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View Full Version : Do ISO and SS affect saturation at capture?



Steve Foss
08-15-2008, 05:33 PM
I'm reading contradicting information as I search about this.

I some time ago read that low ISO film and low ISO sensor settings increase saturation compared with higher ISO values. I've also heard that longer shutter speeds allow color to gather in greater concentration, also increasing saturation at capture.

Are both right? Either? Neither?

I know that some films are more contrasty and saturated than others. As in Velvia is more saturated than Sensia. That's not my question. It's really about ISO and shutter speed alone, and includes digital.

Roger Clark
08-15-2008, 07:55 PM
Digital sensors are linear, and ISO is a post sensor electronic gain so does not affect color or contrast at all. Post processing algorithms that may be specific to a given camera may do smoothing or other processing that affects color. If you shoot raw, you will have control over the post processing. In that case, if you apply the same settings with different ISO levels, the color will be the same. However, with increased ISO, noise is amplified and that may have an effect on the perceived color.

Film does have trends with ISO. In general, higher speed film has worse color, but variations between film types can be quite large.

Roger