To Barlow or not to Barlow

[Bungielad]

Could someone please let me know if using an xbox webcam or a SPC900nc cam if its best to use a x2 Barlow or not when trying to image??

wheather it be lunar or planets!!

Only have a x2 at moment.

skywatcher 130p, EQ2,

[nephilim]

I'd go for it mate but only with the planets, with the moon you'll only get sections with a barlow & have to do a mosaic. Its also best to have a motor on the ra as its a nightmare to track manually while messing about with focus & capture software all at the same time.

Steve

[Bungielad]

Cheers,

I did try to catch the moon with the xbox webcam the other night with the x2 Barlow but unfortunatly even after stacking and focusing the pic was awful...just a big blob of white!!

Yes, i did only get a small section in but i thought it would have turned out better??? Hoping iv modded it correctly cuz when it was in the focal tube and running on the PC there was a bright light coming from it....i assumed it was the moon but now wondering if iv killled all the lights on the motherboared correctly??...any ideas???

[Bungielad]

Oh.....was using RA motor and PA was pretty good.

[nightfisher]

no harm in trying with barlow, the spc900 is better suited to this work

[nephilim]

Sounds like your exposure was set way too high, start with low exposure level & high gain then once youve got the planet/moon in view try & equal them out, thats how I do it with the xbox cam.

[JamesF]

What you can get away with depends on the aperture you're using, but with the SPC900 the ideal focal ratio is somewhere around f/35 to f/40. I managed that sort of focal ratio with my 127 Mak though I started from an easier place given that the native focal ratio is around f/11. If you can make it work, go for it.

You might find this helpful:

http://www.tanstaafl.co.uk/2012/03/focal-ratio-capture-length-planetary-imaging/

James