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bbgg
24-06-2009, 11:38 AM
I am a somewhat new to this hobby and saw Jupiter for the first time the other night using an 8 " dob. It was quite bright like an image with too much contrast so was wondering is there a good (cheap??) filter than could be used to bring out some more detail. Been having a read and so many to choose from. I could only just make out the bands. Is there also a filter that can be used for the moon? That can be blinding when looking at it!

Thanks all!

toryglen-boy
24-06-2009, 11:48 AM
different coloured filters can be bought in packs (usually 4) and can be used to great effect to bring out detail on planetary discs.

a moon filter, or neutral density filter, can be used to cut out a huge chunks of the moons brightness also. both types of filter, moon filter, and coloured filter, are really cheap, and common place in most astro shops.

:)

Starkler
24-06-2009, 01:00 PM
If thats all you could see at the time then no filter is going to help.

Personally I never use filters on the moon or planets and I could confidently say that coloured filters would top the popular list of accessories that beginners buy and then never use.

bloodhound31
24-06-2009, 10:54 PM
Ditto!:thumbsup:

Got a set here I've never used in 9 years. First thing I bought when I got my big Celestron. What a waste of money.:screwy:

Baz.

Don Pensack
25-06-2009, 02:18 AM
A #80A blue filter will reduce the brightness of the white bands and cause darker markings to pop out.
It will tint the planet blue, which most people don't like, but it will cause darker markings to become more visible.
It also works on Venus to reduce light scatter in the eye, and on the disk of Saturn to make the bands stand out.
By narrowing the wavelengths tranmitted it also helps reduce the effects of poor seeing, too.

All that said, I find my most-used color filter is a #15 yellow because it substantially tunes up contrast on the Moon and Saturn's rings.

A real fusbudget in optical image quality, however, is unlikely to be impressed by any colored filter, though. I have tried hundreds of filters, and nearly every one I've tried has reduced image quality in one way or another. So if you get a color filter, get a higher-end one like Lumicon and pass on the inexpensive Chinese ones.