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Old 19-06-2017, 12:29 PM
mbaddah (Mo)
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Join Date: Aug 2007
Location: Sydney
Posts: 807
Quote:
Originally Posted by OzEclipse View Post
Mohammed,
Are you asking about portable trackers for eclipse chasing / photography or for astrophotography more generally?

Drive precision and PE specs for eclipse photography are pretty irrelevant. If you use 70-80mm diameter f6-f8 refractors, or a 4-5" f12.5 mak, the longest exposures are only 1-2s for such optics. Even 200" PE won't affect such a short exposure.

During a total eclipse, the primary job of the drive is to keep the image centered and by using an equatorial mount, no rotatation is required later when processing, aligning and stacking images. There are no stars to register on in the short exposures and the moon moves relative to the corona so you can't use the moon.

If you are asking the question for longer exposure astrophotography more generally, then Pete's advice holds. Also read Phil Hart's SW Star Adventurer review. The Star Adventurer has an autoguider ST4 connector which can take input from a SW Synguider.

You could also consider building a compact lightweight double arm Trott type 4 barn door.

Joe
Hey Joe,

If I'm to purchase a unit I would like it for both. The Star Adventurer definitely looks like the most promising. I used to own an Astrotrac but unfortunately sold it before deciding I was going for the solar eclipse.

I assume the star adventurer should be fine for ~400mm and tracking the sun? I wouldn't attempt astrophotography with that focal length.

I purchased http://www.amazingsky.com/eclipsebook.html and it's absolutely amazing. Well thought out with very clear and concise information. Highly recommend!

Thanks guys for all the info very helpful!
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