Green Magic

[johnny boy]

The green water filter is what i've been waiting for ages! Thanx Peter for being so inventive. Has sir Alex Mustard had a part to play here?

The thought of being able to crank up the ISO setting on the camera, jump in with just the housing and no strobes has me reaching for my gear! I intend to go for a D200. Whats the noise like at say 1600 ISO? I can't help thinking that the Canon 5D would be better noise wise, but maybe not have as much 'support' in terms of all things underwateresque. I dunno.

If only i was sat under the bows of james eagen layne now, looking 'heavenwards' through my viewfinder......

[PeterRowlands]

Hi johnny boy
Sir Alex M is indeed involved. He came up with the formula and made me start diving in the UK in March testing variations. Diving without strobes is great but the GreenWater Magic is not intended to replace them. It is just another tool/technique in the underwater photographers toolkit.
My Nikon D70 is pretty awful at 1600asa so I'm hiring a Canon 5D outfit and will do some side by side tests in the next couple of weeks and post them here.
Best wishes
Peter

[KenByrne]

Tim, If I understand correctly manual white balance alters the way in which the camera firmware interprets the recorded data, it does not change the way in which the data is recorded.

If I'm right this has an important benefit when shooting RAW. If you have RAW files for the Green Magic shots you should be able to set a manual WB in post processing. For example on the Staingarth shot try using the dropper on the pale area around the windows.

[TimIngmire]

Hi Ken,

I probably wasn't clear above.

The first set of shots are jpg's straight from the camera using auto WB.
The 2nd set of shots are RAW's which have been WB'd in Photoshop and with contrast and slight tint correction according to my own tastes.

With the filter in place the colour is rebalanced to a certain extent (especially when deeper) meaning that you don't need quite the same amount of post-process correction which IMO makes the photos better.

HTH

Tim

[KenByrne]

Hi Tim, I hadn't spotted the second set of prictures in the gallery.
This is interesting but I'm not totally convinced. You can do a lot just by adjusting the white balance without the filter. No doubt the filter does a great job under the right conditions but it imposes limitations (light loss menaing lower speeds or higher ISo and no option to use flash). That said the price is very low compared to most UW photo kit so I guess I'll be ordering some and giving it a try.

Ken

[Alex_Mustard]

Hey Guys,

Peter sent me a link to this chat to see if there was anything I'd like to add. Embarrassingly, I must start by holding my hand up and say that I have not actually shot the Greenwater Magic myself. Yes I am a big wuss.

I agree with Ken that you can do a lot with just WB. And certainly this can give pleasing results at shallow depths. Although these results are rather less pleasing when you seen the images taken with a good filter.

The advantage of the filter is that unlike using just WB - that merely processes the data collected by the camera - a filter actually modifies the spectrum of light entering the camera so it is more balanced. When this is processed it produces a much better looking image. Furthermore the filter helps to maintain a rich water colour (as filters darken the water relative to the subject), which WB alone cannot.

Alex

[Alex_Mustard]

One other curious thing we have noticed with the Greenwater Magic is that it can be hard to match the look of a JPG straight from the camera by WBing after shooting in Adobe Camera Raw (the Photoshop plug-in). When Peter first told me about this I put it down to his lack of ACR skills - but I had to eat humble pie when I found out that I couldn't exactly match the files!

My explanation is that at higher ISOs the camera are doing a considerable amount of in-camera processing of the images - which cannot be reproduced in ACR alone (you need a bit of Photoshop too). I suspect that Nikon Capture could produce the same look (as a JPG from a Nikon camera), but it is so user un-friendly when it comes to setting WB that you would probably die of old age first!

So, to get to the point. With the Greenwater Magic filter it is important to set the WB in camera and to shoot Raw + JPG as sometimes the JPGs from the camera produce superior looking images that cannot be easily matched in ACR alone.

Alex

[TimIngmire]

Hi Alex,

and welcome to Digigreen.

The rebalancing argument is probably the most convincing argument for those that can shoot RAW - I, like many others, still like to try and get the colours and picture right as it hits the CCD and so making the job of post-processing less onerous (although we may not be that succesful).

What was interesting of course was that even with just the jpgs, the colours were much better, although there is clearly a limit to how shallow you should use the filter. I guess many people will be happy to make that shallow water sacrifice given the better result that get at the depths they will mostly be diving ie. over 6m.

I've been impressed with the performance of the original Magic filter on even basic digicams and it looks like the Green version is capable of vastly improving pictures in the same way although maybe not quite to the same extent (thats more my feeling than through direct evidence).

Do you see any changes between this latest beta and the final filter?

Tim

[KenByrne]

Following on from what Alex says I've noticed a difference between the way that Nikon View (a free download from the Nikon site) and ACR process RAW files. For example the in camera settings such as Vivid colour seem to been taken into account by Nikon View but not by ACR.

I rarely use Nikon View because it has so little control compared to ACR. However I've just been trying it out on a few available light shots. The tool that seems to produce the most interesting results is the auto contrast with colour change. The colour change gives a good approximation to manual white balance, although sometimes the result of the contrast change is a lot of noise and colour banding around highlights. I think it would be worth trying this tool on a few magic filter shots.

Ken

[DuikKees]

Great efforts Peter, the tests look promising.

I wonder how the filter works in really low light conditions.
Because I am thinking of when I would use the filter and that will be times when strobes are too much hassle, suchs as rough boatdives and wreckdives on the North Sea which are all at 30m.
How do divelights come out?

Cherio,
Kees