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DJ N
06-09-2006, 12:42 PM
Hi all,

Looking at updating my scope, such that I can dabble in astro-photography. Managed to get a couple of nice shots of the moon with my 10” dob, and now I think I have been bitten by the bug.

Went to the Stockport star party the other weekend, and after chatting to a number of people, I think it best to go for an equatorial mount. Regarding budgetary constraints, I was considering either of the following….(really do want GOTO!)

· Skywatcher Pro Series HEQ5
· Celestron CG5 GO TO
· Meade LXD75


In terms of OTA, I was thinking maybe an 8” S-C.

After researching on the web, I came across the Celestron C8 SGT with CG5 goto mount. Has any one had any exposure to this set up????

Following on from this, though I will still predominantly use the setup for visual use, how accurate will polar alignment need to be such that goto would effectively place the object in view???? Or taking into account the above, would something like an LX90 be suitable??? I do like the flexibility of a GEM in that you can changeover OTAs?????

Look forward to everyone’s comments………..

Thanks,

Daniel (“Paralysis by analysis”)

ving
06-09-2006, 12:52 PM
not an expret by any standards but theres another posibility. have you considered mounting your 10" on an eq6?

DJ N
06-09-2006, 12:59 PM
I have considered the idea of mount the 10", but I think EQ6 is getting too big - had a good look at one already.

iceman
06-09-2006, 01:00 PM
What type of astrophotography do you want to primarily do? Moon/planets, or DSO's, or both?

allan gould
06-09-2006, 01:01 PM
Both the Celestrron and Meade models are based on CG5 mount and really not suitable for real(?) astrophotography due to large PE and backlash. HEQ5-Pro oe EQ6 have PEC and can be easily autoguided due to smooth PE. Both the latter come with PAS that makes easy polar algnment for visual and goto. See review in IIS.
PS at the moment I am running and autoguiding an 8" SCT with no problems on HEQ5-Pro mount
Regards, Allan

Striker
06-09-2006, 01:04 PM
Out of the 3 mounts you have chosen ...my pick would be the HEQ5 PRO.

Just be careful what your planing on doing once you start thinking about autoguiding and all the extra's needed.

DJ N
06-09-2006, 04:03 PM
I suppose in essence, a bit of everything. Probably would start with the brighter objects (short term exposure EP projection), then see where it takes me.

Cheers.

EzyStyles
07-09-2006, 01:33 AM
Hi Daniel. I thought exactly the samething as you. Get the HEQ5 mount due to lightless and less bulky. But in the end, i was glad that i got the EQ6 instead. At most the HEQ5 can sustain a 8" maybe 9.25" OTA but thats pushing it for astrophotography work. Don't forget other equipment later on which you might need also such as a guidescope. It really depends if it is going to be a permanent mount or are you planning to take it to star parties etc? I Carry my EQ6 around the backyard without any problems if you take the counter weights off. Not saying the mounts that you have listed are bad, they are great mounts, but take into consideration room for upgrades later on. Aperture fever might kick in.

Geoff45
07-09-2006, 08:48 AM
You can never have a mount that's too big.

Geoff45
07-09-2006, 08:50 AM
I agree about the CG5. I found it barely adequate for a 4" reflector, although with patience you can nurse some good photos out of it.

DJ N
07-09-2006, 10:40 AM
I thought the CG5 had a payload capacity of 35 lbs (15kg)??

Garyh
07-09-2006, 11:08 AM
hi Daniel, my choice would be the HEQ5 pro, the other mounts in my regards would be overloaded for imaging. What I have is more or less the same as the CG5 and with my new 6" reflector which weighs in about 7kgs it fails to perform. After tapping on the OTA or tripod it takes 20-30 seconds to calm down and if theres a breeze, forget it!! With that mount I would not go more than a C8 or 4-5" APO.
Mine carries a 4" APO well at a total of 7kgs with camera and guidescope.
If you can go bigger and afford it go for the EQ6 like Eric says..
Cheers Gary

DJ N
07-09-2006, 01:40 PM
Whilst on the topic of HEQ5, does anyone have any experience of the HEQ5/150mm Pro Series Maksutov package??? Or would an 8" SCT be the better option (2inches greater aperture)???

DJ N
07-09-2006, 01:43 PM
I would be predominantly viewing from metropolitan backyeard so I would be tending to go for some of the less faint objects. I realise fov is might tighter, but are the optics much "sharper"??

allan gould
07-09-2006, 02:08 PM
I've had a 5" mak and currently have 8" and 10" SCT. I compared the mak to my 5" acro refractor some time ago and they both saw about the same level of detail at the same magnification. The mak may have had the edge but it was close. I must say that the mak was syperb but heavy. No focus shift and sharp and took magnification well.
There is no comparision of 5" mak to 8" SCT. The 8" will beat it every time. Just like a 10" will beat an 8" every time.
With a metro backyard you will be combating light polution, so I would again recommend the 8"

Geoff45
07-09-2006, 02:40 PM
Actually, the tripod is the weak point. It is much steadier on a pier, but you still have problems with PE and dec backlash

EzyStyles
07-09-2006, 04:23 PM
you might find these threads quite interesting:

http://www.iceinspace.com.au/forum/showthread.php?t=11518&highlight=eq6

and

http://www.iceinspace.com.au/forum/showthread.php?t=7920&highlight=eq6

Geoff45
09-09-2006, 10:54 AM
Even the Losmandy GM 8 is only rated as 15kg and that is regarded by some as a bit optimistic, especially for astrophotography.