Meade f/3.3 reducer with Watec 120N+?

[Ben Ritchie]

Anyone using a Meade f/3.3 reducer with a Watec or similar? If so, what spacing are you using and how are you getting the two connected?

[Phil Fargaze]

I usually use a focal reducer with my Watec, it is the one here http://www.modernastronomy.com/camerasAstroVideo.html#AVaccessories

I mount it with the 32mm spacer, found on the same page in my link. This gives me about 0.4x reduction.

[DoctorD]

Hi Ben

I'm using the F3.3 with my SDC435 and the C8. Not sure of the exact measurement but I'll check when I'm back in the UK.

If you go over 50mm you will see bad coma in the corners.

Clear skies

Paul

[DoctorD]

Hi Ben

I use a SCT->T adapter, a number of T extensions rings and a short T-1.25 adapter then a short 1.25"->CS nose piece connected to the camera.

Ideal distance between the reducer and CCD is 57mm - I get close to this, better under than over (less reduction but also less distortion)!

I mount my IR and Moon and Skyglow filter on the nosepiece (my Moon and Skyglow is one of the old ones with IR cut) - I usually view from my garden which has a lot of light pollution, especially to the east.

All this hangs off the back of my C8 SCT.

Have a look at my gallery for some photos taken with this set-up.

http://stargazerslou...octords-photos/

Clear Skies

Paul

[Macavity]

Can't remember what the focal length of the Meade 0.3x is now... But I had the

idea they came complete with adaptors re. SCT threads or something like?

Me? I use an Antares 2" 0.5x reducer at down to about 0.3x on a Mk.I MAK150.

http://www.rotherval...ucer_d1952.html

But I'm using a add-on TS Monorail focuser to avoid the Mak's image shift...

If I don't fancy getting the bloomin' hardware out, I just stick a 0.5x ATIK - Or one of the:

http://www.opticstar...=0_10_5_0_3_510 (both around -70 to -90mm focal length, IIRC).

directly onto the Watec (long) Nosepiece. The latter 0.7x, but you can add extensions.

About 30mm from the chip for 0.5x... or 45mm(?) for 0.3x (too much mental arithmetic).

[Ben Ritchie]

Thanks folks

But I had the idea they came complete with adaptors re. SCT threads or something like?

They did, but the one I picked up didn't have them. I should be able to get it all set correctly as I have a large box of bits that can adapt, step up, step down, or extend pretty much any astronomical thread known to man (i've learned over the years to hang on to them ) but useful to know a starting point.

[Macavity]

Hi Ben,

I do remember having a Meade PDF file with this information, when I planned to buy one...

So did a Google search on "Meade Reducer PDF". At least two refs, that might help you?

http://www.iceinspac...ead.php?t=80743

http://www.cloudynig...80/Main/3047039

From the CN reference, it seems the focal length of the reducer is: ~ -90mm.

With the reducer to chip dist as: 58mm. Substituting in the "reducer formula":

R = 1 - (D / F_R) gives 0.3 = 1 - (58 / 90) - Which checks out pretty much?

So I (an unashamed nerd!) claim the reducer to chip distance is: ~58mm.

(Call it 60mm for 0.3x, 45mm for 0.5x etc. - Refocus the scope inwards...)