Tal Gem-2

[Kieken]

As I was searching for new things (as every astrofreak does ;) ) I found a store in Belgium which sells the TAL GEM-2 mount for just 250€ (roughly 300$ or 400 australian dollars). I've searched the i-net but can't really find anything about this mount, so maybe you guys can help me. Does anyone know how well it works for beginning astrophotography? I'm planning on using my 4.5" newt on it to make planetary shots and if possible my first decent DSO pictures. Is it worth the money or should I look further for better but more expensive mounts (Losmandy GM8 is available for 1850€ => +-2200$ or +-3000 australian dollars)?

I've posted this also on CloudyNights (http://www.cloudynights.com/ubbthreads/showflat.php/Cat/0/Number/509126/page/0/view/collapsed/sb/5/o/all/fpart/1).

[Dennis]

Hi Kieken

It seems there is a direct relationship between the cost of a mount and three important factors for reliable, fuss-free, enjoyable DSO imaging:

• Accurate, easy, repeatable set up and polar alignment
• Smooth tracking and guiding
• Minimal amount of time tweaking, fiddling, cursing the mount

I was fortunate to start life with a Vixen GP mount which was a pleasure to use visually, excellent to use for manually guided 35mm film astrophotography and performed very well with auto-guided ccd imaging.

This well engineered and relatively expensive mount just kept meeting all the challenges I threw at it as I progressed from visual observing, through 35mm film photography to ccd imaging; the latter really tests a mount’s capabilities to its limit.

I have seen other users with cheaper Chinese clones which “look” like the Vixen GP or GPDX but when they have tried 35mm photography or ccd imaging, their mounts were simply not as capable. No doubt a lot of tweaking may help improve matters, but if you goal is reliable, pleasant and fuss-free astro-photography, then I would guess that the mount you mention is probably not adequate and it is likely to cause you a lot of frustration and disappointment.

Sorry to be the bearer of bad news!

Cheers

Dennis

[Kieken]

I'm not expecting the best from the best for 300$, but it's in promotion so maybe .... :). For the moment I'm still thinking of buying a Losmandy or Vixen mount, don't know which one and when. Must have the money first :).

[Dennis]

Hi Kieken

Various newsgroups that I frequent have sad tales of users who purchased "cheaper" mounts and they all seemed to end up being very frustrated when the mount did not perform to their expectations.

I wouldn't want to put anyone off long exposure 35mm film, DSLR astro-photography or ccd imaging, but if you want to image DSOs and achieve the kind of results that someone like Eddie Trimarchi does, then it usually requires the more up-market, established (=expensive) mounts, plus an apprenticeship in getting everything to work together (mount, camera, guiding, etc).

Even using my Vixen GP or GPDX with a 4" refractor that has a relatively short focal length of 918mm, there have been times when I just wanted to throw in the towel when you encounter one of those nights when "things just don't seem to work".

I'm not sure if I would have persisted with imaging if I had encountered the insurmountable problems of trying to make an "inadequate" mount work for me. That is not to say it cannot be done. It just comes down to how much time and tweaking you want to invest and what are acceptable results for you.

Hope that helps

Cheers

Dennis

[Kieken]

On second thought, buying the Vixen GP-DX wouldn't so bad. It's fairly cheap but used by a lot of people and with great success (looks @ "Brown Stuff" from ErwinvdVelden). Another good thing is that I can gain more experience for in a couple of years when I buy myself a high-end mount (one that can carry my 12" newton).

[Kieken]

After a month of extra research I'm back for the opinions of you guys. Some of you maybe know it already but I'll say it again for the others. I'm searching for a mount for beginning astrophotography and my budget is around 2000 euro's now. If I save enough I could get to 3.000€ but then I would need to cut down the amount of money that I spent on my girlfriend (so not an option ). I have a couple of mounts that seem ok by me but because you guys have much more experience then me I ask you to "judge" them. I'm planning on using my 4.5 newton (though I'm also looking at a couple of refractors). I'm interested in deepsky imaging.

First one: Vixen GP-DX
I've seen a couple of pictures taken with this mount and they seem pretty nice. The PE is +-15". With the Skysensor it's possible to bring it down to +-10" or so. I've read somewhere that it could carry 11kg, enough for a 4.5" newt (or something bigger?). If I buy this mount I would pay 1175 euros and then I get a tripod, dual axis motors, polar scope and a control box. At the end I would have 800 euro to spend on other things.

Second one: Losmandy G8
Losmandy is one of those names, good products for a fair price (in my eyes). It can carry around 13kg and the PE is around +-10". It would cost 1849 euros without GEMINI (with would cost 3490€). So it would be just the mount for that price. The extras are a tripod, drives and a 7kg counterweight.

Third one: Vixen Sphinx
Would cost 2000 euro, so it would not leave any room for extra's. PE is around +-10" (seen couple with +-15" ) and weightcapacity is 11kg. I haven't seen a lot of pictures with this mount so perhaps you guys could tell me.

Fourth one: Gemini G15
Just 1600 for the mount alone. It can carry an 8" newt so I think the loadcapacity is 11 or 13kg, same as the previous mounts. PE is around +-15" or better without PEC. If I would save up to 2900 I could add a Gemini Pulsar GoTo and a 12 x 30 polarfinder. The version with FS2 GoTo costs around 2700. I can't find anything on this mount, not even a simple picture taken with it. It seems that everybody owns a G41 instead of a G15. So again, I ask you guys to give your opinion on this mount.


For the moment I'm leaning towards the GP-DX because of it's low price but the G15 looks nice to.