WANTED: Extension Tube/old 3x plastic barlow

[iceman]

Hi all.

I'm after a 100mm or so long extension tube, or an old 1.25" 3x plastic barlow if someone has one.

I want it for more image scale with planetary imaging. Just to make keeping the planet in the FOV and off the dust motes more of a challenge :rolleyes:

I have an old 3x barlow from a $40 ebay refractor I bought 2 years ago, but it's the old 0.965" format, so it's no good.

If you have something, please PM me and let me know.

Thanks

[RAJAH235]

Mike, fwiw, why not try a 'Model' shop? (Radio Control type).They have lots of varying sizes of Alum. n plastic tubing avail. Very thin walled as well...Just a thought...:D L.
ps. Lots of other goodies too...

[[1ponders]]

How much are you prepared to pay Mike?

Ever thought of a Tele-extender. Using extended eyepiece projection with one you can achieve ridiculously long focal lengths. Using a 20mm lens I can achieve 12500mm focal lenght on a 2000mm meade SCT. If I use a 15mm lens it can go up to 17333mm FL.

If you're interested I'll have a bit of a play next weekend and see what sort of image scale I can get out of it.

[iceman]

Nah it's ok, Roger at Bintel Melbourne is sending me an old 3x plastic barlow that he's trying to get rid of.

That's the same one that DP got from Roger as well, so I know it will do the job fine.

[davidpretorius]

woo hoo, let me know if you want the holesaws to remove the central obstructions and also a couple of winds of tape on the end that goes in the powermate to make it a little more snug.

f38.5, here comes mike, doo dah, doo dah!
making big images of joop look great, all the doo dah day!!!!!!

:whistle:thanks ladies and gentlemen, i'm here till thursday!!!

[iceman]

Yes please DP, those holesaws would be great as I don't have any myself.

I'm really not looking forward to it though Dave, it's just going to make it more frustrating to keep Jupi in the centre of the FOV, off the edges and off the dust motes!

[davidpretorius]

it is 90s of concentration i can tell you! At 70 seconds, you are starting to run out of breath and the alignment corrections are more jerky.

hee hee, think of it as a challenge!!!

here is what it looks like in registax, ie not much room to spare.

Also remember to use an area of 1024 pixels otherwise there are rgb align and wavelet issues if a moon is involved.

ppmcentre also needs the cutx and cuty set at at least 440.

can't think of anything else i have had to change since the jump up in image scale. I will bring in extension tube after lunch so i can measure up holesaws. I did not use a drill, just turned the holesaws by hand ie turned the holesaw one way and the extension tube the other and every now and then, pulled the holesaw out and blew the plastic away.

It should get away tonight, please pm me your address for the 50th time.