Tag Archives: Adobe Lightroom for underwater photography

Correcting an Underwater Image Taken Without Flash

My underwater image of a tiger shark swimming over eel grass needed some processing to make it into something worthy of the cover to Underwater Photographer Magazine Issue #97

Here is how I used Adobe Lightroom  to get it ready for the cover.

Images taken underwater without a flash will have a color cast due to the loss of the red spectrum of  light as it travels through water.

This is a method I use to process my photos that adds back in some of the red and corrects for exposure.  I prefer to leave a bit of a blue cast to the images – they are depicting underwater after all. The trick is to correct it to a point between what your brain saw during the dive and what is technically “perfect” according to the color values.

I use the tools in Adobe Lightroom to do the initial work: they are great tools and easy to use.  I might move later into Photoshop to utilize layers for adjustments to specific areas taking advantage of layers, masks, etc only offered in Photoshop. I definitely will do more detailed work on the image before printing it.

By the way, Lightroom tools are the same as in Camera Raw, but I find LR’s presentation of them easier and I have the bonus of all the organization tools in LR.

The Method

Analyze then Correct Exposure

The first step is to optimize the exposure.  I like to eliminate the distraction of color so I can really analyze what needs to be brighter, darker, and more contrasted.  To do this I temporarily desaturate the image to black and white using the Saturation Slider (Basic Panel under Presence)

 

Desaturate image
To concentrate on the Exposure and Contrast, convert to Black and White (desaturate)

 

Now it is time to analyze the image:  The Histogram is the first step.  According to the graph, there are clear shadows, midtones, and highlights,  but the whole image is too dark: there are barely any areas registering on the right hand (bright) side of the graph.

Exposure: I move the Exposure slider up until the lightest bits of water  read around 62 (pass the curser over areas and read the numbers under the histogram).  The overall change was +.55

In Lightroom the group of tools under Exposure (Highlights, Shadows, Whites, Blacks) are adjustments with smart logic behind them that helps the tool adapt and decide what is “whites” or “blacks” in this specific image.

Curve adjustment tool
Pick up the Curve Adjustment Tool and pass it over the image to read exposure values and see it on the Curve graph

For this purpose they are not doing exactly what I want so I will try the tools under ToneCurve first. Tone Curve is a degree more sophisticated and gives me the option of defining what I want to be considered Highlights, etc.  In this tool, Highlights, Lights, Darks, and Shadows are marked by regions on the tone graph.  I want to adjust the pointers to change the default “definitions” of Highlights, etc.

Curve adjustment
The image after a Curves adjustment

The dark edges of the fins  need some contrast between them and the lighter colored body. To do this I first measure the value of the darkest areas watching where on the graph this area registers by picking up the tool at the top left of the ToneCurve (“adjust the tone curve directly”). I want to define everything darker than the “spots” of the body as “shadow”  so I move the marker at the bottom of the graph over to the this spot on the graph.  Now the Darks tab needs moved to the left. Using the slider for Darks you can detect what it is adjusting – I want it to just do the spots on the body and tones on the fins.  Same with the Lights tab. Lights should be  working on everything light except the shark’s belly and some of the sand and fish.  I have now defined my exposure areas. It is time to make the adjustments.

Now I add a touch of the Clarity slider to pop the midtone contrast – this really brings out the stripes on the tiger shark.

Local adjustment brush
Adjustment brush used to brighten whites and highlights on the shark’s belly and face

For spot exposure corrections, Lightroom  has a Radial Filter tool which can brighten or darken an oval area in the same manner as a graduated filter or a free form brush type tool that can “paint” on adjustments.  I find the radial  tool better and easier to use than the Adjustment brush.

Correcting Color Using White Balance and HSL  Panel Controls

return color
The image has better contrast but still a color cast

Everything is brighter and more contrasted,  the colors look  more intense, but the color cast is still there.  I use the White Balance eyedropper tool and pass it over the image.  You want to choose a place that Should Be either black, white, or neutral grey.  In the Navigation (on the left fly out panel) window it shows you a preview of the white balance correction if you click in that space. When I choose a spot on the belly of the shark it makes the correction, but it is too much for my taste. After the correction,  I back off the sliders under White Balance a little bit back to the left toward the original cool tones.

White Balance adjustment
Use the White Balance tool on the shark’s chin – the change is too extreme but we will adjust it down
back off white balance adjustment
back off the White Balance adjustment by moving sliders back toward blue and green

Now I have the problem of the water not having as nice of a color – it has gone a bit dull –  so I go down to the panel labeled HSL/Color/B&W tools.  I like the presentation of the tool that they label Color,  so click on where it says Color and the tool changes to show each color and all three characteristics under it: Hue, Saturation, and Luminance .

Dropping Saturation on the Aqua slider a bit helps  the  color cast and increasing the Luminance to +20 helps the contrast as well.  On the Blue slider I increase the Saturation to make the blue water pretty again and then a decrease of the Luminance darkens the water and makes it a richer tone with more contrast to the whole image.  I also push the Hue of the blue up a tiny bit  without going too much or the water becomes purple. Since there is quite a bit of green in the image, I darken then Luminance on the green channel, desaturate it a touch then shift the Hue slightly to the yellow side of green.

Color adjustment HSL panel
The HSL color adjustment panel and adjustments to Aqua (desaturate), Blue (darken and move toward purple) and Green

A few final touches:  use the adjustment brush on the shark with some desaturation and white balance adjustment to take some Aqua/Blue out of the shark.  Also edit the first adjustment to the white belly and chin that you did earlier to add in desaturation to move the white closer to white.  The final adjustment is a tiny bit of the Dehaze tool.  This bumps up the contrast and intensifies the colors.

Dehaze adjusment
Final image with a small Dehaze adjustment and a little Post Crop Vignette

You can also add a bit of   Post Crop Vignette to darken the edges.

 

Also See:

Tiger Shark & Hammerhead Dive 2017

Using the Shadows / highlights command in Photoshop

Tiger Shark and Hammerhead Trips for 2018

 

 

 

 

 

 

Using Lightroom with Underwater Images: Exploring the new Dehaze Tool

Introduction

The newest release of Adobe Lightroom CC 2015  has a new tool called Dehaze which is stated to “dramatically improve images by removing haze”.  I have been wondering if this tool is applicable to underwater situations that mimic haze (scatter and low vis).

In this demonstration I take a pretty good underwater image that feels a little “hazy” or “Milky” and apply the Dehaze tool like a secret weapon to see if it improves the sharpness of the image.  I also compare it and combine it with the Clarity tool – another finishing touch secret weapon.

The Original Image

(click on photos to enlarge)

starting image of a whale shark
The image before I begin

The Image with some Exposure, Curve, and Color adjustments

 

Exposure corrected image
The image after apply some exposure, curve, and color correction

 

Adding the Clarity Adjustment

image with Clarity added
The image with a Clarity adjustment

As per my usual method, I add the Clarity adjustment to the image right at the end of my process.  The Clarity slider adds mid tone contrast, lending a sharpness to the image.   I don’t normally Sharpen beyond the default setting unless I am presenting elsewhere besides on screen.  If it is to be viewed very large or printed I get serious and sharpen in Photoshop.

Clarity settings
The Clarity setting – also shows my exposure adjustments done previous

I used a fair amount of Clarity to pop out details on the whale sharks face.  It is a good effect and I am happy with the results.

Also you can see my Exposure settings from the beginning of my processing which back off the bright highlights (the white upper lip near the surface) and boosts some contrast in the mid tones on the body by separating Shadows and Whites, and adding darkest tones by decreasing the blacks.  Not seen here are further adjustments to the Curves to manage the Highlights,  but that is a different topic.

Using the Curves Tool in Lightroom

Color Correcting beyond the White Balance

Trying a Dehaze Adjustment

dehaze setting

With a just a Dehaze adjustment – clarity set back to zero

Adobe Dehaze adjustment
The Dehaze setting

Dehaze was a bolder effect, but similar to a Clarity, but I see a slight “enriching” of the colors as if the smarts behind this tool also effect a certain color range.  I like the effect, but might have to follow it with a small color shift and a brightening of the water to maintain the contrast between water and shark.

A Similar Tool that does the Opposite – Luminance Noise

noise in the water
Detail of the water showing noise

Getting rid of Luminance noise is effectively doing the opposite of what the Clarity and Haze are trying to do: add contrast vs remove contrast.

Luminance Noise is common in images taken in the dark. Underwater photos have scatter which in many cases can be treated like Luminance noise.  There is also Color Noise,  which can also happen in (commonly green) water, it is harder to fix.  I applied a pretty heavy Luminance correction to “smooth” the water and remove what manifested as grain in the water.

apply Luminance noise adjustment
Water detail with Luminance Noise adjusted
Luminance noise adjustment
Luminance Noise adjustment settings

The Luminance Slider is the amount of effect to apply

Detail is like telling what size of speck you want the tool to act on

Contrast is telling the tool how different the luminance of the speck has to be in order for the tool to act on it.

These tools take some trial and error to get it smoothed to your taste without going overboard and making it look smeared.

It will not work on all photos unfortunately and in extreme cases you will have to resort to blurring, masking, and advanced tools in PhotoShop.

You can also try the Adjustment brush to a specific area with the Clarity set to a negative value – anti clarity which can work like a gauze effect.  I may explore this in another post one day.

full image noise
The full image with just the Luminance Noise adjustment – Clarity and dehaze off

 

End Results – Luminance Noise Adjusted Water plus Clarity only

full image with clarity and noise adjusted
The full image with noise adjustment and Clarity

 

End Results – Luminance Noise Adjusted Water plus Clarity & Dehaze

noise, dehaze and clarity
Image with Luminance noise adjusted, with Clarity and Dehaze added

End Results – Luminance Noise Adjusted Water plus Clarity & Dehaze and a brightening of the water

Final Result
The final result – I added a small increase in Luminance in the Blue channel to brighten the water

To put back some brilliance in the water that the Dehaze took away,  I brightened the water only in the Blue color channel.  Any adjustment including just midtone adjustment would have effected the results of Clarity and Dehaze on the  black, white, and grey colored whale shark which is where I wanted it.  I dont need the technique on the water and it is uniquely blue compared to the whale shark, so using the Blue Luminance on the color channels allows brightening just in the water.

My conclusion is that i will use the Dehaze tool  and further explore situations where I can use it.

Also See:

Guide to Photographing Whale Sharks