Sky-Watcher Star Adventurer 2i Photo Pack

[TrishTheDish]

Has anyone used one of these? How difficult is it to get a good enough polar alignment? Looking at wide sky photos and videos of including satellites, meteors and aircraft.

[AstroViking]

Hi Trish,

Welcome to IIS.

I think that quite a few of us have an SA2i tucked away in a cupboard somewhere. i know I do. :)

With regards to getting a good-enough polar alignment, a lot hinges on what focal length camera lens / telescope you are using.

For longer focal lengths (I'd call that anything past about 200mm) the polar alignment must be close to spot-on to avoid star trailing and/or having your target drift across the image as the night progresses. On the other hand, a 14mm lens will give good results with the SA2i pointed in the right direction.

The polar scope on the SA2i can be difficult to use and I've found that getting a good polar alignment is more a matter of luck than anything else. Unless you know the exact direction to aim, and that's really only something that comes with knowing your imaging location.

Cheers,
V.

[Max Vondel]

It's a great little mount assuming you don't get too long with that focal length. Best mounted on a HD tripod. Could be considered a 'gateway drug' to Astrophotography. Recommended without breaking the piggybank. An extra counter weight maybe needed for a heavier setup. Here's my old one mounted on an EQ6 head

[OzEclipse]

I just have the early model Sky Watcher Star Adventurer.

The attached image is a stack of 5 images each 4 minutes long taken with a 135mm lens. I stopped the lens down to f 5.6 because I was testing just how long I could track without guiding corrections. I just left the tracker to do its thing, no guiding corrections applied.

There is a bit of a lack of quality control. A friend of mine has one and he can only do 2 minute unguided exposures with a 70mm lens.

I don't use the declination axis and the long counterweight arm. I mount the camera directly on the optical axis as shown in the photo to minimise mechanical errors and flexure especially when I use the longer heavier lens. I suspect I might be able to get away with shorter exposures with an even longer lens, 1-2 mins with a 300mm lens but I have not tested this. I have a large precision equatorial mount and have no need to push things.

The polar finder is small but quite good and here in the southern hemisphere, there are two stars, mag 6.8 and 7.8 located just a few arc mins either side of the pole. The two stars can just be seen in the polar finder under a dark sky and make polar alignment a breeze. Use the brighter stars of the Trapezium to find the two fainter stars.

cheers

Joe