Which star tracker ?

Hi.
I'm very very new about astrophotography.
At this time i don't have the budget to buy telescope, equatorial mount, etc. But i'm fascinated with the results achieved in the thread "You don't need a telescope", so i would like to start take photos of the sky.
I would like to buy a star tracker, which one of these you think is better?

- Vixen 35505 Polarie Star Tracker, $379 in Amazon
- iOptron 3302B SkyTracker Camera Mount, $299 in Amazon

I think there will be no problem using one of this with wide focal lenghts (APS sensor size) like 10mm, 20mm, even maybe will work with 50mm.
And maybe i would like to try bigger lenses i own like Sigma 50-150mm and Sigma 150-500mm.

I live in south hemisphere, i think both tracker should work, right?

Any advice?

Thanks !!!

If the ioptron is the one with the wedge and polar scope ( US amazon) I would save the money and go with it. Vixen makes good stuff ( I have the R200SS ) but they are a little pricey and I have heard good things about iOptron.

I vouch for the Sky Watcher Star-adventurer. I think it's a little bigger than the two you mentioned though. Maybe worth a look.

I have the iOptron it seems to work real well I did modify it with better socket head screws on the rotating plate that holds the ball head - I recently used it with my 70-200 + the 5dIII - it handled the weight fine - I had used my MK IV previously and it handled the weight buy was difficult to get it to position sometimes because the camera body is much bigger and heavier - I am real happy with it now - hope to set up this summer and get some of Andromeda

This question is asked and answered several times and if you search, there is a long thread for iOptron. But to shortly answer your good question, it all comes to mater of choice and what you expect or can afford like going for a Porsche coupe or Kia SUV.
I own and work with both so might be able to help you with that.
Few points to remember:

- Both are among the smallest (Best when mobility is the concern and you really can not move long in wilderness with a large tracker).
- Both will do the job perfectly and you simply can't go wrong with either.
- Vixen's built quality is significantly higher.
- iOptron moves twice the weight.
- Vixen has additional modes such as moon, sun and 1/2 speed tracking and you should do the homework to know why you need these features (And they can be really useful).
-iOptron comes with expensive scope, but you should pay a funny amount to get the app to know how to use the scope (That in your case, South hemisphere) I really like to see how you want to see that dim alpha centurion in first place.
Both can be roughly pointed to the either pole (Accordingly) and have good result when you use wide angle lens so don't make too much fuss about perfect polar alignment.
- Vixen has 2 AA and iOptron 4AA batteries. So guess which one will last longer, which one runs cheaper.
- Change of battery in iOptron is PAIN IN THE REAR END, Big Time... I have never had any device to have worst battery compartment than iOptron and I really hope iOptron addresses that in next version of this nice product (In every other way nice).
- iOptron has the equatorial wedge and adjustment built in, with Vixen you need a second ballhead (Functional and cheap ones on ebay are about $25) or a second small tripod head for this purpose.
- iOptron makes funny noise when at work and Vixen is almost silent.
- Vixen is about half the weight of iOptron so guess which one will cause less neck pain on a long hike to your shooting location.
- iOptron has excellent customer service and through this forum I have witnessed several astonishing nice after sale service to the owners that is one reason I may want a product in first place. I have never had any problem to call Vixen to figure out how they perform so no comment here.
- Vixen seems to be discontinued with no replacement at this level so good luck finding one ( Telescope.net has none but Amazon or B&H still have some (Not sure the customer returned items put back into new box or left overs from last supply.)

Bottom line, you will be happy with either and don't be surprise to see they can even move your heavier lenses and camera bodies than what you though. My only problem with heavier camera and lenses are inability of the tripod to hold them steadily and problems with maneuvering specially to point a long lens right up toward Zenith, rather than trackers ability to move correctly by the tracker's motor. My limit is 500mm mirror lenses or 300mm F2.8

For less money and free scope and no need to have second head for equatorial adjustment, you may want to go with iOptron. I like slick and would go with Vixen even if I am to choose again and would want iOptron address the crazy battery compartment before I ever buy from them again.

Thanks Samsen. Good comparison.

interesting thread, I really don't like star trails, but I do love star photos, so something like this might be for me. I'm curious though, it says to align it with the north star, but what if said star is behind a mountain or tree? Scope won't see through that, how do you use these things then?
ioptron looks pretty neat, good reviews online too.

Marcy wrote in post #17526952
I have the iOptron it seems to work real well I did modify it with better socket head screws on the rotating plate that holds the ball head - I recently used it with my 70-200 + the 5dIII - it handled the weight fine - I had used my MK IV previously and it handled the weight buy was difficult to get it to position sometimes because the camera body is much bigger and heavier - I am real happy with it now - hope to set up this summer and get some of Andromeda

I have the iOptron as well and the battery compartment and screws are my only complaint. Which screws did you use to upgrade it?

AbPho wrote in post #17527167
Thanks Samsen. Good comparison.

You are very welcome pal.

phantelope wrote in post #17527193
interesting thread, I really don't like star trails, but I do love star photos, so something like this might be for me. I'm curious though, it says to align it with the north star, but what if said star is behind a mountain or tree? Scope won't see through that, how do you use these things then?
ioptron looks pretty neat, good reviews online too.

Be happy if your only concern is a blocking tree or house over North star (Polaris) as our poor Southern Earth residents, despite their beautiful dark and unpolluted sky, can not see much to call Southern Pole Star. Alpha Centurion (Equivalent of Polaris for them) is too dim to act as good aiming point even when sky fully clear.
You need to know that with a wide angle lens and less than 2 minutes tracking, any rough alignment to north is a good one...
All you need to do, if you can't see northern star (Polaris) for any reason is to follow this simple instruction:

1- Make sure your surface where tripod is located is level to horizon. (Your air bubble over the tracker or tripod).
2- Knowing the correct elevation of Polaris for your city of observation (There are tones of such calculators on web, just Yahoo it), enter the correct angle on the side of tracker (iOptron gives you this scale in 5 degree markings).
3- Using a regular compass or gut feeling (If you are familiar with the location) point the setup towards the North.

Your are all set and ready to go for a tailless starry sky.

BTW if you like to take images of Wide sky at night, you will be amazed by how much a tracker could actually add to quality of your images and your only regret, not to buy it earlier!

Cheers and dark, cloudless sky to all.

great info, thanks! I'm heading up to the mountains this summer, put this thing on my wishlist. I'm sure a 2 min exposure will blow a 30 sec exposure away!

The ioptron does not have a very good periodic error curve, but if you are shooting under 180s it's fine. The. Polarie has better periodic error but is essentially the same worm gear/wheel design. The polariscope on the polarie must be passed through the center to polar align. I hear this can throw off alignment if not careful. The ioptron has a side mounted polar reticle hole which is easier to remove. If you get the polarie, buy an alt az wedge for the skywatcher star adventurer, it is very sturdy and small, much more precise than the ioptrons tiny alt az.

Other options are the astrotrac and fornax lightrac. Both are twice the price but way more accurate due to less periodic error in Right ascension. Astrotrac uses a precision screw drive to attain high accuracy tracking, while the fornax has an even more precise friction drive.

There are other choices too, Kenko sky memo, Losmandy starlapse, skywatcher star adventurer, and the ioptron star tracker, but these are way to big to be travel worthy imo. If you want something that big just get a zeq25 or a smart eq pro and benefit from dec capabilities.

phantelope wrote in post #17528624
great info, thanks! I'm heading up to the mountains this summer, put this thing on my wishlist. I'm sure a 2 min exposure will blow a 30 sec exposure away!

Have fun and if you thought, 2 min exposure will blow a 30 sec exposure away! wait and see what Nuke will do, stack of 50 or 100, 2min images, obtained in the same exact simple way with same camera after postprocessing with Free DeepSkyStacker (DSS).
Warning: These things are addictive and cause weight loss from your wallet zone!

haha, my wallet is getting used to this, just slightly moans every time I look at Adorama or B&H now

Hi, thank you all for answer, sorry for writing now.

Thanks for the information. Now i have to read and compare Vixen, iOptron and Sky-Watcher Star Adventurer.
I like Vixen modes for sun, moon, and 1/2 speed. That's a plus. Also Sky-Watcher Star Adventurer has this feature, so iOptron doesn't look attractive to me at this point.

I'm gonna research read about this two devices.

As i am on south hemisphere, how hard is to align the star tracker?


PS: sorry for my english, spanish is my natural language

The star-adventurer does come with a built in polar scope & date/time graduation circles. The graduation circles are used exclusively for polar aligning in the northern hemisphere. However, the polar scope does have marking for aligning to Octans (4 stars) in the southern hemisphere. I read it is still difficult since the stars are very faint. Using the wedge and a compass seems to be the first thing you need to use to set up the tracker. Depending on exposure times you need this might be adequate.

I can't comment on the other units polar scope.

Good luck.