GH4 GH5 beats a7S, a7R II, GH4, E-M1 II, X-T2 & X-T20 in Low-light / hi-ISO test

joe12south said:
What does DOF have to do with low light sensitivity?
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For me I know that my "working" DOF with my GH4 requires me to shoot at f/2.0 - f/4.0, so switching to a FF camera would mean shooting at f/4.0 - f/8.0 to get the same "working" DOF that I am used to.

Sure you can shoot at wider apertures but will you get the shot you are after ?

I remember watching all these terrible videos when the Canon 5D Mk2 first came on the market because so many people were shooting almost wide open and it felt like my eyes had gone myopic because the DOF was paper thin and virtually nothing was in focus.
 
joe12south said:
Absolutely, but sensitivity *is* one of several key measures, and it is counter-productive to argue that it is anything but a weakness of the M43 format. The GH5 had to make herculean steps in terms of image processing in order to compensate. (And it does so amazingly well, IMHO.) But a camera with a better sensor could have spent that processing power on something else, so there is a price to pay.

I also find the argument that if you light intentionally (as we all should, even if we're using the sun) that there is not a benefit to more sensitive sensors. Ultimately, such a technology choice translates to creative choice. For example, if camera A needs a bunch of lights just to bring up the ambient levels to an acceptable point to then begin creative modeling, that camera has a time and money *tax* that camera B - which can work with the existing ambient levels - does not incur. The creative intent can be obtained easier and cheaper. That's nothing but a good thing.
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This this this. Creativity cannot be entirely separate from the technical end. Low light ability isn't just about being lazy and avoiding lights. It opens up whole new creative possibilities.
 
joe12south said:
I also find the argument that if you light intentionally (as we all should, even if we're using the sun) that there is not a benefit to more sensitive sensors. Ultimately, such a technology choice translates to creative choice. For example, if camera A needs a bunch of lights just to bring up the ambient levels to an acceptable point to then begin creative modeling, that camera has a time and money *tax* that camera B - which can work with the existing ambient levels - does not incur. The creative intent can be obtained easier and cheaper. That's nothing but a good thing.
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...But most cameras ( including the GH5 ) can work with existing ambient light, it's not having an existing key light that ALL cameras have to deal with. I shoot mostly educational and training videos with my GH4, and most of it happens in either offices or medical clinics. All of these environments have tons of ambient light ( and I can usually work with the existing color balance ), but they all need some key lighting to turn the existing "blah" ambient lighting into something better.

It's the people that claim to not need ANY lighting because they have a camera that is a low-light monster, that has never made any sense to me. Even if your key light is a rinky-dink little $50 LED light with some diffusion thrown over it, you still end up with a better shot, and you no longer require a "low-light monster" camera to get the shot.
 
DBP said:
This this this. Creativity cannot be entirely separate from the technical end. Low light ability isn't just about being lazy and avoiding lights. It opens up whole new creative possibilities.
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Yes but the Gh4/5 isn't a dark beast either. People kind of have this impression that it just cannot see in the dark and that is absolutely not true at all. Not even close. It may have a bit more noise at specific ISO levels but m43 is in no way horrible in low light. Compared to the 1/4", 1/3", 1/2", 2/3" and 1" markets m43 is actually a monster. At best APS-C cameras are a stop better. and that has mostly to do with more processing power used for noise reduction. Use a focal reducer and you eliminate that advantage 100%. You no longer get to claim the GH4/5 sucks in low light if it can do what most of the other cameras can do in the same kind of lighting with tools designed for those cameras to take advantage of. If one chooses to ignore using a focal reducer that is there own problem but when it comes to a m43 camera a user can choose to use it as is or gain an extra stop.

Yes using a focal reducer is exactly the same thing as having a larger sensor. It effectively turns a m43 sensor into a APS-C or super35mm sensor. Everything is equal expect for dynamic range and even that is debatable if it is only a by product of sensor size and not other factors.

I can be just as creative with a GH4 as you can with a larger sensor camera.
 
TheDingo said:
For me I know that my "working" DOF with my GH4 requires me to shoot at f/2.0 - f/4.0, so switching to a FF camera would mean shooting at f/4.0 - f/8.0 to get the same "working" DOF that I am used to.

Sure you can shoot at wider apertures but will you get the shot you are after ?
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No videographer experienced in low-light shooting would set a full-frame camera to f8 just to match the DOF of a cropped-sensor camera. In real life, you shoot at the lowest ISO your lens can handle while keeping your subjects in focus. DOF is not a fixed property of a particular aperture and sensor size, it varies with distance and is something you have to judge with each lens and the esthetics of each shot. If you're switching between cropped and full-frame cameras, you'll use crop factor to gauge which focal length to use, but DOF? That's a matter of camera and lens choice, available light is too valuable to waste on theoretical DOF calculations.

The 35mm full-frame photography standard is archaic and has nothing to do with video or cinema. If you want to emulate the optics of a traditional motion picture camera, APS-C is the closest sensor size to the Super 35 film used to shoot most 20th Century movies. Full-frame DSLR video became popular for one reason only - the Canon 5D Mark II. The extremely narrow DOF it could produce made its footage stand out dramatically from video shot with the tiny sensors in conventional broadcast camcorders. But it's an exaggeration of the cinematic look, and can be just as much a liability as an advantage. That's why many videographers prefer APS-C or MFT cameras for low-light event shooting, and reserve full-frame DSLR's specifically for wide-angle and portrait shooting.

It's Time to Stop Arguing About Crop Factors Already

http://nofilmschool.com/2014/08/crop-factor-sensor-size-zack-arias-dedpxl
 
Thomas Smet said:
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I agree Tony Northrup has some very odd methods of judging cameras and I rarely ever agree with anything he puts out there. I'm not even saying I agree with his methods in this latest comparison. I'm just saying that when one factors in a m43 camera they also need to factor in that is can use a focal reducer and can have access to very fast lenses like f0.95 primes. Tony also pointed out the fastest zoom the Sony can use is a f2.8 and that needs to be taken into consideration as well. A GH5 with a focal reducer and a f1.8 zoom is already 2 stops better than a naked GH5 compared to a Sony camera with a f2.8 zoom. That really does eliminate most if not all of that low light advantage. Of course it depends on the shooter and the situation but if one wants/needs to use a zoom lens then the GH5 can have certain advantages that people don't always take into consideration. Especially when you consider that GH5 setup will never overheat.
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Not sure who Tony Northrup is, but if he said that, he is just wrong. I use a F 1.8 zoom on my Sony all the time.
 
Lpowell said:
No videographer experienced in low-light shooting would set a full-frame camera to f8 just to match the DOF of a cropped-sensor camera.
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I know from 2 years experience shooting with my GH4 that pretty much everything I've ever shot with the GH4 has been in the aperture range of f/2.0 to f/4.0.

I rarely open up past f/2.0 ( mainly because my SpeedBoosted Nikon AI-S lenses suffer from coma at wider apertures and the image goes too soft ), and I rarely close down past f/4.0 because I normally don't want the extra DOF for my shots. ( I do for landscapes and cityscapes, but I don't shoot these very often )

For example, every corporate interview I've ever shot with my GH4 has been in this aperture range, with most of them shot with a 35mm lens. It gives me the look and the DOF I'm after. When I do a location scout I can quickly judge where everything is going to be set-up and what my background is going to look like. ( the background is never in focus )

This also works with my lighting, as I know how much power I need to bring with me for the aperture range I am going to be shooting at.

If I was to switch to shooting Full Frame I know I would be working in the same range, just closed down 2 more F-Stops to get the look and DOF I am after. ( and it would match how I shoot with m4/3 )
 
TheDingo said:
For example, every corporate interview I've ever shot with my GH4 has been in this aperture range, with most of them shot with a 35mm lens. It gives me the look and the DOF I'm after. When I do a location scout I can quickly judge where everything is going to be set-up and what my background is going to look like. ( the background is never in focus )

If I was to switch to shooting Full Frame I know I would be working in the same range, just closed down 2 more F-Stops to get the look and DOF I am after. ( and it would match how I shoot with m4/3 )
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Compared to nighttime events, corporate interviews are relatively well lit, typically needing only a key light for the subjects' faces. When shooting inside a performance venue, you have no control over anything and must be prepared for worst case lighting conditions. In practice, you want a stabilized f2.8 zoom, set shutter speed according to power line frequency, and shoot at the lowest ISO you can get away with. With a full-frame camera, you can shoot very close to the action with a reasonable focal length at f2.8-4. With a cropped-sensor camera you'll shoot from more of a distance, and you need f2.8 to make up for the light falloff. In both cases, DOF is a secondary consideration.

But WRT Northrup's GH5 vs A7R II comparison, sensor size is a red herring, because the A7R II has a perfectly good Super 35 cropping mode at 4K video resolution. There's no reason he couldn't have used the same lens and settings on both cameras and done a proper flat-playing-field test of the two cameras' DR and noise levels. Staging a rigged test at grossly different ISO settings with a speedbooster on the GH5 was a blatantly deceptive example of favoritism.

https://www.dpreview.com/reviews/sony-alpha-7r-ii/9
 
Thomas Smet said:
A focal reducer is one of the main key advantages to the m43 format. While m43 will likely always be slightly less sensitive than larger sensor cameras there is a lot that goes into sensitivity vs just the size of the sensor. The fact is the GH5 can already do some impressive low light shooting considering its sensor size and its secret weapon is the ability to use a focal reducer which more or less eliminates any low light advantage any other camera has excluding maybe the A7S which is a special snowflake.

We do need to factor in what a focal reducer can do in regards to low light because it is a realistic and intended mechanism for shooting with a m43 camera. m43 is basically a camera that allows us to get compact and eliminate any overheating issues but gain back what is lost by adding in a focal reducer. It essentially turns a m43 sensor into a super35mm sensor in every single way except for dynamic range. Not that a solid 12 stops is bad or anything.

So yes it is fair and realistic to think a GH5 with a focal reducer would match or beat most other cameras out there in low light. What sliver of an edge other cameras may have is for an unrealistic shooting situation and negated by all the other advantages the GH5 brings to the table.
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Very well put!

A focal reducer can make even the old Panasonic GH1 do better than expected, beating out a 5D mk2 which still goes for way way way more secondhand.


filmguy123 said:
I agree Thomas.

And not just focal reduced lenses, but also great glass such as the Voigtlander kit (workable at 0.95 and sharp at 1.2) among some other options.
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Plus the SLR Magic T0.95 lenses.

And the Veydra primes which are quite fast for cinema primes, and waaaay smaller and cheaper than anything else like them.
 
dustylense said:
Then you're not using FF.
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Correct, I'm using Super 35. Which was what I said earlier when it was
said that m43 had some sort of exclusive advantage because they could use a
speedbooster. I was pointing out the fact that Super 35 shooters can also use a
speedbooster. Yes, it's a little different because instead of going from m43 to Super 35
(which is what a m43 speedbooster does basically) a Super 35 speedbooster goes from Super
35 to FF. Then there was some talk about how Sony cameras couldn't use a zoom that was higher
than a 2.8. Maybe something was lost in translation. But basically, I am saying that
m43 does not really have some 'big advantage' over Super 35. FS5 or 7
(or A6300 or 6500) users can use speedboosters, or zoom lenses that are faster
than 2.8 just as easily as m43 users can.
 
Whooptiedoo. So what. Good low light capability has nothing to do with sensor size. Yep, nothing. Larger size? So what, if I can compensate with superior sensitivity and computational power. Larger size is always better? Err, no. There are limits to what the human eye can perceive and post production needs. For example, the human eye can perceive about 20 stops or so. So if you have sensor A that does 25 stops (say), and sensor B does 30 stops, for most film/video applications (I'm not talkin stuff like scientific applications) sensor B is not superior. You do reach a limit beyond which you don't need greater capability for a given application. If you are doing talking head interviews for corporate videos, the low light capability of an A7S is plenty - if someone says "but A7SIIIIII has 20 times better low light ability!" you are not going to care. Of course, if your applications are astronomy, maybe it makes a difference.

So too here. The fact that the m4/3 is smaller than FF shouldn't matter at all when it comes to low light. Have you noticed that sensors are getting better all the time? I have no doubt that one day - probably fairly soon - there will be an m4/3 size sensor that gives you as much low light capability as you're likely to need for most film/video applications (barring scientific applications and the like). Now, the GH5 is still not there. The tech needs to get better, but it's not completely out of sight. Probably by GH7 or GH9, they'll actually have no questions asked max low light capability, DR and so on that nobody is going to compete on that and point to FF - m4/3 will be all you need for the kind of work people on this board do. We're definitely not there yet. Sensors need to get better. Who knows, maybe in 5 years it'll be here.

Today, to get real low light out of the GH5 you need all sorts of tricks and add-ons like speedboosters. Tomorrow, you'll be able to do it natively without any assist from special external gizmos.
 
OldCorpse said:
We're definitely not there yet. Sensors need to get better. Who knows, maybe in 5 years it'll be here.
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I'd go one further to say that the next generation of sensors will probably get us there. BSI alone, nevermind the other patents that have been published, can push the M43 sensors into the realm of better light gathering than the human eye.
 
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