View Full Version : ND Filter

2004-May-22, 01:13 PM
Hi all

Any suggestions for a 77mm filter for a Nikkor lens for use during the upcoming transit?

Additionally, the lens is a 70-200 with a 1.4TC on a digital camera with a cropping factor of 1.52 giving an effective length of 425mm. Clear skies allowing, will this give a decent image?



2004-May-22, 08:40 PM
Well, I'm no expert, but since you'll be looking at the Sun, I'd say the only sort of filter you should be using is a properly certified Solar filter:

Baader AstroSolar (http://www.astro-physics.com/index.htm?products/accessories/solar_acc/astrosolar)

Thousand Oaks Black Polymer (http://www.thousandoaksoptical.com/viewers.html)

Here's a recent thread on the subject:

Transit of Venus (http://www.badastronomy.com/phpBB/viewtopic.php?p=247184#247184)