Question on Focal reducers and barlows for imaging

[DanDare]

Hi,

A couple of questions.

With Mars very favourable I would like to try imaging with my F14 Mak and a webcam. What size barlow would you suggest to enable me to get a fairly decent size image? I was thinking either a 3x or 4x, but would 4x be pushing it?

With such a long focal length I have the opposite problem when it comes to imaging the moon, so is there a focal reducer available which would let me to get the whole moon in the image?

Thanks

Roy

[plasma.d00d]

Wow , similar problems / questions to me (http://stargazerslounge.com/index.php/topic,20775.0.html) , lets hope we both find an answer , I shall be watchin both threads with anticipation

[barkis]

A Teleview 2.5x Powermate would probably suit you Roy, but I think they have stopped making them. Your best chance might be the the Astro Buy and Sell Forums.

Ron.

[DanDare]

Thanks Ron, I'll keep an eye out.

I have seen a Meade 2x - 3x variable barlow on the Telescope House site, but are these OK for photgraphic use? sorry if this is a bit basic, but I'm very new to imaging.

Regards

Roy

[daz]

A decent 2x would give you f/28 which is not far short of where you want to be I would guess.

And something like the Antares 0.5 focal reducer screws straight into the nosepiece of the webcam to bring down your f ratio for the moon.

[plasma.d00d]

And something like the Antares 0.5 focal reducer screws straight into the nosepiece of the webcam to bring down your f ratio for the moon.

Daz, is there a difference in placing the focal reducer on the back of the 'scope (NexStar 8 GPS) , where the visual back goes , to placing it in the nosepiece adapter of the TouCam ?

Is one the correct way and the other not , or is it just another option ?

Cheers

plasma.d00d

[blinky]

The reducer is designed to be a certain distance from the CCD. I doubt it would work unless screwed into the nosepiece. If it is further away the reduction is increased (but so, I take it is distortion etc) and closer would reduce the reduction.

[plasma.d00d]

The reducer is designed to be a certain distance from the CCD. I doubt it would work unless screwed into the nosepiece. If it is further away the reduction is increased (but so, I take it is distortion etc) and closer would reduce the reduction.

Me is confused :? Does this one screw into the nosepiece then or back of the 'scope .... ?

Meade f/3.3 focal reducer/field flattener

The Meade f/3.3 reducer looks just like the Meade f/6.3 reducer, except it clearly is using more powerful magnification. The Meade reducer simply threads into the back of the Schmidt-Cassegrain like the Meade f/6.3 reducer.

[DanDare]

Thanks Daz, looks like its time to get the CC out again!

Cheers,

Roy

[cygnusx1]

Me is confused :? Does this one screw into the nosepiece then or back of the 'scope .... ?

Meade f/3.3 focal reducer/field flattener

Screws into back of scope (SCT thread), other end into your camera t-ring thread.

[plasma.d00d]

Screws into back of scope (SCT thread), other end into your camera t-ring thread.

Thanks