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peterbkk

Member Since 25 May 2005
Offline Last Active Yesterday, 03:37 PM
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Topics I've Started

Nauticam Shogun Housing is here

06 May 2015 - 02:18 AM

It took a while for Nauticam to sort out a few issues but finally I received my Nauticam Shogun housing this week. I'm not going to write a full review.  I'll leave that to those better qualified.  But here are some photos and first impressions.  After a few days diving in Lembeh at the end of this month, I will give an update on how it performs in action.  

 

Of course, the Shogun monitor is great for seeing what you are shooting and being able to record ProRes HQ 422 10 bit video puts it into the realm of much more expensive systems.

 

Attached File  Shogun Housing.JPG   109.88KB   23 downloads

 

Firstly, the NA-Shogun is big.  Needs to be big to allow room for the Shogun, a big Sony battery and some cooling fans.  This system is not for the casual videographer.  However, with bigness comes stability.  The addition of this housing, line astern from the camera housing, will definitely help overcome some of the "pitch" stability issues inherent in the "still" camera format when shooting handheld video.  It also adds a lot more mass (but not in-water weight) - great for stability.

 

Secondly, it is well-engineered.  All the housing functions are available, except the menu - but then you should not need to play with the Shogun menu underwater. The function buttons give you control over focus assist, histograms, etc.  The "overhead" mount bar give a lot of flexibility for positioning. The HDMI cable seems to be solid - if you are careful with aligning the plugs.  It includes a full leak detection and vacuum system.  The base plate provides many options for mounting legs for macro.  Note: the housing does not actually connect to the base plate.  The overhead arm holds the monitor housing.  The base plate stops the whole rig from falling over with the weight of the Shogun housing.  It's also for connecting legs.  (Once I have worked out my preferred viewing angle, I might add a rubber-stopper to the base plate to give the bottom of the Shogun housing something to rest on - not necessary but might stop any wobble through the arm.)

 

Attached File  IMG_0194.JPG   111.43KB   21 downloads

 

Thirdly, it took me a while to get it set up the first time. But that's probably my incompetence - it's been a while since I played with Meccano.  Now that I know how to do it, I can get it done in about 20 minutes.  But, of course, you only need to set it up once at the beginning of a dive trip - you can do everything you need to do inside the camera housing and the Shogun housing with them all connected together.

 

Fourthly, unassembled, the GH4 in its housing / port and the Shogun in its housing, two video lights and their arms and some accessories all fit into a large carry-on size photo backpack.  No need to check it in.  If my checked luggage is delayed, I can still go diving and shoot, at least for a couple of hours.

 

Attached File  IMG_0209.JPG   92.89KB   22 downloads

 

The Shogun battery (Sony NP-970) lasts about 90 minutes of run time - maybe longer. There's space inside the housing to look at putting in an extended battery system for longer.   A 1Tb SSD holds 2 hours and 20 minutes of ProRes HQ 422 10 bit video.

 

This coming weekend I will test it in a pool (maybe my fish pond) and get the buoyancy and balance right.  I think that it needs a 1kg dive weight strapped under the rear of the rig - the Shogun housing is positively buoyant but the GH4 housing is slightly negative - together they still float.  A dive weight and a cable-tie should fix it.

 

Then it's off to Lembeh to see if it is worth the investment.  I'll keep you posted.

 

Regards

Peter

 

Attached File  IMG_0193.JPG   109.39KB   22 downloads


Tracking focus with a GH4 in the NA-GH4

04 April 2015 - 06:19 PM

Caveat: Maybe you all know about this technique and find this thread a bit "ho hum".  In which case, please ignore.  But, for me, it was an exciting breakthrough that improved my success rate shooting moving subjects.

 

Situation:

 

Panasonic GH4 in a Nauticam NA-GH4 housing with either the 7-14mm, 12-35mm (dome) or the PZ 14-42mm (flat port) shooting video of octopus, cuttlefish and squid in Lembeh.  I wanted to be able to shoot these critters "up close" and "on the move" but still keep them in sharp focus.

 

Problem:

 

I don't trust any auto-focus tracking system and have not had reliable success using it with the GH4 underwater, especially in murky conditions.  I prefer to use AFL/AEL to lock in focus and exposure for the whole clip.  With the camera set to AFS and a small centre focus point, I lock in the focus on the eye of the critter at the start of the clip.  But, then the critter starts to move.  How do I ensure that the critter's eye stays firmly in the narrow depth of field?  Obviously I need to move the camera with the subject, keeping the distance between the critter's eye and the lens at the same distance.  But that's quite difficult, especially checking the focus with the small monitor on the back of the GH4.

 

Solution 1 (attach a better monitor):

 

Use a large monitor that has built-in focus peaking like the Shogun.  But, Nauticam have not yet released the Shogun housing.  And I need to get the footage now.

 

Solution 2 (flip on the GH4's focus peaking): 

 

Unfortunately, the GH4's focus peaking only works when the camera is set to manual focus (Panasonic: could this be fixed in a firmware update, please).  The lens / port combinations that I'm using don't have manual focus.

 

But (and here is my big breakthrough), the NA-GH4 housing has a MF-AFC-AFS switch in a convenient location.  

 

Here's what worked: Before diving, turn on focus peaking in the camera's menu and save it to your favourite UW custom setting.  Underwater, set the MF-AFC-AFS switch to AFS and use the rear lever to set AFL to get a sharp lock on the subject's eye.  Flip the MF-AFC-AFS switch to MF.  The lens stays at the same focus distance as locked in.  But now the subject is also covered with focus peaking dots.  As the subject moves, move the camera with the subject, ensuring that the focus peaking dots continue to flicker all around the subject's eyes.  

 

If it's not moving too fast (e.g. an octopus walking), I was able to keep the subject firmly in the plane of focus (9 times out of 10)...

 

Regards

Peter


Sign the Change.Org petition for Bangka Island in Indonesia

10 January 2015 - 06:15 PM

I don't know if online petitions have much impact or not but maybe, if enough people sign it, the central government in Jakarta may pay attention.

 

Places like Bangka Island are unique and increasingly rare. We must save them for our children and future generations.

Anyway, I just signed the petition "Gov. @Sarundajang2014 & Bupati Sompie Singal: No mining on small islands. Save Bangka – North Sulawesi!" on Change.org.

It's important. Can you sign it too? Here's the link:

http://www.change.or...=share_petition

Thanks!
Peter


Video Light Filters

21 December 2014 - 02:31 AM

I mentioned in an earlier thread that I had been experimenting with some video light filters with the objective of finding a better balance between underwater ambient light and the broader (red) spectrum of artificial video lights.  Here is the problem, obvious in the screenshot below: the area covered by the video light has a lot of warm colour (reds and yellows) but the background is all greenish-blue.  Colour-correcting this scene is either a compromise or a complex exercise of selective secondary colour-corrections.

 

Attached File  No Filter.png   131.01KB   23 downloads

 

I think that I've found a cheap DIY system that can solve this problem and can be tuned to most underwater ambient light circumstances.

 

The main component is a 4x4 filter holder made by Lee Filters.  It's all plastic and rubber so nothing to rust. $20USD each at BH Photo: http://www.bhphotovi...4x4_Filter.html

 

Here is the holder with an aqua filter (the same filter that I used in the shot further below)

 

Attached File  IMG_1032.JPG   110.3KB   22 downloads

 

The slip-on rubber-band mounting system enables it to fit on most underwater video lights.  I use them on a pair of iTorch 7s but they also fit the Keldan Luma4s.

 

Here is folder mounted on the iTorch7.  It can be "wriggled on" easy enough and will not easily fall off - although I do take them off when getting into and out of the water so that they don't get bumped off.

 

Attached File  IMG_1030.JPG   108.1KB   22 downloads

 

The filters are pieces of plastic that I cut from document folders that I bought in stationery shops.  I wandered around a few shops until I had found a mix of light blue, dark blue, aqua (green-blue) etc. The firmer document folder covers work best.  I also cut some uncoloured plastic squares that are a neutral colour but make a nice diffuser for softer macro lighting for night dives.

 

You can take a few different shades of the colour filters on each dive but I find that I can usually judge from the surface what I will need.  The technique is simply to look at the colour of the water and select a filter that is the closest match.  If the water looks tropical blue, use a blue filter; if it looks greenish, use an aqua coloured filter.

 

So, here is the result.  This is the same scene as above, shot with the aqua filter on both lights then quickly colour-corrected in FCPX to reduce the green and boost the reds.

 

Attached File  Aqua Filter - Corrected.png   428.46KB   24 downloads

 

To my eyes, this image is very close to what it looked like underwater last week in Lembeh.

(the coconut octopus inside the drink bottle is guarding eggs and in the last few days of her life).

 

I have also used the same system in the deep blue waters of North Komodo, where a light blue filter worked best.

 

So for $40, some time wandering around stationery shops and a little bit of scissor work, you can make a video light filter system that will enable you to balance ambient and artificial light in most situations.

 

Regards

Peter


Results of my first commercial shoot with GH4

17 October 2014 - 08:32 PM

Here is an example of a GH4 video that I've just finished editing: http://www.peterwalker.com/komodo.html

 

It demonstrates the camera's capabilities both WA (7-14mm lens with Zen 170mm dome), Macro (14-45mm PZ plus flip Subsee +5 dioptre) and above water (12-35mm plus polarising filter).  I did all the editing in 4K and then compressed to 1080P just before uploading to Vimeo.

 

It was a pleasure to shoot and edit!

 

Regards

Peter

 

Thanks to David Cheung of ScubaCam for helping put the equipment together for me.