GH4 exposure/noise problem

[JazzBox]

Dear all,

some days ago I shot a little promo for a friend with my GH4, a practical light and a mini-LED to have a sort of "chiaroscuro" on his face.

I shot with "natural" (with contrast -3 and saturation -5), 25 fps, 1/50, 500 ISO, 3400° K and 1080 - 100mbps. The lens was a CY Zeiss 35mm f/2.8 (at 2.8).

I exposed with the blacks "kissing" on the left but not crushed out.

I see some bad "grain" on the curtain (I noticed it before in other videos I shot, but just when underxposing seriously) and a lot of moire on the guitar' strings near the soundhole. 

I'm going to buy a G7 as soon as possible, but in the meantime I'd like to shoot as underexposed and low-key as much as I can: I'd like to have a look similar to Andy Lee's Pandora, with great chiaroscuro but not grain in the middle. 

It's the first time in 2 years I have this bad grain at so low ISO in the middle. Also the moire never was so severe: maybe I used not enough light (and not the same lights I always use), maybe my GH4 is faulty... I don't know.

I post the test here: the first 20 seconds are the clip straight from the camera, the second 20 are the same clip with a little color test for a "vintage" look:

the password is "gh4"

Thank you in advance for your kind advices!

 

[funkyou86]

Your GH4 is not faulty. I'm having the same issue with mine. Just shot a video at night, and it's full of noise, I was shooting with ISO 400. IMO it's the downside of the MFT sensor, but I noticed that grading helps to smooth this noise out.

Here are some snapshots from my footages (straight from the camera).  The second one was shot in 4K, the first and last one in 1080p 200mBit/s

[bunk]

2 hours ago, JazzBox said:

I shot with "natural" (with contrast -3 and saturation -5),
 

I think there lies your problem. I keep saturation to 0 or even plus 2 when shooting in the dark. It doesn't prevent the 'grain' but it keeps "grain clouds" to a minimum. Not a huge difference, but visible.

Apart from that I think your choice of lights (green red) might have amplified it and explain why it didn't happen at other occasions.

...for what it's worth.

[JazzBox]

3 hours ago, funkyou86 said:

Your GH4 is not faulty. I'm having the same issue with mine. Just shot a video at night, and it's full of noise, I was shooting with ISO 400. IMO it's the downside of the MFT sensor, but I noticed that grading helps to smooth this noise out.

Here are some snapshots from my footages (straight from the camera).  The second one was shot in 4K, the first and last one in 1080p 200mBit/s

Thank you!

2 hours ago, bunk said:

I think there lies your problem. I keep saturation to 0 or even plus 2 when shooting in the dark. It doesn't prevent the 'grain' but it keeps "grain clouds" to a minimum. Not a huge difference, but visible.

Apart from that I think your choice of lights (green red) might have amplified it and explain why it didn't happen at other occasions.

...for what it's worth.

Thank you!
Yes, the lights was just what we have in that room plus a mini-Led... normally I tend to shoot with far more light... Luckily that was not a paid gig, but just a favor for a friend... but I think I have to buy the G7, that (Andy Lee says and I'm sure of that seeing the results) it is far better in low light. 

[funkyou86]

1 hour ago, JazzBox said:

Thank you!

Thank you!
Yes, the lights was just what we have in that room plus a mini-Led... normally I tend to shoot with far more light... Luckily that was not a paid gig, but just a favor for a friend... but I think I have to buy the G7, that (Andy Lee says and I'm sure of that seeing the results) it is far better in low light. 

You're welcome  Is there a point to get the G7 when the GH5 will be announced in mid september? 

Anyway, try to turn the grain and the noise to your advantage, make it look like it was a part of the post process  I shot this with (James Miller like) Cinelike D, but after half of year shooting with the GH4 and these settings, I'm going to switch to Cinelike V. The reason is pretty straight forward, there is no point shooting "pseudoflat", your DR is not better, you're getting far more noise and you have to grade heavily. Of course there are scenarios where you have to blacks from crushing, but otherwise, shooting to near rec709 seems like a better option with the GH4. I need to get these LUTS and after that we'll see If I regret it :D

I really hope that the GH5 will have a rec709 preview with the V-log.

[M Carter]

6 hours ago, JazzBox said:

... but I think I have to buy the G7, that (Andy Lee says and I'm sure of that seeing the results) it is far better in low light. 

There's always going to be something more to buy. I don't know that you "have to" buy a new system to get the look you want. I'd use more light, but in the same proportions, get the iso down. With 8-bit footage, I try to fill in the blacks a bit more, just a big source of fill to bring everything up a half stop or so. Sort of like "lighting flat" vs. a flat profile, and then push up the blacks in post. I never mess with faux-log or anything-log with 8-bit though, just seems to noise everything up in the long run.

By the way, on my screen at the posted resolution, there was no noise that really jumped out at me. Full screen there's a lot of noise in the mids, which is odd. But nothing neat video wouldn't work well on.

[PannySVHS]

1 hour ago, M Carter said:

There's always going to be something more to buy. I don't know that you "have to" buy a new system to get the look you want. I'd use more light, but in the same proportions, get the iso down. With 8-bit footage, I try to fill in the blacks a bit more, just a big source of fill to bring everything up a half stop or so. Sort of like "lighting flat" vs. a flat profile, and then push up the blacks in post. I never mess with faux-log or anything-log with 8-bit though, just seems to noise everything up in the long run.

By the way, on my screen at the posted resolution, there was no noise that really jumped out at me. Full screen there's a lot of noise in the mids, which is odd. But nothing neat video wouldn't work well on.

Exellent statement. I think it is a pity that lighting sometimes is one of the most scaring aspects. It´s not scary at all though, it´s just scaring the heck out of us ambitious video lovers some times for no good reason. But it really is not such a big deal, if one has the chance to rent for little money or even buy or DIY.

Or utilizing natural light. It is really worth it for the fun of creating or sculpting an image with light, enjoying the process of creating and the possiblities of images and expressions.

[andy lee]

the G7 is significantly better in low light than the GH4 it has a newer cleaner better sensor , you dont get those issues with the G7 , its very clean in low light blacks . its is noticably better .

[JazzBox]

2 hours ago, M Carter said:

There's always going to be something more to buy. I don't know that you "have to" buy a new system to get the look you want. I'd use more light, but in the same proportions, get the iso down. With 8-bit footage, I try to fill in the blacks a bit more, just a big source of fill to bring everything up a half stop or so. Sort of like "lighting flat" vs. a flat profile, and then push up the blacks in post. I never mess with faux-log or anything-log with 8-bit though, just seems to noise everything up in the long run.

By the way, on my screen at the posted resolution, there was no noise that really jumped out at me. Full screen there's a lot of noise in the mids, which is odd. But nothing neat video wouldn't work well on.

You're right!
When I have time to set up the camera I prefer the ProRes 10 bit from the BlackMagic Micro Cinema, I love the BlackMagic codec, but normally for quick gig I use the GH4 that is far more easy for my taste: changing WB, ISO, Shutter Speed etc.. it's super fast, while on the BM it's quite slow.

With GH4 I started with Cine-D, but after some times I went for the Natural profile. I'd like to buy the G7 in order to have a nice little camera that could become the B camera when GH5 will arrive. 

Probably I never noticed that noise because normally I use a lots of light. I'll put more attention to lights next time!

58 minutes ago, andy lee said:

the G7 is significantly better in low light than the GH4 it has a newer cleaner better sensor , you dont get those issues with the G7 , its very clean in low light blacks . its is noticably better .

I tried it and I loved it! A friend of mine has it and it is a great camera, even in 1080p!

[andy lee]

ps I always keep the g7 at 800 iso or under , I shot 80% of the Pandora movie at 800 iso and I went down to 640 for the rest of it , this film is mainly all shot at night there are no day scenes in the movie at all , so the G7 let me shoot in the low light 3 or 4 stops under exposed that I like to work at to get the look I use.

So light your set for 800 iso , if you start going to 3200 etc and higher you will get noise ! thats life!! so use the camera in its sweet spot 800 and under .

[M Carter]

22 hours ago, PannySVHS said:

Exellent statement. I think it is a pity that lighting sometimes is one of the most scaring aspects. It´s not scary at all though, it´s just scaring the heck out of us ambitious video lovers some times for no good reason. But it really is not such a big deal, if one has the chance to rent for little money or even buy or DIY.

Or utilizing natural light. It is really worth it for the fun of creating or sculpting an image with light, enjoying the process of creating and the possiblities of images and expressions.

The only problem with lighting is having lights. Well, knowing how to choose 'em and use 'em helps. I see so many posts from newbies trying to figure out which LED to get as their first light, and man... get on eBay and grab a couple used fresnels and a couple used open-faced lights, some bounce and some scrims. If you need daylight, you can usually get about 3x the power from biax flos than the same expense of LED. Look at Roger Deakins' forum - the amount of amazing work he's done with a couple redheads and a fresnel is amazing. And his rigs of porcelain sockets and household light bulbs. Sure, he's done plenty of work with banks of 4K HMIs and generator trucks, but the guy is a master-class in "use what works".

[TwoScoops]

On 14/07/2016 at 10:46 AM, funkyou86 said:

Your GH4 is not faulty. I'm having the same issue with mine. Just shot a video at night, and it's full of noise, I was shooting with ISO 400. IMO it's the downside of the MFT sensor, but I noticed that grading helps to smooth this noise out.

Here are some snapshots from my footages (straight from the camera).  The second one was shot in 4K, the first and last one in 1080p 200mBit/s

 

Sorry to be off topic. Just curious why you shot the first/last in HD instead of 4K? Is it becaue 4K can be unflattering (esp to females) so close?

[funkyou86]

1 hour ago, TwoScoops said:

 

Sorry to be off topic. Just curious why you shot the first/last in HD instead of 4K? Is it becaue 4K can be unflattering (esp to females) so close?

Because of the 60 fps, the camera was on a dolly and I needed the slowmo. At the second one I needed stability (more details later), so I mounted the camera to tripod, used 4K, then I added some movement in post without any loss of quality.

The video will be published on 30th of july. But right now I'm having some serious issues with grading, because Premieres lumetri panel is painfully slow, and the structure of the whole project is now so complicated, Resolve can't import properly the XML feed  So few more days to see what can I do with the noise and grains...

[JazzBox]

21 hours ago, andy lee said:

ps I always keep the g7 at 800 iso or under , I shot 80% of the Pandora movie at 800 iso and I went down to 640 for the rest of it , this film is mainly all shot at night there are no day scenes in the movie at all , so the G7 let me shoot in the low light 3 or 4 stops under exposed that I like to work at to get the look I use.

So light your set for 800 iso , if you start going to 3200 etc and higher you will get noise ! thats life!! so use the camera in its sweet spot 800 and under .

The problem with my GH4 is that I shot this video at 500 iso. Honestly it was the first time I had problems with noise in the mids.  
The histogram was "nice" (no black crushed out and enough highlights). Probably I had to check better the middle area, measuring the light on his face etc...
In the past I shot a lot of video at 800 and some at 1600 with the GH4, never had problems, for that I asked if my GH4 was faulty