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Hi UK1 & Shane,
is it an SCT or a newtonian you have? Reason being the longer focal length, hence a larger f/ number, would mean easier planetary viewing.
Newtonians, especially dob mounted ones, have fast focal ratios, making the images brighter for a given EP which can wash out detail in planets.
One trick used by the giant dob users when viewing the planets is to 'stop down' their scopes by placing a cardboard with a hole cut-out, with a diameter smaller than the mirror of thier scope. This increases the f/ratio and improves contrast in fast scopes. Much like closing the diaphram in a camera does.
You might like to give that trick a go. Cheap as chips a solution. Tried it on my 10" f/4.9 dob & it worked.
Another thing to keep in mind is the prevailing atmospheric conditions. Higher powers may not be viable, regardless of the scope you have. This last Saturday night, though nice for wide field viewing it was lousy for high power. Could bearly make out the two main bands on Jupiter beyond a dirty smudge. I was using my 17.5" dob, which is fast, f/4.5, but I rarely use a mask for high power, using a 5.5mm EP (363X). I'm more of a casual planetary observer. More serious observers would use one.
The month before the same issue & I was able to view through my dob & a 7" maksutov (f/12). Poor atmospheric conditions too, though not as bad.
I've only been lucky enough twice to get good seeing conditions to see good detail on Jupiter so far this year. In other postings here in IIS some folk have struggled most of the year as well for good conditions. This year seems to have been a rough one for good, stable atmospheric conditions.
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