CGEM DX 1100 vs CPC DX 1100 HD
Posted 02 June 2014 - 01:37 PM
I am considering purchasing either the CGEM DX 1100 HD or the CPC DELUXE HD. I intend to use which ever I choose primarily for visual, but as many others have mused I have not ruled out AP sometime in the future. This reason alone would not eliminate the CPC. Two other things bother me more about the CPC (I owned one 3years ago) are the weight of lifting the one unit OTA combined fork mount, and the cord wrap issue. The solution at the time was to buy the Starizona battery that rides on the mount, albeit awkwardly. What I like about the CGEM is the fact that the mount and OTA are separate. This would make it easier to lift, carry and transport. Here is the sticker for which I am seeking advice. How much higher is the platform of the CGEM mount when attaching the OTA than attaching the CPC fork mount/OTA to the tripod.
Posted 02 June 2014 - 05:20 PM
"Thank you for contacting Celestron Technical Services. I would be happy to help you out. If you have the leggs full collapsed on both the CGEM and the CPC tripod, then there would be a difference of about 18 inches. The CPC tripod you would have to lift the CPC about 31inches while the CGEM you would have to lift the telescope about 49inches. With the legs fully extended then those numbers change CPC is 46inches, while the CGEM is about 70.5 inches, there is a much bigger difference when fully extended. I hope this helps.
Posted 02 June 2014 - 06:56 PM
Maybe you've used one and are comfortable with it - if so more power to you. But those two things (and a deemphasizing of long sub photography) are what led me back to a fork.
Posted 02 June 2014 - 07:11 PM
" The CGEM DX wouldn't suffer from the cord wrap because of where the plug is located, you would only see it when you have a ALT AZM mount on a wedge."
Posted 02 June 2014 - 07:48 PM
I'll have to see if I can find a photo of the CGEM to jog my memory (or if it's the same configuration as the AS-GT5 I can look at that). I will admit I was thinking mostly about accessory cords - camera, auto guider, focuser, etc., but I recall the power cord being in the mix for both the AS-GT5 and the CGE. However, at the moment I can't recall it well enough to be willing to contradict Celestron's statement. I'll see if I can get a quick look in case that helps you.
Posted 02 June 2014 - 08:07 PM
As for weight, setup and cord wrap, I don't see any real advanbtage either way. Both mounts are about as easy to set up, and the Starizona battery eliminates any cord wrap issue on the CPC, which is really not a factor on the GEM, since the power plug is not on the part of the scope that moves.
Posted 02 June 2014 - 08:25 PM
1. will you set up and tear down every day? And how close is your observing location to where you have the telescope stored if you do not have semi-permanent setup?
2. visual beginning and then AP maybe in the future. This issue is I think secondary to #1 above.
Lets tackle #2 first.
As others have said the CPC is far superior design for visual observing. No contortion necessary and initial alignment is much faster in Alt-Ax mode. Many people will say the GEM is better for AP at some point in the future. BUT if you buy the HD wedge, then the CPC in EQ North mode is comparable to the CGEM in terms of tracking accuracy and imaging, maybe the CGEM DX is a bit better in terms of wire wrap, imaging near polaris and potentially better tracking in terms of non guided exposures. Guiding, I think they are both comparable.
Ok back to #1
If you do not have an easy and nearby observing location, then the CPC is a problem. before I had my CPC semi-permanent setup I had it in the garage and I would roll it out on small piano casters ($10 each!) to my driveway - i had it stored in the garage. This was super easy and took all of 30 seconds. IF you have to set up farther away, maybe over grass or surface you cannot roll, then this changes the equation and I would lean toward the CGEM DX option. But overall, even in this type of situation the CPC fork+mount vs. the CGEM + tripod+counterweights + OTA is not that much of a difference.
Hope this helps
P.S. Oh one more thing... if this is going to be your only telescope, then I think the CPC wins by a little bit. IF HOWEVER you plan on buying more scopes in the future, and you will not be buying another mount... then the CGEM DX will be versatile
Posted 03 June 2014 - 06:22 AM
This is where the CGEM is going to get you. If you are starting out doing AP an 11" F/10 or 7(w/FR) is a beast to image with. Putting a small fast refractor is a lot easier on the CGEM. Also your first concern of the weight and height, I'm of average height and can easily mount my C11 on the CGEM saddle the weight of the tube is only 22 lbs. Not sure of the CPC mount-tube weight but as I get older I'm not sure I would be able to handle more weight lifting.
Posted 03 June 2014 - 06:54 AM
Actually the C11 tube is closer to 30lbs (27.5 + any extras like visual backs, additional finders, dovetail plates, etc.) but your points are very good. In particular weight - the CGEM breaks down into much lighter individual components. The largest piece of the CPC1100 (C11 + CPC forks/base) is almost 70lbs (68 + any extras) and it can be a real problem for many folks.
Ideally if someone's setup allows for it a set of wheels makes a world of difference in the ease and speed of setup (and directly affects the amount of time you'll spend observing).
Aperture fever and the desire to buy the "best" possible setup are very powerful forces on a new buyer and they both actually work against enjoying this hobby the most. The "best" scope is really the one that you're likely going to use the most.