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CG-5GT or wait

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#1 wsuriano

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Posted 10 April 2009 - 03:17 PM

I'm seriously considering buying a CG-5GT mount (getting a pretty good price) mostly for AP. I'll use an Orion 120 mm f/8.3 (OTA=9 lbs) as a guide scope with a Meade 5000 80mm APO (OTA= 6.2 lbs) mounted atop the Orion as an imager in rings. Add a couple DSI cameras and you're basically there. Will this set up work for me? My other option is to save a bit more (actually quite a bit more) and go with either an Atlas or CGE. Eventually, I'll want to replace the Orion with a higher quality 120-127mm scope that can double as a quality imager. This will add some weight, but probably still well within the advertised limits of the CG-5.

Bill

#2 Luigi

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Posted 10 April 2009 - 03:40 PM

I haven't done any imaging myself, but from I've heard here, up to about 20 lbs total load, the CG5 works reasonably well. Keeping the tripod short and using a stiff dovetail (or moving the OTA rings closer together) can help with stability.

#3 therocksal

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Posted 10 April 2009 - 05:46 PM

I'd buy a bigger mount for all that and for the future...CGEM would be my choice.

I'm waiting to see how the custom wedge will be for the mini tower..I'd love one of those for A/P so I wouldnt have to fool around with a GEM

#4 Al Canarelli

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Posted 10 April 2009 - 06:10 PM

I bought my Advanced GT for imaging and it's wonderful for that purpose...as well as just plain viewing. I use a Canon DSLR and get great results. I suggest that before you go any further, you should buy the below listed book which comes on CD. It has served as my bible and I'm sure will also help you. It tells you what equipment to buy, where to buy it, how much to pay for it, how to use it and why to use it...plus much, much more! This is the best 30 bucks you will ever spend and the author is not my brother. www.astropix.com

#5 mclewis1

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Posted 10 April 2009 - 06:10 PM

Bill, I'd get the best deal you can on a CG-5 now instead of waiting on a larger mount ... the experience you'll get from actual use will be very valuable.

I would also not use that 120mm scope as a guide scope ... it's simply too much dead weight that's not doing anything for you. For a nice lightweight and inexpensive autoguider get a used 50mm finder and adapt it for use with one of your DSIs (lots of threads here on CN about how to do that). That in combination with that nice 80mm APO on a CG-5 will work very well.

#6 letimotif

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Posted 10 April 2009 - 06:15 PM

Hey Bill,

Having used a CG5-GT for several years I can tell you it's a great mount. Noisy, but great.

I used Celestron's version of the 120mm on it and the combination was a real pleasure. Rock solid.

But, based upon what you want to load on it I think you might be disappointed at the steadiness. And that's, as you know, crucial for imaging.

If this is your first attempt at an imaging platform, and you do decide on the CG5-GT I think you will spend a lot time, and perhaps frustrating time at that, getting the equipment you mount balanced sufficiently to hold your set up steady.

There are Atlas mounts I've seen on A-Mart for around $1,000. And the CGEM looks to have some advantages over the Atlas for about $400 more.

My advice would be to wait and save up a few more bucks. I think you'd be happier in the long run. Of course, if you do go with the CG5 you can get most of what you paid for it when you sell it. So you might think of it more as a rental until you have the funds for something sturdier. Because while you might like the CGEM better in the long run . . . tempus fugit and in the long run we're all dead.

#7 waassaabee

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Posted 10 April 2009 - 06:58 PM

Bill, I'd get the best deal you can on a CG-5 now instead of waiting on a larger mount ... the experience you'll get from actual use will be very valuable.

I would also not use that 120mm scope as a guide scope ... it's simply too much dead weight that's not doing anything for you. For a nice lightweight and inexpensive autoguider get a used 50mm finder and adapt it for use with one of your DSIs (lots of threads here on CN about how to do that). That in combination with that nice 80mm APO on a CG-5 will work very well.


+1 :waytogo:

#8 EricJD

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Posted 10 April 2009 - 08:25 PM

Bill, I'd get the best deal you can on a CG-5 now instead of waiting on a larger mount ... the experience you'll get from actual use will be very valuable.

I would also not use that 120mm scope as a guide scope ... it's simply too much dead weight that's not doing anything for you. For a nice lightweight and inexpensive autoguider get a used 50mm finder and adapt it for use with one of your DSIs (lots of threads here on CN about how to do that). That in combination with that nice 80mm APO on a CG-5 will work very well.


+2 :)

#9 wsuriano

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Posted 10 April 2009 - 11:36 PM

I think I'll pick up the CG-5 but alter my guide scope strategy. I'll still plan on the CGE but put it off a year or so until after I get some experience with a GEM. So far, I've imaged on a fork mount. If I get frustrated, you'll see the CG-5 in the classifieds and I'll move to a CGE a little sooner. I doubt I'll lose much in a sale because the price is pretty good. Thanks everyone for their insights!

Bill

#10 WadeH237

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Posted 11 April 2009 - 10:17 AM

The 80mm APO is a great scope for imaging on a CG5. But I would skip the 120mm as a guider and pick up an Orion ST-80 to use as a guide scope.

-Wade

#11 bebert

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Posted 13 April 2009 - 10:56 AM

I concur with the advice given here - this is a good beginner's mount if the weight can be kept within the parameters. But keep in mind that it's noisy. Really noisy. If you're viewing from a site that's close to where others are sleeping, you might want to consider the noise.

#12 sang33ta

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Posted 13 April 2009 - 12:28 PM

The CG5-AGT is a good mount (but very noisy!)

In the UK they have the 6" Newt-AGT on sale for £450. Many people are just buying them just for the mount and flogging the Newt OTA on ebay. :D

#13 Al Canarelli

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Posted 13 April 2009 - 12:49 PM

Many are saying the CG5 ASGT is noisy...noisier than what? I have an LX200 and it's not noisier than that. I have a CGE and it's not noisier than that. I've heard a few LXDs in action and it's not noisier than them. I remember the days at many star parties when ALL goto scopes were LX200s. One could hear the hum of these telescopes from all directions and it was not so bad. I frequently use these scopes (including the CG5 ASGT) in my own backyard and have had no complaints from neighbors...not ever! So if a CG5 ASGT is very noisy, I ask, noisier than what?

#14 mclewis1

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Posted 13 April 2009 - 02:17 PM

Al,

Is your CGE really as noisy as your CG5 ... or is your CG5 really as quiet as your CGE? In general I've found the noise level of the CGE to be quite a bit lower and smoother sounding.

Yeah, the Meade LX and LXD's can be like the CG5, but the Atlas/EQ6, Sirius/EQ5, and CGEM are quite a bit quieter.

#15 bdjeep

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Posted 13 April 2009 - 03:52 PM

In my experience, the CGE is a bit quieter than the CG5.

How loud is the CG5? I measured 60 dB at 6 feet away during full slew (both RA and DEC at full speed.) That's in the range of normal conversation.

So yes, it does make some noise, and you'll have to decide if that is acceptable in your situation. I wouldn't say that is overly loud, but it is possible that the neighbors could hear it.

#16 donsinger1

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Posted 13 April 2009 - 06:26 PM

Yeah, and my CGEM is acceptable (quiter than a CG-5) on RA, but DEC is about as noisy. that does not bother me as I usually manually slew at speeds less than 9 and they are quite acceptable. The proof is in the pointing, tracking and imaging results, which are all good.

Don

#17 bebert

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Posted 14 April 2009 - 10:59 AM

I observe about 30 feet from my neighbor's bedroom. So noise is something that I'm overly conscious of...especially at 3am.

I'm not all that familiar with the noise levels of different mounts so I can't make an honest and objective comparison. But I can tell you that on cold winter nights I can hear the mount slewing from the street - almost 80 feet away. Summer nights with the insects and increased foliage aren't so bad. When the dog three houses over begins barking at my slews I consider that pretty noisy.

I've learned to plan my evening so that I get most of the slewing done before midnight. If a large slew is necessary I adjust the slew rate way down and manually slew to the general neighborhood then fine tune it with a go-to.

None of this would be a big deal if the mount didn't sound like an air raid siren. I've read where people have lined the inside of the motor housings with felt or some other type of sound absorbent material. I've not tried that.

A mount's noise level shouldn't deter one from making a purchase. It's just one thing to consider. A noisy mount is better than no mount at all.

#18 bdjeep

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Posted 14 April 2009 - 12:04 PM

I observe about 30 feet from my neighbor's bedroom. So noise is something that I'm overly conscious of...especially at 3am.


I'm in the same situation. When their windows are closed up, I don't worry about it as I can't hear it much in my own house with the windows closed. If the windows are open in the summer, then I slew with the hand controller followed by a quick go-to. Honestly though, a simple "quiet slew" option would make this mount almost perfect for the price range.






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