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Davide DB

Member Since 30 Nov 2010
Offline Last Active Today, 01:49 PM
*****

#392123 1 Inch ball mounts o-ring size

Posted by Davide DB on 07 February 2018 - 02:57 AM

Given that these oring are sold at outrageous prices, What's the size of these o-rings?

 

Thank you in advance




#391743 Lighting the scene

Posted by Davide DB on 26 January 2018 - 03:02 PM

Always on the same topic but with a more common approach.

These guys used a powerful HMI light to light up the wreck. More or less the same technique commonly seen in cave shots.



Rule #1 of these kind of shot would be "never use white tanks"

Imagine the same light from above lighting a portion of reef.

I wonder how many lumen output a light like that and how it compare with modern led lights. I used a Halcyon HMI light ten years ago and it was a nightmare.


#391680 Lighting the scene

Posted by Davide DB on 25 January 2018 - 12:20 PM

So when 4 lights are available you think its better to always split them with another diver assisting with lights. How about when one is not available? Still prefer to use just two lights?

 

Usually I bring with me the most powerful.




#391628 Lighting the scene

Posted by Davide DB on 24 January 2018 - 01:18 PM

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.

 

In conclusion... we never get bored underwater.

 

Bye




#391384 Panasonic LUMIX GH5 for underwater video

Posted by Davide DB on 19 January 2018 - 04:00 AM

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...


#391087 IS IT WORTH IT? GH5s - No Stabilization

Posted by Davide DB on 10 January 2018 - 03:28 AM

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:

 

https://www.reddit.c...gh4_for_in_car/

 

This is the source:

 

 

90% of my video are shot below 70m and since my GH1 I never complained about noise. I'm simply easy-going about it. I go down and shoot. Noise is the last of my problems. 

Regardless of own noise tolerance, reading this thread an average joe is under the impression that modern camera are useless in low light.

 

Byeeeee  :deadhorse:




#391039 IS IT WORTH IT? GH5s - No Stabilization

Posted by Davide DB on 09 January 2018 - 12:49 AM

Hi Mike,

 

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.

 

Bye




#391008 GH5S Rumours...

Posted by Davide DB on 08 January 2018 - 01:41 PM

Us mere mortals will probably stick with the gh5 tho.

 

 

I'm married with a GH3




#391006 GH5S Rumours...

Posted by Davide DB on 08 January 2018 - 01:18 PM

 

 

For everything else from here onward

 

http://www.personal-...ideo-edition/p6




#390980 GH5S Rumours...

Posted by Davide DB on 08 January 2018 - 06:40 AM

 

?

 

I'm finding my uw footage much much better with the use of IBIS.

 

 

Of course but it's something you can overcome with good technic and good balance as everybody else.

On the contrary, on land IBIS permits shots simply not achievable without a gimbal.

 

FInally more is better :)




#390971 Attaching a filter to Panasonic 7-14

Posted by Davide DB on 07 January 2018 - 11:54 PM

 

Getting two of these as want to fit one to 7-14 and one to 8...curious is fisheye works in fluro well ;)

 

 

Do you mean filter holder? Pana 8mm has already a filter holder on the back.




#390935 Editing- Music First??

Posted by Davide DB on 07 January 2018 - 02:11 AM

- first select the usable clips
- second you choose a music background
- Third you edit your clips trying to assemble a story or just a simple sequence that makes sense.

For a video with just a music background seems obvious to cut on the beat but actually it's not so simple. It depends.
Just have a look on this useful thread:

https://www.videomak...gainst-the-beat

Bye


#388611 Panasonic LUMIX GH5 for underwater video

Posted by Davide DB on 21 October 2017 - 05:12 AM

Welcome back!!!

How long it's been Wagsy!!!

You left me alone using Edius :)


#387978 On American and European documentary storytelling and our poor sharks

Posted by Davide DB on 28 September 2017 - 12:11 AM

This definitely gives me some closure about my ranting  :notworthy:

 

Legendary Sir David Attenborough, stunning images, Hans Zimmer and Radiohead soundtrack. What else?

 




#387963 4K to 1080 Pros & How To

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.

 

Thank you in advance