Field DeRotator

[OrenBoder]

Hi all,

I was just wondering if anyone could suggest a good Field DeRotator for Alt-Azimuth set-ups?

I know many people are going to suggest getting a wedge instead, but I simply don't have the time to set it up. I've researched the potential of a field derotator and kinda like the idea of it.

If anyone can suggest a good model, or knows where to get one in the UK please feel free to tell me!

[skinnyonce]

heres one in our own classifieds

[Registered users can see links. ]

[sxinias]

Field derotators get a mixed review. Never have used one personally but have read the reports of others. Some people seem to love them and other people... well, not so keen on them.

Since you use them with an azimuth mount, you still have an azimuth mount's limitations near the zenith regarding tracking and goto accuracy. While you will not need to do a polar alignment with one, you will need to synchronize the derotator to your location.

[OrenBoder]

Originally Posted by sxinias

Field derotators get a mixed review. Never have used one personally but have read the reports of others. Some people seem to love them and other people... well, not so keen on them.

Since you use them with an azimuth mount, you still have an azimuth mount's limitations near the zenith regarding tracking and goto accuracy. While you will not need to do a polar alignment with one, you will need to synchronize the derotator to your location.

Honestly, I doubt I'll ever be using it near the Zenith. I really only want it for longer exposure whilst taking photos, but nothing anywhere near comparable to the length that can be used with an EQ mount. I chose Alt-Azimuth as I dislike the EQ set-up and thought a field derotator was a good idea.

I've also seen mixed reviews which is why I cannot decide. I know that the Meade model hasn't gotten very good reviews...

Also, what do you mean by synchronising with location? - And how would one achieve this? Can it be plugged into a SynScan system to get data from that, or is that too ambitious?

[jenniferchristine]

Galactic coordinates only I'm afraid.....