Celestron’s New Heavy Duty Pro Wedge
Last year, Celestron announced the introduction of a “new Heavy Duty Pro Wedge”, especially for use with the CPC series of fork-mounted telescopes. The non-heavy duty version which is replaced had been marred by horrible reviews, flimsy parts, and amazingly, competition from various firms which apparently knew how to make good products (such as Mitty). So, when they claimed a new design, more rugged, durable, and based on their learnings from the previous wedge, I couldn’t help but investigate.
To be sure, this version is big and heavy, but it pairs very nicely with the CPC 1100! The documentation was a little bit confusing for me; “front” and “back” was not well defined and mixed me up a bit. However, it comes mostly assembled. The trickiest part was dealing with the latitude adjustment bar and required a bit of finesse to allow the wedge to open up.
There are also four bolts on each side of the wedge to allow for centering and help out with balancing the scope. Given that my scope has a lot of additional accessories bolted on to it, I simply eyeballed it and slid it back one notch. It looks a little bit odd on the side: only three of four bolts are now securing the wedge to the base. However, this doensn’t seem to be an issue and when mounted, the base and tripod are indeed very well stabilized and balance. It would be possible to tip over, but it would require and intentional push.
Attaching the wedge to the tripod base was not difficult but wasn’t handy either. There are three screws which one uses an allen wrench to affix to the tripod. These are the same three holes in the tripod one normally would put telescope base – although tightening the bolts sufficiently required many turns of the wrench. Unfortunately, the wedge was in the way and made turned it into a large number of 1/8 turns. Whenever I have to repeat something so many times to get a bolt screwed down, I always wonder if I’m doing it right…
Once The wedge was finally together on the tripod, the real moment of truth was getting the scope on the wedge. Given that my latitude is nearly 48 degrees, there is quite a tilt to the wedge making for some really awkward positioning. Luckily, the CPC has two place to grab; one on the base of one of the fork arms, and another handle in the middle of the other fork arm. This latter handle is the one which comes in super mega ultra handy: without it, I don’t think it would be possible to mount with one person! I place one screw-knob (that comes with the wedge) into the bottom of the CPC’s base aligned with this handle. Then, I lift the entire scope with this one handle and brute force bring it up – over 80 pounds of stuff – and get the top screw engaged with the notch on the top of the wedge. I’m pretty sure a lot could go wrong in this step, from the bolt being too lose or breaking in some capacity, or simple missing the notch and thinking I found it – but so far I haven’t died yet – probably the paranoia of something going wrong is keeping me alive!
Once this top bolt is there, before tightening it, I place the other two bolts in and get them well in place. It helps to get things snug by lifting the far end of the scope upwards while standing behind the scope – else everything is pulling away and screwing the bolts in is very difficult. Once fully attached, things seem pretty solid. Alt/Az adjustments are a breeze and easy to make very fine corrections. In fact, they seem too easy given the amount of weight on top of them. It is much easier than on the CGE Pro.
At this point, you should be wondering how to do the polar alignment. There is no polar scope option, and no obvious mechanic for lining up the scope with the Earth’s axis. The answer is to use Celestron’s All Star Polar Alignment (ASPA) routine. However, for older CPC users, it is necessary to update the handset with a newer version of the firmware for this feature! In addition to downloading some software, you also will need the RS232 cable for the handset. And, if you have a newer computer, you might also need a USB to RS232 adapter, which turns this simple process into a multi-step store visit. As far as software goes, the NexStar site has a wonderful tutorial to update firmware. In my case, selecting the CPC series of scopes from Celestron takes you to their CPC Downloads Page which contains the Hand Controller Firmware needed. Cables aside, this process turned out to be much simpler than I was expecting and I didn’t have any problems at all.
Before performing ASPA, I do an AstroKev Eyeball Align (AKEA). Essentially I put the scope out and point it’s axis generally towards the north pole. I find that walking back about 15 feet and scrunching down to the ground and looking to see where Polaris is and how well pointed the scope is works pretty well. Alternatively, using the iPhone compass works well also. Next, I used an EQ North Two Star Align (for some reason, my scope doesn’t have both the “index markers” required for the “EQ AutoAlign”). This certainly is the easy part. Next comes the ASPA – which is documented in the CPC Manual starting on Page 30. This process sounds complex, but it is really quite simple: Have the scope slew to a bright star (in it’s Named Stars database), center it with the hand controller and press Align. The scope will then move again as if it were pointing back to the same thing were it properly polar aligned. This second time however, center the star using the alt/az controls, not the hand controller! The manual suggests updating the original stars used for the EQ North alignment. I skipped that step and my GOTOs were indeed off slightly; next time I won’t!
My first target of the night was M42, the Orion Nebula. A longtime favorite, this nebula is spectacular both in wide field images and narrow fields. In this case, I used the CPC’s native and full 2800mm f/10 to image. Way oversampled, but beautiful nonetheless. This image was built from 5x 5 minute exposures, autoguided with PHD Guiding and the ST80. Processed in Nebulosity and MaximDL.