NDR Filter or Meter Offset

wiredhernandez · Jan 5, 2010

I am considering the purchase of 3 stop ND filter and believe it would be more effective then setting meter to underexpose. I havent used one yet so just looking for a bit of input before making the purchase. I am looking to run high AP without blown out areas of the picture so is ND BEST option? Thanks! ...

wiredhernandez · Jan 5, 2010

I meant Neutral Density Filter....

KmH · Jan 5, 2010

Graduated ND might work better.

TiCoyote · Jan 5, 2010

I've has some success using Lightroom to "paint in" the exposure on an image with a partial silhouettes or underexposure. It can make the photo a bit grainy, but it's a way to get a similar effect.

Dwig · Jan 5, 2010

wiredhernandez said:
...I am looking to run high AP without blown out areas of the picture so is ND BEST option? Thanks! ...

No, it would be a poor option. Proper exposure is the best option. Adding a filter reduces image quality.

If you simply add an ND filter the meter will correct for its density and will achieve the same relative level of exposure with the only change being the exact f/stop, shutter speed, and/or ISO. The relative densities of the various portions of the image and whether or not they clip will be totally unchanged, other than any contrast reduction that may occur from additional flare caused by the extra glass surfaces.

The only way to change how highlights render and whether they clip or not is to do one of the following:

1. reduce the exposure relative to the meter's normal reading. If using an automatic mode this means setting the EV compensation dial to a minus value.

2. sometimes you can use a graduated ND filter (GND) to reduce the brightness of a portion of the image relative to the rest. This works only for a limited range of compositions where the boundary between the excessively bright portion of the image is a reasonably straight line and that the bright portion of the image is up against one edge of the image (e.g. typical landscape image with a straight horizon).

3. if you are shooting JPEG switch to shooting RAW so you can take better advantage of the sensor's full tonal range. JPEG images are only 8-bit per pixel images and RAW files are 12 or 14 bit, depending on the camera. RAW images can record a longer tonal range than JPEG.

4. Use HDR techniques to blend multiple bracketed images into a very deep 32 or 48 bit/pixel image and then use tone mapping to reduce the image to 8 bit/pixel for printing.