SMART is a process which will allow for the optimization and calibration of Home Theater Projectors using a low-cost "Do It Yourself" light meter and color analyzer. This introduction will attempt to introduce the principles behind the SMART process in layman’s terms. However, if knowing the intricacies of WHY SMART works isn’t on the top of your list of priorities and actually getting on with the calibration is, then you should skip on the other sections of this web-site. To read a briefer and somewhat more technical description of SMART, click here..

Color Mixing and Ratios
Say you are having another couple, Harry and Sally, over to watch a movie in your fantastic new Home Theater. You go over to your bar and pour yourself a White Russian, (for those who don’t know, a White Russian is an alcoholic beverage consisting of one part Vodka, One Part Cream and One Part Kahlua). You offer your friends a drink and, eying your white Russian, they say they would both like one. Harry says he would like a Big one, but Sally only wants a little bit, and since Harry has never been one to share, you decide to make Sally a tiny-tiny white Russian in a shot glass. So, as you are mixing you tell them that this is JUST like calibrating your new projector. They look at you funny, and wonder what piece of techno-babble you are going to spout next….

The SMART process is just like mixing drinks. Your projector mixes colors, instead of liquids, in the proper proportions to produce what is called a White Russian… No wait, I mean a D65 6500 Kelvin NTSC picture. The D65 flavor of Color mixing is also typically called "LOW". This is how your projector refers to it. The Projector mixes your visual color drink with combinations of Red, Blue and Green in the proper ratios to produce a visual "White Russian". Like you, your projector can make "White Russians" in different sizes depending on what your DVD player ordered. A Small "white Russian" like Sally’s has only a little bit of Red, Blue and Green in it, so when mixed together and poured on the screen the picture is black. A medium size one like yours has more of each color, so the picture is Gray. A large one like Harry’s (Don’t worry, Sally will drive him home) has just about as much red, green and blue as can be thrown on the screen, and so the picture looks White.

When you serve your friends their drinks, they are all drinking the same concoction – 1 part vodka, 1 part Kahlua, and one part cream. It doesn’t matter what size they are—they all taste the same. It is the same way with your projector, no matter what size it makes, it will still mix 1 part blue, with one part red, with one part green – if its doing its job right.

Now some might want their drinks a little sweeter (more Kahlua), or with a little more cream or with a little more bite (vodka). Color Temperature is a personal taste thing, and folks in Japan tend to use the "high" setting because they prefer more blue in their picture. Many people do not have their sets calibrated and will adjust their television’s controls until the "picture looks right" -- based on their personal preferences. Just like the recipe for a White Russian can also change from locale to locale. So why should I prefer the D65 Color Temperature (flavor)? Because that is what the technician doing your film transfers was drinking… If you want to see the movie as that technician thought you should, (who in theory is trying to preserve what the Movie Director wanted you to see), then you need a display that will show the movie just as transfer technician saw it while transferring it. He watched a D65 picture, so in theory, so should you.

Your projector’s low setting was "mixed" at the factory using the proportions for the D65 flavor of color. However, the factory probably did not ensure that your projector is really making the smallest and the largest White Russians possible.

SMART has Three Main goals:
1) Make sure your Projector makes White Russians in the right proportions at all sizes
2) To set your projector so that it can make the biggest video White Russian possible (brightest white)
3) To set up your projector to make the smallest possible video White Russian possible (darkest black)

The difference between the very Largest White Russian your Projector can make (brightest screen) and the Smallest White Russian it can make (darkest screen) is called Contrast. When a projector has more contrast, it has more of a choice of what size "White Russians" it can make and therefore the picture will look more Dynamic (more variation).

So far we have talked about mixing drinks of different sizes by combining the ingredients in an exact 1:1:1 proportions. We are using this analogy to understand how light, that you might say comes in Red Green and Blue bottles, can be mixed to produce black and white and all the shades of gray in between, as well as, yellow, orange, light blue, pink, etc. It's easy for a projector to make Red, just pour out of the Red bottle, just like anybody can make a drink that is pure vodka. Its getting the flavor right when things have to be blended or mixed that is difficult as now the exact proportions clearly influence the taste. It turns out that once your projector learns how to make white as an equal 1:1:1 mix, that the other colors will be right too. Gray is just white in smaller glasses and the goal of projector calibration is to get the right flavor of white no matter how big or small the glass. In projector talk the process is called gray scale linearity or grayscale tracking, but thinking about mixed drinks in different sized glasses is much easier

Unfortunately for us, the job of setting up to accurately mix color cocktails in the projector is a little more difficult than what goes on at your local pub. For one thing, Colors are a difficult thing to measure. You can’t just nip round your local grocery and pick up a couple of measuring cups to find out how much color you’ve got spilling onto your screen.

Before SMART, the only way to get an accurate calibration was to hire an ISF Certified technician to come to your house with a device that has be "calibrated" against a standard reference light source. In theory, wherever you take that device in the world, it will always measure color in accordance to that reference, just as carrying a Liter container anywhere in the world will allow you to accurately get a Liter of any liquid.
This device provides you with a Glass that you can use to measure equal "parts" of color for our White Russian, and it is what your manufacturer used to set the LOW color settings in your projector. However, due to the cost of these devices, most of us want a little cheaper solution.

This is where our photocell comes in. It will measure the amount of light incident upon the screen as a number of Ohms (the electrical unit of resistance). OHMS are inversely proportional to the intensity of the Light (Light = 1/ Ohms). This means the measured resistivity goes down when the intensity of Light goes UP and vice-versa. To measure the intensity of different colors, we simply have to put the appropriate colored filter in front of the photocell. This will prevent the other colors from reaching the photocell and registering in the measurement.
Sadly, the CdS photocell can’t be simply used to measure equal parts of Red, Blue and Green. This is because the photocell is more sensitive at certain wavelengths (colors) and less sensitive at others. This means when I measure a "White Russian" light source, with equal parts red, green and blue, my detector won’t read the same for all of them. It might read 126K½ for Blue, 52 K½ for Red and 60 K½ for green – even though we KNOW that are all displayed in EQUAL parts!

If we transfer this back to our "drinks" example, this presents us with a situation where we effectively have 3 graduated cylinders (remember chemistry class?) of different diameters with a scale that runs up the side of each. There is one graduated cylinder for each color that can ONLY be used with that color. (Pretend they blow up or something if you try pouring blue light into the red cylinder).

Because they have different diameters, when I pour colors intothem, they will rise to different levels, and therefore give different readings when we look at the graduated scale on the sides. The Scale on the side of our Blue cylinder says its measured in "Bleems", the red in "Rames" and the Green in "Grips" (these names are made up, but then, so is the example).

So in order to mix a new White Russian for our projector, we need to know how many "Rames" there are in a "Grip", how many "Grip"s there are in a "Bleem" and how many "Bleems" there are in a "Rame".

But we can find this out because our projector manufacturer sold us a pre-mixed White Russian cocktail with our projector – our projector’s low setting. And luckily, unlike a REAL White Russian, our colorized version is a LOT easier to break back into its former parts – we just place our colored filters in front of the photocell.

If we "fill up" each of the graduated cylinder’s using our pre-mixed White Russian (Low setting) we can see we have 50 "Bleems" of blue, 20 "Rames" of red and 30 "grips" of green.

Since we know the light coming from the projector is in equal "parts" we therefore know that 1 "part" = 50 "bleems" = 20 "rames" = 30 "grips".

With this information we have now "calibrated" our test apparatus (the photocell and the AVIA filters) To make our calibration MORE accurate in SMART, we will actually take a "set" of measurements, at different "White Russian" sizes and the Spreadsheet will average them together to get the most accurate calibration or "conversion" factors possible. Then all you have to do is write down your measurements in Ohms in the spaces provided. SMART will do all the work of converting them to Bleems, Rames, and Grips, calculating the conversion factors, and displaying results as an equal number of "parts".

(If you are interested in "doing the Math" to demonstrate how the spreadsheet does this unit conversion, please see appendix A)
So as a result of the calibration process, the SMART II spreadsheet will mathematically make 3 new graduated cylinders of EQUAL diameter, marked with the same scale and measured in "parts" to pour your measurements into. Because these new cylinders all have equal diameters and the same scale, if you pour a properly mixed "white Russian" into them, the colors will all rise to the same level. All you have to do to make sure you are mixing equal parts is make sure the amount in each cylinder is the same!

Measurement and Gain Adjustment
By changing the Gain in our projectors, we can change the amount of Red , Green and blue reaching the screen, and consequently the number of Rames, Grips and Bleems we measured and then converted to "parts" by SMART. When the projector mixes your drink, it pours equal amounts from each bottle of blue, green and red. The liquids pour from the bottle at different rates depending on how far over you tip the bottle while pouring. If your projector tips the bottle only a little bit, just a trickle goes into the glass. By tipping them a lot, a huge amount goes into the glass. You should think of Gain as determining the angle at which the projector holds the bottles while pouring the drinks, allowing it to pour more or less of a certain color in a given period of time. More gain for a particular color, means more of that color, less gain means less color.

How big of a "white Russian" we can make depends on the maximum amount of color that our particular projector can pour. For example, on the Sony VPL-VW10HT, the UHP bulb does not produce as much red as it does green and blue. Therefore, It can "pour" only so much red. Since we must keep the proportions the same, Red will limit how much Green or Blue you can add. In order to make the biggest White Russian you can make, you Max out the amount of Red you have and add blue and green to get the proper proportions.
Just as there is a limit to how big you can make your White Russian there is also a LIMIT to how SMALL you can make a "white Russian". The difference between the smallest size and the largest size determines the projector’s contrast.

Most projectors (except CRT based ones) have difficulty in cutting off the light from the bulb completely. Because of this, some light spills onto the screen even during absolutely black scenes. You still want this miniscule amount of light to be mixed in the same proportions as your "Biggest" white Russian. Otherwise the "black" that the projector produces will have "color cast" to it, and the black will appear slightly green, blue, red or any other color depending on how much the proportions are off. Most people also care how dark, the "black" of projector appears, especially with LCD projectors where the "black level" can be an issue. Fortunately the techniques described here will help improve the black level as well, but that's another subject.

Proper color balance is important across the entire spectrum from small to big, but especially at the highest light levels as the human eye is far more sensitive to colors at high light intensity levels. Your projector can output anything from a really, teeny, tiny white Russian in a Thimble, to a Huge one in a 5 gallon bucket. You must ensure it is capable of mixing each size in just the right proportions or the "flavor" will be wrong at that size. The Idea of gain adjustment is to make sure that, ideally, ALL of the "white Russians" your projector produces, from the smallest to the biggest, are mixed in the right proportions, and therefore have the right flavor of D65.

To see if your projector is doing this, we will sample the output from the projector at different sizes. These sizes will be measured in IRE. The Smallest size will be called 0 IRE and represents the black end of the scale. The Biggest size will be called 100 IRE and will represent the brightest while we can make. We can picture different sizes of glasses representing the different IRE levels, 0 to 100, with all glasses ideally having the same flavor. The smaller glasses appear darker because there is less of our "white" Russian.

IRE 0 to 100

In practice, we will "order up" these sizes using special video signals encoded on the AVIA DVD. We will then fill our photocell’s "graduated cylinders" from each size and feed that information into the Spreadsheet. The Spreadsheet will display our results at each size as "parts" in a graph called "Color Intensity". All you have to do is make sure that each color has the same number of "parts" at each level. An ideal response will yield three identical lines, red, green and blue, all very close in value. This means our projector is mixing our "white Russians " correctly across the entire size range. An example of this is shown in the chart below.

You might ask, if gain controls the proportion of color at all IRE levels, why do I need to make a whole series of measurements, wouldn't just one do? The answer is that if things were adjusted perfectly, that's all that would be needed, but there are several things that can go wrong and seeing that the light output for the three colors "track" each other properly is one important test of the projector's overall state of calibration. You might also notice that this curve is not a straight line because it corresponds to a "Gamma" curve of 2.2.

The curve is there because of the way real video signals "order up" different size "White Russians" for CRT displays. Suffice it to say, that as long as your curves correspond to a 2.2 gamma curve such as this one, the right sizes are being "ordered up".

Another view of the SAME information is obtained by looking at the ratio of the parts to one another. Since we should have 1 part red, one part green and one part blue. They are in a ratio of 1:1:1. So the relation of any color to any other color is always 1:1. The graph called "color balance" shows the relationship between the colors by their ratios. The graph shows Red parts to green parts (R/G), Blue Parts to Green Parts (B/G) and Blue parts to red parts (B/R). This graph is particularly useful for looking at how your "smaller" White Russians are working out.

As you can see in the above example, the values are close to 1 from 30-40 IRE up to IRE 100, but 0-20 are a bit off. This is quite common and because of the low light levels involved, is not much cause for concern. In an ideal response , all three lines would be near 1 at all values of IRE. However, this is very difficult to achieve.

Gain and Contrast
To make the biggest White Russian possible, you need the projector to tip those bottles over as far as possible to get the largest flow, and therefore the largest amount of liquid going into the glass. As we saw above, Gain tells the projector how far to tip the Red, Green and Blue bottles when mixing a drink, to get the right amounts into the glass, but the projector only has a certain amount of time to make each drink. To get the brightest picture possible you by raise the gains to as high a level as possible. This will make the difference between the brightest picture and the darkest picture even bigger, and therefore improve the projectors contrast.

Once the color balance is established using the gain settings, it is handy to also have a control that affects the overall level at which the projector produces color, but in this case, for a three colors at once. This is the user level control called "Contrast". Another name for the user control "contrast" is "White Level". We will use "White Level" to refer to this control to distinguish it from the concept of contrast – the difference between the brightest and darkest screen. When you raise the White Level, you are asking for the projector to tip ALL the bottles a little further, but to do it maintaining the proper proportions of 1:1:1. So when White Level is raised, the projector will tip the bottles more, more liquid will come out and the resultant White Russian will be larger.
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The gain settings and contrast are obviously highly interactive. If the combination of gains and contrast call for pouring more of any given color than the projector can handle, then the color balance (flavor) will be off with the larger glasses or higher IRE levels.
Essentially when this happens, one of the bottles the Projector is using to pour the White Russian becomes empty, while the other two bottles continue to flow.

One of the reasons that we run a series of IRE levels is that it allows SMART to detect whether one of the bottles is running empty. When it finds this condition, the best bet is to turn down the contrast, and not the gain for that color as that would also affect the color balance or flavor. (In practice it is necessary to adjust Contrast for different source components as their signal output voltages can vary and one needs to fine-tune the drive levels of the projector without messing up the color balance. This is the job of the Contrast control.)Brightness and Bias Adjustment

Ok, we have learned that gains and contrast settings control the level at which the projector pours colors as a function of the input signal or IRE level. Unfortunately, that's not the whole story. The problem is that liquids don't start pouring from the bottle until they have been tipped to a certain angle where the liquid just begins to flow out.

This is the overall job of the "brightness" setting, and, for the individual colors, the bias settings. Brightness can also be referred to as "Black level". You might say that the brightness setting tells the projector how far to tip the whole bottle rack before one can expect to get things started pouring. The Bias settings allow us to fine tune things for each color so that all of the bottles start pouring at the same time. Properly adjusted, this represents the minimum amount of blue, red or green that the projector can pour. Getting the bias and brightness levels right is therefore the key to a good black level and is how we get rid of any tendency for the black levels to appear colored or tinged with color.
If we set a bias point too low, no liquid will flow from the bottle into the glass, because the bottle hasn’t been tipped over far enough to begin the flow. So, in effect, if all of our bias points or brightness settings are too low, the projector starts serving up empty glasses, as the projector never tipped any of the Red, Green or Blue bottles enough to put any color in the glass at low input levels. An Empty glass basically represents the deepest black possible. Which is fine if we asked him for IRE 0. However, if we ask him for IRE 20 and he pours us an empty glass, that means the projector is displaying the same color black as he did at IRE 10 and IRE 0. We have lost all of that shadow detail!

Eventually, as we ask the Projector-Bartender for bigger and bigger drinks, he will tip the bottles more and more, until finally the glasses start to fill up. But until that point is reached, a lot of signal information is being lost in the black.

If we do just the opposite, and set bias points or brightness too high, the projector will be pouring more into the glasses earlier. SO if we ask him for a 0 IRE White Russian, he will in fact make a White Russian that is bigger than the smallest one he could make if he just lets the colors trickle out. The more he pours in, the brighter the color of black at IRE 0 and the worse the "black level".
The Size of the biggest White Russian we can make (the brightest image) hasn’t changed, so in effect the difference in size between the 0 IRE White Russian and the 100 IRE White Russian was reduced and we lost contrast!

This is why it is very important to have Bias levels set correctly. We do this simply by using our Photocell and measuring when our light output begins to change. First we lower our bias settings to 0 and then order a 0 IRE "black" Russian. Then using our colored filters we watch the measured light level for any change. The first sign of change means that liquid has just begun to trickle from the bottle into our glass. That is our bias point for that color, and also corresponds to the smallest amount of light we can produce for that color. In projector talk, this process is called determining the black point.Ideally, there would be NO light at IRE 0. Unfortunately, due to the way LCDs work, there is always a certain amount of "spillage", where light leaks around the "closed" LCD panel. It is as if, when starting to mix the drinks, there is already a little bit of "White Russian" that has already leaked into the glasses. This little bit of "leakage" represents the smallest White Russian the projector can make, and therefore the deepest black it can produce.

There is one complication here that needs mentioning. For every value of brightness, there will be different set of bias values necessary to determine the black point. Ideally it shouldn't matter what brightness value one uses in setting up the bias values. In practice, however, experience has shown that higher brightness values, with correspondingly lower bias values produce a somewhat better black level.

Different Sources
Different sources use different electronics to produce the video signal that is sent to your projector. These differences may result in slight variation in the signals sent. Your VCR, your Satellite Receiver, your old Interlaced DVD player, and your new Progressive one, may all mean something slightly different when they order up a small or a large "White Russian" For example, when your VCR comes up to the bar and asks for a "small", she holds her fingers so far apart to indicate that to your projector bartender. The Satellite receiver comes up and asks for the same thing, but he has bigger hands so his fingers are held a little further apart. They both want the same thing, a small white Russian. The same sort of thing can happen when ordering a "big" White Russian – their outstretched arms are simply not the same length. The Brightness and Contrast controls allow you to tell your projector what each customer means when they order a drink – ensuring that the projector-bartender will always server up the correct thing, regardless of who ordered it.

This means you can use the same color temperature for all components (This may either be one of the factory standard color temperatures, or ideally one determined using SMART. ) – all you have to do is change the Contrast/brightness settings.

AVIA comes with a nice, easy to use test patterns for setting the proper black and white levels. Unfortunately for other components, such as your source of TV programming, you will have to set brightness and contrast essentially by eye, using black in scenes and comparing it to black bars around the image. (Luckily you can produce black bars for most sources by simply changing the aspect ratio)
There is an added complication with brightness in that there are two fairly different standards on how DVD players, and other components make black. Progressive Players want to produce their blacks at 0 IRE, where most interlace sources (VCRs etc) want to use 7.5 IRE. So when a Progressive player wants to produce your darkest black, it sends a signal asking for 0 IRE. When your interlaced DVD asks for it, it sends a signal asking for 7.5 IRE. By setting brightness differently for these two sources, you can appease both, and always produce the darkest black available.

Color Correction Filters.
Remember how we said that the projectors black level was limited by light leakage? We lied. It turns out that there is a fairly simple way of reducing the leakage that is limiting our projectors black level - we just need to spill or waste some of the liquid going into the glasses. But we want to do this selectively and only waste some of the ingredients. We certainly don't want to waste any of the Red, as pouring Red is already the limiting factor at the higher IRE levels. But we can afford to waste some Green and Blue as their bottles have more volume in them than the Red bottle has . Before, we just turned down the Green and Blue gains in order to stay in balance with Red. So if we could find a way of wasting or spilling Green and Blue without wasting any Red, then we can pour more green and blue out to compensate for the waste and keep the right proportions or flavor. In this scheme, most all of the glasses will still be filled to exactly the same level with exactly the right flavor. We are just wasting some ingredients we had more of than we could previously use.

So how in reality can we preferentially loose some of the Green and Blue light, including the leakage light? The answer is a Color Correcting Filter placed in front of the projector lens! Just as our AVIA filters remove colors from our White Russian so we can measure them, a Color correction filter will do the same thing, but it won’t do it as completely. In theory, the AVIA filters remove all light but red, all light but green, and all light but blue from getting to the detector. For example, when we use the blue filter, NO red light and NO green light gets to the detector. A Color Correction filter is different in that it allows SOME of the other colors through.

So if I filter my White Russian D65 drink through a CC filter, it may remove some of the Vodka and Kahlua and leave the Cream unchanged. My drink just got creamier. The flavor changed! But we don’t want a flavor change, what we want is a smaller D65 White Russian!
So what we do is adjust the projector so that it outputs a different flavor than D65, and then strain it through a CC filter to produce D65 .
What happens when I try to make the Biggest White Russian using a CC filter?

Say we use a CC filter that removes 50% of the Green and 50% of the Blue from the projector's output. And let's say we want to make an IRE 100 white Russian. Red, which was our weakest output, produces say 100 part maximum at IRE 100. This means, with the filter off, the projector needs to output 100 parts of green and 100 parts of blue to produce a D65 flavor of white Russian on the screen. With the 50% filter on, the projector still produces 100 parts of Red because the ideal CC filter leaves red alone. However, the projector now needs to produce 200 parts of blue and 200 parts of green so that after the filter, the flavor or color balance is right. Luckily, the Lamp in the VPL-VW10HT produces way more Blue and Green than red, so we simply adjust the gain so it produces these amounts.

So what have we accomplished by wasting some of the Green and Blue if we haven't changed color balance and most of the glasses are filled to exactly the same level with the same flavor white Russian? Lets look in the very smallest glass…. normally it has just that amount of liquid that "leaked" around the LCD panels. But by adding a CC filter, 50% of the green and 50% of the blue leakage will be removed! There is actually less liquid in the smallest glass because we have managed to spill or waste the leakage colors! We now can produce a very small white Russian, which in projector talk is a significantly darker black level.

OK, If you have been following this carefully, you might be saying to yourself, "Wait a minute, we just removed some of the leakage from the Green and Blue bottles, but we still have all of the leakage from the Red bottle reaching the glasses. Doesn't this mess up the taste in the smaller glasses?!?." The answer is your right, this process lowers the Green and Blue levels at IRE 0, but not the Red. To understand why this works in practice we need to understand a bit more about color perception by the human eye.

We have already mentioned that the eye is less sensitive to colors at lower light levels, and therefore color balance is not as important as the lower IRE levels. The next issue is that the eye perceives luminosity or light intensity principally by how much green is in the light. Therefore the better we do with maximizing the Green contrast by keeping green leakage out of the small glasses while still properly filling the big glasses, the more the eye will perceive this as improved contrast. At lower light levels, the eye becomes quite insensitive to Red, with the eyes maximum sensitivity shifting even more towards blue when the eye is completely dark adapted. So the reason that the CC filter tweak works to improve the black levels without perceptible changes in the color balance, is that the tweak takes advantage of the way we see and interpret colors at the lowest light levels. Because of the way your eye works, the perceived improvement in black level will be EVEN BETTER than what our "electronic" photocell detector will tell us.

The other thing worth noting is that we have dramatically changed the flavor of the White Russian our projector produces (in the above example, the flavor produced is now 1:2:2, not 1:1:1)! This means that the output from the projector without the filter is going to look wrong ! So always leave the filter ON when using a color temperature designed for use with the filter.

Over-Correction
However, just like Red, there ARE limits on how much Green and Blue are produced by the UHP bulb. If, in trying to use a CC filter you choose one that filters too much green or blue or both, then the Blue or Green limits are reached, and we begin to lose brightness with the filter on (But not contrast – the blacks get darker at the same rate the whites do.)

In the original example, Red determined the "Greatest Equal Part." However, in over-correction this changes. Say that in the above example our projector produces a maximum of 100 parts of red, 200 parts of green and 175 parts of blue. When using our 50% filter, we MUST have 200 parts of blue to maintain a D65 flavor (temp) and the same brightness on the other side of the filter. However, since we can’t get 200 parts of blue, just 175, Blue has just determined the "New Greatest Equal Part".

On the projector the proper recipe is 1 : 2: 2 of red, green and blue

So if we need twice as much blue as red, and our maximum is 175 parts, then red must be set at 87.5 and Green set at 175.

As you can see, the overall size of the "biggest" white Russian is now smaller. (Red, Green and Blue are all set lower than when 100 parts of Red was used as the "Greatest Equal Part"). Over correction is therefore very similar to adding a slight Neutral Density filter to you projector as well as a CC filter, as the light intensity of all three colors is somewhat diminished.

Luckily, the blacks also got blacker by the same amount. This is called over-correction. It does NOT Lower contrast, and it’s a matter of personal preference if you want to over-correct or not. Generally you over correct if darker blacks are more important to you than overall image brightness.

Closing Remarks
Hopefully this little drink-mixing lesson was helpful in understanding your projector and the SMART process. However, some generalizations were made, so here are a few parting remarks:
The Proper recipe for D65 is NOT 1 part red, 1 part blue and 1 part green. For all intents and purposes this doesn’t matter because your filters let through varying proportions of the other colors and the Photocell doesn’t measure them 1:1:1 either so the real proportions for D65 and the Proportional sensitivity of your detector (photocells and filters) get put collectively into the same conversion factors.

By normalizing the whole mess to 1:1:1, it
A) makes the whole thing a LOT easier to understand
B) Doesn’t change the results.

The filters included with AVIA don’t really filter all of the red, blue and green. This means that when we measure each color, we will always be a little high, since some amount of light from the other colors gets through and registers on the photocell. So in reality, the calibration run and the conversion factors computed for it are for the photocell and the particular filters we are using. .

The Bleem, the Grip and the Rame are friendlier names for
Blue/½, green/½ and Red/½ respectively. (The ½ sign, and worse, the 1/½ can be a little scary to some, so I hid them.)

If you still didn’t understand a word of the above discussion, don’t worry. The rest of this document will tell you just what to do and when to do it, and you don’t really have to know why you are doing it.
Good luck and Bottoms Up!