Oh, the eyepiece filter! So much, hope. So much, promise. So much, confusion.
When I was in high school, I bought my first set of filters. They were a planetary set and I hoped they would add much-needed color to my views of Saturn and Jupiter through the good ole Meade DS 114 Reflector. The filters arrived and to my dismay, they didn’t fit. Little did I know that my telescope used older 0.965 in. eyepieces while the planetary filters were for the now standard 1.25 in. eyepieces that come with virtually all telescopes today. What’s the point of this story, you may ask? Don’t just buy any filters! Be informed, understand their uses and above all…make sure they will fit!
What to Buy:
While the Moon may be an unavoidable pain on some nights, it can also provide great views when it is observed at the right times and with the right equipment. One filter that I’ve gotten great use out of is the Variable Polarizing Filter. This filter allows you to adjust the amount of light that enters the eyepiece from 3% to 40% of normal brightness. While the best time to view the Moon is when it is less than half full, this will help to improve contrast and detail on nights when because of the glow of the moon you have little else to view!
The main reason I had wanted those filters that didn’t fit was to give planets the color that I saw in many Hubble Space Telescope images. If this is your reasoning for buying filters, than you will be a bit disappointed. Planetary filters are not made to bring out the “natural” coloring of planets but are made to enhance various features that emit certain wave bands of light. They can also help to eliminate some of Earth’s atmospheric turbulence. Of the color filters I have the #21 orange has given me excellent views of Saturn and Mars. The Cassini Divide on Saturn looked razor-sharp and its cloud belt popped out more than usual while using this filter. On Mars, I was able to make out the polar ice cap and land features more distinctly as well.
If viewing planetary nebula is a favorite pass time of yours, than the UHC filter is exactly what you have been looking for! This filter will block out certain light waves that cause light pollution, while allowing light from emission and planetary nebulae, leaving a darkened background sky and light from certain objects that you want to see. Without it, I could not see the Owl Nebula from my moderately light polluted location. With it, this planetary nebula popped into view right where it was supposed to be.
I have continuously found Orion from Telescope.com and Zhumell and Meade from Telescopes.com to be trusted name brands with great quality and good pricing. For those looking to make the jump into filters, I would suggest these offers: