Water too blue - How do you correct?

[Geoff F]

A common problem for me. At certain angles to the sun water turns a dark unnatural blue colour. Filters etc don't appear to make a lot of difference.

Over the years, I have tried many editing remedies but can't really find anything better than a little tweak of the Blue Channel using Curves; and sometimes a tad of Red increase.

Using the Selective Colour control and very slightly adjusting the CMYK Neutrals also works sometimes - but I am getting a bit out of my depth now.

Curves plus a very tiny twist of Selective Colur can be beneficial on difficult photos.

I'm using Serif Photo Plus X2, a mid range editing programme.

So how do other people deal with this frequent problem?

Example of typical problem photo attached, but at least in this case the main subject isn't going to be badly affected by the 'cure'.

[Henry Peach]

That looks like glare to me. A polarizing filter should help.

[Dave Humphries]

That was my first thought too Henry.

Of course, the downside is that losing a couple of stops is the last thing you need on a long lens for shots like this

That may make it impractical.

Geoff,

I assume it's mainly a problem on sunny days with (reflected) blue skies?
On an overcast day, if there's enough light and contrast to shoot, I would imagine it's not a problem.

Regards,

[Hansm]

I opened your file in Lightroom and noticed the colourtemp was 5000K.
Was this the correct colourtemp or is this a seting in your camera?
If you increase the colourtemp you will notice that the total picture gets warmer so blue cast disappears.
Is the orignal a RAW file or do you shoot directly in jpeg?
With RAW there is more flexibility in adjusting and get rid of colourcast.

[Colin Southern]

As a starting point I'd suggest shooting a spectrally neutral gray card to use as a white balance neutral reference. AWB isn't always overly accurate in these types of situations.

[shreds]

Geoff F,

When you say 'too blue', would you prefer it to look something like this or am I barking up the wrong tree?



(Tweaked this one using Nikon NX2 utilising colour control points).

We have lots of muddy water and overcast days here!

[Geoff F]

Thanks for the ideas so far.

Firstly don't get too worried about this particular photo; it is just an example of a common problem which I often get when taking water based subjects and I know that a lot of other photographers get even worse difficulties.

So I intended this to be a general discussion of the subject in an attempt to help other photographers before the summer sun causes frequent similar colour cast problems.

I'm not too sure of the exact scientific explanation but this effect occurs when the light is behind you and at a certain angle. Low waves can produce a strange light and dark ripple effect which sometimes produce a banding between blue and a brownish colour particularly with dirty muddy water.

However, lets try to find the best solution. As Dave says, when using a long handheld lens for this type of shot or when shooting from a boat, a polarizer often isn't practical. And I can't say that it has really helped when I have tried this.

As Hansam remarked, increasing colour temperature does help, providing you don't overdo it, so yes I tend to mostly shoot RAW and increasing the temperature to somewhere between 6500 to 7000 during conversion does partially work. Images still require a bit of colour editing afterwards but a lot less. When the camera angle is constantly changing I generally prefer to use Daylight or Auto, etc, at the time of shooting, unless it is a static subject. The photo example is straight from the camera using AWB.

I totally agree with Colin that a Custom White Balance is the only way to get true colour, but it is rather impractical when shooting from a moving boat with changing angles and much the same applies to wildlife photography, particularly when trying to remain hidden. But it is a good idea for some landscapes, etc.

Shreds's example has gone a little too far but the idea looks interesting. It is estuary water which is a bit of a greenish grey colour with a hint of blue and the mud should be a greyish brown but not dark muddy brown. It can't be far off though because the bird's plumage looks about correct.

Hopefully we, and other readers, will manage to learn a little bit more from this discussion.

Geoff.

[Colin Southern]

I totally agree with Colin that a Custom White Balance is the only way to get true colour, but it is rather impractical when shooting from a moving boat with changing angles and much the same applies to wildlife photography, particularly when trying to remain hidden. But it is a good idea for some landscapes, etc.

No no no - it's just as easy in these situations; all you're trying to do is to work out the colour temperature of the light - if you're shooting from a boat, just shoot the gray card from somewhere in the boat - just so long as it's not being illuminated in any way by indirect light reflecting off something - changing angles doesn't enter into it. Same goes for shooting wildlife.

Temperature changes quite rapidly at dusk or dawn, but mid day you'd only need to reshoot the card every hour or so.

[Geoff F]

When saying changing angles, I was meaning more about the boat direction rapidly changing when trying to get the best angle on a subject, which is also moving around. And the problem of excessive blueness in the water also keeps coming and going as the sun direction varies due to the boat direction. But in general I do agree with you Colin.

However, actually carrying and then holding the card in a small moving boat, say 10ft long, can be a bit tricky during windy weather; and that doesn't allow for trying to steer the boat as well. Possibly a roll up or fold up version, but would that lay flat enough? Something for me to think about there.

In reality I have often found that an old white hankie makes a reasonable easily transportable alternative. My white hankies, after being used as oil cloths, bandages, hand towels etc then washed with mixed colours, soon become about the right shade!

[Colin Southern]

When saying changing angles, I was meaning more about the boat direction rapidly changing when trying to get the best angle on a subject, which is also moving around. And the problem of excessive blueness in the water also keeps coming and going as the sun direction varies due to the boat direction. But in general I do agree with you Colin.

Sounds like your boat is about the same size as mine!

Keep in mind though that the changing angles that are giving you differeing amounts of blue aren't related to changes in colour temperature - so it doesn't affect white balancing per sec (the camera is still faithfully recording what is seen) - the problem is just that what it's seeing (and you're seeing too) is not what you want.

However, actually carrying and then holding the card in a small moving boat, say 10ft long, can be a bit tricky during windy weather; and that doesn't allow for trying to steer the boat as well. Possibly a roll up or fold up version, but would that lay flat enough? Something for me to think about there.

Doesn't have to be big - even something the size of a matchbox is fine (off memory, I think the white balance eyedropper in ACR only samples a 5 x 5 pixel area, but could be wrong). Doesn't matter if it's not flat - only thing you don't want is to have "dirty light" falling on it from reflections from surfaces within the boat.

In reality I have often found that an old white hankie makes a reasonable easily transportable alternative. My white hankies, after being used as oil cloths, bandages, hand towels etc then washed with mixed colours, soon become about the right shade!

I did not just read that ... I did NOT just read that! Seriously, materials like that can throw the colour off due to the presence of UV Brightners (to give the "whiter then white" look) - and they can suffer from metamerism - but theory aside, if they work then "go for it" (I've often used something similar or worse!). Coffee filter has also been suggested by a few.

[Dave Humphries]

Coffee filter has also been suggested by a few.

Previously enjoyed, of course!

[Geoff F]

While we are talking about coffee. I have heard people say that they use the piece of white card which fits inside the lid of a jar of instant coffee. Most versions are about the right shade but, so far, I haven't tried that method myself.

[Colin Southern]

While we are talking about coffee. I have heard people say that they use the piece of white card which fits inside the lid of a jar of instant coffee. Most versions are about the right shade but, so far, I haven't tried that method myself.

Often things like that are quite close enough, but from a "purist" point of view they may not be spectrally neutral, and there's no gurantee that the colour of the reflected light will change to exactly match all temperatures of the incident light ... but in all likelyhood would probably be just fine.

I use a whibal card just so there's "no surprises".

[shreds]

White balance cards such as the expensive Whibal or the reasonably priced Digital Grey Kard (just Google them or find them on ebay) can be as small as a credit card and just need a quick shot that can be used later in your workflow. They do make larger versions too, which might be of less use in the boat, but are very good in the studio etc.

My only concern, Colin, is that there may be reflected light off a boats' interior that could affect the reading, compared to a shot into the water. (Of course since my DGK is plastic, I suppose I could float it in the water!

As with the example I put up, it was a quick and easy fix during the workflow. If I had been there I could have related the colours better and then adjusted accordingly. The software did all the work.

[Colin Southern]

My only concern, Colin, is that there may be reflected light off a boats' interior that could affect the reading, compared to a shot into the water.

That's why I mentioned it twice

[shreds]

Too many posts...too much to read....time to go and do some photography!