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ageo
01-November-2006, 11:28 AM
Hi All,
After google bringing me here for most questions i asked it, id thought id join up and ask them direct. So here i am!

I was wondering if anyone can give me some advise on what is a good eq mount for astrophotography. I was looking at upgrading from my etx105 when i decided that instead of getting a semi good scope and mount, id get a pretty good mount and put the etx ota on it until i can afford to get a good ota.
I have seen some nice shots with an etx when piggybacked on other scopes so it should do me for a while.

The mounts im looking at are (and price range)
Meade LXD75 - AU$1,495
Skywatcher HEQ5 Pro - AU$1,799
Orion Atlas EQ-G - AU$1,699
Which one of these is better for astrophotography? Or is there other mount around the same price range that is better?
Thanks in advance.

dmill120
02-November-2006, 02:20 AM
Hi.
I don't personally have any experience with any of the Mounts you listed,
But I do Own a CG5 ASGT Mount that tracks very well with my heavy 6 inch refractor and all of my accessories.
Its got an autoguide port, but no Pec.
It can handle the 30+ lbs I have on it very well.

A Losmandy or Titan would be my choice if Money wasn't a factor.

You should look for a mount that has an Autoguide port can run on either AC with an adapter, or DC, has One of the Universal dovetail or saddle type Mount receiver, and will support not only your ETX but a much bigger and heavier load. Pec is also very desirable, (Periodic Error control).
I have heard good things about the Atlas from Orion but I'm not sure if it has an Autoguide port, and PEC as std features.
As far as the LXD75 They may come with both of these features, since they designed the Meade DSI camera with Drizzle technology to work with all of the Mounts they make, but I don't know of anyone in my club that has one.

If you plan on long exposures, an Autoguide port and PEC will make things go much easier.
keep in mind that the longer the Tube the more separation between the tube mounting rings is necessary for improved stability.
Piggy back Astrophotography was how I first started, and I can tell you from experience that differential flexure can be a problem unless you use a Saddle mount or some other rigid coupling from your main scope to your imaging scope, then you will have the problem of centering a guide star thru your main scope, and keeping the image centered in your Camera's Frame.

I did away with piggyback shooting because of this headache, and I now use a radial Offset Guider a Meade DSI One shot color and My CCD Camera all on one scope.
The radial offset guider has two 1.25 eyepiece mounts one of them has a small pick off prism that can be rotated and moved around in the field of view that my scope sees, so that finding a guide star is less of a hassle, and with this setup you don't have to have 2 cameras, you can use a illuminated reticule eye piece and just manually guide while you expose with your camera.
Dennis:)

ozark1
07-November-2006, 12:46 PM
One thing though. The etx-105 is a decent scope on a decent equatorial mount. I certainly wouldn't discount it for some astrophotography. The technique is to stack loads of CCD images together - say 100 x 16 second exposures. You'd be surprised how good the pictures are. 17th magnitude is easily accessible.

In addition unless you have a dark site, light pollution will limit even perfectly tracked long exposure work to no more than a few minutes.

Thanatos
16-November-2006, 07:57 AM
EQ mounts are bulky, but still very cost effective for AP, IMO. A well aligned scope with a decent drive can yield very nice photos - even with traditional 35mm cameras. I'm not putting down CCD's with image stacking software. They are technological marvels, but expensive. Comparable results can be obtained using more primitive hardware if you don't mind a bit of extra labor.

Kaptain K
16-November-2006, 12:19 PM
Webcams are not expensive = under $100.