GH4 Is it faulty? Low light noise at low iso

Disease8 said:
Yes but with a f1.8 lens with a speed booster (more like f1.2) and iso 400?
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Yes. If you light-starve the sensor, you get noise. Signal to noise ratio is just that -- the ratio of signal to noise. If you don't have light, you don't have a signal. And if you don't have a signal, all you have left is noise.

What you want, probably, is to capture a scene in candle light and have the shadow under the table to come out a nice clean pure black. Not going to happen. To get that image, you have to throw some light in that shadow during capture, then crush the shadow to black in post.

You don't have to believe me of course. Why would you? Thankfully, it's really easy to test. Run some tests and make your own decisions. It's not difficult, and you'll learn something.
 
If you're shooting an f1.8 on a speedbooster at iso 400 and the image is still that dark you must be in a cave! I don't know why you'd ever want to shoot anything in that kind of darkness. My problem using fast lenses with the speedbooster is that there isn't an even slower ISO setting to cut the exposure.
 
Interesting...I have never really had a problem with noise in the GH4 and I have shot in some pretty dark conditions, it always comes up really nicely.
Maybe the sensors do differ from camera to camera...I have no real problems even at 2.8 ap and pushing ISO to 1600...for even darker conditions I use a 1.7 Ap and if you use a speedbooster or a faster lens the cam should do even better.
I have only seen noise when there was virtually no light and the cam was dramatically underexposed......the histogram was all the way to the left and the light meter too.
But if underexposing in really dim light is your thing..get a Sony A7s.
 
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You be best served kicking up the ISO to whatever you have to, to get proper exposure (or ETTR), and crush in post.
 
Bern Caughey said:
We regularly shoot on four GH4 bodies & never noted any sensor performance difference.
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Yep...You wouldn't think so, its just that some say there is this "noise problem" and although I have had my GH4 for a long time now, I simply dont see this "problem"
 
First, it looks like you're shooting in CineD, so you need to grade it in post. If you don't know how to or aren't comfortable yet, try a sollution like FilmConvert. This will fix a lot of noise in darker or underexposed parts of the image. Second, you NEED to properly expose your image, even if you have to bump it up to ISO 1600.

If you're learning how to properly expose, or if you're shooting a black object like your speaker, you can fake a light meter. Turn on your zebras; 90% for 0-255 luminance and 100% for 16-235. Now get a white piece of paper. If you're exposing for soft diffused light, point the paper directly towards the lens. If you're working with a harsher light that's not directly on the front of the subject, or multiple competing lights, favor that light. Point the paper to where it is facing the dominant light and the lens diagonally. Now expose it until the zebras are barely grazing the very edge of the paper.

I think I explained that to where it could be understood. Tell me if I didn't. :)

Also, If it doesn't come out perfect after you take these steps, don't over think it. People, like us, that shoot and edit our own stuff tend to exaggerate the imperfections when most people won't notice it.
 
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Bruce Watson said:
Yes. If you light-starve the sensor, you get noise. Signal to noise ratio is just that -- the ratio of signal to noise. If you don't have light, you don't have a signal. And if you don't have a signal, all you have left is noise.

What you want, probably, is to capture a scene in candle light and have the shadow under the table to come out a nice clean pure black. Not going to happen. To get that image, you have to throw some light in that shadow during capture, then crush the shadow to black in post.

You don't have to believe me of course. Why would you? Thankfully, it's really easy to test. Run some tests and make your own decisions. It's not difficult, and you'll learn something.
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Hi no need for your patronizing tone bro. I am an experienced photographer and camera op so no need to act like I don't know anything. I appreciate your words but seriously, maybe drink less coffee? Also this IS me running some tests and I want to know if this is faulty. I will probably return it based on what Battuta said as I to think if I have a f1.2 lens I should be able to get some nice low light shots and not get loads of noise iso to 1600.
 
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Batutta said:
If you're shooting an f1.8 on a speedbooster at iso 400 and the image is still that dark you must be in a cave! I don't know why you'd ever want to shoot anything in that kind of darkness. My problem using fast lenses with the speedbooster is that there isn't an even slower ISO setting to cut the exposure.
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Yeah it wasn't even that dark! In my bedroom with a bedside lamp on in the background not like I was lighting it with only a candle. You sound sane, do you think there is a problem if you look at the three videos? Yeah I like to shoot on lower ISO as I have with the GH1, GH2 and GF1 and got clean shots. Thanks mate :)
 
doing some more tests it seems in daylight if I underexpose I do not get the noise problem. Only in low light. I love low light and natural light. This camera seems to be useless in low light.
 
Daniel Brown said:
First, it looks like you're shooting in CineD, so you need to grade it in post. If you don't know how to or aren't comfortable yet, try a sollution like FilmConvert. This will fix a lot of noise in darker or underexposed parts of the image. Second, you NEED to properly expose your image, even if you have to bump it up to ISO 1600.

If you're learning how to properly expose, or if you're shooting a black object like your speaker, you can fake a light meter. Turn on your zebras; 90% for 0-255 luminance and 100% for 16-235. Now get a white piece of paper. If you're exposing for soft diffused light, point the paper directly towards the lens. If you're working with a harsher light that's not directly on the front of the subject, or multiple competing lights, favor that light. Point the paper to where it is facing the dominant light and the lens diagonally. Now expose it until the zebras are barely grazing the very edge of the paper.

I think I explained that to where it could be understood. Tell me if I didn't. :)

Also, If it doesn't come out perfect after you take these steps, don't over think it. People, like us, that shoot and edit our own stuff tend to exaggerate the imperfections when most people won't notice it.
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I don't understand why I would do that sorry with my experience with other m4/3 cameras I can get a clean low light image underexposed if I keep the ISO really low. I know what you mean by exaggerate but honestly people will notice this amount of noise in low light conditions. Thanks for your reply.
 
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Ok in low light in my room (not too low just have the curtains closed) at ISO 200 I have noise all over the shot. I had a GF1 and could get better low light than this (yes under exposing at iso 100 in low light)! And that was not with a speedbooster and decent lens :(
https://youtu.be/YGi3Yh7cFhQ
 
Ok starting to think it is to do with that profile as some of you said. So the cine like D just brings up the shadows? Or was it because I had it on minus contrast? I used these settings because they were supposed to produce the least amount of noise? But with standard profile everything default it looks less noisey but I am loosing all my detail in any shadow.
https://youtu.be/A5OHi4qowf8
 
Disease8 said:
I don't understand why I would do that sorry with my experience with other m4/3 cameras I can get a clean low light image underexposed if I keep the ISO really low. I know what you mean by exaggerate but honestly people will notice this amount of noise in low light conditions. Thanks for your reply.
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Everyone has their own method. If your's works for you, have at it hoss.

But to make sure, I did a quick test myself. I just shot this at ISO 3200 on a GH4 with proper exposure. It was with the Sigma 18-35 and I had to stop down to '4' on my Speed Booster. Picture profile was CineD. I tried a few quick grades, and NO noise reduction. It's not pretty, but I would classify it as usable.

Ver 1
Ver 2
Ver 3

If you want the original footage straight from the camera, you can download it here.
 
Buildings.jpgTree1.jpgTree2.jpg

Yeah Here are some caps lifted directly from a fairly underexposed vid I shot a while back.
Bear in mind it was hand held, so the caps are not as sharp as they would have been if the cam was on a tripod.
But I just looked at the vid and it looks really clean and in some shots the histogram was pretty hard left and the meter was well into the minuses.
So I dont know whats going on, although the GH4 is not a low light champion, its pretty darn good...at least in my experience (plenty of it)
So maybe its down to the curves, Profile (I used Natural on these) or maybe one camera in many has a faulty sensor (I have heard of that)
Other than that...its got to be something to do with the settings somehow...cause I dont have any visible, multi colored, moving noise.
 
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