I was experimenting with a variable neutral density (ND) filter today (range from ND2-ND400). The 1st/left image is with no filter. The 2nd/right image is with the filter (ND4? ND8? ... it was on the low end of the ND scale).
Observations: the filter adds some yellow hue to the sky. I don't like this. But it removes some of the 'glare' (note the difference on the plants below the 'Adults Only' sign). The color of the plants "pops" with the filter.
I don't like the effect on the sky color, but I like it a lot for the plants (and the reduced glare).
However, I didn't expect any of this. Reduced glare would be expected from a polarizing lens. Neutral density filters aren't supposed to change hue, just the amount of light that enters the lens...right?
So what should I think? Am I just plain wrong about ND filters? Is it a 'cheap' ND filter that I'm using?
@DaveMasonDotMe I think the issues comes from how Variable Neutral density filters are made which is basically two Polarlizing filters stacked and rotated at certain angles to create the different neutral density effects. Im wondering if you have an auto white balance turned on and it being affected by the polarizing effect. Perhaps set camera to daylight and try the experiment again and see if you get the color change.
@Keysalagain Ahhh. Two polarizing filters stacked. That would seem to explain the reduced glare.
I have another ND filter that's fixed at something like ND2 or ND4. It *should* be a single pane filter. I should try that one too, along with your suggestions. 👍