Christmas present for myself

Athlon · Post by **Athlon** » Sat Dec 02, 2006 12:46 pm

Hi
I'm thinking of giving myself a Christmas present this year. I'm deciding between the C8-SGT and the CPC 800.

Initially i was more inclined to the C8-SGT cuz its cheaper than the CPC (and could save the money to buy a good ep). But after reading about the problem of the mount head not being able to go down to our latitude, i got a bit put off (cuz i intend to do some short-exposure astrophotography in the near future). Also, i'm not comfortable with modifying the RA housing. So can i purchase the C8-SGT without regretting? Or should i just spend a little more cash on the CPC?

Can u guys help me in my decision?
Thanks!

jermng · Post by **jermng** » Sat Dec 02, 2006 12:55 pm

Well, if the C8-SGT you're talking about is the one that comes with the CG-5 mount, it's pretty simple getting it to work at our latitudes.

The mount itself goes all the way to 0deg so the only problem is that the counterweight shafts will hit the tripod legs. There are a few common remedies:

1. Slice off the N-peg of the tripod and leave it without a N-peg or get another one soldered on between the legs if you still need fine alt-az control of the mount itself.

2. Purchase an adapter that already has the N-peg positioned between the tripod legs instead of above one leg.

3. Use a half-pier (more appropriate for long refractors

4. Make a counter-weight shaft that's short enough to clear the legs (but you might have to use more weights) You can also use a shaft that's not THAT short but use counterweights that have a smaller diameter.

If you intend to do short exposure photograhy in the near future, it might be more advisable to go for a GEM mount like the CG-5. But even then, you would want to go for a better mount in future if you get serious into astrophotography, although there have been great pictures taken with the CG-5.

river · Post by **river** » Sat Dec 02, 2006 1:37 pm

Wait a minute, I don't think you need to Slice off anything. There is two treaded hole for the N-peg on the tripod, one is above a leg and the other is between the leg. Just screw the N-peg on the hole between two tripod leg will do.

CG5 is a solid mount . You cant get any other GEM GOTO at US$699, and it works for Singapore.

if you do not want to carry counter weight and a few small part to the field and do not enjoy setup the GEM, then the CPC800 is much easier to use. You will use CPC800 more than you use C8-SGT if you are more into visual.

cataclysm · Post by **cataclysm** » Sat Dec 02, 2006 1:46 pm

IMO go for the CG-5. Its more versatile, is able to carry more load and can be broken down into smaller components for ease of transporation.

river · Post by **river** » Sat Dec 02, 2006 1:50 pm

oh yes, with C8-SGT, you can change scope (say if you get a refractor later) but you cant do that on CPC800.

Athlon · Post by **Athlon** » Sat Dec 02, 2006 2:30 pm

What's a N-peg?
How do i align the CG-5 to celestial north without the Polaris? I can't use a compass rite?

mrngbss · Post by **mrngbss** » Sat Dec 02, 2006 4:04 pm

river wrote:Wait a minute, I don't think you need to Slice off anything. There is two treaded hole for the N-peg on the tripod, one is above a leg and the other is between the leg. Just screw the N-peg on the hole between two tripod leg will do.

CG5 is a solid mount . You cant get any other GEM GOTO at US$699, and it works for Singapore.

River is right, No need to slice off anything.

Post by **weixing** » Sat Dec 02, 2006 4:11 pm

Hi,

What's a N-peg?

That's a peg on the tripod that use to do fine azimuth adjustment when doing accurate polar alignment

How do i align the CG-5 to celestial north without the Polaris? I can't use a compass rite?

For visual, just use a compass to align your mount to north and perform a 3 star alignment.

Have a nice day.

Athlon · Post by **Athlon** » Sat Dec 02, 2006 5:12 pm

weixing wrote: For visual, just use a compass to align your mount to north and perform a 3 star alignment.

How about for short-exposure astrophotography? Also, would the N-peg be crucial in this case?

Post by **weixing** » Sat Dec 02, 2006 5:42 pm

Hi,

How about for short-exposure astrophotography? Also, would the N-peg be crucial in this case?

That's depend on how short is your "short exposure" and the focal length of your scope too. By the way, you'll have more problems in Astrophotography on the CPC.

By the way, if you want to get a CG5-GT, I think there is someone who is selling his C8N-GT (8" Newtoian) ( http://www.singastro.org/viewtopic.php?t=3768 ), you may want to ask whether he is willing to just sell the mount to you... will save a lots of shipping cost if you just buy the C8 OTA. Also, I think his CG5 is on a pier, not the standard tripod.

Have a nice day.