A quick comparison of a setup using a StarTracker versus a small EQ mount
  • LEGS -- StarTracker uses the camera tripod you already own. Tripod legs usually are included in the price of a EQ-mount.
  • Your camera tripod may be designed to be lightweight & portable, the legs under an EQ mount are not so fancy but sturdier.
  • 1st tripod head needed to adjust the StarTracker's axis to match the angle of the Earth's axis -- this adjustment is already build into the EQ mount
  • 2nd tripod head needed on top of the StarTracker to point the camera to your target -- not needed with EQ mount, it has 2 (motorized) axis built-in
  • StarTracker & EQ-mount both require polar alignment and to improve accuracy you may want to add a special polar scope and other accessories. In case of the Vixen POLARIE, this can add up. $250 for 2 ball heads, $130 for the polar scope + $60 for a tool combining a compass & bubble level. That's $440 on top of a $400 price for the POLARIE itself. Not all components are mandatory.
    The AstroTrac's base price is $580, all accessories included it adds up to $1200 (their special deal : www.astrotrac.com/Default.aspx?p=holiday-deal )
    Not all EQ mounts include an OPTIONAL polar scope, iOptron charges $60 but the GOTO mount helps if you skip the polar scope.
  • BOTH -- trackers & EQ-mounts -- need tools to level the setup and find north : a good Army compass ($25) & a carpenter's level ($5, $20 for a digital one).
  • camera/lens adapter rail -- a StarTracker usually won't need that and instead you screw the SLR body directly onto the tripod head. EQ-mount are designed to hold telescopes. The adapter I purchased cost me ~$20.
  • They all need DC power for their motors. Amount of power will vary. The tracker devices can run on as little as 2 x AA while others need 8 x AA. EQ-mounts run on 12V, which is 8 x AA. One small EQ-mount even has such a battery holder built-in.
  • EQ mount have on BIG DISADVANTAGE when it comes to size and weight. The mount weighs more and in addition it requires a counter-weight. We're not talking about Olympic-size weights. Just 6lbs for a small mount is very managable (unless go take it for a hike). Later you will see, these counterweights also are a big advantage.
  • EQ-mounts suffer another disadvantage -- BAD REPUTATION. Both do the same and face the same challenges, the odd shape & many knobs make a EQ-mount look more complicated than it is. And horror stories about efforts to align a telescope + mount give a wrong impression.

So far, you will notice, the StarTracker needs a few more bits & pieces than originally advertised. Prices will vary, especially if you shop around for these ballheads. The iOptron SkyTracker now does away with the need for two separate tripod heads by permanently attaching one to the tracker.

The setup procedure for the trackers and the EQ-mounts also isn't that much different. HOWEVER buyers of StarTrackers tend to use shorter focal lengths, these tools and accessories trade accuracy for convenience & ease of setup. If you use the same (short) focal length, you can get away with the same amount of alignent errrors. As your focal length increases, the advantages & increased accuracy of the EQ-mount become more important.
  • need to level the tripod base. Both need that.
  • find north in daylight -- compass
  • tilt upwards at an angle identical to your location's latitude. The EQ mounts have screws to accurately change that angle and secure the position. The trackers sometimes use ballheads & NO SCALE or scales with marking at 5 or 10 degree intervals. Not very accurate and I'm not sure how those settings will slip over time.
  • EQ-mount only -- adjust the counterweight to achieve balance. That doesn't take long.
  • polar align at night -- assuming both have a polar scope.
    given the small size of these tracker units, the polar scope's pupil always is VERY CLOSE to the tripod head. I found it extremely uncomfortable to bend myself into a position to look through the polar-scope. If you're wearing eye-glasses (I am), it gets worse since these polar-scopes often have very little eye-relief, meaning you have to press your eye directly onto the ocular or else it won't be in focus. Can't do that with glasses. Once you've managed to twist yourself into position and see Polaris through the polar-scope, you have to make very careful adjustments to match the stars of the Big Dipper with the pattern in the scope. Can you tilt a tiny ballhead 1/2° upwards without altering the sideways tilt while you're crouching under your tripod... ?
    Polar alignment of an EQ-mount also can be a hassle but there are some bright spots. The polar scopes sold with the mounts may be illuminated (haven't seen that with the trackers), the adjustments are made via independent screws & gears and therefore you modify one axis at a time and in small increments. The rear of the polar-scope also is in an inconvenient position but not nearly as bad as with a tracker.
    You need the same precision, regardless EQ-mount or Tracker -- focal length & observation target's position are the deciding factors : /stargazer95050/19371837.
  • EQ-mount's built-in hand-controller offers a lot more features, including POLAR-ALIGNMENT WITHOUT POLAR SCOPE. You can eliminate kneeling in a prayer position in front of the tripod and instead look through the camera's viewfinder

That last two bullet points, to me, were the ones that killed the idea of using any of these trackers. I could get a so-so alignment but as soon as I attempted to improve upon & use a polar scope, I ran ito all kinds of issues.

The first generation tracker was the ASTROTRAC and one of its limitation is, it can track for max TWO HOURS. After that the length of the screw was exceeded. Newer trackers don't have that time limit. There still are MECHANICAL limits. You want to point at the moon during winter when it is straight overhead at an 80° angle ? Chances are good, the camera body and the tracker may collide, or the tripod head cannot tilt that steep, or it can't take that load at that angle. And while the vendors claim their devices are able to handle 5...7lbs loads, I am not certain, I would entrust a $$$$ camera + lens and use it at odd angles. What -- you want to look through the view finder of the camera while it points skywards ? Good luck, given the proximity of camera, tracker & tripod top.

EQ-mounts are a different story as they move the camera + lens further away from the tripod and mount's mechanic while compensate that with counter-weights. I told you, they were useful for something. Under the same circumstance, the camera still will point upwards at 80° but at least you can crawl underneath to look at the rear LCD' (swivel screens come in handy !!) or even the viewfinder. Not comfortable but manageable. And since EQ mounts use weights to achieve a balance, they are more stable and can handle heavier lenses.

To avoid misunderstandings, there are applications these trackers are a good fit. I am arguing in favor of a EQ-mount over these trackers ESPECIALLY _IF_ you are serious about astrophotography and have plans to later add a telescope. In that case any of these tracker devices is in my opinion a waste of time and money :
  • An ASTROTRAC package "deal" currently sells for $1200 : astrotrac.com/Default.aspx?p=holiday-deal -- you can shave off a few hundred $ but the ASTROTRAC itself is $580. Adorama sell it for $740 with polar-scope, no tripod and no 2nd (ball) head
  • The VIXEN POLARIE with EXTRAS : $400 for the POLARIE + $440 for the extras and you still have to factor in the tripod. The 2nd (ball) head is included.
  • The iOptron SkyTracker represents the lowest cost solution I have seen. $450 for the tracker incl polar scope but no tripod and no 2nd (ball) head.
  • iOptron makes an GOTO EQ-mount SmartEQ Pro for $550 (polar scope & tripod included, plus some more)

If you thought buying one of these tracker devices would be the way to get started on a budget, maybe reconsider. That SmartEQ Pro wouldn't be my choice of a starter mount for someone who's planning to add a "big" telescope. But it is a good match to compare to a tracker in terms of payload. It also is a mount you can carry in a heavy duffel bag to your site -- just don't go hiking with it. And this being a GOTO mount, it has a few goodies of its own, something the StarTrackers cannot match :
  • A handcontroller to interactively slew the camera wherever you want
  • huge catalog of stars (small caveat : you have to enter GPS location & time first)
  • 11lbs payload is 50%...100% more than trackers can handle and good enough for all SLR + prime tele or fast zoom combinations short of a D4 plus a 400mm f/2.8 or 600mm f/4 (it is borderline for mid-sized telescopes)
  • runs on widely available & cheap AA batteries
  • GOTO is very convenient to starters -- enter name of the constellation and the mount slews (close) to it.
  • GOTO capabilities can greatly simplify polar alignment by using just one star or planet -- accuracy suffers but compared to the errors in a tracker's setup, this may be acceptable
  • that mount even support auto-guiding
  • TBD : not sure if a connection to a PC is possible -- ASCOM control would be a great help if you decide to add more features.

The Smart EQ Pro -- and there are similar mount from other vendors -- have a list of very useful features, they are IMO superior to the StarTracker devices and at $600 are even less expensive, this mount would not be my recommendation for a STARTER MOUNT.
The one reason I suggest a different mount is the load capacity. 11lbs isn't something to sneeze at. But as with all specs, take that with a grain of salt. For astrophotography, a general rule of thumb is, not to exceed 50% of the manufacturer's spec. This rule isn't directed against any particular vendor or mount but seems to have evolved over time from experience by many other users. 50% threshold may be a conservative estimate -- pushing the load close to the 100% surely isn't helping to improve results.

Assuming the upper end of a "mid-sized" telescope's OTA at ~15lbs (8" SCT or 120mm refractor), add 2 lbs camera, 1 lbs finder and 4 lbs guider-scope plus 3 lbs for the long Losmandy rails. That quickly adds up to 25lbs ==> my suggestion is to start with a mount that can (ideally) support 25lbs.
For most of the time you will be using this mount at 50%...75% capacity and learn with smaller scope or fewer accessories. And who knows -- maybe even at 100% it performs great ?
Once you approach that 25lbs weight limit, chances are, you want to add an even bigger OTA and that 25lbs mount will continue to be useful as you secondary or "travel" mount.

I haven't rigged the number to come up with 25lbs. I have used the approx weight of the equipment I use on what I consider the upper end of "mid-sized" (ignore the mount -- I'm talking about the stuff on top of the mount)

This 120mm refractor weighs about as much as a 8" SCT. Both good choices. You really want some autoguider once you are imaging with OTA like these. There is some more weight involved in securing the various tubes

As mentioned above -- 25lbs is the (arbitrary) threshold I have chosen. Seems other people have come to a similar conclusion. iOptron ZEQ25 is a mount that meets this requirement, and the $850 ZEQ25-package include GOTO-mount, tripod & polar scope.

Investing $850 towards a new hobby is a serious decision. The StarTrackers are a bit of a bait & switch scheme. The small size and small initial prize make it attractive and many buyers forget to sum up all the extras and compare that to an alternative.
StarTracker IMHO were successful because they are very compact and because they promoted less accurate but simplified procedures, sufficient for wide FOV and landscape shots. The smaller size & more elegant look are less intimidating than the unwieldy, very complicated looking EQ-mount
OTOH, the bulkier EQ-mount and the shape with its counter-weight surely made people feel this is a more complex tool and that surely has scared buyers off. But the alignment procedures are essentially the same.

To me there is ONLY ONE REASON I would buy a StarTracker -- if I had to carry it a long trail up a mountain to get a shot of the sky. The small size is to me the one and only selling point.
The SmartEQ or even the ZEQ25 aren't that heavy and the individual parts can be carried easily. No one would want to carry a 25lbs telescope up a hiking trail. You see, the mount is light compared to the telescopes it may carry.(ZEQ25 = 10 lbs, 6 lbs for the SmartEQ).

As you can see, EQ-mounts can offer a lot more bang for the buck in terms of features and upgrades for future setups. The GOTO controller and ability to connect to a PC and 2-axis movements to reach any location in the sky are a big distinction to the "dumb" trackers. Adding up the prices, even a far more powerful EQ-mount stands a fair chance against the StarTrackers and their slew of expensive accessories. You can learn astrophotography with a EQ mount and use your current camera + lenses to start with. And gradually upgrade to longer focal length telescope while still using the same mount for quite a while.


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