GH4 GH4: Shutter Angle: Exposure Issues

D

dbmathis

Member
Hi All,

I have a GH4 which I intend to record 4K nature videos with. Using a lumix 14-140 lense.

I followed this guide https://suggestionofmotion.com/blog/panasonic-gh4-setup-quick-start/

Per the guide, exposure is set to manual. I also read somewhere else that it's recommended / standard to set the shutter angle at 180d (shutter speed automatically double of frame rate) to have normal looking video. This setting was the only thing I did different from the guide above.

When I set the shutter angle to 180d, f/22, ISO 200, in Texas, in the bright sun, the white balance / exposure is too bright. Set back to exposure P, and the camera adjusts to get a proper white balance. I'm assuming in P mode it just ups the shutter speed.

Looking for advice. Do I need different hardware (lenses etc)?

Best Regards

David
 
dbmathis said:
Hi All,

I have a GH4 which I intend to record 4K nature videos with. Using a lumix 14-140 lense.

I followed this guide https://suggestionofmotion.com/blog/panasonic-gh4-setup-quick-start/

Per the guide, exposure is set to manual. I also read somewhere else that it's recommended / standard to set the shutter angle at 180d (shutter speed automatically double of frame rate) to have normal looking video. This setting was the only thing I did different from the guide above.

When I set the shutter angle to 180d, f/22, ISO 200, in Texas, in the bright sun, the white balance / exposure is too bright. Set back to exposure P, and the camera adjusts to get a proper white balance. I'm assuming in P mode it just ups the shutter speed.

Looking for advice. Do I need different hardware (lenses etc)?

Best Regards

David
Click to expand...
f/22 on a micro four third sensor does not make any sense at all due to diffraction.

What you need is a neutral density filter to lower the amount of light reaching the sensor so you can open your aperture.
 
Thanks, yes, I was looking at neutral density filters last night.

I am still learning about the camera and don't understand what the camera is doing differently in auto exposure (P) to achieve proper exposure. Does the camera break the "shutter speed should be double the framerate" rule? Can I see what auto exposure is doing somewhere while in video mode?
 
dbmathis said:
Thanks, yes, I was looking at neutral density filters last night.

I am still learning about the camera and don't understand what the camera is doing differently in auto exposure (P) to achieve proper exposure. Does the camera break the "shutter speed should be double the framerate" rule? Can I see what auto exposure is doing somewhere while in video mode?
Click to expand...

Yes, if you set it to shutter priority S, shutter stays locked and everything else will change to get proper exposure. P adjusts shutter and aperture for optimal exposure. A locks aperture.
 
Just to make sure I understand. The camera breaks the shutter speed should be double the frame rate rule in video mode to achieve proper exposure, so I should switch back to manual exposure and buy a ND filter. If true, does anyone have a filter recommendation?

Also, is this a common issue people encounter or am I just overly concerned about this frame rate rule?
 
You should absolutely use Manual mode if at all possible when shooting. The 180 shutter rule gives footage the most natural looking motion blur. Faster shutter speeds can be desirable if you want that jittery, Saving Private Ryan look, or just want to extract stills from video. Variable ND filters are super convenient, as you can manually put in the ideal shutter and ISO, and then dial in the strength of the ND. Just keep in mind Variable ND filters are also polarizers, so it might change your image in undesirable ways. Some newer ones like the SLR Magic vari-nd allow you to adjust the angle to get the desired polarization. At higher ND strength, the color can shift because of infrared pollution, but the better NDs also include IR filtration. Look for filters with high quality glass (water white), avoid the plastic ones.
 
dbmathis said:
Hi All,

I have a GH4 which I intend to record 4K nature videos with. Using a lumix 14-140 lense.

When I set the shutter angle to 180d, f/22, ISO 200, in Texas, in the bright sun, the white balance / exposure is too bright.

David
Click to expand...


I think many Panasonic users shoots with f22 in sunny days because they want to follow 180 degree rule and the camera is not showing aperture in S-mode. F22 makes image soft and hazy.

Have you noticed 14-140mm OIS vibration? You should use a tripod or post stabilization.
 
Vesku said:
I think many Panasonic users shoots with f22 in sunny days because they want to follow 180 degree rule and the camera is not showing aperture in S-mode. F22 makes image soft and hazy.

Have you noticed 14-140mm OIS vibration? You should use a tripod or post stabilization.
Click to expand...

Never have noticed any vibration. I do use a tripod. Also, bought a decent ND filter since posting and have been shooting at 7.1 in the full Texas sun with a nice result.

Best Regards
 
dbmathis said:
Never have noticed any vibration. I do use a tripod. Also, bought a decent ND filter since posting and have been shooting at 7.1 in the full Texas sun with a nice result.

Best Regards
Click to expand...

OIS vibration shows in hand held stationary clips. OIS works well with tripod is not recommended.

I shooted earlier with f22 and always wondered why my videos are so soft :)

It is not nice for Panasonic to force users shoot with f22.
 
Vesku said:
OIS vibration shows in hand held stationary clips. OIS works well with tripod is not recommended.

I shooted earlier with f22 and always wondered why my videos are so soft :)

It is not nice for Panasonic to force users shoot with f22.
Click to expand...

How is Panasonic forcing users to shoot with f/22. You have polarizing filters and nd filters. I was using them to shoot film stock back in the 1970's. Using a filter properly is basic Photography 101.
 
Vesku said:
I found Panasonic S-mode funny too and started using A-mode outdoors. Some times shutter speed goes too low...
Click to expand...

I have been using manual exposure with a 180 shutter angle. The shutter angle keeps the shutter speed locked at double the frame rate and aperture visible and under manual control. From here it became obvious (after posting this thread) that f22 was overexposed and I required an ND filter.
 
Last edited:
I think very few Panasonic users shoot with a ND filter. Only some are pro users like in this forum. The others use full auto which fortunately avoids f22 but those shooting with S-mode drops to f22 and they never know why their videos are soft.
 
I recently got the SLR Vari mk2 filter because I shoot in very sunny conditions. I shot some footage the other day at f8 & f10 on 100-300mm and ETC 100-300mm. Previously I was only using 2 stops 4x4 filter and I was still climbing to about f16-18 somedays. 24p, 50fps, manual focus. I'm putting together a few minutes of it for PV, so i'll post it or link it here. Wow what a difference the vari nd has had, I really was having a hard time focusing at f16-18, and I'm more than happy with things now since I got the SLR Vari ND.
 
You must log in or register to reply here.
Back
Top