How could I have counteracted purple lighting?

Question

I recently shot an event using just a standard Nikon D3200 with kit lens. Nothing special, but it did the job.

The only obstacle was that the event made heavy use of a strong purple lighting which while easily correctable at the start of the night quickly became difficult to work with as the venue darkened through the evening.

I've cleaned up the shots the best I can, but a lot of the skin tones are still heavily purple and even with cleaning up people still look a little strange (see below).

I wasn't shooting using a flash, and I only had a simple UV filter on all night.

My question is as follows:

1. Is there anything I could've done at the event to prevent the purple tint?

2. Is there anything more I can do in Lightroom to reduce the purpling without leaving the people with a strange skin colour?

Answer 1

You need to adjust for the color temperature of the light source. Additionally. when the light source is of such a limited spectrum as appears to be the case here, you need to add more light that covers a wider portion of the visible spectrum. The relatively bright sky in the background fooled your camera's Auto White Balance into thinking that is what needed to be the correct color, not the much dimmer part of the scene in the foreground.

Here's the best I could do with the JPEG you uploaded as a starting point. If all of the information contained in a raw file were available, it could be corrected to a much better degree, but much of the information needed to fix the image was thrown away when the file was converted to JPEG either by your camera before saving the file or by you when you edited and converted the file later.

The problem with trying to change white balance with a JPEG is that you can only take away the parts of the color spectrum that you don't want that are contained in the JPEG. You can't add the parts that may have been in the raw data but were discarded in the conversion to JPEG and are not contained in the JPEG image. In the case of lighting that is very limited spectrum, such as appears to be the case with your purple light, you have to throw almost all of the light in the JPEG away to even get the color anywhere in the ballpark of realistic. That forces you to increase brightness to the point that almost all contrast is lost. Increase the contrast and all of the dark areas of the picture start going very dark again...

Here's an example I shot a while back of a band performing under limited spectrum LED lighting. The first shot is with Auto White Balance and standard Portrait picture style settings. If I had shot this as a jpeg in camera, this is what it would have looked like.

And here is what I was able to do using a raw editor. Notice that I didn't have to give up contrast and saturation to make a fairly significant correction to the white balance because not only was I removing information contained in the first jpeg that I didn't want, but I was also able to replace information I did need that was contained in the raw data but was not used in the creation of the original jpeg!

If you've never used a raw editor to adjust white balance before, look here. The instructions are for Adobe Camera Raw from within Photoshop, but Lightroom is very similar. And here's a video that covers both Lr and PS.

Answer 2

In case

• there are multiple crazy lights casting different tones from different directions;
• you only have JPEGs;
• or you just need a quick solution,

an easy way to fix color cast is to go for black and white.

Here's what I got in Gimp under a minute (Colors -> Desaturate -> Average), including some increase of contrast using Curves tool:

Answer 3

I think I would have used flash to overpower the extreme purple. But sometimes you can't do that, which can mean a lot of work in post. Here is what I would do in lightroom or photoshop camera raw. First thing I would do, which everyone else seems to have mentioned is to adjust the white balance. I then added a neutral gradient with even more white balance correction. Go into the HSL panel and move the purple and magenta luminosity up and the saturation on both of them down. From there I would use some radial filters to fix some of the underexposed people in the shot. Brightening there faces also has the effect of lowering the saturation of there faces. Next, I would add some noise and color noise reduction. I would go into the camera calibration panel and adjust the blue saturation to a negative value which will also have an effect on the purples and magenta; I used -17 in this edited picture. Lastly I would go into the split tones panel and add some orange into the highlight to give a more natural skin color. If you did this to a RAW picture it would come out looking okay, but not as good as just using a flash. If you were dealing with a different color you would have to adjust different colors in the HSL panel and the camera calibration panel to get the best results.

Answer 4

With strange mood lights, color temperature and tint won't fix it because it doesn't follow that pattern.

Your problem is that if you turn down the blue, you have an ambiguity in whether or not the object had any blue for real. Consider two shirts, one grey and one blue, that look the same under that light.

I had a similar issue a short time ago, with crazy colored lights in a hotel convention meeting room.

I started with the white eyedropper and fiddled with the sliders to get the skin looking something in the pink range.

I thought this was (still) terrible, but drew acclaim from others who were using just smartphones and "auto" white balance. :)

Then in PS I used the hue filter to adjust only pink to dial in the skin tone. I decided to go with a desaturated overall look to better deal with lack of strong accurate color: just use less overall!

Then move on to other identifyable colors: without uniforms, who cares if a shirt is purple or cranberry? You might not even know or recall. In my case, the green leaves needed to look like leaves, so I adjusted a hue range again, and happily this had no affect on skin tones so I did not have to mask.

You get the idea: fix the skin tone, then adjust hue on anything else that draws attention. Never mind if the rest of it is accurate, just unobtrusive.

If you have very low saturation in some colors (as explained above) reduce the others to match, or artisticly add them back in where needed.

Not shown here, I also that weekend completely replaced skin tone and clothes by using a Photoshop adjustment to paint color whike leaving the hue and saturation unchanged.

Answer 5

It looks like some of the people are wearing white shirts. You could use the white balance dropper tool in Lightroom - select it and click on a white shirt to set the white balance.

Answer 6

From what I see on the example you have wrong colour temperature/white balance. To avoid this you can use few ways:

• Make special presets in Lightroom with different colour temperatures and apply them (this work on jpegs also)
• Set colour temperature before shot. Here you can use custom set (shooting something really white and use this picture to tell camera this is white). Also you can set it by hand selecting exact number
• Or you can shoot in RAW and later in your post-processing software set the proper temperature
• Additionaly you can use so named "white balance filter". This will help you expose one image with filter and use this image as reference for in-camera custom white balance or later in post processing

To deal with the problem in post-processing

• open you image and use instrument to select object which is white
• or play with slider (of colour temperature) to catch the exact value which will give you the correct colours.

Also consider to use tint slider to "tune" the colours

Answer 7

As it has only recently become free, I'd now experiment with the Nik Collection (of plug-ins to LR and PS) - they do also work standalone. The collection is from Google.

It is early days practising here, but instead of using a WB blanket adjustment, start in PS / LR in RAW, then work in Nik, then return a masking layer from Nik into PS. Then you only allow the changes into the areas where you want them by painting the mask. I like the level of control of the image that is possible this way. I've some experimentation lined up. The jury is still out but so far the Nik approach looks a contender for the image problems mentioned in this post.