7D Cinestyle Test using a Pol Filter -> Bad Effects

E

etrust

Well-known member
Cam: 7d
Lens: Canon 17-55 2.8
Filter: B+W from BHPhotovideo. Price: 166USD.
Render: Vegas Pro 10. Output: MP4 720p

My first test using Technicolor cinestyle. In reality I wanted just to test only my new B+H Pol Filter. But checking the colors on the pc I have see, that Cinestyle show a strange effect from the pol filter (Curves on the sky).

I would like to discuss with you this strange effect. Using the Standard Picture Style looks better in meaning of the strange pol filter curves you can see in the sky.

You still can see the lines from the pol filter when I'm not rotating the filter using the CInestyle Picture Style. The last video was color grated and you can see better. The result it's not accetable.

Did you try your cinestyle with your pol filter?? Or what the hell I'm doing rong here :) ?

Please see in HD and Fullscreen. Thank you.

http://www.youtube.com/watch?v=ATDGq2NvK_U
 
Filter turned the camera into a GH2... :happy: no but there is something happening with the color space obviously.
 
That doesn't have anything to do with CineStyle. The sky itself isn't uniformly polarized, and you're using a pretty wide angle lens.

You would get similar results on any camera, even if you were shooting Panavision 35mm.
 
robotsound said:
That doesn't have anything to do with CineStyle. The sky itself isn't uniformly polarized, and you're using a pretty wide angle lens.

You would get similar results on any camera, even if you were shooting Panavision 35mm.
Click to expand...

Hi Robosound. I have 3 questions to you:

1) Why can we not see this bad effect using the Standard Picture Style?
2) What should be the minimum for the lens? 30mm?, 50mm?
3) I can not imagine, that it's not possible to use wide lens in combination with a pol filter without to have bad effects like this

I invite you to discuss these questions with me. Thank you :=)
 
etrust said:
I set up the project setting in vegas to 32. Same Effect.
Click to expand...

The source codec is still 8-bit and 4:2:0.

I imagine the picture styles used on the Canon DSLR's are set up to minimize issues with the codec. On the other hand, I could definitely see some traces of the effect even in the Standard profile, especially in the top left of the frame as you move your finger into the frame. I think the big thing with the second shot is the fact that exposure/sunlight is changing within the shot, and it's exaggerating the effects of the polarizer.

Also, you pushed the grade way too far IMO - killed almost any details in the shadows.
 
Very interesting. I have never used Filters and had never effects like that..

I will test the following today:

- Setup my lens not so wide like 50mm and try again.
-Sigma 30mm 1.8. Lens Size 62mm and attach a Stepup Ring 62->77mm and try again.

I'm sure there are other people with this issue. How did they solve it?
 
but guys...(and Etrust) it seems to only happen as he is turning the polorizer. Are you going to be shooting while turning the polarizer in any shot you will be using?
 
http://www.lensrentals.com/blog/2010/02/a-broad-guide-to-ultra-wide
"Because the angle of view is so wide, the angle at which sunlight enters the sensor will vary from one side of the image to the other, unless the sun is behind you. For example, if the sun is to your left, the left side of the sky will appear lighter and less blue than the right. Wide angles love overcast days and lots of clouds. Pure blue sky—not so much. A polarizing filter only polarizes light entering at certain angles, so it can actually make this phenomenon worse. Unless you absolutely need it, a polarizer is generally a bad idea on an ultra-wide lens."
 
You'll get similar but not so extreme effects (Colour banding) even if you take raw still photos with that wide a lens and a polariser.
The maximum polarisation is at 90 deg to the sun, therefore if you have a wide angle lens and look at the sky you'll see the inevitable changes in polarisation intensity.
Dave
 
jambredz said:
but guys...(and Etrust) it seems to only happen as he is turning the polorizer. Are you going to be shooting while turning the polarizer in any shot you will be using?
Click to expand...

Hi Jam :) Nono, see the last video (0:25-0:27 for sure). I'm not rotating and the effect is there!!! :=( :=( :=(
 
Last edited:
NormanBates said:
http://www.lensrentals.com/blog/2010/02/a-broad-guide-to-ultra-wide
"Because the angle of view is so wide, the angle at which sunlight enters the sensor will vary from one side of the image to the other, unless the sun is behind you. For example, if the sun is to your left, the left side of the sky will appear lighter and less blue than the right. Wide angles love overcast days and lots of clouds. Pure blue sky—not so much. A polarizing filter only polarizes light entering at certain angles, so it can actually make this phenomenon worse. Unless you absolutely need it, a polarizer is generally a bad idea on an ultra-wide lens."
Click to expand...

Thank you! Oh no I do'nt believe it.. crying :=(
 
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