Revised Guiding Setup

[Psychobilly]

Decided I needed a longer FL guide scope whaen I'm imagign at F10 or above through the 8" SCT (FL =2032mm @ f10).

So.....

(click to enlarge)

The Skywatcher Equinoxe-66 (FL=400mm @ f6) has been replaced with the OTA of my ETX105 (FL=1500mm but at f15)

With all the various reducers & barlows etc at my disposal this should be quite a flexible setup for imaging some samller targets for a change especially as the focusser on the 66 is not well....

Billy...

Do any of the "suppliers" know if I can get a replacment focuser for the Skwatcher Equinoxe 66 and if so how much would it be?

[blinky]

At F15 are you not going to find it difficult to pick up guide stars? Not many in the FoV and they will be a lot dimmer?

[ngc2403]

the larger aperture means they will be brighter but the field of view will be much smaller, nearly 16 times smaller area of the sky with the stars being roughly 2.5 times brighter.

if by the looks of things the guide scope can't be moved in the rings, then it could cause problems finding suitable guide stars

ally

[Psychobilly]

We will have to wait and see.....

I only have a few targets in mind that i want to image at long FL on the 8" so needed the extra FL in the guidescope to get as tight a guiding as possible...

I can easily drop the ETX to 750mm at f7.5

Now if only the clouds would disappear then i might get to try it...

I also had no probs with guide stars from the "66" at f12 always gettign a star (without moving the scope in the rings) at 2s exposure usually had one with 1s exposure with the DSI as the guidecam...

Again...only time and clear skies will tell...

[Psychobilly]

Ok finally got some clearish skies for the first test...

No probs finding guide stars for M57 at 1s exposure on the DSI IIC good few to choose from at 2s so far so good....

just doing some 5 min test shots

Might want to tweak the PHDGuide settings as I have gone from 400mm to 1500mm FL ont he guidescope...

Will see how things go...

Billy...

[philj]

Nice one Billy you should get nice tight stars with that.

Ive been guiding with a Mak 127 for years using a Mintron.

Folk said that I would struggle at F12 to get guide stars but I have had no problems at all, even with the Mintron set at 1/4 integration of what its capable of.

Phil

[Psychobilly]

If its not clouds its contrails...

Contrail city out there at teh moment and not dissapearing to quickly either...

I have just added the T mount x2 teleconvertor between the 8" and the 350D for a spot of F20 (4064mm) imaging... if the trails disperse...

Billy...

[Psychobilly]

Only a single frame M83 ISO1600 CPC800 @ f20 guided using ETX105 at f15 with DSI IIC 1s exposure PHDGuide..

(click to enlarge)

Loads of noise Rubbish framing and a hair in there somewhere...

But nice tight stars with the CPC at F20 (FL = 4064mm)