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Studio light setup?

I watched Marks videos on setting up studio lighting for painting and am trying to come up with a better lighting system for my studio.  My wife won't let me install anything permanently, so I'm trying to come up with something that I can attach to a homemade easel.

Has anyone tried something like these LED work lights?  They are 5000K color temperature and produce about 5000 lumens.  I can locate them about 9 feet high.  I'll probable mount them side by side about 1 1/2 feet apart and I figure I can re-aim them for even coverage.

What'cha think?

AmazonSmile: LED Flood Light Outdoor 2 Pack - GLORIOUS-LITE 50W LED Work Light - 5000LM Bright Outdoor Floodlights with Plug, 5000K Daylight White, IP66 Waterproof Outdoor Lights for Backyard, Garage, Garden, Lawn: Home Improvement
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Comments

  • mstrick96

    On the assumption the lights are 5 feet from your easel, this will produce about 200 lumens at the painting surface and about 100 lumens on the palette.  Aim for 800 to 1000 lumens on the canvas and palette.

    Denis

  • CBGCBG -
    edited March 29
    dencal said:
    mstrick96

    On the assumption the lights are 5 feet from your easel, this will produce about 200 lumens at the painting surface and about 100 lumens on the palette.  Aim for 800 to 1000 lumens on the canvas and palette.

    Denis


    That lamp looks somewhat directional (although 120 degrees is quite like a spot light... ), so of the 5000 lumens, more might be falling on his canvas than from a non directional source... yes? no?

    I'm curious about the 200 lumens at 5 feet.  :)

    Also, should we be talking about Lux (lumens/unit area) rather than lumens?


  • Thanks all!  Very helpful!  I like that light that KingstonFineArt recommended!

    These lights seem to randomly specify either Lux or Lumens.  The lights I found specify total Lumens which then has to be converted to Lux at a given distance.  I wasn't completely clear on it, but I was planning to use two of them to give a total of 10,000 Lumens.  I like the light that KingstonFineArt recommended better though!

    And Dencal, thanks for the Lux recommendation at the canvas and palette.  That helps!

    I found a page with several lighting calculators that look very helpful.  Lumens to lux (lx) conversion calculator (rapidtables.com)
    CBG
  • Hmm... now the conundrum is how to light your finished work with the same brightness, temp, and evenness as your studio lights... so it looks right

    :)

  • CBG

    That lamp looks somewhat directional (although 120 degrees is quite like a spot light... ), so of the 5000 lumens, more might be falling on his canvas than from a non directional source... yes? no?

    I'm curious about the 200 lumens at 5 feet.  

    Also, should we be talking about Lux (lumens/unit area) rather than lumens?

    I found it to be more accurate to accept the mfrs rating for their designed fixture rather than assuming the lumen level to be calculated on a spherical dispersion

    The 200 lumens at 5 feet is based on the inverse square rate of light fall off from the source.
    At 5 foot only 4% hits the canvas (5 squared is 25 and 25 into 100 is 4. 4% of 5000 is 200).

    Yes. Lux (light level per unit area) would be a better unit of measure but for our purposes is an unnecessary complication.

    Denis
    CBG
  • I've ordered one similar to the one the KingstonFineArt recommended.  The only difference is that the on I ordered has barn doors on it.  I may not use them, but I though they might be handy.

    And CBG, I'll put up with that problem!  Right now I'm use a desk lamp, and an Ott light as well as a floor lamp to try to light me paintings!  This HAS to be an improvement!!! LOL

    CBG
  • @mstrick96

    Good on you!!  I love the lights these folks are suggesting for the studio.. they look awesome!  I'd want 2 to light the canvas and two nifty stands to go with 'em (maybe a third for the palette and heck a 4rth for the still life box once I make one...)


    As for the conundrum, I'm not sure about how one is to light a painting on a wall without: 1) uneven brightness across the work, 2) expensive installation into the ceiling or a lot of clutter involved in a stand or bracket or arm for the light  and 3) stray distracting bright light hitting the wall just outside the frame.   The wife loves white / off-white walls... and hates any clutter so, I guess I'll just mount them on the outside of the house, or keep em in the studio (when I have one).  

    Come to think of it, maybe there is another thread on this forum I should be looking at/posting too... 
  • I received the light today.  I got the one the KingstonFineArt recommended, but I got the version with the barn doors.  I like it a lot!  Here's a quick review of my impressions so far.

    The size and weight are great. It will be easy to mount to my homemade easel.  (I made an easel similar to the one Mark give the instructions for, except that I added some t-tracks to give me adjustability.) 

    I also think I'll like the fate that I can adjust the color temperature and the fact that I can dim both the warm and the cool temperatures.  This will allow me to see what the painting looks like under different lighting conditions and perhaps help to avoid the "CBG Conundrum"!  LOL 

    The barn doors fold up nice and flat and are not bothersome.  My thinking is that they will help prevent the light from lighting up the area behind me.  

    The light comes with a removable white diffusion filter.  With the filter in place, I measure 200 Lux at about 1 meter.  With it removed, I measure 350 Lux at one meter.  This is with an exposure metering app on my iPhone.  The manufacturer specifies 3360 Lux/m on the Amazon website so I can't reconcile their specs with my readings.  I'm going to write to the company to find out what their specs mean.  I was interpreting it as Lux at 1 meter.  The readings I'm getting seem to correlate to Dencal's calculations.

    If the readings I am getting with my iPhone are correct, this means that I will need 3 to 4 times as much light to meet the recommendation that Dencal gave earlier of 800 to 1000 Lux at the canvas surface.  I don't think my eyes will be able to handle that much.  My eyes are very light sensitive.  I'll need to try it in use though to find out How I react to this much light.  Right now it feels like a lot of light.

    Thanks for all the help!  Experimenting with this light is going to help me figure out exactly what I need.  

    Here's the unit I got:

    AmazonSmile : Neewer Professional Metal Bi-Color LED Video Light for Studio, YouTube, Product Photography, Video Shooting, Durable Metal Frame, Dimmable 660 Beads, with U Bracket and Barndoor, 3200-5600K, CRI 96+ : Camera & Photo




    CBG
  • @mstrick96

    They borked their units.  "Lumen 3360Lux/m" makes no sense.

    Maybe it was a problem with a non technical person doing the translating (from a Chinese manufacturing company).

    They should be quoting total Lumens (Lum) (coming from the whole panel) or quoting lumens of the panel per unit area (which you could express in Lux = lumens/m^2)
    since the panel is actually a flat area, the second option is not so ridiculous.


    Sent a message to the company, let's see if they respond.
  • I sent a message to them right after I posted this.  We'll see what they say.  

    There are a lot of problems like this on Amazon with their descriptions.

    I'm about to rig up a mount for the light to attach it to my easel.  
  • May I complicate this discussion to the ridiculous?  

    My (beginner) paintings look pretty ok from a standpoint of realism and color value. However... when I bring them into the house, they look excessively dark. So I’ve been doing some amateur color studies in my studio using white paint on blocks in the light box and looking at them with my color checker. 

    The color checker holds the white paint at a 45 degree angle to the studio lights, which are 5000k and relatively bright compared to the subject. So when I match white to white on a 45 degree block in the box, I have to add brown (quite a lot) to tone down the super bright version of white on the bright studio side, which is why my paintings are tilting dark. 

    If I hold the color checker vertically, instead of 45 degrees, the color is much closer but still brighter because of the disparity in lumens. 

    Also, a vertical white block in the box looks much darker than the angled block which is facing more toward the light. 

    I understand now why the checker is at 45 degrees because it will give you an average tonal reference on the studio side between white that is tilted toward the light and white on a vertical surface. (I’m factoring out shadows of course — only pure light.)

    Having said all that, the colors seem to be truer in my painting if I use a vertical color checker because of the brightness of the studio. 

    My next move is to rip out the 5000k studio florescent fixture and replace it with a dimmable fixture. Then I’m going to match the temperature of the studio lights to the box, and make them all dimmable to see if I can get an acceptably moody subject in a studio bright enough to work in. Ideally, I’ll use the same bulbs for both. 

    This color matching business, with lighting thrown into the mix is complicated. I think the optimal solution might be to light the subject with the studio lights off, and then adjust the studio lights to match a 45% block with the 45% checker. I think that’s Mark’s solution. But I’m also going to use a vertical color checker because the painting is vertical and that’s the orientation I care about. 

    Any thoughts on this are welcome. I’ve read a lot about lighting studios but precise language is so important with these technical discussions and a lot of the advice I’ve read leaves me in a fog.  

    The primary issue for still life painting I think is the disparity in light between the subject and studio. I don’t see a lot of info on that out there. 

    Ciao!

  • edited April 2
    Mark Carder says multiple times in different videos that painters complain their paintings are too dark when on display in regular homes.  I think you have hit the nail on the head, regarding why that is so. He values deliberately painting for museum/gallery illumination, instead of normal home lighting environs.  
  • @ken

    I think the primary issue is the difference between the lighting in the studio and the lighting of your artwork in the home.


    If your color checker is in the same light as your canvas, and the angle of your color checker is the same (or relatively the same) as your easel, then the value of paint on your color checker will look exactly the same as on your canvas.  Alternatively, you could also arrange your studio light to make the same angle "away from perpendicular" with your color checker as your easel.  [For example, if your easel was straight up and down and your color checker was at 45 degrees, a studio lights at 22.5 degrees downward from the horizontal would have the same angle of incidence on both surfaces, assuming also that the light is evenly spread left to right so to speak (you do color check off to the side relative to your canvas).]  

    In such a case the difference between the lighting on your canvas and the lighting on your subject does not matter, as long as you can match what you are seeing coming from the subject, your painting as lit should more or less have the same colors/values as the subject.

    If you change the lighting on your final painting, for example once finished, it will not look the same, although arguably the "relative" values and colors in that lighting should be right.  Arguably, the relative values/colors are all you can shoot for, if you have no choice as to how to light your final work, and since lighting of still life's is an arbitrary and relative thing, it likely does not matter too much, as long as your final work is well lit enough for a viewer to see what they need to.



    If you wanted to attempt to capture a still life at absolute values you could try to work backwards from your brightest final lighting using a digital camera in manual mode as light measuring device.

    However, that process might not improve your final work, because the level of light necessary or ideal for the process of painting might far exceed the level of light necessary to view a painting. In fact your work might suffer from inadequate lighting of the subject/canvas during the painting process.



    Mark's general implication that everything should be very well lit (canvas, color checker, palette, and final work), is probably the best advice.





  • What I'm hearing I think is confusion with the isolation of still life lighting and the lighting on the canvas. Also that the painting looks different in different light conditions. Home lighting is still pretty warm light. Your studio light is probably around 5200°K. Much cooler that home lighting. Which should actually enhance the look of your painting in home lighting. 

    Back to the isolation of still life and painting light. The 'window' to the still life is just like using a photo. It can have any color balance within it's frame. All you have to do is match what's in that window. You can trust your eye and test a color mix on your canvas. Or… you can put a dab of color on a piece of card and go right into the still life and see if it matches. Or… you can paint a dab of paint on the object in the still life. Or… use a color checker. 

    Being invested in your color palette and knowing how to make color quickly and economically takes some time to learn. Knowing that pretty much all color come from the 3 primaries of red, blue and yellow. And of course how that all works is at the center of the artist toolkit. Another thing to start thinking about is that color and value are one in the same.  Let's say we make a mix of Cobalt Blue and Cad Red Light at value 5 or light value. Value being measured on a 5 or 7 value scale plus black and white. It's color/value.




  • Interesting discussion.  Since I paint only from photographs or from the computer screen I'm concerned about the light falling on the canvas.  

    I used my "redneck engineering" and cobbled together a mount for my new LED light.  I'm pleased with the brightness which is 2 1/2 to 3 times as bright as what I had before.  I also was able to set up my old fluorescent desk lamp to light my palette so that it is lit at about the same brightness. 

    I'm getting around 300 Lux at my canvas.  I might want to add another one of these lights.  

    I can already see that having more light is going to help my painting a lot!  

    I got a reply from Neewer asking for my Amazon order number, so should get a response from them tomorrow about my question on the specification units.  I'll post whatever I get.  
  • @mstrick96
    Be careful too much light is worse than too little.
  • @mstrick96 I too thought my paintings were too dark at home until I saw them hanging in a gallery.  Homes are generally not lit very bright.  And then on another occasion I saw one of my paintings at a museum but they didn’t have very good lighting and the painting did look a bit dark but the relative values and colors were still good.  A lot depends on the gallery lighting.
    Dustin_Cropsboy
  • We have collected art for many years and I had the same discussion with the director of a local museum about light color etc. He said most oil paintings look best at 3700k but are usually painted at 5200k. Consequently if you want to see a painting as the artist did, light with 5200k lighting. That’s what I have in our house and that’s why I lit my studio at 5200k. 

    So... I brought some of my favorite paintings out to my studio today to see what they look like on the easel. And they don’t look great. I don’t know why except that it may be the fluorescent tubes in my light. They are supposed to be 5200k but the pictures look dull. The walls and ceiling are painted black so I have zero glare except from the overhead lighting. Oddly, the light looks better and I get less glare when I take the refracting cover off and expose the bulbs. Counterintuitive. 

    I think it’s worth the effort to replace the fixture with a dimmable 5200k LED so I can adjust the light on the easel such that good art (not mine!) looks optimal and then paint in that light. 

    Once the studio lights are adjusted similar to a gallery, I’ll leave those alone and only use the dimmer on my shadow box as a variable. 

    Mr Kingston’s advice that too much light is not good rings true as well. My first light setup blew out colors so much that I could only see glare on the canvas and every color looked the same on my palate. 

    Thank you for the advice folks. I’ll keep you posted. 

    Warm regards


  • @ken
    It's only really been a few years that artificial light has been really measurable on °K or rated with CRI indexing. Even most professional photographers didn't have color temperature meters. CRI numbers weren't printed on light bulb packages.
    Natural light in a studio can fluctuate  dramaticly over the day. Outdoor Plein Aire can vary wildly from wildly also.
    40 years ago I learned this °K color system as a youngish art director. I worked with a lot of photographers and film people. The color film stock of the day was balanced by batch numbers to the Kelvin scale. You would have to adjust you color filter pack to the batch. You didn't do a shoot with film from different batch numbers. Photo studio lighting set ups were measured for the °K if they could afford the meter.
    I didn't hear about it again until the last few years when we were forced to start using greenish pigtail fluorescent bulbs. 
    Then LEDs come on the scene with horrible cold light. In the past 3 to 4 years CRI numbers are publish on most packaging and LEDs have come up with schemes to make good adjustable lights cheaply.

    But it all comes down to knowing color on your glass. Your palette. How to mix color value and temperature. Black walls and precise lighting are no guarantee of good expression of color. Only the intimate knowledge of the mixing of color will do that for you. Practice. Practice. Practice. 

    I painted from 1968 to 2003 using a 2 bulb fluorescent drafting lamp I bought when I went to school. I bulb was cool the other was warm. I still use that lamp today with the same 52 year old bulbs on my drawing table for watercolors.
    ken
  • LED’s and flourescents both go on and off with the ac current so there is a high-speed flicker that plays into the equation. Filament bulbs have the same ac issue, but the heated filament doesn’t change temp fast enough to cause a flicker. 

    I painted last night under the bare fluorescent and I think it is an improvement over having the diffuser on the fixture. 

    Thanks again for the advice. It’s been very helpful. 
  • @KingstonFineArt I think I might have the same style lamp!  Is this it?

    When I graduated from High School in 1964 my girfriend's (now my wife) parents gave me this desklamp since they knew I was starting college at Ga Tech.  One cool, one warm bulb and I'm still using those same bulbs!  

    I had been using it plus an Ott light and a lamp with three LED bulbs to light my easel.  I had it lit from three sides.  I'm now using it to light my acrylic palette.  




  • @KingstonFineArt @CBG @ken
    Correct me if I’m wrong but it seems that the key tho g when painting from life is to make sure the light that falls on your canvas and on your color checker when you are checking colors and values in the shadow box is the same.
    it doesn’t matter what light you have in the shadow box.  
    The only other thing is how much light lumens you want to have on the canvas.  780 lumens is the recommended amount.  
    If you go lower, say 500 then your paintings would look better in a darker gallery?

  •  I was at two galleries yesterday and should have taken Lux measurement but I didn't think about it.  I'll be back up there on Wednesday and will take some readings.  I was at the Booth Western Art Museum which is one of the top galleries in the country for Western Art.  They also operate a gallery (The Downtown Gallery) for members of their Art Guild.  I have two paintings in the Downtown Gallery.

    In my case, I don't think my eyes will allow me to use much more than I have now.  I am measuring about 300 Lux at my canvas.   My eyes are pretty light sensitive.

    Another thing I've noticed is that the 5000K side of my new Neewer light is too harsh for me. Hurts my eyes.  What is most comfortable for me is to mix the 3100K into the light.  Right now I'm running both at 100%.  

    I was also at my art lesson Thursday night and noticed that at first the light level seems rather low because I had gotten used to the new light level in my studio.  I also notice that as the evening went on, I seemed to adapt to it.  

    I'm seriously considering taking Mark's "Carder Art Academy".  Maybe that will help.
  • All this talk of lux and lumens it making me blind. 
    Just enough light. Never too much. I have a cataract in one eye and don’t see well. I run my light at 50%. 
    This light thing seems to be a procrastination. 
    dazle
  • CBGCBG -
    edited April 4
    GTO said:
    @KingstonFineArt @CBG @ken
    Correct me if I’m wrong but it seems that the key tho g when painting from life is to make sure the light that falls on your canvas and on your color checker when you are checking colors and values in the shadow box is the same.
    it doesn’t matter what light you have in the shadow box.  
    Mostly agree. 

    But the light in your shadow box should be "in the range" of your paint. 

    IF your shadowbox light is way too bright (relative to your studio), you will not be able to capture those very bright colors and values using color checking... your paint only has the capacity to reflect your studio lighting.  Conversely, IF your studio lighting is way too bright relative to your shadowbox light, you wont be able to color check the real darks with your paint... as your paint will be overlit.

    GTO said:
    @KingstonFineArt @CBG @ken
    The only other thing is how much light lumens you want to have on the canvas.  780 lumens is the recommended amount.  
    I tend to agree with @KingstonFineArt, just enough light... i.e. you are the creator who needs to see and reproduce the still life, and being able to see everything of importance in the subject and confirm you are doing it properly on the canvas is really where it's at.

    GTO said:
    @KingstonFineArt @CBG @ken

    If you go lower, say 500 then your paintings would look better in a darker gallery?
    Studio lighting is another story... I think once you light the still life so you can see everything you want to see and see it well, and once you light your studio so that you can reproduce that still life properly and confirm that... well then all you need to do is light your finished work up to the level required to reveal all those important things in the work.  

    I would not suggest changing your painting process to take into account the studio, but instead demand the studio support your work.



  • I would say that more people don't use a self contained light box in painting still life. They may have a space separated by a simple curtain. Or no separation at all. Their painting light is lighting the subject. This goes for figure painting as well. I can't remember ever having well controlled light while figure drawing or painting. A lot of my still life stuff is just a piece of fruit sitting on my workbench with a lamp hovering over head. With the aid of a rheostat I can easily control the brightness. Add a sheet of tracing paper to defuse the lamplight and you got a painting. I ignore the imperfections.
    I built a multipurpose 'cage' and shadowbox this year to control the light better. It works great. But it's just simple common sense. I would never make the shadowbox too bright. It doesn't make sense.

    I don't use a color checker. Never did. I think Mark says that it's a tool to start understanding color mixing. So setting up your studio to use a checker is probably not a good goal for the long term.

    If you paint or sketch outside you'll not be working in the best conditions. The light changes every 5 minutes. The intensity, angle and temperature are never the same. Ever changing. Probably a good training ground to help appreciate your inadequately lit studio.
  • Thanks @CBG and @KingstonFineArt those are all good points on lighting.  
  • I use a painting knife the way Mark uses his color checker.  If I'm painting from a photo, I try to laminate it or put it in a plastic sleeve so that I can place the paint over the photo for comparison.  In any case, I can't  tell what it looks like until I actually put it on the painting surface!

    I've started using watercolors for plein air and I don't particularly worry about getting the color perfect.  I figure if it's good enough for horseshoes and hand-grenades, it's good enough!!!  Maybe, once I get better, I'll try to reproduce exactly what I see in the field!  

    The other thing I've done is to start using Mark's color palette for almost everything!  I particularly enjoy  mixing "tube colors" from just the primaries plus white!!
  • mstrick96 said:

    Maybe, once I get better, I'll try to reproduce exactly what I see in the field!  

    The other thing I've done is to start using Mark's color palette for almost everything!  I particularly enjoy  mixing "tube colors" from just the primaries plus white!!
    Maybe you'll learn that reproducing exactly what you see isn't all that important.

    Mark doesn't own the idea of mixing color from the primaries. It's been the way of color for over 150 years since tubed colors were made available. It became an industry. Calling the primaries a limited palette is about the only thing I split from Mark with.
  • @KingstonFineArt
    I have a friend in Missouri, Doug Hall, who uses the three primaries plus white exclusively.  He says he owns a tube of burnt sienna, but only rarely uses it.  Also John Pototschnik uses it a lot and James Gurney uses it at times.  It seems that the vast majority of tube paints are convenience colors because I can mix almost all that I've tried.

    I can mix any color I can see with the primary palette, but sometimes am pretty slow.  Only the high chroma purples and turquoises are out of reach, but I've found that I usually grey those down anyway.

    I'm experimenting with making my own paints from pigment and oil.  I like the slow-dry medium recipe that Mark gives.  If I'm going to make my own paint, the primary palette is a good way to go.
  • CBGCBG -
    edited April 5
    @KingstonFineArt and @mstrick96

    I'm a novice and still trying to figure out the terminology, for what is what.

    A. The colors you need to arrive at and finally paint on your canvas.  Unless you have purchased a paint by number kit, you never have those colors, you make them for each work.

    B. The colors you start with, they come out as they are from a tube, you mix, using whatever process, to get those colors on your brush you need, namely, A.  Depending on the process, the colors one starts with could habitually always be the same for any work, but they should be versatile enough to enable any necessary adjustment to a color.

    In a typical process usually daubs of B. are placed on the palette to access them in generating A., and then often (for efficiency) one generates daubs of A. from B. in appreciable amounts particularly for colors which are cover a significant portion of the work.


    Of the above A. and/or B. what exactly constitutes "the palette" of colors?

    Of A. and B. (or even some subset) what exactly constitutes "primary" colors?

    What is a "primary palette"?

  • @mstrick96

    This is my mixing palette. A 12 color spectrum with dual primaries palette.
    This is the extreme of working from the primaries, The bottom row are the primaries, secondaries and tertiaries. I mix and tube the secondaries and tertiaries from the primaries. I takes 3 or 4 hours once or twice a year. I do this because this structure allows me to find and chromatic neutral in a few minutes or even seconds. The three dual primaries work to control temperature. 
    This seems extreme. It is the logical extension of primary color mixing. There are relationships between primaries that make the secondaries, primaries and secondaries that make tertiary colors. And between the secondary and tertiary that make chromatic or 'semi neutral' color. 

    When I look around at the world around me the color I see is chromatic neutral with occasional spots of bright color. Even the bright color has spots of neutrality. I called it managing grays for most of my life. 

    Much of my color mixing could be achieved using earth color with primary and secondary color. But the painting wouldn't have the same chromatic harmony that this base structure provides. This is foundation color. It's economical to make color. Fast, accurate and cheap. It's foundation because it's a good place for an artist to modify their palette structure.





    I carry more colors on my palette. Neutralizers; Yellow ochre, Rembrandt Transparent Red Oxide ( a good substitute for raw umber) and Burnt Sienna. On the bottom; White the great neutralizer, semi neutral blue ( Blue Green + Blue Violet), semi neutral Yellow ( Yellow Green + Yellow Orange) and semi neutral Red ( Red Orange + Red Violet). If you notice the semi neutral colors are mixes from tertiary colors. It's a color proportion thing. There's more often than not some Veridian and Vermillion on there too. Call them adjunct color. 




    I don't just start painting from this. I first find my basic color 'recipes'. The 'big palette' is used to simply feed and tint the recipe mixes. An incredibly fast process. So for a 8 hour a year commitment to mix and tube I get speed, economy and chromatic harmony in return.

    This is not the only way I use color. I use earth color balanced palettes when doing wet watercolor and Gouache. Admittedly not as much as in the past. 


    This looks like a lot of work. For some it may be I'll give you that. But there's no math unless you want math. John Sloan's book; John Sloan on Drawing and Painting from Dover Books on Amazon. He lays out this structure starting a page 116. This is a great book all the way through. 


  • Back to the original topic, I finally got a reply from Neewer on what their specification units mean.  

    "Lumens: 3360 Lux/m" means 3360 Lux per square meter at 1 meter distance.  They called that "illuminance"  

    KingstonFineArt
  • Every 'Made in China' company has a different language for their products. The question is does it work for you?
  • Absolutely!  I love it!  I have my light set up to be balanced between the warm and cool light.  Right now, I have it set to 100%, but I think I'll probably turn it lower.  I was at the Booth Museum today and measured the light levels there. They were at about 100 Lux or less, plus I noticed that they are balanced between warm and cool.   My light is producing about twice that!  I'll play with adjusting it until I get a comfortable illuminance and temperature.

    Like you said, we need "just enough" light.  
  • @mstrick96 help me out.... how many lumens is 100 lux. ?    What I have is four 1500 lumen bulbs at a three foot distance from the canvas. I figure 666 lumens on the canvas.   1500 x 4 = 6000.   6000 * (1/sqrt (3^2) = 666
    I think that equation is correct.

  • Here's a calculator for converting lumens to lux.  I comes pretty close to your calculation.  It got 571 lux

    Lumens to lux (lx) conversion calculator (rapidtables.com)

    We need to know how the total Lumens are measured.  It seems that there isn't a lot of engineering rigor in presenting specifications once "marketing" gets involved.  Some seem to present to total light output of the bulb in all directions, while others present total lumens per unit area.  If it is presented as per unit area, the specifications needs to be at a specified distance.  

    In the case of the Booth Museum, their ceilings are about 14 feet high and they are using halogen spotlights in the ceiling aimed from different directions.  to illuminate the artwork.

    One thing about museum lighting is that it is deliberately kept low, because light degrades the paint over time.  So "museum lighting" is not very bright, but has a well balanced spectrum and the illumination is very even.  Most homes don't have dedicated lighting for their art.
        
    I had never really thought about "how much" light is needed by the artist.  Interesting discussion.

    CBG
  • CBGCBG -
    edited April 8
    GTO said:
    @mstrick96 help me out.... how many lumens is 100 lux. ?    What I have is four 1500 lumen bulbs at a three foot distance from the canvas. I figure 666 lumens on the canvas.   1500 x 4 = 6000.   6000 * (1/sqrt (3^2) = 666
    I think that equation is correct.

    Q: How many lumens is 100 lux?  Answer: anything. 

    1 Lux = 1 lumen per square meter.  If I told you I had illuminated a piece of toast at 100 lux, you would know exactly how many lumens per unit area was falling on the toast, i.e. in the same way you could be told how "thickly" it was buttered.  But knowing the total lumens falling on that toast requires a knowledge of how big that piece of toast is... the brightness of the illumination (Lux) does not change with the size of the toast but the total amount of light (Lumens) falling on the toast does.  A piece of toast the size of your kitchen will take much more butter to butter at the same "thickness" all across it, than a normal piece of toast, even when the amount per square inch is the same everywhere.


    The meaning of the terms should be kept in mind when you see them being bandied about.

    When speaking of a canvas surface, lumens as a unit is generally inapplicable.  300 lumens "at" a canvas... is meaningless... if all 300 lumens are falling on a 1inchx1inch canvas that will be over 1000 times brighter illumination than if 300 lumens fall on a 3 foot by 3 foot canvas.  Lumens per square area, e.g. Lux are the units which are relevant.  Canvas sizes are completely arbitrary (unlike toast which is relatively standardized).  

    As @mstrick96 points out, for light bulbs, figuring things out depends on the specs provided for them.  You can characterize a bulb based on the total number of lumens given off, combined with a loose description of the angular distribution of the light, or as @mstrick96 mentions, in Lux (lumens per unit area), at some distance, more than likely in a direction of a sweet spot (for example directly along a perpendicular of an LED panel).


    As for your specific question/calculation, you could try to determine how much of that 6000 lumens actually falls on your canvas, or you could determine the Lux level at your canvas. 

    Both depend on directionality of light coming from the fixture... four lights on the end of poles sitting in space, would spread all that light generally over a sphere, but if they are mounted on a plank or in a box, and you essentially have reflectors (painted white or silver or lined with foil), this could be more closer to a hemisphere or even better a generally directed beam (say 2/3 of a hemisphere, or a third of a sphere)

    If you have reflectors and all 6000 are going into e.g. a third of a sphere solid angle, you will have about 1700 Lux illumination at 3 feet distance (as @mstrick96 calculated, with no reflectors you get 571 Lux at that distance).


    If you want to know total lumens on your canvas you have to multiply Lux by surface area (in meters squared), but that number is not particularly useful, as explained above.

    Hope this helps to clear this up.

    PS:  Specs either in Lumens or Lux are perfectly useful to get a relative idea of how much illumination you need.  IF at 15 feet, you find your 100 lumen bulb is not enough, and you find it does just fine at say 3 feet, then you know  because light drops off with the square of distance that you need a 2500 lumen bulb (or twenty five 100 lumen bulbs, or five 500 lumen bulbs) to get that ideal brightness at 15 feet.

  • Good explanation @CBG.  

    I have an app on my phone that gives me a reading in Lux, but it is mostly useful to make relative comparisons.  What I've learned is that with my new Neewer light set up 5 feet from my canvas gives me a reading of about 200 Lux and the reading at the canvas of the paintings at the Booth Museum is about half that and the paintings are perfectly illuminated.

    One experiment is worth 1000 calculations!
    CBG
  • Thanks @CBG and @mstrick96.  I see how the lux value has to do with the angle and surface area.
  • @CBG Here is my explanation of a "palette" of colors.

    First of all, the "palette" is the surface that you use to mix your colors on.  It can be anything.  Plastic, glass, wood, a paper plate.  You've seen the traditional oval shaped palette that artists used to use.  What I use is the Masterson resealable palettes.  I use either a sheet of glass in it, or acrylic or sometimes palette paper.  It's just what you mix your colors on.

    Next. the "palette" is the set of colors that you use to mix the colors you use in your painting.  If you mix color strings the way Mark teaches, these would be included in the definition of "palette".  

    You probably already know this, but the "primary" colors are the set of colors that cannot be mixed from any other colors.  However, the primaries can be used to max any color found in nature.  For pigments, these are red, yellow and blue.  These are the colors that Mark uses.   This is what I am calling a "primary palette".  I like the Geneva colors of Pyrrole Red, Cadmium Yellow Light, and Ultramarine Blue.  Mark used to use Alizarin Crimson for his red.  What seems to work best is a red that has a little blue in it.  

    A white is always added to the primary palette for lightening your mixes.  From these four colors you can mix almost every color you can see.  Your color printer uses the paper as the white and then three primaries and also a black for darkening.

    From there, you can add other colors to make mixing faster.  Mark adds Burnt umber, but that can be mixed from the three primaries.  There are only a few tube colors that can't be mixed from these colors.  


    CBG
  • Greetings,

    As planned, I installed an LED fixture to replace my old fluorescent. The new light is 5500 lumens compared to 4800 and has 5 temperature settings and is controlled by a dimmer. 

    In a nutshell, the 5000k setting matches the color of the light in the shadow box, and at roughly 90% brightness, the painting looks good and I can see color gradations that were invisible before and the palate is finally sharp. 

    The light was $100 at Lowe’s, the rheostat was $35. success at last!

    I have monkey’d with lights for so long, the glass of wine I’m painting now has mold on it. “Vanitas still life with molded wine”


  • @ken

    Mmmm. That full bodied and old earthy taste only a proper molded wine can provide.

    Can't wait to see it!

  • @mstrick96
    As I have shown I work and make my palette from my chosen primaries.
    Your statement There are only a few tube colors that can't be mixed from these colors. Rings untrue.
    If you change your primary red select to to Quinacridone Red all of your red influence colors become very different than using say Pyrrole Red. If you change all the primary choices your entire palette is unique. All derivative colors are unique to the primary parents. I can think oft colors only palette that you can't mix from the palette you describe. Alizarin Crimson and Viridian. Two very magic colors. You can make chromatic versions of some earth colors but they are not the same.
    @ken
    What is the SKU of the light from Lowe's

  • @mstrick96
    As I have shown I work and make my palette from my chosen primaries.
    Your statement There are only a few tube colors that can't be mixed from these colors. Rings untrue.
    If you change your primary red select to to Quinacridone Red all of your red influence colors become very different than using say Pyrrole Red. If you change all the primary choices your entire palette is unique. All derivative colors are unique to the primary parents. I can think oft colors only palette that you can't mix from the palette you describe. Alizarin Crimson and Viridian. Two very magic colors. You can make chromatic versions of some earth colors but they are not the same.
    @ken
    What is the SKU of the light from Lowe's

    @KingstonFineArt

    Are you alluding to the idea that any one primary palette, although capable of mixing a great many colors would have a unique color gamut different from from any other primary palette?  Hence some colors of one palette will be outside of the gamut of the other palette, i.e. the different perimeters of the gamuts have consequences for colors near those perimeters.

    or Are you saying there are some gaps within the color gamut spanned by the colors of the primary palette which you cannot mix?






  • @CBG
    To answer your question.Yes!
    When you have one primary red to mix from or 1 set of primaries you are limiting yourself to that 'harmony'. Which is a good thing.

    You're displaying here digital color gamuts. A completely different animal than color pigment gamuts based on a single set of primaries. As are offset printing gamuts completely different. If you've ever tried to match a painting to an EPSON large format printer on a specific paper you know it's not a simple task. Even from a high end scan. Gamut is a huge issue for some key colors. Pigment in watercolor, gouache, acrylic and oils don't always really play well in digital color. This is a separate large issue of discussion.
    I worked in all realms of color and color reproduction for 50 years from letterpress to the Bloomberg terminal. I've  made thousands of prints on my Epson 7800 on dozens of paper types. 


  • @KingstonFineArt

    I suspect that if one were to map out the color gamut of a primary palette (say 5 colors) there would be a finite continuous color gamut covered by all the combinations, but its shape would be very different from anything like those produced with RGB or CMYK. 

    That said, one can imagine taking one primary color and mapping out mixing that one color with a second (and closest) primary color at all possible rations.  That line would be identifiable and continuous... continuing the process with other nearest neighbor primaries you should be able to produce the entire perimeter for the gamut.  Once complete it is clear if one mixed more than two colors at a time, one could presumably cover all the colors within that gamut... the clor vectors might not be in straight lines, but it should cover all the space inside.



  • The light is Allen-Roth (Lowe’s private label) #2592471.

    I recommend it for anyone whose spouse will allow it. 

    Sorry, had to make that joke. 
    KingstonFineArt
  • @ken
    Thanks I'm going to look Ito this for my shop.
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