Warning: that $200 UV filter for my telescope lens was a total scam

I bought this pricey UV filter from a camera shop in Tucson thinking it'd protect my lens, but it just added a weird blue haze to every photo I took of the Orion Nebula. Took me 3 nights to figure out the problem - now it's in the trash. Anyone else had a filter mess up their astrophotography shots?

2 comments

2 Comments

alice891mo ago

Totally feel your pain, I had almost the exact same problem with a "pro grade" UV filter I picked up for my Celestron. Put it on for a Jupiter session and the whole planet came out looking like it was underwater with this gross blue wash. Spent like two hours tweaking settings and focus before I finally just took the darn thing off and boom, crystal clear. Threw mine in the drawer and never touched it again, total waste of cash.

rubys801mo ago

The real issue here is that UV filters on telescopes are almost never needed anyway, they're designed for regular cameras to block UV light that messes with film or sensor color balance. But in astrophotography, we're dealing with wavelengths that already get filtered by our atmosphere, so adding extra glass just introduces more reflection and color cast problems. I've actually started testing filters by holding them up to a bright light before buying, you can see cheap coatings that look like a rainbow oil slick and those are the ones that kill your sharpness. What gets me is that some of these "astronomy grade" filters are just repackaged camera filters with a bigger price tag, the markup is insane (like 300% or more). Next time just skip the filter entirely and use a lens cap for storage, your wallet and your photos will thank you.

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