How to light with Colour Gels

The Beginners Guide to Lighting with Gels

I hear you ask. Well, there's no better place to be than here. I'm going to make this as simple as possible and I’ll try and avoid jargon throughout. Do you want the simple guide to something seemingly very complex? Perfect. This isn’t going to have obnoxious graphs with technical terminology, just real solutions to common problems. So if you want to take photos like this, but don’t want to look at equations or charts, read on.

I’m gonna walk through the entire process of shooting this shot with Ivana:


So lets start - here are the five ‘rules’  that I use to ensure I get consistent results in the studio when lighting with colour gels.  

1. Attach the Gels
2. Position the Lights.
3. Light the Background. 
4. Light the Subject
5. Rim light the subject. 

It’s as simple as that. The devil’s in the detail, but you’re onto a winner with this plan. So let’s start. Before we get to the fun stuff, you’ve got to know how to get the fiddley things that are gels on to your flash.

How to attach colour gels to lights

This might seem simple, but before we talk about anything else, you need to know about physically attaching the gel to the light. Gels are just sheets or rolls of a coloured plastic that withstand heat better than the average plastic. If you want to know why attaching them correctly is important, look through the recent additions to the hashtag #colourlights or #jakehicks on Instagram. You'll see a lot eager amateur and hobbyist photographers pushing out a lot of washed out shots. The greens aren't really that green, or the background is a hodge-podge of colour and murky whites. There can be a variety of reasons for any of these (more on that later), but the prime suspect is poorly attached gels. Here are two example from my first attempt at colour gels with the amazing Merrin back in 2017 that didn't go too well:

There’s a lot wrong with the lighting here, to be honest - but the gels were nowhere near being correctly attached. Check out the bottom left hand side of the picture on the right. There’s a big, glaring white spot where the gel had slipped. Not good. (Incidentally, I reckon Merrin is one of , if not the best models I’ve worked with - so after this poor work from me, I was delighted I didn’t let her down on our last shoot here)


You might be surprised at how slapdash the gel attachment process is. There’s no seamless rig available for all lights or softboxes/umbrellas just yet. Sure, you can buy some handy rigs for speedlights, but for the bigger lights, it’s all gaffa tape and elbow-work; Homemade rigs and hope. You just bury your head into your softbox and tape that gel/filter up. You have to make sure however, that no white light is getting through.

If you’ve got a modelling light on your flash, it’s a godsend. It’ll show you how well you’re doing (check out that green lit softbox - no white light is getting through - it’s smooth and consistent). Common sense would dictate that if there’s a gap between your bulb and the subject that the gel isn’t covering, that ugly white light is gonna get through and muddy your lovely colour.

It’d seem like the most simple solution would be to just attach the gel to the bulb right? The problem what that is that a lot of people report that gels can melt onto the bulb. Which is not ideal. Bulbs get very hot. These things are essentially plastic. It’s not a winning combination – especially if youre using the modelling bulb. Avoid burning down the house / inhaling toxic fumes by using a workaround. Cover the inside of a softbox with a roll of gels. Make sure the gel covers every inch to the edge. Move it closer or further from the light source if needed. This way you can make sure no white light gets through without burning yourself alive or giving yourself toxic lung. And what more could you ask for?

Okay, so you’re now covered in gaffa tape or a few quid lighter having bought the speedlight option. What next? Lights set up.

Where do I position the lights?

Where you position your light is going to affect everything. It’s arguably the most important thing you do for this whole plan. Here’s a picture of where I set up my lights for the shoot with Ivana. Click the images below to expand.

So, before any shoot I like to use the Set.a.light.3D Basic software to create a lighting template. It’s a fairly nifty piece of software that can help put together the technical aspects of any shoot. I export the setups to my phone and use them to help steady the ship when I’m setting things up. You can see what the flashes impact will be - and mock up a shoot before executing it. I think that it’s a great way to not get overwhelmed by all the technical possibilities on the day. I don’t use it as a sacred text and if something isn’t working, or if I’m struck by inspiration I can change things on the fly - but if you’re serious about the studio and have €60 ready to spend, I’d recommend checking out the trial first at least.

So I mocked up a lock and it needed four lights. The Background Light, the Key Light and the two Rim Lights. You can perform this type of work with two light sources, but I’d recommend at least three anyway. Let’s look at where I positioned the lights - and importantly, why I did so.

Your Background Light should touch the background only – it shouldn’t light the subject in any form. You can see the background light to the right of the Ivana in the sample image. It’s behind the her (so that it doesn't spill onto her), aiming towards the middle of the backdrop behind. In this instance, I’ve used a large Octobox. You should get a nice flat even light from it.

Your Key-Light’ should light up the subjects face, but shouldn’t bleed onto the background. I’ve prevented this by using a beauty dish with a grid. The grid controls the spill of the light - it will only go where you point it. It’s up high too, pointed down to mimic the sun and present visually-pleasing light. I normally put this very close indeed to the models face. Maybe less that 2 ft away. The closer it is, the greater the fall off will be - thus keeping it off your background. If you want to get technical and learn more about this, check out the Inverse Square Law. You can see in the image that I have it to the right of the camera - and I get Ivana to look into it. If I wanted her to look the other way, you could keep it where it is for some short-lighting, but you may notice that my subjects are always looking into the light.

Your Rim-Lights should shape the back of the subjects head, without glaring into the camera or ruining the background. You can’t really see it in the image above, but there are barn-doors on the light on the left - and a carefully crafted piece of, eh, cardboard on the one one the right. Hey, it works. It ensures the light doesn't spill anywhere else. I normally have these at about 30-45 degrees to get the best effect. You dont want them side on, as they’d get light onto the front of the subject. Instead, position them to the back and behind so that they pour over the shoulders. I usually push these far enough out so that they’re not visible in the frame.

The next step is settings - camera settings, not light settings. We’ll get there shortly after though.

Settings for colour gels Photography

What settings should I use? I hear you wail.

Simple. Get your camera settings to where you want them to be first and adjust your lights on the model around that. What does that mean, you say?

Well, say you know you want a shallow-ish depth of field on your subject, then dial in a wide aperture like f/4 or f/2.8, even. Or perhaps you know you’re gonna have some action in the studio - someone jumping about, for example. You’ll want a fast shutter speed to capture this motion without blur. If these were the case, you’d set your settings to accommodate those first. The idea should dictate the shoot - not the lighting power. You may run into some technical limitations, so know what you want to do - and see if your equipment allows you to do it first.

No, seriously. What settings should I use?

Okay. People get hung up on ‘correct settings’ as if there’s some golden rule to it all, some secret society of photographers that create and withhold the truth about how to set up a camera correctly. It’s just that ‘correct settings’ don’t exist. What’s the correct gear to be in when driving? Well that depends whether you’re on a motorway or reversing around a corner.

If you’re really stuck however, there are some common settings that many people use as a jumping off point. So if you’re really at a loss, use these at a beginner’s template.

ISO – 200
F / 8
Filetype: Raw

These settings will stick you in a safe middle-ground. If you want to know what settings you should be at to then accomdate a faster shuter speed or shallow DOF, these would be helpful as a tool to adjust also.

Power settings for studio lights

Okay, I said I was going to make this easy and take away all the technical jargon and get down to the most simple form of it, right? Well, the good news is, the hard work is already done. Given that you have now dialled in your camera settings and positioned your lights, you can set your lights to a power that is visually suitable. You have established a scene, you’ve reduced all the possible variables - things are now set. This is great, because now lighting is as simple as dialling up the power, or turning it down as needed.

I feel that due to the wide array of flashes, all with varying power outputs – as well as all the possible distances of the flash from what it’s lighting, that there’s no point whatsoever about talking about what power setting your flash should be at. Full power on a Godox AD-600 is wildly different to full power on a Nikon SB-300. Light the way you want it to look. How you should want it to look is darker than you’d expect.

For me I always aim to have the image slightly underexposed. Get it about a stop or a stop and a half under. Use your histogram to get yourself in the right area. Or aim for it to look somehting like this:


If you have all this done and are mindful of what you want as the end result..

Lighting is now simple

You've created boundaries in which your lights will fill. You have your cameras settings dialled in and positioned your lights accordingly. You also know you want to light to a slight underexposure. So really, you don’t have much say on light power at this stage; by working to this template, you’ve taken out the technical nonsense - you know what you have to do. You’ve done the hard-work, you can now adjust to taste.

It’s a game of individual adjustments until they're where you want them to be. Let’s start by looking at the background light.

Lighting the background

I start with the background for two reasons. Once it's set up, you don't need to touch it again. It’s done. You know that it's right, so you can concentrate your efforts on adjusting the key light if and when your model moves. Secondly, I always find the background light the most fiddley to set up. You can use the time that your model/subject is getting ready to sort out the background. You can create a setting into which you can plonk your sitter.

You don’t want your background light too close to the background. You’ll end up with an image like the below left. See how it goes from very bright, almost white on the right hand side to total darkness on the left? Not good. I move it a bit back (and switched sides) and tried again. That’s the picture on the right. It’s better, sure, but it’s not great.


As the previous under-exposed picture of Ivana shows, you'll want it flattened it out. To do so, just keep bringing the light back a little further - And stick it in a softbox. A big one if possible.

I use a large softbox/octobox where possible for this. It give a large, evenly lit background surface. As previously stated, I underexpose by a stop on the background too. Underexposing  maintains more detail in the colour for when you open it in Photoshop later on. And when you’re dealing with images like these, Photoshop makes it possible to make beautiful colours all the more blisteringly bright. It also has the additional benefit of helping separate the subject from the backdrop that bit better when the rim lights are thrown in.

So that was easy, right? It only gets easier

Lighting the subject

Lighting the subject is a doddle now too. There are some things to be aware of though.

As stated previously, I'm a fan of putting my key light as close to the models face as is possible. This creates a quick “fall off” (i.e. the light lights the face, shoulders etc but has essentially disappeared by the time it gets to the hips etc.). This helps in to avoid throwing colours onto the background too. The aforementioned grid also prevents spill here too.

You can literally light by sight again. You’ve your background correct, your settings all dialled in, so adjust your key light settings as needed. It really as as simple as this. Again, you don’t want to overexpose – if you do you can lose detail in the skin. Your overall image should be fairly underexposed and in a future blog post, I’ll show you how to work the Photoshop Magic.

Remember to light the background first. Then your subject. You're building a scene, not flinging bricks together and hoping they build a house.

Rim Lights

Providing you've positioned your rim light/s as outline above, setting them up is as simple as adjusting the power until they’re where you want them to be.

Unlike the key light, I tend to keep the rim lights flat. I don't point them up or down and I keep them at about shoulder level. I want them to Light the edges, and if they were high, pointed down, they could potentially spill over the shoulder.

And that's it.

Simple right? Hopefully it was understandable and easy to follow for you, but if there's anything missing or that needs expanding, let me know in the comments below.

I’ll be doing some deeper dives in future posts, but this should get you started and set you up for your first jump into Colour Gel Photography.


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