shimmering question

[redgiantjohn]

is there anything i can do/buy that would cut down on the shimmering effect i get when i view planets at a higher magnification?im guessing its probably more to do with atmospheric or something similar its nit a major thing but if theres any tips ill gladly take them on board thanks. john

[badgers]

It's mostly atmospheric as far as I know. I've not been doing this long, but long enough to know that the detail I capture on Jupiter varies greatly depending on seeing.

I think tube currents and boundary layers over the primary affect Newtonians and are sometimes addressed with fans behind the primary, but not sure about Dobs.

[John]

The two bits of advice I would offer are:

1. Wait until an object is higher in the sky before observing, and preferably not over rooftops (although this is not always possible).

2. Ensure that your scope is fully cooled before using high powers, ie: that any warm air in the tube has had a chance to dissipate.

Constant fluctuations in seeing conditions as you observe are quite common though and is why it's worth spending time viewing an object so your eye captures those moments of excellent seeing.

Dobsonians are the same as newtonians in terms of optical design.