Jump to content
Sign in to follow this  
videodan

Expodisc White Balance Filter

Recommended Posts

thanks for that Nick, good job

Share this post


Link to post
Share on other sites

Hi Nick, great test. Too bad your results were not favorable. I wish I knew why others are not getting the same results as I get. I shot this Saturday in the Florida Keys on the wrecks USS Duane and the USS Speigel Grove, down to a depth of 99' (30M) and had excellent results. Perfect color and no browns. This is well below the depths where my camera can manually white balance without the Expodisc, so I couldn't do a comparison. I will try to do some shallower dives this weekend and do a test similar to yours so we can compare results. Maybe getting water in yours somehow changed how it works. Try sealing it up with a hot melt glue gun.

Dan

Share this post


Link to post
Share on other sites

Dan and Nick,

 

I have come to the opinion that WHERE you shoot has everything to do with how much you like the expo disk. I filmed in both Palm Beach and Bahamas and was very happy with my expo results. Even at 80 feet in the Bahamas i was able to achieve pleasing results with the expodisc (with and without cc filter). I used it in SE Asia (Bali and Raja) and was quite disapppointed. I used it at all depths and in sunny and over-cast days (in all the locations). Intersting...

 

The reefs in Florida and Bahamas are much less vibrant than in SE Asia. The water is a distictly differenent blue color in these locations. I can imagine the combination of water color and underlying reef color may explain the difference.

 

Nick, thanks for the comprehensive tests....gotta respect that kind of thoroughness. Also, glad you also find the hand works the best. My hand and "pink" slate are too of my favorite CC options. I also Use the surface as a mainstay. Perhaps we are closing in on a general set of principles for UW white balance with HDV that applies to most folks.

 

Shawn

Share this post


Link to post
Share on other sites

Nick

You get a big GOLD STAR for that...well done my friend. :(

Great work. :ninja::rolleyes:

 

WB on anything till one is happy with the colour and at the sun for deeper depths is my way and set it to auto db, exposure & shutter if it's having trouble at depth to get a fix then back to manual.

 

Have never used my own hand though...to WB that is :(

Share this post


Link to post
Share on other sites

interesting about the sun, i am never happy with the colours i get when i WB off the sun....

 

 

I much prefer my off white slate....

Share this post


Link to post
Share on other sites

Thanks for the feedback guys.

 

The great thing about using my hand is that generally I know where it is and it tends not to become detatched on entry. Plus with Shawn's "cuddle the housing" techinque it's less of a contortion than aiming the camera at a fin. With some housings I imagine white balancing on a hand would be impossible, unless you have 3 of them.

 

Should have really had a pink fin or slate in these tests for real thoroughness. Next time perhaps.

 

Simon, no I haven't yet, other than deciding I should dry the whole housing after each dive, not just the glass port. My old Stingray II housing has plenty of "build up" like that but it never advanced to what I would call "corrosion" so I'm not desperately concerned yet.

 

More results from different coloured water shortly...

Share this post


Link to post
Share on other sites

By the way, that first set of tests above was soon after midday and in extremely clear blue water well offshore at the Burma Banks. So loads of light for the depth and not really typical of the other dive sites in the Andaman.

 

I did a similar set of tests at 1pm in about 23m at Hin Taleh (Fan Forest Pinnacle) which is further inland in the Mergui Archipelago where the water was much less clear and rather green. Again the shutter was at 1/50 throughout and gain at 0dB except for one test where it crept upto 3dB.

 

This time the Expodisc performed much better and my favourite of the bunch this time would be the white balance on the Expodisc aimed towards the sun.

 

Again the three Expodisc results are pretty similar, indicating that it doesn't seem to matter much where you point it, it just refracts and averages the light passing through it.

 

White balance on the hand is my next favourite but not really green enough considering the conditions. Pretty good again though, and definitely passable if you don't have an Expodisc!

 

White balance zoomed in on the sun came out too blue and wishy washy for me this time.

 

White balance on a white fin was truly horrible this time. Much too red. In fact I think I'm basically going to stop using that technique completely as it hasn't impressed in either test. And to be fair, I had to reduce the red on most of the clips in my Reef Life DVD that were balanced that way with my VX2K.

 

So this time the Expodisc wins it, although I feel a similar result could probably be achieved with exactly the right tone of pink on a slate or fin.

 

So Shawn, looks like you're absolutely right in saying that the location and conditions play a huge part in whether the Expodisc is a benefit or not.

 

Dan, I doubt the repair changed the function of my camera. I didn't notice any difference before and after the repair. Likewise I doubt the partial flooding of the Expodisc has changed things much, but I suppose it's possible. Don't really want to seal up the edges yet just in case I decide to sell it.

 

Again the full res grabs, deinterlaced this time, are on my server if you wish to download them.

 

I did some more tests at Richeleu Rock. I'll check them out and post them up if they add anything to the debate.

post-3234-1174037395_thumb.jpg

Share this post


Link to post
Share on other sites

To be honest after trying different tactics myself and reading everyones points of view..

 

Wouldn't we say W/B and colour is all a bit circumstantial to where we are and also personal preference..What is the right colour..What I see or what you see..Or what the viewer will see.

 

If you get it close enough to YOUR personal taste then enhance it in post...Fair play.

 

We all seem to be looking for the one true colour..But is there really such a thing. I've seen so many variations on different programmes of what filmmakers perceive as good colour balance but sometimes it does not look right to me...

 

Will we ever be happy

 

Dive safe

 

DeanB

Share this post


Link to post
Share on other sites

I guess my aim with a lot of the heavily white balanced footage is to make the subjects in the foregroud look similar to how they would if they were lifted to the surface. But if you look at Mark's Palau turtle in the other thread, that looks great and is obviously not manually white balanced much, if at all. So yes, it's all subjective. If Mark and I tried a joint venture with our Z1 footage, we'd be buggered because nothing would match. Likewise if a third party sourced footage from both of us.

 

This exercise has been useful however to weed out techniques that obviously over-correct the footage or skew the colour temperature in the wrong direction. For example those overly red or overly blue results.

Share this post


Link to post
Share on other sites

Don't get me wrong big boy...

 

The tests you did were great and very informative..But I just think, as its been said, you'll get different variations of CC where you live and what conditions you dive in...If your happy with what you have achieved then fantastic..But don't fret to much..Results can be reached in other ways.

 

Dive safe

 

DeanB

Share this post


Link to post
Share on other sites

I found the tests very informative, and really appreciate your work to do them and post the results. A great learning experience.

Share this post


Link to post
Share on other sites

I thought I'd report back on my totally non-scientific tests with the Expodisc and my EVO housing.

 

As mentioned previously, my idea was to buy an Expodisc and then power-up my EVO/HC1 with it in place since I don't have MWB control with my housing.

 

So a couple weeks ago in Curacao that's what I did.

 

Unfortunately, the results for me were indifferent at best. I tried several tests while pointing at both white sand and the sun from around 60' during the startup process but I really can't say that I saw much of a difference.

 

There is a slightly more neutral tone to the footage shot doing this process vs. just starting up the camera without the Expodisc in place but it's more of a cooler, slightly greyer tone than anything else. The colors didn't seem to be much better in either sample. Based on previous results posted by others here I expected warmer, more lifelike tones using the Expodisc.

 

I suppose it's also possible that the whole process of starting up the camera in this fashion has some flaw I've not considered that precludes this idea from working.

 

And I only tried it one day, under semi-bright conditions, so there might be other situations where it would've worked better. The one day we had really bright skies, I left the filter in my apt...

 

Bottom line:

 

I have an 82MM Expodisc for sale in the classifieds.

Edited by sjspeck

Share this post


Link to post
Share on other sites
Can Amphibico add the MWB control option to your housing ?
Their solution is a mechanical button to press the assignable button on the A1U. But I have an HC1 - it doesn't have an assign button.

 

I knew that when I bought the EVO though. It wasn't until almost a year later that I decided to play around with MWB.

 

For what I normally shoot - clear Caribbean water, less than 90' - I'm finding that my HC1 does a nice job of Auto WB. And I can fix it in post....

 

I just saw a video posted by someone on another forum, their contention was that although they could "fix" the blue, they left it in since that was what they perceived while shooting. I think I'm starting to agree...

Edited by sjspeck

Share this post


Link to post
Share on other sites
Sign in to follow this  

Sponsors

Advertisements



×
×
  • Create New...