Orion StarBlast Auto Tracker

Stumbled across this today, can tack for astrophotography, viewing, also controls Canon cameras for panoramic and time lapse photography. Seems to be a lot for a little ($199 US), still would like to read a third party review. Website LINK

It really needs a wedge for astrophotography. But good value for the other applications.

SteveInNZ wrote in post #16223047
It really needs a wedge for astrophotography. But good value for the other applications.

Does it? My reading of the manual is that this is like a dumb "Go-To" mount. It's motorized in both axes. So after you've set it up, with regards to latitude and north, it adjusts its movement rate based on where it's pointed.

Maybe I'm misunderstanding...I'm by no means an expert in these fields. But if it's not not capable of tracking for astrophotography, it's not capable of tracking for optical observing, either. And that's not what the manual says.

Can you expand on your concerns regarding the suitability of this mount?

Thanks--
Greg

If you track with an Alt-Az mount, the field appears to rotate. That's not a problem for visual observing because you're only interested in the thing in the middle and not for very long. With photography, you'll get star trails centered on the middle of the field, rather than on the celestial pole as it would if it was on a fixed mount. The amount of field rotation depends on where in the sky you are pointing.
If you put an Alt-Az mount on a wedge, the Az axis rotates around the celestial pole, making it equatorial and therefore, no more field rotation.

Thanks for that...I came across another reference to that at about the same time you were writing your response, and it was a forehead-slapper.

Of course that's why...why didn't I think of that!!!???

--Greg

SteveInNZ wrote in post #16225153
If you track with an Alt-Az mount, the field appears to rotate. If you put an Alt-Az mount on a wedge, the Az axis rotates around the celestial pole, making it equatorial and therefore, no more field rotation.

So to make this work for astrophotography a person would need to build a wedge that can be set at the local latitude. Correct?

the jimmy wrote in post #16225393
So to make this work for astrophotography a person would need to build a wedge that can be set at the local latitude. Correct?

The simple answer is yes. If you put it on a wedge the limiting factor would be your polar alignment and the time limit would be the same anywhere in the sky. If you tracked in the standard Alt-Az configuration you could do 5 seconds directly overhead or a couple of minutes towards the east or west horizon (based on a limit of 0.1 deg of rotation from Covington's book).

Given that the base has a 1/4"-20 female screw mount, can someone recomend a manufacturer's adjustable wedge that I could use between the StarBlast mount and my tripod?