GH5 for video documentaries: some questions please.

[Adriano Moroni]

I understand!! GH5 is not for me. I need to buy a better videocamera than AX100 but a small videocamera like it. I think there are'nt videocameras with a really better image quality than AX100.

[Pete Cofrancesco]

I think your quality issues have more to do with your setup or lack of. If you want to show up to someone’s house with a consumer camera and use little to no setup with existing light you’re going to be limited by the amount of quality you’ll be able to achieve. When a subject is properly light they look good with most any camera. If you’re comparing your quality to what you see on tv... they have an experienced crew with cameras costing more than $15k

[Noa Put]

I am not sure the GH5 is that much better in low light than the AX100, noticable but neither is stellar in really low light.

What lens do you use on your GH5? The difference in low light performance is considerable if you use a f1.4 lens, if you use a 12-60 zoomlens that is f4 at the longest reach then ofcourse there is not that much difference.

[Alastair Traill]

I have come to this thread rather late and I am surprised at the overall view that you cannot zoom with a GH5. Surely the ability to hold focus during a zoom is dependent on the lens and not the camera? The lens has to be parfocal and very importantly set up at the correct distance from the sensor. My stills camera (Nikon D300) died suddenly recently and I have replaced it with a GH5. I now have 2 zoom lenses for it, the Leica 12-60 mm, f2.8 and the M-Zuiko 40-150 mm, f2.8. My preliminary tests indicate that both these lenses are parfocal. Also at one stage I had a GH4 and a Nikon mount Sigma 18-35. This lens was parfocal on my Nikon but initially non-parfocal when used with the GH4 by means of a cheap Nikon /MFT adapter. To correct the problem I combined a couple of cheap adapters to make one that was deliberately too long. I then laboriously shortened it on my lathe by removing 0.0005” at a time reassembled it and tested it with an auto collimator. I repeated the process several times until parfocality was achieved.

[Noa Put]

When I zoom in with my 40-150, lock focus and zoom out slowly I see that the lens is loosing focus at the start of the zoom and I see that it does correct after that, this is a behavior I have never experienced with any of my videocamera's that had a fixed parfocal lens, eventhough there is some correction going on with some lenses to make it appear parfocal one cannot expect to buy a dslr and some zoomlenses that are designed for photography and expect all to behave like a real parfocal lens, something to keep in mind when you transition from video to photocamera's. Also doing controlled zooms can also be difficult and depends on how smooth the zoomring and doing controlled variable speed zoom is nearly impossible.

[Ron Evans]

Almost all new camcorders with fixed lenses have the ability to slow controlled power zoom and certainly with auto focus will hold focus completely. Doing this manually with a GH5 is almost impossible. So if this sort of action is needed then not something that is going to work well. However shooting in UHD and then zooming and panning in post can be much smoother and more controlled than doing it manually. That is how I use my GH5 too.

Yes Noa using my 12-60 set at about 18mm to fill stage ( about f3.3 max ) is a little better than the AX100 but not startling better for low light. It has a lot more dynamic range so does manage the stage lights noticeably better. However my goal is to get everything on the stage front to back in focus so having a lens wide open would also not be what I want. I am after max depth of field ( I know, opposite of what a lot of people want from the camera ).

[Pete Cofrancesco]

Only cinema lenses are truly parfocal by their physical design. For these other lenses the camera is using software to auto correct to simulate parfocal. The 12-60 is variable aperture and a bit slow.

[Mark Rosenzweig]

To summarize what has been said, succinctly.

Zooms on camcorders have two advantages, not one:

1. Parfocal - no slip in focus or refocus while zooming.

2. Power zoom, variable speed, for smooth zooming.

There are NO lenses for mft cameras that can do 1 and 2.

On the other hand, there are power-zoom, essentially parfocal zoom lenses available for Sony mirrorless cameras. And the A6500 AF is far better than that for any Panasonic.

I do not get why anyone would consider Panasonic cameras who wants a camcorder experience (there are very good reasons to choose them for video other than that).

If you want a bigger sensor, excellent 4K, power zooming, and excellent AF ..look at Sony.

[Ron Evans]

But none of them do 50/60P UHD GH5 is the only one to do that and that is why I have it. 4K for me is 60P so none of the Sony's do that. Well the FS7 does but that is different range I think.

[Noa Put]

Originally Posted by Ron Evans

Yes Noa using my 12-60 set at about 18mm to fill stage ( about f3.3 max ) is a little better than the AX100 but not startling better for low light.

I think you should always mention f-stops when you say there is not much difference in low light performance because otherwise you are providing misleading info that makes it appear that a gh5 can't do much better then a 4year old ax100 in low light.
That f1.4 or faster lenses might not work for you for stageperformances I can understand but it is at least an option if you need to shoot in very dark places, the difference between f1.4 or faster lens and f3.3 can mean having a usable or unusable shot which is an advantage you can have with a gh5 but not with the ax100. The gh5 can shoot in low light conditions the ax100 can't.

[Ron Evans]

Yes agreed, the advantage the GH5 has is one can change the lens for a faster one. With similar iris values the GH5 advantage over a 1" sensor like the AX100 though is not that big. Pixel size and noise reduction starts to play a role too.

[Pete Cofrancesco]

What it really goes to show is that what you are filming and how you want to film should determine what camera you use. People common complaint is this camera is terrible in low light. The follow up question that comes up compared to what? A camcorder is terrible vs micro 4/3 but a micro 4/3 is terrible compared to full frame. But in video there are many factors other than low light performance that are just as important so we can go round and dissecting the technical aspects but without knowing the intended use and style of the original poster it’s quite pointless.

[Ron Evans]

You can look at Adriano's WEB site to see the sort of video he shoots. He travels light I am sure since these places are remote. I think to improve over his current work will require more effort than an automatic camera . In focus and well exposed the AX100 produces nice video. Not sure what improvements he is looking for in a new camera. However one that is easy to use in his environment is the issue for him. I think he has to decide whether he wants the convenience of a camcorder or the control in a higher end camera with multiple lenses etc. He has not raised the issue of whether he is trying to meet a spec for sale of his video for instance which would have a definite influence on equipment choice both for video and audio.

[Noa Put]

but a micro 4/3 is terrible compared to full frame

That again is not always correct, "full frame" does not automatically mean a lot better low light performance, the canon 5dmark2 also can shoot video yet it won't outperform a panasonic gh5, a canon 5d mark 3 or 4 could also be considered "terrible" low light performers when compared to a sony a7s yet both are full frame camera's.

There is more to it then just having a full frame sensor that determines a camera low light performance.

[Pete Cofrancesco]

Originally Posted by Noa Put

That again is not always correct, "full frame" does not automatically mean a lot better low light performance, the canon 5dmark2 also can shoot video yet it won't outperform a panasonic gh5, a canon 5d mark 3 or 4 could also be considered "terrible" low light performers when compared to a sony a7s yet both are full frame camera's.

There is more to it then just having a full frame sensor that determines a camera low light performance.

I could have said the A7 but I didn’t want to ruffle your feathers. ;-)

My beef is with people who make unqualified statements about this camera is good or bad. Then compare it to something that is older or more expensive or completely different category of camera. So if you want talk about the latest 5d vs the A7 then great similar sensor, price and style sure let’s do that. Otherwise it’s a bit like saying hammer is better than a screwdriver or a sports car is better than a suv.