another barlow imaging question..

[LaVey]

Seems to be quite a hot topic with Mars being so prominent

Anyway.. another question re barlows.. I have a celestron C6s-GT (1500mm f/10) and am using the LPI webcam (eq to 6mm ep), I used a 2x barlow (one that came in the celstron ep case) but only seem to get a relativley small image (seen here: http://stargazerslounge.com/index.php/topic,20693.0.html). I am thinking of getting another barlow to increase magnification..

So.. can I get another 2x and stack them to ultimatley get 4x? Or should I buy a 4x or 5x?

Also I dont understand the whole F thing and focal length.. at F10 using my 2x I get F20?.. does my 1500mm length stay the same? does this even matter?

AND.. will this ultimately end up letting me image Mars at a closer magnification.. I know there are a lot of questions here, but you know.. noobs need answers

[LaVey]

25 views and no replies.. anyone?

I got a x3 coming so I guess its a stack it and see..

[legion48]

Yes you can stack barlows. If you have a x2 already you might be better off buying a x3, x4 or x5. Two x2 stacked will give you x4 but that's a lot off glass to dim the image. A single x4 may be a better option and you could try the x4 with your x2 for x8 when the seeing permits!

[LaVey]

cheers .. just had a look at yur mars images on your site.. 'with stacked barlows'... wicked!