David, I agree with your point of view. What do you mean by the last part “ light from ABOVE emulating sunlight”?
Let's see if a mod can split this thread
On WA shots I used to place my light arms more or less at the same height of my camera. Now I try to place them higher than my camera trying to have a light angle coming from above. I like the shadows I get. Of course every reef is different so your mileage may vary.
Now I have 4 lights. Two old Keldan Luna 8 CRI (5K lumen each I guess). Two prototypes built by a friend of mine (12K lumen each). I never mounted them together. IMHO I would get a correctly exposed flat image, nothing more.
When a keen buddy is available I give him the most powerful set. I fill the subject in front of me with my Keldan and my buddy "flies" 1,5 meters above my head trying to light up the scene/subject from above. Then we play with different angles.
I find that in this way you get amazing shadows. Sometime we get a sense of depth impossible to get in other ways.
Sometime we try a different approach: I light up part of the scene in front of me filming my buddy which in turn light up further far away. Sometimes we get clips we like a lot, sometimes just trash.
This video was made from two dives we experimented a lot this technique. I made a lot of mistakes (i.e. I left my lights on while being well far away from the subject getting only a lot of backscatter. The Gerardia Savaglia was completely burnt on the highlights cause I haven't zebra on my GH3) nevertheless you can see several examples of what I'm trying to explain.
The amphora at 1:12 and 1:24 is light up from my lights and from my buddy above. The same scene at 1:30 is light up only by me and as you can see it's not simply a matter of exposure. The clip at 1:12 has a completely different depth of field.
We used the same "tricks" on most of the clips of this video:
You can see what you can get on a big sponge light up from the opposite at 2:13.
Again the small gerardia savaglia from 2:40 is light up from above even in the close up clip.
At 3:22 you can see my buddy moving upwards while I film the small dendrophyllia and you can see how the reef appears under this kind of light.
At 4:29 an example of me lighting up part of the scene in front of me while my buddy, in turn, lights up further far away. We gently move together giving a great "sense of depth" IMHO.
I understand that I have very particular tastes for UW imaging. I do not pretend to be mainstream and sometime I'm very contentious here
Once you have several lights and some collaborative buddy you can be very creative.
I have just started experimenting with 4 lights so my experience is really limited and don't even know if i am using them the right way. I actually searched online for guidelines but was not able to find something.
Anyway i am using the two Keldans mounted on long arms at the handles ball mounts and the two sea dragons mounted directly (no arms) at the left and right tripod ball mounts of the Nauticam GH5 housing. I was having the sea dragons positioned parallel to the housing. Next time i ll try to mount them on short arms and position them lower that then housing. That might work better for wide angle shots away from the bottom. Of course there is no recipe covering all scenes and only with experience might get somewhere meaningful
I see some JJ GUE configured there hence teamwork should not be a problem.
Try to experiment giving a couple of lights to your buddy...
Ok, we steered from IBIS to high iso/low light capabilities
Sorry to be a bit rude on this I think "noise at high ISO" is a debate since the camcorder was invented. Actually IMHO a moot point. We are discussing of scrren doors on a submarine!
Please define e x a c t l y what is your definition of noise. Please give me a real example, a link to a clip useless because of high iso noise.
Since I started filming underwater I read countless posts, articles on this topic. Whatever camera you pick, there will be always someone who find high iso unacceptable. Based on internet pixel peepers opinion we would have ZERO movie/documentary produced since the invention of Netscape because quality is not enough. This is demonstrated and documented by bazillion of bushes filmed on the backyard.
I wrote this provoking post after reading this comment "And yet 20-year-old film students who don't know how to light still complain because the camera is grainy in low light" on this thread:
It would be better discuss this on the video & gear sub-forum cause this on is more targeted on photography so probably you will get more in topic replies there...
Anyway. This is a pro video camera. While it comes out form Panasonic consumer division it shares a lot of features with Pana EVA camera.
Pro video cameras don't have IBIS.
Camera IBIS it's not a firmware feature or upgrade. It's an hardware feature so you will not get it via a sw upgrade.
There is a valid reason they did not equipped this video camera with IBIS: sensor temperature. In layman's term, in body image stabilization on these beast is obtained physically moving the lens or the sensor.
This brings two problems: AF performance issues and higher sensor temperature (ask Sony about camera temperature while recording high bitrate at 4K).
As you can see from specs and test in both cases the GH5s perform better than Gh5. Af is better because sensor is steady and sensor is cooler which means bigger DR/cleaner image.
Finally, IS IT WORTH IT?
Nothing personal. Actually I see on the net thousand of nouvelle Christopher Nolan and Howard Hall that cannot express themselves without no less than a Red.
Basically if you have a Gopro, a used GH4 kit is for you and for 90% of us. If you have the budget or you are a gadget-addicted (like me) go for a GH5.
Posted by Davide DB
on 27 September 2017 - 06:16 AM
I'm starting to experiment with a GH4.
Right now I'm just interested in a 1080p output but a lot of doubts and questions arises...
On several articles and posts on the net I read that converting from 4K to 1080 results in a far "better" image and colors. IIRC I even read that I could get a 1080 4:2:2 clips from a 4K 4:2:0 clips. Mumble Mumble...
Could you elaborate on this and share your current workflow?
If I'm not interested in crop i could create a 1080p project and throw 4K clips at it.
I could create a 4K project, eventually take advantage of some crop and finally export everything at 1080p.
I made some test with the two above scenarios and frankly I couldn't find substantial differences between the two. I use Edius so I have no transcoding. I just edit directly the original 4K clips as usual. Of course the 4K project is slower than the 1080p one.