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Cosmic Geoff

Celestron CPC800 First Light

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I recently acquired a used CPC800 SCT. I thought a 'First Light' report might be of interest.

First impressions: the tripod is a heavy duty affair with thick legs, a folding lower spreader and a big cast alloy eyepiece tray/steady.  The OTA/fork assembly (not separable) is very heavy (21Kg/44lbs) but has a couple of grab handles. You need to be fit to handle this. ? (I was seriously tempted not to go ahead with the purchase after trying the weight.)

With the legs retracted it is just possible to pass the tripod through a standard doorway, but it is just as easy to pull up the lower spreader and carry it folded. It is much heavier than a C8SE tripod but more comparable with a EQ5 tripod in weight.  Once in position, I checked the level with the handy built-in bubble level and left it.  I forgot to screw up the eyepiece tray/upper spreader but I don't think this made any difference. 

Scope stored on a table with faceplate down and rear handle uppermost. Took the weight with my left arm, elbow fully bent, forearm vertical.  Got it on the tripod which took the weight till I got the base to drop over the centre pin, spun it till something clicked into place and then did up the three thumbscrews.   I would not try this with an equatorial wedge unless I had a helper.   Celestron also sell a CPC 9.25 and CPC1100 - if I had one of those I'd need a sheerlegs or a brawny assistant.?

Fitted the visual back (same as C8 SE), prism diagonal (same as C8 SE), straight-thru 50mm finder, handset (Nexstar+) and handset bracket which holds it facing rearwards (a handy feature not implemented on the C8 SE). Fitted a 25mm X-Cel LX that came as an extra.

Connected my new lithium powertank and its DC cable, and powered up. It comes ready (CPC Ready) very quickly. Selected 2-star auto align - it whizzed past a time display showing the time ahead of my watch by 1 hour - more on this later.  Aimed at Arcturus and afjusted the finder aim. Selected Capella - it nearly got there and then blackout!  The cable had snagged and pulled on the plug. I ran the cable through the side handle on the fork and tried again.  (It appears that the CPC's supplied cable has a locking ring and the other end has a cigarette lighter style plug.) Capella ... Arcturus .. aligned.  Told it to find Mizar (named star menu).  It did. 

Also found M48, the Ghost of Jupiter planetary, Gamma Leo (split ), 54 leo, 88 Leo, 90Leo.  The scope appears to be collimated and resolution OK.  GoTo is just accurate enough to drop doubles into the bottom of 9mm X-Cel Lx field.  Even at 200x and a gusty night the view is rock steady. A pier mount could hardly be stiffer than this! And no obvious backlash in use (unlike C8 SE).

Fiddled with the menu, found the GPS is obviously working, and the time set for daylight saving.   Corrected it to standard time. GoTo still works.

Teardown: tube horizontal, power off, tube cap on, diagonal off, handset and bracket off, left visual back on and capped it, loosened clutch to point tube straight down.  Got OTA/fork assembly off and back indoors on table, twirled it into position.  Folded up tripod and carried it indoors. I would not try carrying the tripod and scope together.

Verdict: Very solid mount should be good for planetary imaging.  Some nice features not on C8 SE, otherwise same optical performance.  Alarming weight.

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I have the same scope.

Weight issue might come in if I had to carry it far, but I have a viewing spot not far from the house (only point that blocks the street lights).

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I am about 5'6" and average build but have managed my CPC 1100 alone (though I don't know for how much longer). In the house I remove the OTA + fork from the tripod by carrying it using the side handle and recessed hand grip on the other and put it on a table. Then I take the tripod outside alone followed by the OTA + fork. I need to support the OTA + fork assembly on the front of my body because it is too heavy for my arms alone. I fear one day this process may not end well ?

Cheers

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I have just bought a flatbed trolley from B&Q to aid in moving my CPC800.  With a crate placed on top of the flatbed and the fork assy stood on that,  I just have to wheel it with one hand while steading the OTA grab handle with the other.  More sophisticated or customized arrangements are possible but this will do for now.

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