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Old 01-April-2008, 03:18 PM
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Dave Mitsky Dave Mitsky is offline
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Madam Captain,

I suggesting getting a narrowband nebula filter such as the DGM Optics NPB, the Lumicon UHC, or the Orion UltraBlock.

http://www.prairieastronomyclub.org/filters.htm

http://www.cloudynights.com/item.php?item_id=1578

As far as colored planetary filters are concerned, I find the Wratten #21 (orange) and 80A (light blue) to be the most useful in general.

Having a 2" long focal length, wide-field ocular to maximize your true field of view wouldn't be a bad idea either. Since your telescope has a focal ratio of f/5, and you probably don't want an exit pupil greater than 7mm, a 35mm focal length or less would be ideal. (OTOH, you could "waste" a bit of aperture for even more true field by getting a 40mm.) Most inexpensive wide-fields exhibit field edge astigmatism at f/5 so unless you want to shell out for a well-corrected eyepiece like the 35mm Tele Vue Panoptic expect to see some misshapen stars near the edge of the field.

Do you have a Barlow lens?

Dave Mitsky
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