• BirdForum is the net's largest birding community dedicated to wild birds and birding, and is absolutely FREE!

    Register for an account to take part in lively discussions in the forum, post your pictures in the gallery and more.

Lens Flare (veiling) + Celestron C90 (1 Viewer)

CalvinFold

Registered User
Supporter
Took my Celestron C90 out last night about 3-4 hours before sundown and managed to see my favorite two white-tailed kites. Aside from the high winds which ruined all my photos (|8.|), when I got home I notice they were all washed out.

Determined the effect is apparently a "veiling flare," a more subtle type of lens flare. Makes sense, I had to cup my hand over the finderscope on the C90 when looking around and I was pointing below or below-left of the setting sun.

So my question: are there "generic" lens hoods big enough for something like the Celestron C90? It would have to fit the outside diameter of 4.125" to 4.25" (104-108mm). Collapsable would be nice, but I doubt I have much choice.

I know I could build my own, and will if I have to, but my DIY mechanical projects have a lousy track record for the effort spent. Electronics I do, "mechanical things," not so much.

Any ideas?
 

CalvinFold

Registered User
Supporter
I may have figured this out:

Searching by "lens hood for telescope" (after realizing my "spotting scope" is really a "compact telescope") turned up a related topic for telescopes: dew shields.

A dew shield is, like a lens hood, a tube extension on the end of the (tele)scope. No fancy "rose" cutouts, but neither do all lens hoods. And it can be adjusted by simply sliding it out or back as much as needed (or to avoid vignetting).

And sure enough, there are dew shields available for the Celestron C90 (Celestron makes one, but the AstroZap comes higher regarded and a little less expensive). So going to give one of those a try. I shoot at sunrise and sunset quite a bit, so worth the investment.

(I considered making my own, but the basic components would cost almost as much in materials and time anyway. May as well buy one I know works.)
 

CalvinFold

Registered User
Supporter
Followup:

Dew Shield works pretty well for my purposes. Allows me to shoot in more flare-inducing conditions. The AstroZap is rugged, fits in my camera bag when flat, and has a nice seal around the scope while in use.

Only causes minimal vignetting as long as I'm zoomed-in.
 

Users who are viewing this thread

Top