More help with Saturn (not hijacking other thread)

[dave1978]

Well i got my alignment sorted last night, with a bit of practice it is quite simple really. So i turned my scope on Saturn. Im using a Meade ETX-70, i centred Saturn in the 25mm eyepiece then added a 3x Barlow lense. This gave a good sharp view but small so i tried the 9mm eyepiece still with the 3X, this made focussing very difficult.

So my question is, what lense / eyepiece combination would be best for my telescope?

3x with the 25mm, 3x with the 9mm or could i use the 9mm on its own or do i still need the 3X magnification, and would it be worth trying the 6mm eyepiece?

[geppetto]

Dave

Leaving seeing aside albeit the biggest factor in planet viewing,

the aperture of your scope is the governing factor here.

A 9mm eyepiece with a 3x barlow would be pushing way past the limits

of what your scope can do.

Just the 9mm or the 25mm and 3x barlow would give you about the same

sized views.

Difference there would be that using just the 9mm would put less glass in the chain (no barlow)

so less losses from that.

The 25 and 3x barlow on the other hand would give you better eye relief.

I would be inclined to stick with the 9mm on it's own if it's a half decent lens.

Small and sharp views are better than big and blurred

[FLO]

Hi Dave, I don't think the ETX70 is really capable of successfully imaging Saturn. It's short focal-length achromat design is best suited to low magnification wide-field views and its motors/gears are not smooth/accurate enough.

That said, you might like to try Mike Weasner's ETX site for further information:

http://www.weasner.com/etx/menu.html

[Greg]

Just my 10p's worth...

The Plossl eyepieces supplied with the ETX-70 are not great...

I'm not saying that you'll turn into a great imaging scope...You won't, as Steve says it's a widefield scope.

Beg, borrow or steal a 15mm Meade series 4000...A vast improvement for visual...

When I had the ETX-70 I never bothered with the 9mm, 15mm was the best views I had with it.

You'd be fine with some afocal moon pics.

I still say it's a nice widefield G&G Widefield scope...Should have kept it really...Would have lived in my locker at work!

Greg

[dave1978]

Thanks for the help chaps. I now have the hang of the alignment and had better viewing of Saturn just using the 9mm alone without the 3X barlow. Now im mulling over if buying the Meade LPI would be worth it.

[Greg]

dave,

Get yourself a Toucam Pro2 off e-bay.....Cheaper. That's what we all use unmoded for planetary...

[dave1978]

If i got the Toucam would i need some sort of adapter for it to fit into the eyepiece? also what software would i need for the pictures?

[Kai]

You will need a nosepiece adaptor available from most astro shops.

As for software the most popular tends to be K3ccd for the capture and Regisatx for the stacking,both available free.

[geppetto]

Agreed, a Toucam is the way to go.

This is the newest version and is easier to mod for long exposure work

should you want to further down the road.

http://www.pixmania.co.uk/uk/uk/185491/art/philips/spc-900nc-webcam.html

When getting an adaptor for this one, mention that it is this newer camera as it is

a slightly different fitting. (longer reach thread needed I think)

[dave1978]

Thanks, i have found the Registax programme but where will i find the K3ccd software? i have found a few sites but it doesnt sound like its free.

[geppetto]

It's here Dave

http://www.pk3.org/Astro/index.htm?k3ccdtools.htm

Wheel down to version 1 which is free (you need to download a key code for it also free)