("Shooting to the right" : When shooting increasing the exposure as much as possible without clipping highlights, later in RAW processing decreasing the exposure as needed. Credit for that theory goes to Michael Reichmann that published this article in Luminous Landscape)
The idea here is to demonstrate an intuitive way I found to understand it by myself: Increasing the exposure one stop has an equivalent effect in terms of noise as shooting at half the ISO. Increasing two stops the exposure is like shooting at 1/4 the ISO (Always taking care of not clipping highlights and later compensating that overexposure in RAW processing)
To test it I made three shoots, one base image at ISO 400 metered with the camera that gave 1/4sec at f6.3.
Another shoot at ISO 1600 metered with the camera that gave 1/15sec f6.3 (as the sensibility increased two stops the exposure time got reduced one quarter)
AND the third one at ISO 1600 exposing to the right two stops: The metering gave 1/15sec, two stops more gives 1/4sec.
(The reason for shooting at ISO 400 and 1600 is to work with the worse noise settings so it would be more obvious in the shoots. With current cameras at low ISO settings it's difficult to perceive the noise. Notice that the technique as meaning only if you are shooting at the lower ISO setting of the camera. If you find that you can expose to the right with a higher ISO and not clipping highlights then definitely you can decrease the ISO and meter again)
1 - The base image: ISO 400 1/4sec f6.3.
Camera Canon 20D.
Raw processor Capture One LE. Noise Suppression=0 ColorNoise Suppression=0 Banding suppression=0
Sharpening Std Amount=200 Threshold=0.
Apart of the base image described above two other shots:
2 - ISO 1600 1/15 sec f6.3. Capture 1 same settings as 1
3 - ISO 1600 1/4sec f6.3. (the shoot-to-the-right) In Capture 1 Exposure compensation= -1.40 all other settings the same as in 1
These are crops at 200% magnification of the same region of the three images (it's the white rectangle in the image above)
Can you guess which is which?
© Juan Trujillo