poor contrast

[red dwalf]

went out other night looking at Saturn with my Skwatcher 130p, when i used the 2x barlow that came with the scope (single lens type) and a 6mm eyepiece, (taking view to 216x) i find that the focus is not very sharp and a bit blured, would it make a big differance if i was to buy a better quality barlow ? i have collimated the scope.

thanks for any help

[Merlin66]

I think at x260 even with a excellent eyepiece the view will lack contrast! That's a pretty high magnification for your size scope.

Using the 6mm with a barlow is pushing it a bit. Even if you had a ED barlow you'd still be limited. A good 4 or 5mm eyepiece is a better way to go.

[John]

I would try backing off on the magnification and using something more like 130x - 150x. 216x could well have been exceeding what the conditions on the night you were observing would allow with your scope.

With my 8 inch dob I found 170x very nice for observing Saturn and Jupiter. Also remember that the contrast of the surface features of Saturn is much lower than on Jupiter. Even my 12 inch scope only shows a couple of faint belts on Saturns disk.

John

[Doc]

I personally don't bother with barlow's anymore. You get a more detailed and contrasty view with a just an eyepiece to give you the mag you require.

[John]

If you do try slightly lower power and still cannot get a sharp image with the scope properly cooled then it is possible that the collimation is off a bit. That could also account for the lack of contrast.

John