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View Full Version : Gear and Gadgets: Questions on choice of the tool for the job and the lke! Filter for Crepuscular rays


Rachel Foster
March 19th, 2011, 07:40 PM
In previous discussion of photographing crepuscular rays, someone recommended a specific filter for the lens. I may have a chance to shoot some in a fairly lovely setting this June but I can't remember what filter that was. Doing a search, I noticed Maris uses a "red filter." Any info would be greatly appreciated.

Bart_van_der_Wolf
March 20th, 2011, 07:58 AM
In previous discussion of photographing crepuscular rays, someone recommended a specific filter for the lens. I may have a chance to shoot some in a fairly lovely setting this June but I can't remember what filter that was. Doing a search, I noticed Maris uses a "red filter." Any info would be greatly appreciated.

Hi Rachel,

If a Red filter was mentioned, it must have been in combination with Black and White imaging. A Red filter absorbs Blue and thus allows to increase the recorded contrast between white clouds/fog and the blue of the sky. For color images a Polarizing filter would be used to achieve a similar effect.

However, there may be little blue background. Then it's up to postprocessing to bring out the rays that light up dust and moisture in the atmosphere. One can even Photoshop these rays in (http://www.tutorialwiz.com/rayoflight) where none are in the original scene.

Cheers,
Bart

Rachel Foster
March 20th, 2011, 11:38 AM
Thanks, Bart. I was hoping that a polarizing filter or something might help with the capture. I'll check out the link carefully.

Maris Rusis
March 20th, 2011, 04:22 PM
I don't know what it is technically about crepuscular rays but film seems to be very receptive to them. Even when the effect looks rather mild to the eye the rays always deliver provided the sky area is not overexposed.

A red filter with panchromatic film lowers the blue sky background and the rays become more prominent. For general camera work I think a ND grad filter would be more useful.

I once asked a colleague why crepuscular rays always "come out". She said "Simple, they are actually called God-Beams. Now you know."

Rachel Foster
March 20th, 2011, 05:02 PM
ND filter! That was it! Thanks!

"God beams" is lyrical and captures my fancy. Thanks, Maris.

Rachel Foster
March 20th, 2011, 05:12 PM
I've decided to buy a filter kit for both the 24-105 and 70-200. B&H carries kits for both that include a neutral density filter, UV protector, and circular polarizer.

Maris Rusis
March 21st, 2011, 05:06 PM
I've decided to buy a filter kit for both the 24-105 and 70-200. B&H carries kits for both that include a neutral density filter, UV protector, and circular polarizer.

Make sure you get a ND grad filter not just a ND filter. ND grads come in a variety of densities, typically one stop and two stop. The abruptness of the grad zone, typically called hard or soft, enables them to control sky exposure while blending (or not blending) with the shape of the horizon. Finally get a filter holder that permits sliding the filter up and down to match the horizon placement in your composition. Exact placement is best achieved while looking through the lens at the taking aperture.

Rachel Foster
March 21st, 2011, 06:00 PM
That's very helpful. Thanks!

The specs on this filter (Tiffen) say it's neutral density 0.6 and 2-stops. It doesn't specifically state grad. Based on the little reading I've done, that sounds like it's a grad filter.