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CPL filters are such a nuisance

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Deleted member 94047

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I just can't seem to be able to get a consistent performance from my cpl filter; when you get the angle right - it is awesome, the colors are much more vibrant (especially on the sky and vegetation) and there is a nice contrast to the footage that is hard to get otherwise. But when you don't get it, the footage is just awful! I give you exhibits A, B, and C! First one was nice, second was ok, third is just horrible. Also, this histogram stuff is hard - how does one get it bunch up in the center? I leave my ISO at 100 and try to fiddle with the shutter speed but that doesn't seem to work much.

 
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That's the whole issue with polarisation. If you have a pair of polaroid sunglasses, try looking at your smartphone (polarised screen) with them. Turn the screen (or the glasses if you aren't wearing them.) You'll see everything from full-ish brightness view (depending on the underlying colouration of the sunglasses glass) through to complete blocking.

Sun shifts, your camera angle shifts, the best polarisation angle will shift. Pro camera polarising filters have a rotating filter angle (as do my polar-pro ones) for adjusting for the best angle. But my arms aren't long enough to reach the M2P in flight ?
 
Ninjad by Idrach ;)

Polarising filters are easy to use on a stills camera because it is in one position and you can rotate the filter to get the desired effect.
When flying your drone around you are altering the way the light interacts with the filter so it won’t always be polarising, getting the light to be going in one direction and not refracting all over the place.
Don't know if that makes any sense to you but its the best I can do.

I was going to try and explain the histogram but ended up making it more complicated than it is.
This may help you understand.
Understanding Histograms in Photography
 
Thanks Cyborg for that histogram link!

Edit: From that link - "The “correctness” of it depends on too many factors, not the last of which is your vision as well as the scene you are photographing. Histogram merely shows you the amount of tones of various brightness levels in your image, and nothing more". That certainly explains a lot. Really good,short introduction.


Thanks again!
 
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This is exactly why I ditched my set. Drone is mobile and way too easy to change angles of view as well as time of day/skyline abbreviations and went with a ND set, if you need to, then adjust colors/contrast in post. Unfortunately can't change once launched
 
This is exactly why I ditched my set. Drone is mobile and way too easy to change angles of view as well as time of day/skyline abbreviations and went with a ND set, if you need to, then adjust colors/contrast in post. Unfortunately can't change once launched
I might end up doing the same and buy a plain ND filter set.
 
This is a good reminder for people to avoid using polarizing filters until they understand how polarization works - you will probably be much happier without them unless you are willing to fly a pre-planned flight path with no direction changes.

The reason for the OP's frustration is that polarization changes with the angle to the sun, the strongest being at 90 degrees to the sun and the effect being eliminated at 0/180 degrees.

Every other day it seems I am writing a mini novel on how polarizers work haha - here are some of my replies that might help you:

M2P ND Filters...Do I need regular ND filters, if I get the corresponding ND/PL shades?

ND Filters: Polarized vs. Non-Polarized for easiest/best video quality?

Look what came today
 
So, I took the Air for a spin today and decided to give the CPL filter a last chance to prove itself. It was a bright day, full sun, no clouds in the sky and 1pm in the afternoon. I was flying around a small lake surrounded by farms. Filmed with the CPL filter on first and then a plain ND32 filter. And the CPL filter has won me over again; the contrast, and the colours are just gorgeous! See sample screen grabs below. And the ND32 proved to be to dark even for such a bright day.

Edit: first three are with the ND32, last three with the CPL filter on
 

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