pretty good, too) and I went for Celestron's SkyAlign method - first the scope tries to find a GPS signal, which can take a good few minutes first time around, and then displays what it thinks is the current time. I had the same experience as reported by a number of other users in that the scope displayed the time as if it was still on Pacific Standard Time! I carried on regardless and this didn't seem to affect the alignment process or the accuracy of the goto functions later, but I've since changed the time zone through the "Scope setup" menu (thanks to cfpendock for that tip!) and the time looks spot on now.

Once the GPS data has been confirmed, the scope asks the observer to centre three bright objects first in the finder scope (for which the computer sets a faster slewing rate) and then in the eyepiece (slower slew rate automatically selected). Any three bright objects can be chosen, though the manual notes that the best accuracy will be achieved with objects that aren't too close together, nor on a straight line. Since I was dodging lots of clouds, I picked the Moon, Jupiter, and Mars - not ideal but beggars can't be choosers!

I actually spent quite a few minutes looking at each of the alignment objects - the moon looked fantastic at 80x (24mm Baader Hyperion eyepiece) - an extremely crisp image with lots of contrast, and the crescent of Venus very clear and sharp in spite of the planet occupying only a very small part of the field of view at this magnification.

After the third object has been selected, the handset thinks for ten seconds or so before confirming alignment. At this stage it's possible to scroll through the names of the three objects the scope thinks we're chosen to check that it's got it right, which in my case it had.

Selecting objects to view is then extremely simple - the handset can use all of the common catalogues (Messier, NGC etc) and also has options for planets.

I chose the M3 globular cluster as the first test for the goto, and sure enough the scope put the cluster very close to the center of the eyepiece field of view (using the same 24mm eyepiece). With averted vision I could pick out some graininess from the individual cluster members (I wasn't very well dark adapted due to staring at the Moon for several minutes!) but to be honest the conditions weren't ideal for making a judgement about the performance of the optics on this DSO (M3 was unfortunately very close to the street light near our garden and other areas of the sky covered by cloud).

Unfortunately my evening of observing was cut very short (only 20 mins or so of viewing) due to the clouds rolling in, but first impressions are of an extremely well engineered scope and mount with a well thought through design and excellent optics, based on the limited opportunity I had to test them. I'm planning to use the scope for visual observing, and based on its first outing I'm extremely pleased with my purchase and looking forward to using it again, if it ever stops raining.

[michael.h.f.wilkinson]

Congrats on your new scope. I have the same optics sitting on a different mount, and really like it. C8 optics are really nice. It is hard to get a better compromise between aperture and portability that this optical tube. I hear the CPC mount is very good. I bet the scope will give you a lot of pleasure in years to come (mine is 15+ years old, so they last!)