This post is a guest post from Bart Zoni who has the website, see more ways to contact him below.

Ever wonder how Sports Illustrated gets those awesome skies in their outdoor portraits? This easy and inexpensive trick will set you on your way to awesome vibrant skies in outdoor portraits just like the pros – without a ton of Photoshop work. So, I hate editing photos. Any tricks that can help me get awesome photos in camera are always at the top of my list. If you want awesome, bolder skies in outdoor portraits without having to “mess with the sliders”, here’s what you’ll need:
1) A decent sky with some color in it. Blank overcast days are a no-no for this trick. I like blue.
2) A camera that allows you to shoot RAW or adjust white balance in camera
3) A decent flash – preferably one that allows for higher sync speeds
4) A few adhesive Velcro squares
5) Color flash gels – you can get individual ones for $1-2.00 each or this complete set for around $16

The first thing is to get your strobes ready. You can use off-camera flash or on-camera, whatever you like, but you have to be able to attach colored gels [kind of like specialized cellophane] to your flasheads. I keep one “hook” type adhesive Velcro square and one “loop” type square on each side of my flash head. I do the same to all my color gels [see photo below]. This way, you can easily pop the gels on and off your flash heads. +10 eccentricity points if you keep all your gels in a small photo album, labeled neatly. [Yep, you can be obsessive compulsive Leica BOSS, too]

You’ll need to set up a photo with both a subject and a sky. I like that nice azure blue sky you get before sunset for awesome “electric” blue results. The shots here are pretty lame, but show what’s going on pretty nicely.
Here’s the deal:
1) Set the camera to manual – this makes it so much easier
2) Expose for the sky, I like to underexpose a little bit to ensure the color saturation is good. Below is a photo with about the exposure I want for the image without using flash .

3) Obviously the subject is too dark – this is where the flash comes in. I used automatic flash metering (iTTL, ETTL, etc.) dialed in at -2/3stop exposure compensation to get the results I liked. Getting this right may take some trial and error – but you basically want to balance the sky (ambient light) with the subject (flash) so the image doesn’t scream I USED A FLASH PEOPLE! Here’s a shot taken with flash – no other funny business and the white balance set to “FLASH”

adding flash

Adding Flash to the portrait

4) See how the colors in the sky haven’t really changed in the first two photos – but the subject is now well-lit. This is where the fun comes in. Pop on a color gel. What color? Well, without going too much into color theory – pick a color that’s opposite the color of the sky on the “color wheel.” In the case of a blue sky, that would be orange-to-yellow. I used a Color Temperature Orange (CTO) ½ gel. Here’s the result:

flash photography

Adding a colored gel to the flash

5) What did this do? And why does it look awful? Well, the sky is pretty much the same color as in the prior photo because the flash certainly doesn’t reach that far – but you can see a difference in the subject’s skin tone – and even some orange in the t-shirt. In the photo above, the white balance is still set to “flash” so the camera is expecting the flash to have a cool natural color but we fooled it with the gel. Now he looks like an oompa loompa. More on color temperature at Wikipedia or Creating The Correct White Balance In Camera.

6) So, now, we want to “fix” the color temperature so the subject appears more natural – and has skin tone similar to the photo taken with the flash but no gel. To do this, in Lightroom, I used the eyedropper to take a “white balance” reading off of the collar of the t-shirt. The color temperature went from 5200k, -2green to 4100k, +6magenta. Here’s the result:

gelling flash for creative portraits

7) POW! Now the subject’s skin tones are back to normal, but the sky has taken on this nice saturated, electric color. No sliders, no other funny business. Just one click of the mouse (or pentablet, Mr. fancypants). It’s really that simple to get really awesome deep blue skies. You want to go really nuts? Try a deep amber gel like this:

gelling flash for blue skies

By “washing” your subject in gel-colored light, then setting white balance based on that light, you’re basically fooling the camera into modifying the colors in the photo that aren’t lit by the flash.
Normally, blue skies actually have loads of “red” in them. But you can’t just move a global slider in most photos to only punch up the skies without impacting parts you don’t want to change.

Below, you see 4 crops taken from the skies of these test photos taken with different gels, and setting the white balance accordingly to each.

The first photo is taken without a gel – notice the average color has a red channel value of 61. That’s a lot of RED in a “normal” blue sky. When you add a BLUE gel to the foreground (second color from the left), you actually end up making the sky MORE dull and dreary – see how the blue channel went from 144 to 90? Booooo. Orange is opposite from blue on the color wheel – when you counteract an orange color cast using white balance, you’ll get more pure blues in other areas. Notice in the last 2 images that there’s almost no red left in the sky and when you use that ridiculous orange filter, you have a pretty saturated rich blue sky with no red channel at all.

This also works in other kinds of light. Have deep orange skies in a sunset? Pop on a blue filter and intensify those oranges. Want a creepy look in fluorescent light? Pop on a light pink filter and see the results.
This can be a lot of fun – takes only seconds to get done – and almost no time in Photoshop to give you great results. Happy shooting!

Article by Bart Zoni
Gear, rants and tutorials about life, photography and shooting Leica BOSS.
Twitter: @TheLeicaBoss
Flickr: bartzoni

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