Posted by Karl Buiter on April 10, 2012 at 4:16 PM
I have been research this question with no clear answer on the Internet.
For the May 20 Annular Eclipse,
I have the B+W Circular ND 3.0 10-stop (also the 6 and 3 stop) in 77mm. But I have heard that NDs are not strictly adequate to cover all wavelengths for cameras - or maybe they just mean eyes?
I see Thousand Oaks Optical has a Black Polymer for the 77mm threaded size. They also have R+G but in glass and film only, not threaded.
I dont have a Lee/Cokin system - yet.
I certainly do not want to harm the sensor (using 7D and 5DmIII). And I want good color. I will not be direct viewing (especially on a telescopic) - only live view.
What would you recommend?
And to further extend, best photo tips for trying to get foreground and background on a ND-style long exposure for a solar - or are we just looking at foreground profile? Thinking maybe a two-shot.
Posted by David Bostedo on April 11, 2012 at 10:58 AM
Karl - You shouldn't hurt the sensor unless you're doing extremely long exposures and letting things blow out in the image (i.e. if you don't have severely blown highlights, not that much light has hit the sensor, therefore you can't be hurting the sensor). Even if you're letting things blow out, unless the sensor is heated to a very high temperature, there won't be any issue.
Beyond that, unfortunately, I don't have any actual shooting advice.
Posted by Mark Seaver on April 13, 2012 at 6:51 PM
Karl, if you want to check numbers, compare your ND 3.0 with the optical density, OD=ND, (or transmission) of welding goggles. My recollection from years ago, is that it was okay to look at an eclipse through welding goggles. I don't expect to find transmission (or optical density) curves for the B&W filters, but I suspect that you can find them for welding goggles and there are lots of optical filter companies that should show curves for their neutral density filters.
Discussion
2 repliesFor the May 20 Annular Eclipse,
I have the B+W Circular ND 3.0 10-stop (also the 6 and 3 stop) in 77mm. But I have heard that NDs are not strictly adequate to cover all wavelengths for cameras - or maybe they just mean eyes?
I see Thousand Oaks Optical has a Black Polymer for the 77mm threaded size. They also have R+G but in glass and film only, not threaded.
I dont have a Lee/Cokin system - yet.
I certainly do not want to harm the sensor (using 7D and 5DmIII). And I want good color. I will not be direct viewing (especially on a telescopic) - only live view.
What would you recommend?
And to further extend, best photo tips for trying to get foreground and background on a ND-style long exposure for a solar - or are we just looking at foreground profile? Thinking maybe a two-shot.
Beyond that, unfortunately, I don't have any actual shooting advice.