Wednesday, August 11, 2010
An alternative way to mount the Astrotrac
Just found an alternative way to mount the Astrotrac on the Takahashi mini-wedge originally for the TG-SP II. This wedge is too small such that the Astrotrac might hit the tripod legs. To solve this problem, I've mounted a small quick release platform between the tripod and that mini-wedge, and the wedge was effectively raisen and thus the Astrotrac will not hit the tripod legs.
A very good side effect is that, that quick release platform enables me to rotate the wedge with respect to the tripod. That means I can fine tune the polar alignment in azimuth!
If I stay in Hong Kong, I've no need to buy another wedge or another ball head as a result of this newly found configuration. I can use this combination on the planets because the 410 head can be used for fine adjustment even with my Orion 100ED, and it is also good for the sun or the moon.
If I were to travel, my prime target will be wider field imaging, and in such case, I will only need to buy a simple ball head. And the 410 head will be reserved for polar alignment.
A side note: The Astrotrac is really light by itself. However, you need two more tripod heads (e.g. two 410) for proper operation, and thus, the weight is tripled! Therefore, it's indeed similar with a TG-SP II.
Of course, the Astrotrac has more capacity. And if you do photography along with your trip, all you need is one more tripod head plus the Astrotrac. Therefore, it's not bad afterall.
To do: I shall try out the Astrotrac + Orion 100ED on planets, moon and the sun with a Herschel Wedge, if it works, I shall definitely keep the Astrotrac and sell the TG-SP II. Otherwise, I shall conduct a few more tests.