CP or ND filter?

jucas85 · Dec 20, 2014

I just got my GoPro camera and mounted it on my bike and took it for a ride through town. I got some major sun glare in the video. I know I need a filter, but not sure if a CP or ND filter would work best. I've attached a picture from the video so you can see what the outcome was. This is also a link to the video if you want to see the whole thing. Sometimes it goes from almost completely washed out to riding in the shade and only a glare at the top. Any advice is appreciated.

https://www.youtube.com/watch?v=Op42kpVbWSU

Light Guru · Dec 20, 2014

jucas85 said:
I know I need a filter, but not sure if a CP or ND filter would work best.

Based on the picture you don't need ether of those filters. There is no filter that can solve the problems created when point a camera directly toward the sun like in your image.

Buckster · Dec 20, 2014

I don't know anything about the specifics of the GoPro cameras when it comes to settings, auto-exposure possibilities, or anything like that, but that seems like a good place to start. If you can't get any control over that, then you may need an ND, and a CP is almost always a good idea if you'll be shooting outdoors anyway, which of course the GoPros are made for.

Maybe some kind of lens hood would help, to keep the lens more in the shade most of the time, even a DIY one.

TCampbell · Dec 21, 2014

Light Guru is right. You need to provide the sunlight from shining DIRECTLY on the front of the camera lens... normally a lens hood does this job, but at very wide angles (which the GoPro uses) you end up seeing the lens hood in the shot unless the lens hood is so very shallow that it no longer provides much utility. In this case "flagging" the lens (holding something between the sun and the lens -- just out of frame) can help.

Filters usually make the situation worse because they provide nice flat "mirror" like surfaces for the strong direct sunlight to bounce around on and that just intensifies the glare. Also, polarizers don't work well on very wide-angle lenses because the amount of light blocked depends on the angle of the light as it passes through the filter and into the lens. But the problem with wide-angle lenses is that they collect light from such a broad range of angles (they are "wide angle" after all) that the tuning for one edge of the lens is very different than the optimal tuning for the OTHER end of the lens. And this causes a "banding" problem in the image. Circular Polarizers work best on 'normal' to long focal lengths ... or very mild wide angles.

TCampbell · Dec 21, 2014

lol - I love auto-mis-correct on the computer. I'm pretty sure I was typing "you need to PREVENT the sunlight from..." and it probably noticed a typo and substituted you need to "provide"... which is exactly the opposite of what I meant. Hopefully you get the idea through context though.. Sorry for the typos. :-(