Celestron 6.3 reducer

[Dogstar45]

Hi, Just getting started out here and trying to avoid mistakes with equipment selection! I am getting a Celestron CPC 925.

Given that this is f10 I want to use their 6.3 reducer to increase the FoV.   Can anyone recommend a 30mm eyepiece that is compatible with this? I read somewhere that some eyepieces with wider apparent FoV's in turn have their own FoV restricted by the reducer. Which would rather neatly defeat the object of the exercise! I have read good reports about the Pentax XW 30mm.

Thanks!

[Cosmic Geoff]

Rather than trying to make the CPC925 (a very heavy instrument, BTW) into a widefield one, have you considered complementing it by buying a cheap, widefield, Dobsonian? It would cost little if any extra, and give you a grab'n go for the occasions when you don't feel like wrestling the CPC925 out of storage and spending half an hour erecting it.

[Louis D]

7 hours ago, Dogstar45 said:

Given that this is f10 I want to use their 6.3 reducer to increase the FoV.   Can anyone recommend a 30mm eyepiece that is compatible with this? I read somewhere that some eyepieces with wider apparent FoV's in turn have their own FoV restricted by the reducer. Which would rather neatly defeat the object of the exercise! I have read good reports about the Pentax XW 30mm.

You'll get vignetting trying to use a 6.3 FR and a widest field 2" eyepiece at the same time.  TANSTAAFL.  You can either maximize your TFOV with the 6.3 and a 32mm 1.25" Plossl or via a 40mm SWA like the Pentax XW-R 40mm in a 2" diagonal without FR.

If you really want to try combining the FR with a 30mm, 70° eyepiece, I would recommend the 30mm APM UFF or one of the other 5 or 6 rebrandings of it.  It has better correction, a flatter field, and is more compact, lighter, and less expensive than the 30mm XW-R.  However, you are likely to see some vignetting.

You're never going to get decent wide field views even with the 1500mm focal length using the FR.  A 72mm ED refractor or similar would nicely complement the 9.25 SCT.  You might even be able to mount it as a super finder with the SCT.

[Dogstar45]

Thank you both for your replies. I am reconsidering the idea of the CPC   - it is starting to feel impractical.  One alternative suggestion has been to couple a C11 XLT optical tube with a Skywatcher AZ-EQ6GT mount.  Does that sound like a good set up for solar system viewing? And then I will definitely need another telescope for deep sky objects!

[Cosmic Geoff]

12 hours ago, Dogstar45 said:

One alternative suggestion has been to couple a C11 XLT optical tube with a Skywatcher AZ-EQ6GT mount. 

That would work, but you don't need an equatorial at all for solar system viewing and imaging.  An alt-azimuth mount is much less bother.  On the other hand, for a C11 the choices of alt-azimuth mount are limited...  The AZ-EQ6 GT isn't a lightweight mount, but you would have the option of putting a cheap Newtonian or a refractor on it for widefield, or using it with an imaging scope at some point.

You can get the C11 as a CPC1100 for solar system viewing and imaging, but that is even heavier than your first choice and best kept in an observatory (or on wheels). 🙂

Personally, I'd suggest that you make a 'beginner' sized scope your first purchase, rather than jumping in with a costly, awkward to handle and more specialised setup. There is no rule that says you have to own just one scope, and your interests may change. 🙂

[Dogstar45]

4 minutes ago, Cosmic Geoff said:

9 minutes ago, Cosmic Geoff said:

the option of putting a cheap Newtonian or a refractor on it for widefield

 

The idea of one mount and two telescopes is very appealing! A previous responder suggested a Skywatcher ED 72  for widefield. That seems like a good combination of telescopes, but you think an 11" too big?  Alternatives being 8" or 9.25"

[Cosmic Geoff]

14 minutes ago, Dogstar45 said:

but you think an 11" too big?  Alternatives being 8" or 9.25"

That's entirely up to you.  The bigger the scope, the heavier the subassemblies are, and the prospect of setting it up and taking it down at night becomes less appealing, and the bigger the bill when you fumble it and drop the OTA onto concrete.  Personally I would not want anything bigger than an 8" in the CPC range, or a C9.25 if the OTA and mount will separate.  Check the listed weights of these items, and if possible go see them in a showroom.  Note that you need some way of holding onto a fat SCT OTA, and if working alone you need one hand  to do up the clamps and one or two hands to hold it in place...

Also note that these big expensive SCT outfits do not hold their new price well if you decide to sell them on, and you would be lucky to recover much more than half your initial outlay if you decide it's not for you.  THe AZ-EQ6 should hold its value better.

[Andy ES]

I’ve been using a CPC925 for about 9 months and have been very impressed with the quality and performance. Lunar and planetary views have been breath taking.

The goto function is very accurate and the alignment process can be achieved in about 5 minutes once you have had a bit of practice. I don’t use the finder scope as I find a red dot finder or Telrad much easier to find alignment stars with. (Eyepieces in use as below)

YES it is a big lump but I move it on a wheeled dolly and then is fairly easy to mount onto the tripod, again it needs a bit of practice to land it . 

The tripod is superb and very stable. I get almost zero wobble.

again it’s not wide field, but don’t confuse that with not being able to view DSOs, as it can do this but without the “space walk” experience.

I highly recommend the CPC925, but don’t get one if you have got a history of bad back problems. 😄

I think Ed Ting on uTube rates the C9.25 optical tube (not the CPC version admittedly) as his second scope he could not do without. 

 

[Dogstar45]

I'm definitely leaning towards the C9.25 OTA only because of the CPC's  weight  and I do like the idea of the AZ EQ6 double mount.  Thank you all for your suggestions, the equipment choices facing a beginner do take some sorting out. First was the realisation that one telescope is not going to do everything!