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Vancouver Colour Consultant: How Light Affects Paint Colour

By 01/18/2012October 7th, 202140 Comments

I am getting lots of questions about lighting and how it affects paint colour. I’m including this one to start off this post because it’s even more complicated than the usual one I receive (and it’s a great question, thanks!)


“Maria, do you know of a seminar that would delve into the more technical aspects of colour: how do certain chemicals affect the colour, how will this be reflected in light and environment; the different aspects of light and environment that affect colour, for example. We’re really hoping to find a course more specific and technical – ie: to know WHY the colour reacts in different environments?”

Before I distinguished the different undertones in complex neutrals I was obsessed with understanding how exposure, light bulbs, outdoor reflections like water bouncing off an ocean or lots of green trees would change the paint colour in a room to something that makes you want to run screaming in the opposite direction, or move house.


In fact I recently conducted a colour consultation with a client who hated the colour in one room in her house so much she was quite convinced she should move. This is how powerful colour is and this is why we lose sleep over getting it right.

But I digress.

It was at the same time that I obsessed over trying to understand Metamerism that I started working with large samples.

This (and the thousands of consultations I did) was how I learned that there was a finite number of colours that worked 95% of the time when I needed the right neutral. And it was how my system that I teach to homeowners and designers was born.


So here is the scoop on paint colour and what happens to it:

Light Source Information:

Morning Daylight – Cool daylight absorbs the coolness and shifts color towards warmer pigments.

Strongest Daylight – Very bright direct sunlight washes out colour and lightens and whitens it.

Fading Daylight – Mixed light cancels both warm and cool shifting color duller and neutral.

Artificial Night Light – Warm lights absorb warmth shifting it to cool pigments.

Effect of Natural Light Exposures on Colours

North – Adds Blue and overhead skylights dulls colour

East – Adds Green

West – Adds Orange

South – Adds Yellow-White and washes out colour

When I first learned all this I studied it and tried to wrap my head around it, but my best advice would be this: if all you have to work with when choosing colour for yourself or your clients is small paint chips then yes, this might be useful because now you have to try and predict what the colour will look like because you certainly can’t see what is happening to it with a small colour sample.

Yes, I know you still test the colours but it’s painful to specify 2-3 colours for your client (or for you), test them and then discover they are not even remotely correct because it was too hard to tell in the first place if you were even close.


For example, remember this consult in Atlanta I did last year? Crema Marfil in two bathrooms, one with natural light and one without. Perfect example of what I’ve just been saying.

It was working with my large samples that taught me undertones so that I can teach you. To this very day if I hold up a large paint sample and the lighting in the room is causing it to look greener, yellower, bluer, pinker, more orange or purple than usual, it’s easy to tell right on the spot. I then just tweak it by pulling out a warmer or cooler one, depending on what is required.

I asked my group of Certified True Colour Experts on our private facebook page today if they are less obsessed with understanding how lighting affects colour now that they have the big samples and this is what Heidi Nyline said:

“My ever-growing collection of big samples allows me to ignore/forget/not care about all the things I am supposed to know/learn/understand about colour and light. All of that is just theory. Whatever. You put a big sample up and it either works or it doesn’t work.”


And to answer the question at the beginning of this post? No. I don’t know of a course that would give you that (although I’m sure they exist). Everything I’ve ever studied gave me theory (see above examples) which did not help me when I was trying to figure out which paint colour was right in any given situation.

And just in case you think this post is written just to sell my samples, not true. I pushed them this hard in my courses long before I found a supplier to make them so that you could buy them. Get your assistant to paint them up for you, whatever it takes, your world will change once you have them in your back seat for your house AND for your clients.

One more thing, if you have just read the technical lighting part above and have questions? I am not the one to ask, it will hurt my head.

Related posts:

Why is it so hard to Choose Yellow?

A Light Colour will Never Come to Life in a Dark Room

Effect of Natural Light Exposures on Colour

If all this hurts your head too, download my eBook here and it will make a lot more sense!

If you would like your home to fill you with happiness every time you walk in, contact me.

To make sure the undertones in your home are right, get some large samples!

If you would like to learn to how choose the right colours for your home or for your clients, become a True Colour Expert.

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  • haha, you make me laugh, maria!!! great post – sometimes it is what it is and it doesn’t matter why!

  • Allison says:

    Great piece! I am always learning from this blog.

    What would the BM color of that first picture be? The blues seem to make the beige look greener or something. It’s picking a light neutral like that one (which I’m trying to do in my family room) that I find the most difficult. Dark colors seem to be easier to choose.

  • adunate says:

    Interesting, as always.

    My question is on ceilings. When painting a naturally dark room with a warm, dark color, what color should the ceiling be? A lighter shade of that dark color? Or a very light neutral?

  • Jennifer says:

    Love it…tell it like it is!! Great post Maria, couldn’t agree with you more! I love your big samples…so happy I bought them!!

  • This is a terrific post – I learned so much that I can use already. Now I know why the Edgewood Rock den looks a little green at night (artificial light sucks the warm out). I’ll be pinning one of the images, just so I can easily find the post again for reference,

    And this is why we all keep coming back to your amazing blog.

  • Amy Meinecke says:

    I had this problem when I painted my bedroom. I wanted a grey. I made a large swatch that looked fine. Painted the walls and the color was greenish at night. Changed the color and same problem. Instead of painting a third time, I changed the light bulbs to the Reveal bulbs and VOILA! The color looked great; no green!

  • Cathy Z says:

    Hi Maria,
    So I have a nit-picky question regarding that Crema Marfil job you mentioned. In that post you wrote “When we tried the Shaker Beige in there with just regular incandescent lighting, it was way too yellow, not right at all. Artificial light takes the warmth out of the colour and makes it cooler which was why the pink beige suddenly went yellow beige with the exact same marble.” I’m confused because I thought yellow is warmer than pink? So if you are taking the warmth out with regular bathroom bulbs – how do you end up with something more yellow than pink??

    I clearly am missing something but I can’t put my finger on it. Any clarification would be helpful.

    Also just want to say thanks again for your wonderful blog – it is my favorite one that I save for detailed scouring at the end after I’ve simply skimmed through all my others.

  • Cathy Z says:

    Sorry – my email was wrong in the above post! This is the right version 🙂

  • Sherry Daniele says:

    IT DID hurt my head (key word:’did’) until I participated in your True Color Expert workshop, and bought your large samples :> Now, I get through my color selections so much faster and painlessly!

  • christine says:

    Could you please do an article on colourists who can’t pick colours for their own houses? I know all about exposures etc.but CAN NOT find the right colour for my living room.This is professional suicide!!!

    • adunate says:

      I think it’s a woe common to all designers. I’m a graphic designer and it’s my job to create cool logos for others. Yet for years I’ve been trying to update my own and cannot. I feel your pain.

  • Heidi Nyline says:

    Hi Maria,
    So glad you quoted me because I really think it is easy to get hung up on what the right colour is supposed to be instead of getting the colour right. Large painted samples make it easy to see what the right colour is without needing years of education or learning about light and all the ways it affects colour.
    There are so many variables in every situation that it would be impossible to get the colour right every time based on just theory. You need to see a large enough amount of that paint colour on the wall to see if it is going to work or not. Big samples allow you to do that.
    Great post.

  • Thank god theory makes your head hurt. It kills mine! Lol. Same applies to fabrics in a room, don’t you think? I can see how some just come to life and even the prettiest things just die. Reading this blog is better than design school! 🙂

    • Thank you so much for this post well written 🙂 Picking paint color is always such a hard one for me. I am better sticking to fabrics but even with that you are right about bigger samples, it really helps! I do love a wall color that is camelion and changes through the day, I dont seem to tire of it so quickly.

  • In our previous house we painted our bedroom walls a creamy neutral to work in with aqua colours & stained wood. We had a high, very wide window over the bed that looked straight out onto our neighbours’ close-by orange tile roof, angled so that it caught the northern sun (here in Oz, that’s like your southern sun). Result, one ‘orange’ wall through most of the day. It looked ghastly. Curtains made the room too dark. My best solution was to not go in there during the day!

  • Kelly says:

    I don’t know what I did without my larger color samples. Like Heidi, when I put up a large color sample- it is large enough to see if it works or does not work. People just want the right colors selected and the larger samples show them just that!

  • carol says:

    that blue in the dining area is gorgeous

  • Marla says:

    I, too, really like that blue in the dining room! Am curious about your reaction, Maria, to the yellow/green cushions?

  • Maria Killam says:

    Hmmm. . . well what makes that dining room is obviously the windows and the chandelier. It would be just as beautiful without the kaleidoscope of cushions. They look like they’ve just been installed for fun!

  • Maria Killam says:

    Cathy, I forgot to answer your question. Red is the first and hottest colour in the colour wheel that is why its warmer than yellow. Maria

  • Great article and a great reminder about the importance of trying color on the wall first. I work a lot with fabric/drapes and curtains and can tell you the same holds true. Looking forward to exploring more of your articles.

  • Ginger says:

    Hi Maria!
    Please accept my apologies for having been a big lurker! Your blog was one of the first that I stumbled on to and continue to enjoy! You deliver incredible information with substance and style!

  • Gwen Yarbrough says:

    In reference to the pillows in the Dining Room…I believe that chose these accent pillows as a way to draw the eye to the large windows….It more or less frames these large windows without dominating the architectural features.


  • Kelli says:

    What is the name of the paint color in the dining room? It’s beautiful.

  • ‘Yes,’ I answered her last night;
    ‘No,’ this morning, sir I say,
    Colours seen by candle-light
    Will not look the same by day.

    Elizabeth Barrett Browning

  • Do you sell your large paint boards to BM dealers ? It would be great to be able to look at these samples in a store before picking a color or ordering the samples for personal use. Thanks for all your tried and true info on paint and decorating.

  • Jo says:

    Great article! It’s well worth the money to purchase sample quarts and make big sample boards, take them into the room/s different times of day, and see if the color works. Even if you spend $100 on samples it’s better than picking the right color that turns out to be the wrong color and then have to start over or live with it.

  • Jooles says:

    As a long time reader and fan of Maria’s blog resident in Australia I like to register a plea for clarity when discussing natural light.

    As I’m sure Maria is aware, in the Southern Hemisphere the effects of North and South light are reversed to what is experienced in the Northern Hemisphere. It may be helpful to some readers to specify this whenever discussing this topic. If it is clumsy to include it in the body of the text perhaps just a tag at bottom of blog telling readers to reverse North/South advice if they are South of the equator…?

    Which raises another factor in my mind… Are there any special considerations, natural-light-wise if you are resident between the tropics or close to the equator?

    • Maria Killam says:

      As I mentioned in this post, when you understand my system and use large samples, you can start to worry less about lighting and what it will do. Anytime someone has said “Maria, it went pink in the light” and I ask to see the colour, it was a pink beige to begin with.
      Hope that helps,

  • kelly says:

    Love this post. So glad you clarified that. I have been fighting the lighting in my home for years. I am learning so much from Blog and ebooks. I would love to be able to purchase ALL of your color boards right now, but since I cannot what would be the best one to get? Im a Home Decorating Enthusiast and considering the upcoming class in Boca Raton, FL. Can anyone say its worth it for an home decorator or should I just start with boards seeing how its not a business for me. Your thought would be helpful to me. Thanks!

  • Kali says:

    Maria – excellent post!

  • Chris says:

    Hi Maria, thank you for your post. I am in Australia and was looking for the right blue-grey to paint my kitchen island. This room faces west and every time I thought I had chosen the ‘right’ colour it always looked too ‘purple-ly’ in the afternoon. I changed it to one with a greener undertone and now I am very happy.

  • Melinda says:

    So happy to cross that worry off my list. I can share that we were VERY surprised when the new LED light bulb requirements in the USA made a big difference in our kitchen lighting. There was just TOO MUCH to learn to not hire a professional to help. 3500 lumens left a yellow cast over everything. 4000 lumens was a lovely bright white light. No one ever complained because a kitchen was too bright, did they? Well, they might as into the 5000 lumens, it’s hospital bright. So that MIGHT be too bright for some. It was too bright for us, so we settled on 4000 lumens. Our Killam approved colors hold up great in that light.

    • melinda says:

      oops… see why we hired a professional. It’s the KELVIN scale, (3500, 4000. 5000 +) not the lumens.

  • North Designer says:

    Hi there, enjoy the blog. Just wanted to let you know the link to the source (for your natural and artificial light info) doesn’t link correctly. Any chance you can send along the link or correct? I’m really interested in the lighting aspect and would like to read more from the source. thank you.

    • Maria Killam says:

      That designer is no longer in business, she retired, that’s why the link doesn’t work. Maria

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