GH5 Report of the trip in Ethiopia with the GH5

As all you are professionals and I am amateur about video, I'd like to ask one question: I use my GH5 in manual only and when I use it in my country I get wonderful videos in every time of the day, with sun and without sun. When I was in Africa I shot for some hours (around 5-6 hours) I didn't get not even one clip correctly exposed. All my clips have a brown, underexposed and with reddish dominant. When there was not the strong sun, in the evening I got good clips. My work is all to be thrown away but I'm recovering something with some make-up by putting one clip on top of the other and using the "Screening" filter on the first clip. Repeat I used my GH5 in Manual with ISO 400.

EDIT: I forgot to tell you I always used 50p, 5.6 aperture and 1/100 shutter, I always used and I turned the expensive SLR Magic ND variable filter. When I noticed everything was OK I made the shots.
 
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Did you white balance AFTER turning the variable ND filter to desired place? Don't use "preset" for sun, you must now custom white balance.

Did you turn the ND filter too far (it creates a polarized effect as you turn too far. You should be able to go to max on "10" but not beyond. Try pulling back a little too).

IR filters are helpful but I shoot outdoor in Papau New Guinea in extreme light and heat with SLR magic and GH5 and did not encounter this problem like you describe, only very mild.
 
Yup IR pollution.

Reason it looked fine in your country is because you may not have needed as much ND filtering due to a less intense sun. Different regions of the world produce different levels of infrared light as well. Just because you could shoot for years and never notice IR pollution doesn’t mean it can’t pop up under different sunlight conditions.

It’s called IR pollution for exactly that reason. It’s an abundance of infrared light that doesn’t get reduced while the visible light gets reduced with an ND filter. It’s a basic science thing we learned in grade school but the gist is that light is made out of many frequency spectrums. Most of it is visible light but it can also contain a certain level of infrared light which we can’t see but it’s there.

When we use an ND filter that filter cuts the visible light but it allows the IR light to pass through. When a camera is white balanced based on the visible light it does so without considering what the IR light is doing and it creates an ugly color shift. We can’t see Ir but the presence of the IR pollutes what the sensor sees.

Welcome to the joys of ND filtering.

Many professionals are also stumped by this phenomenon so don’t feel bad. You must have just been in a perfect scenario where the hot African sun caused a lot more IT pollution when combined with an extreme amount of variable ND filtering. It’s really hard to notice while shooting and those of us that have been burned by it eventually invested in IR ND filters to make sure it never happens again.
 
Excellent point by Filmguy....when you change or add ND, have to WB as you are changing the lighting every time you move a variable ND...but this holds true for any change in light.
 
I don't suppose there are any plugins that can rescue IR pollution in post?

Also, any IR *VARIABLE* ND filters released yet?
 
The Mark II version of the SLR Magic VND has hard stops which prevents the black X, and the locking ring allows you to adjust for polarization.

Some VNDs cut a percentage of IR light, see this cheesycam post.

You could try "chroma dark" in Resolve and see if that alleviates some of the color shift.
 
Thomas Smet said:
Yup IR pollution.

Reason it looked fine in your country is because you may not have needed as much ND filtering due to a less intense sun. Different regions of the world produce different levels of infrared light as well. Just because you could shoot for years and never notice IR pollution doesn’t mean it can’t pop up under different sunlight conditions.

It’s called IR pollution for exactly that reason. It’s an abundance of infrared light that doesn’t get reduced while the visible light gets reduced with an ND filter. It’s a basic science thing we learned in grade school but the gist is that light is made out of many frequency spectrums. Most of it is visible light but it can also contain a certain level of infrared light which we can’t see but it’s there.

When we use an ND filter that filter cuts the visible light but it allows the IR light to pass through. When a camera is white balanced based on the visible light it does so without considering what the IR light is doing and it creates an ugly color shift. We can’t see Ir but the presence of the IR pollutes what the sensor sees.

Welcome to the joys of ND filtering.

Many professionals are also stumped by this phenomenon so don’t feel bad. You must have just been in a perfect scenario where the hot African sun caused a lot more IT pollution when combined with an extreme amount of variable ND filtering. It’s really hard to notice while shooting and those of us that have been burned by it eventually invested in IR ND filters to make sure it never happens again.
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I were in this forum for 2 months and many professional guys teased me because I said: all you know your work and you are a lot expert about GH5 but you don't know my work in Africa. No professional guys told me about this problem with IR phenomenon: they always told me to study because I didn't know my GH5. It seems not even them know well all the problems I can get in Africa. I put aside the controversy and yes, you are right. I used the WB preset. Never did the manual WB. But I remember I always used my videocameras with WB preset without any problem. Unfortunately to get a better video quality this time I threw my new documentary in the trash. Today come to my home n expert guy. He uses Canon and not GH5. If verified the setting on my GH 5 and it was perfect. Even all my steps before to shoot were perfect. Someone has to tell me where I can improve to get good videos in Africa, but I hope some serious suggestions.
 
There are many here who provided you great advice, but I think some have also lost a bit of their patience.

I'm sure someone mentioned the following thought somewhere, but if not, there are many things in this business that you simply learn only from experience.

No one tells you about them and they aren't written down and you don't prepare for them; you only learn from the situation and the decisions you've made during your trial-and-error.

You're right that no one knows your work, and there is nothing left for anyone to say but only for you to do. In this particular case, you learned about IR pollution from your own experience and you can now use this lesson to improve your work, improve as a filmmaker.

You may continue to learn (examples) that one IR cut filter/strength works better for you than another, that some cameras have stronger IR cut filters than others (Canon vs. Panasonic), that you receive the most pollution between 10am-2pm but less after 4pm, that one location is worse than another location 100 miles more south, that 5200K controlled the light variation better than 6000K, that some lenses amplified the conditions more than others, etc. etc.

If you would like improvement, you have to keep learning every single day, every single trip.

Some of the smartest people here and in similar places have failed and made mistakes many times in their careers.
 
The GH5 with a good VND should be fine for IR light pollution. Your issue sounds overly extreme and is likely the failure to properly white balance. The white balance presets are close to meaningless when you add a stopped down VND filter in front of the lens, or if you over stop the VND (ie if not using Mark II). These are features of VND and ND in general, not just the GH5. You never had this problem on your other camera before because it could not do as well in lowlight. It is not as sensitive of a sensor. But more sensitivity and higher IQ means you need to block and stop more light, hence you need to know a little bit about optics and filters, too.
 
It seems if I want to get a good work I have to sell my GH5 and to buy a good videocamera. If I have to be attentive to all those suggestions that all you have recommended me, in other words when I will know better my GH5 I will be able to get a great image quality but not a good video because I will never be able to film what I see. Usually where I go people's actions flow very quickly.
 
Does anyone know a great but small video camera? I'd like to buy a videocamera with a image quality a bit better that Sony FDR-AX700. Maybe is it better to wait for next year? Is there something interesting that is going to come? Thanks
 
Adriano if you want to get a better image you will need to control that "better camera " which will have the same issues as the GH5 to get that better image. If you place the camera in auto it will likely perform just like your AX100. The improved image quality will come from your use of the camera not the camera itself. That means understanding the parameters not just setting them as someone has told you. You will have to learn to assess the situation and set the camera accordingly. If you do not want to do this then just use your AX100 and learn to use that better as the image can be improved by getting out of auto and managing the camera in full manual or in a semi auto way.
 
Ron, you are telling me the same suggestion for many times. But I'm sure I know well basic option about my GH5. In my country I got good videos. Now some people is telling me I got a problem with IR light pollution. Uffff, did you know this problem? I can't go in Etiopia twice to make the video, twice in Cameroo, twice in Chad, etc. etc. In every place there is a different light. Why with my camera I never got those problems? What should I do to solve my problem without buying another filter? Now I post a clip of my shots. It is one of the best clips: https://www.dropbox.com/s/lqazlbk8wpsnaoi/P1066605.MOV?dl=0
 
Adriano, you say you know your GH5 well but did not know about the custom preset on the dial or the ability to have the lens return to its focus when shut off so that you could quickly shoot in different conditions. Yes I am sorry I did not think about IR contamination and I guess neither did Noa. However I think you have some responsibility to find out conditions that you will shoot in yourself. The Sony AX100 has better IR filter in the lens as far as I can remember because it performed better in the theatre than the EX1 that has bad IR issues. Sorry I forgot about this I am not perfect !!! The AX100 also has auto ND so you do not need to think about what ND to use. It also has full control over WB that I guess you never used. As we said before managing the WB, shutter speed on the AX100 would have given you an improvement over what you shot before. Is it going to be as good as a GH5 well managed of course not but in auto on both I doubt whether you would see much difference and the AX100 has inbuilt ND and a long zoom with smaller sensor so focusing is easier.

That clip looks nice. Post one that is really bad and we can see if it is recoverable.
 
FoxAdriano said:
Ron, you are telling me the same suggestion for many times. But I'm sure I know well basic option about my GH5. In my country I got good videos. Now some people is telling me I got a problem with IR light pollution. Uffff, did you know this problem? I can't go in Etiopia twice to make the video, twice in Cameroo, twice in Chad, etc. etc. In every place there is a different light. Why with my camera I never got those problems? What should I do to solve my problem without buying another filter? Now I post a clip of my shots. It is one of the best clips: https://www.dropbox.com/s/lqazlbk8wpsnaoi/P1066605.MOV?dl=0
Click to expand...

2 suggestions: Stick with your video camera or hire a DP.
 
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