Polarie Vs AstroTrac: Compare & Review

[rogerg (Roger)]

Hi all,

Now that I own both the AstroTrac and Vixen Polarie I have come up with a review and comparison of sorts. I won't claim it's flawless but I think it would be of benefit to anyone wishing to purchase such a mount.

http://rogergroom.com/astronomy-reso...vixen-polarie/

Regards,
Roger.

[Mighty_oz (Marcus)]

Nice review there Roger, good to get an informed idea from someone whose got both
Q for u - wouldn't u still need some form of tripod/stand for the wedge which adds more to the price of the Astrotrac ?

[rogerg (Roger)]

Originally Posted by Mighty_oz

Nice review there Roger, good to get an informed idea from someone whose got both
Q for u - wouldn't u still need some form of tripod/stand for the wedge which adds more to the price of the Astrotrac ?

Both the AT and Polarie need a tripod to sit on in addition to what I have mentioned in the review, so I've considered that essentially an equal added extra both would need, and only reviewed the mounts themselves

I should mention that in the review.

I usually put my AT on the Manfrotto 055XPROB and the Polarie on my Velbon GEO E540.

[naskies (Dave)]

Great article, Roger. I haven't used the Polarie yet, but the AstroTrac parts are spot on with what I've experienced.

A shame that Richard Taylor hasn't seem to have continued R&D on the AT... a few more iterations of development, and it would be really amazing.

[rogerg (Roger)]

Originally Posted by naskies

A shame that Richard Taylor hasn't seem to have continued R&D on the AT... a few more iterations of development, and it would be really amazing.

I agree completely

[gregbradley]

Nice review. I have no experience with the Astro Trac so good to read something about it.

A few additional points regarding the Polarie. You can get a cheap USB power supply off ebay for $30 or less, say a 5000MAH unit that will plug into the Polarie and you can stick it to your tripod with some Velcro. It then will run all night.

Polarie used in a horzontal orientation now becomes a panning unit for Time Lapses and is very good for that. You can also simply reverse the panning direction by flicking the switch from southern hemisphere to northern hemisphere.

The half speed tracking option is handy for a compromise between foreground and sky if you want sharper foregrounds.

I have no joy with polar scopes in the past but the Polarie unit is actually very easy to use at a dark site. You just need a dim torch to illuminate the reticle or put some tissues over your torch to dim it. I can get a very accurate polar alignment with the excellent instructions in about 5 minutes 10 minutes tops. It will then give up to 6 minutes round stars at reasonable focal length.

Additionally the Polarie has a nice optional extra which is a compass and tiltmeter that fits onto the hotshoe. I have one but haven't used it yet. It would mean you don't have to take the camera off which as you point out is a bit of an annoyance.

Just for the record you don't need an expensive ballhead. I think the one I am using cost less than $100 no need for a $545 ballhead!
A $545 ballhead defeats the purpose of a cheap but effective portable mount.
I got a carbon fibre nicely made Chinese tripod including a nice smallish ballhead (very easy to use and totally adequate) off ebay for $228. I was surprised at how well it was made. It is half the weight of my Manfrotto aluminium tripod and just as stable.

If you use a heavy DSLR and lens on Polarie you need to use a pair of pliers to tighten the tightening screws because if you don't it can slip around once the angle is sharp enough.

I also bought a cheap digital inclinometer for the Polarie to get the angle very accurate and that only takes about 1 minute or less. The little illuminated one on the side is too small to see easily in the dark to be that useful.

So keeping in mind the above the Polarie wins on more counts. The Astrotrac looks good but for my use the 2 hour limit meant it was not suitable for time lapses which are often a 5 or 6 hour period.

Greg.

[alocky (Andrew lockwood)]

Nice review Roger - now you need to get one of those Losmandy Starlapse things and compare that.
Just for accuracy's sake,
The 410 manfrotto geared head I use (and I'm the only person I've ever come across with the combination of Polarie and geared head!) 'only' cost $240. It's not even necessary as a decent three-way or ball-head is perfectly adequate, just a bit more fiddly to polar align. Greg's point on the polar scope is good, although an expensive optional extra, the Vixen one is easy to use, despite the lack of illuminated reticle and having to take the damn camera off. And forget all that mucking about with the levelling bubble, sidereal chronometer and bewildering array of dials on the back of it.
cheers,
Andrew.

[Regulus (Trevor)]

Just an addition to Greg's comments re Ball Head.
Have been using a monopod and ball head I got from eBay (Chinese) for my 600D and both are excellent. The ball head was less than $40 and is as strong and well machined as the Manfrotto and Velbon I have used over the past 25years.
Does anyone have a comparison of these items with the iOptron version?

Trevor

[rogerg (Roger)]

Thanks for your contributions everyone, there are indeed a million ways to skin a cat, and review it

Trevor - I have seen reviews of the iOptron out there but haven't seen it in person myself let alone tried it. I chose the Vixen because it seemed more proven and there was some comments about changing batteries on the iOptron, don't remember the exact criticisms.

[JB80 (Jarrod)]

It's good to se a few reviews like this because when someone I considering one of these mounts it's always a question of which one?

I can only comment on the Polarie but a couple of things spring to mind from my experience.

Firstly the battery life, now depending on brand and quality of the double A's I tend to get anywhere between 4-6 hours use out of them.
Admittedly I'm not loading the unit to it's limit weight but still for most people using a standard dslr camera and lens it's better than reported in the manual.
Also I feel the weight limit is a bit understated in the manual but then not a huge amount.

Polar alignment for me in the North is quite easy although you do need to illuminate the polar scope. The only down side is you need to remove the camera to place the Polarscope.
This has been addressed by Lacerta who have made an OAH for a EQ5 PS. I can link to that if you like.
Also rumours Vixen are looking into that too.
I find the sight hole useful too but then again I can see that it's of little use in the South.

Also I use a tripod with 3D pan head which was around $120 that the Polarie sits on and $60 ball head for use between the camera and Polarie and I haven't run into a situation yet where I need anything else.

Like you say there are many ways to go about it and I definitely understand the limitations with alignment for Southern hemisphere use.

What I would buy for it is the tiltometer as I can see that of being useful when needed.
I wouldn't get the Lacerta OAH simply because I'm already invested in the Vixen polar scope.

http://www.iceinspace.com.au/forum/s...d.php?t=106276

[mithrandir (Andrew)]

Originally Posted by alocky

Nice review Roger - now you need to get one of those Losmandy Starlapse things and compare that.
Just for accuracy's sake,
The 410 manfrotto geared head I use (and I'm the only person I've ever come across with the combination of Polarie and geared head!) 'only' cost $240.

I've got the combination StarLapse, Manfrotto 405 geared head and 475B tripod. It's a lot heavier than a Polarie setup, but it does carry my Sony a77 and Sigma 150-500 zoom. I've got a 190XPROB and while it works with any of my heads (804, 498, 229, 405) it isn't really stable enough for the StarLapse.

The one annoyance with camera tripod heads is most aren't designed for more than about +30 degrees altitude. Mine all support -90 altitude so I mount the StarLapse the wrong way round. It makes adjustment a bit awkward but that's a minor hassle.

[rogerg (Roger)]

Certainly a common thread in the replies is that cheaper heads can be used to mount the Polarie - this is definitely true and I'll augment the review with that option. I wouldn't mind one with a larger plate surface area than Manfrotto quick release plates though.

I used the geared head as it is the best direct comparison the AstroTrac wedge in terms of capabilities and rigidity. I still think this is fair as there's no doubt you can mount the Astrotrac on a less costly head also - it can be mounted just like the Polarie using a single normal bolt. Granted the AstroTrac still need more heavy duty mounting than the Polarie, but my ball heads can do it.

Originally Posted by JB80

This has been addressed by Lacerta who have made an OAH for a EQ5 PS. I can link to that if you like.

That Lacerta OAH looks good - very good idea. I am tempted to buy one or at least get my engineer neighbour to make similar for me.

[pmrid (Peter)]

Thanks for the review Roger. I too have a Polarie and no experience with the AT but have always been curious about how it works. And thanks to Greg also for those tips on using the Polarie.

Greg, I'd appreciate your further guidance on using the Polar Scope on the Polarie. I found it less intuitive than you obviously did. Is there are site you can think of that talks you through it? Is the time scale UT or local, for example? I'm getting old and dense I fear and the obvious takes a little longer to sink in these days.

Peter

Originally Posted by gregbradley

.......

I have no joy with polar scopes in the past but the Polarie unit is actually very easy to use at a dark site. You just need a dim torch to illuminate the reticle or put some tissues over your torch to dim it. I can get a very accurate polar alignment with the excellent instructions in about 5 minutes 10 minutes tops. It will then give up to 6 minutes round stars at reasonable focal length.


Greg.

[alocky (Andrew lockwood)]

Hi Peter - you don't really need to bother with any of the scales on the back. Once you've identified the Octans trapezium, just rotate the scope to match the reticle to the stars - job done. The whole time/date thing is not critical for Southern Hemisphere users as there are multiple points to determine rotation from. If all you had was Polaris - you'd need to have the reticle oriented accurately.
Cheers
Andrew.

[gregbradley]

Greg, I'd appreciate your further guidance on using the Polar Scope on the Polarie. I found it less intuitive than you obviously did. Is there are site you can think of that talks you through it? Is the time scale UT or local, for example? I'm getting old and dense I fear and the obvious takes a little longer to sink in these days.

Peter[/QUOTE]

You need a dark sky site as I am not so sure these stars are visible otherwise.

Manual is here and around page 17 describes aligning it in the southern hemisphere.
http://www.vixenoptics.com/PDF/POLARIE%20Manual.pdf


Look towards the LMC. The nearby bright star is Beta Hydrus then move away from that a little bit and you'll see 3 stars forming an arrow. They point towards the Octanes trapezium. Its a little way along from the 3 arrow stars. Now lineup the reticle pattern using a dim torch with the trapezium stars and you are all set. You will need to rotate the reticle to match the pattern of the trapezium stars before aligning them exactly.

Once you are used to this it is surprisingly easy. That first star is the only bright star near the LMC so its not hard to get started and oriented.

Greg.

[UniPol]

A shame you haven't tried out the Tak Teegul Sky Patrol II, now there's a great outfit.

[JB80 (Jarrod)]

Originally Posted by rogerg

That Lacerta OAH looks good - very good idea. I am tempted to buy one or at least get my engineer neighbour to make similar for me.

It's definitely a neat idea and will eliminate the fear of moving alignment when putting the camera on.
I'm going to wait and see what, if anything Vixen come up with.

An engineer neighbour sounds like a good neighbour to have.

[rcheshire (Rowland)]

That's a thorough review Roger. My perception of the Astrotrac is the necessity to purchase add-ons to obtain reasonable rigidity. I was put off by the upselling - add this and add that. I did have opportunity to get a close look at the AT polar scope and found that, while the eyepiece end was well made, the objective end is a plastic tube, threaded and held in place by a single grub screw. It appeared that during factory collimation the thread had been mashed and without a collar to stabilise the tube collimation was unreliable. Not consistent with what appears to be, good quality fabrication, otherwise. Richard Taylor was receptive to the feedback, however.

[rogerg (Roger)]

Originally Posted by rcheshire

That's a thorough review Roger. My perception of the Astrotrac is the necessity to purchase add-ons to obtain reasonable rigidity. I was put off by the upselling - add this and add that. I did have opportunity to get a close look at the AT polar scope and found that, while the eyepiece end was well made, the objective end is a plastic tube, threaded and held in place by a single grub screw. It appeared that during factory collimation the thread had been mashed and without a collar to stabilise the tube collimation was unreliable. Not consistent with what appears to be, good quality fabrication, otherwise. Richard Taylor was receptive to the feedback, however.

You raise a good point, there have been quality issues with the polar scopes on the AT.

[pmrid (Peter)]

Thanks for those useful and workable tips on using the polar scope.

I've ordered one of those Lacerta OAH arms for the Polarie. That was a good idea waiting to happen - like the paper-clip. Next thing will be to fit a guidescope in it!!
Peter