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Discussion Starter · #1 ·

A few weeks back new member AH Theater offered to send me samples of some of Goo Systems product for a review and testing. It should be noted that AH Theater is the largest reseller of Goo products in the US. Three samples were sent.
  • CRT White Basecoat and Topcoat
  • Digital Grey Basecoat and Topcoat
  • Digital Grey Basecoat and Ultra Grey Topcoat

Since the samples were sent I upgraded my computers to Windows 7 which added a bit of a delay to the results. And while I am not completely done, I'm going to post what I have so far. I do not have the few photos that I've taken uploaded yet and I haven't finished gain readings either.

History​

From their brochure:
Goo Systems was formed in 2000 by an electronics expert, a paint engineer and a marketing professional. Our company consists of an electronics division, and a display technology division. Shortly after it’s inception, Goo Systems successfully launched Screen Goo into the market bringing a unique option for users to create their own projection screens. Screen Goo’s unique ability to be applied to almost any paint-able surface has seen the product being used in myriad applications.
Screen Goo is a specially formatted, highly reflective acrylic paint, designed specifically for the video projection industry. Screen Goo acrylic paint allows one to transform any smooth paintable surface into a high performance projection screen. Screen Goo's performance reflects many years of research and development. It has the capacity to outperform most of the existing screen products in use today. Screen Goo is made from the highest grade acrylic available and contains no filler materials. Whether used in a professional, or home situation it's simple application, versatility, quality and variable gain characteristics are remarkable.
Testing Method​

Spectrophotometer readings using a X-Rite i1Pro spectrophotmeter. There are two sets of readings. The first set is straight from the spectro utilizing it's own internal light source. The second set is comprised of grayscale and primary/secondary readings using my BenQ W5000 projector as a light source. The reference for the first readings is from an X-Rite Color Checker Photography card, the N5 value. This card is also utilized in gray balancing (I like to call it color balancing) the photo images. It is the most accurate way that I am able to get accurate color reproduction in a photograph. The reference in the second set of readings will be readings from the projector itself. Normally I like to use my Colormunki to get the grayscale readings. But as I noted above, I just installed Windows 7 and I hadn't had time to get it profiled with my i1pro yet.

Gain readings are done with a block of Magnesium Carbonate as a reference. The instrument used to get these results is a Sekonic L758C spot photometer. The gain readings will consist of just a simple on axis reading and then I'll attempt to find the half gain angle. From the small amount of time that I have looked at these samples I don't think there will be a viewing cone issue. They don't appear to have any gain at all. We'll find out Monday night.
 

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Discussion Starter · #2 ·
Spectro Readings Part 1

If you've been at the Shack long enough, you know that we rely pretty heavily on these spectrophotometer readings to interpret a screen's performance. And so far it has held true for most everything we've tested - the dnp supernova was one sample that threw the original reading for a loop. What we're looking for with this reading is D65. What is D65? D65 is the CIE Standard Illuminant that corresponds roughly to a mid-day sun in Western Europe / Northern Europe, hence it is also called a daylight illuminant. This is the illuminant that the Society of Motion Picture and Television Engineers (SMPTE) determined to be the standard. They go so far as to recommend the ambient lighting to be D65 as well as the color of the room. For our purposes though we are looking for a screen that is D65. Our determination behind this has come from the fact that if you have a projector that is calibrated to D65 and a screen that is D65, you will have an image that will be D65. so far this has held true in everything that we have tested outside of the Supernova, which utilizes a layered filter technology.

This first image is of our reference for the spectro numbers utilizing it's own internal light source. In the upper left corner is the CIE plot. A good sample, such as this X-Rite N5 Color Checker card, will plot dead center of this chart. Any push to the outside will constitute what we call a 'color push'. The further out the plot the further the push. On the upper right side is the spectrum chart. This is a very good example of what a true neutral spectrum looks like. For quite some time we believed (I should say we were led to believe by the folks at avs) that we were looking for a flat curve instead of this slightly bumpy curve. But after discussing this as well as other things with folks who have qualifications on the field, we found that the curve is as below. You can go and look at one for yourself at the Lindbloom Calculator if you wish. There are those, the Silver Fire crowd for instance, that believe the curve should be even more lumpy. That has been proven false within the Silver fire review which can be viewed here. The RGB Balance and the Thermometer charts are basically just visual fluff. They were included in my chart when I took this reading and I no longer use them. The numbers on the bottom left are the actual readings of the sample. 6504.4 is the color temp which is a few tenths high for D65. The L*a*b* values show this to be a true D65 N5 (for a description of the N or Munsell system - go here). The a and b values should be 0, which is pretty much where they are. And the L is the luminance value which shows 50 - ala N5. ;) The xyY values also show this to be D65 the values for D65 are x=0.3127, y=0.3290. The Y value is luminance.




This next chart is of the Goo CRT White Basecoat and Goo CRT Topcoat. The charts are moved a bit in these. The spectrum is now upper left, the CIE plot bottom left, the bulls eye chart replaces the visual fluff included above and the numbers are now on the bottom right. I've also added XYZ values for anyone who wants to go and plug these values into a calculator. CalMAN doesn't include anything for L*a*b* values, so there is only xyY. Remember we're looking for x=0.3127, y=0.3290. The other number included is the color temperature of the sample. D65 is 6504 or 6503.6 to be exact.

CRT White Basecoat and Topcoat



Digital Grey Basecoat and Topcoat



Digital Grey Basecoat and Ultra Grey Topcoat



Looking at this data, the CRT White sample looks fine. It has a slight blue/red push but it's very slight. Plus, white is by far the most forgiving screen color, at least paint-wise, out there. It is also one of the brighter, if not the brightest, white I have measured. I have seen better numbers from a Dulux White, but it wasn't my measurement. And that paint is unavailable to me.

Both of the gray samples have a more pronounced push towards blue. Both are over 500 points away from D65. Looking at these numbers would make one think "Why bother?" But there's more to this than just these readings. :bigsmile:
 

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Discussion Starter · #3 ·
Spectro Readings Part 2

These readings consist of a small portion of what a professional calibrator would be doing with your front projection system. Grayscale readings are similar to white balancing a photo in that if you get the gray readings correct, your color will be more accurate from the dark scenes to the lighter brighter scenes. Gamut readings consist of primary and secondary color readings. In addition to those 6 readings there is also two white readings to anchor the proper luminance for the primaries/secondaries. The primaries consist of red, green and blue. This is because these are the three types of cones in our eyes. Every color can be made from a combination of these three colors. Get one,two or all of these wrong and every color displayed by your projector will be off. Combine a screen that is way off to a projector that doesn't have a Color Management System, and you'd end up with a mess that only a professional calibrator such as umr or lcaillo could fix. And they may not be able to get it to where it should be, they may only be able to get it close. I could go into this more but there are many resources available to us that explain it far better than I do. Consult lcaillo's sticky in the display forum for some good pointers.

Grayscale Readings

The grayscale charts will consist of the actual data on top, a grayscale scatter chart in the middle left, the average color temp of the 10 IRE readings middle right, a color balance chart on the bottom left and a scaled RGB level tracking chart on the bottom right.
[PIE]
Even though there is an average color temperature on these charts, take it with a grain of salt. Since my meter doesn't do all that well on the lower end (0-20IRE), this number tends to be a bit skewed. Look at all the data and the numbers for a complete picture.[/PIE]

These readings are taken from 0-100IRE at 10IRE increments. Think of the Munsell system when I say IRE. A 0IRE image is black. A 50IRE image is similar to the N5 on my Color Checker card. Accurate grayscale means that you are well on your way to an accurate image.

To back up a bit, the data at the top displays both the measured value and the targeted value. The targeted value is denoted by a 'T' in front.

This first graph is of the readings taken directly from the projector.



The next graph is of the Goo CRT White Basecoat and Topcoat.



Digital Grey Basecoat and Topcoat



Digital Grey Basecoat and Ultra Grey Topcoat



The three Goo samples show the pretty much the same as they did in during the first spectro readings. The white appears to be OK with it leaning a bit on green. The greys carry out the slight blue push into these readings. These do appear to be somewhat slight but I'm not a certified calibrator... yet. I do believe that with a proper CMS system and a professional calibrator these things can be adjusted out.


Gamut Readings

As stated earlier, gamut readings are readings of the primaries (red, green and blue) and secondaries (cyan, magenta, and yellow). Also as stated earlier, if these are off, then all the colors will be off.

The first chart is directly from the projector. The top of the chart is again the measured and targeted values (targeted values are denoted with a 'T' in front of them such as Tx or Ty), bottom left contains the CIE plot and the bottom right has the DeltaE. The DeltaE is the error in the color measure. It has been said that a DeltaE of less than 10 should be the target. And that a DeltaE of less than 3 is close enough that your eye is incapable of perceiving the change. I cannot recall where I've read that or I'd have the link up. But it is what I've used. :huh: The 1994 refers to the formula used to determine the error. If you'd like to see the formula you can look at it here. I use the '94 formula because, well... CalMAN said that's what I should use. Never bothered to look it up but I'm sure someone brighter than I knows the reason. :T

Reference chart



CRT White Basecoat and Topcoat chart



Digital Grey Basecoat and Topcoat chart



Digital Grey Basecoat with Ultra Grey Topcoat chart



As you can see, all three samples submitted have DeltaE's around 3 or less. Which is good.
 

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Discussion Starter · #4 ·
Gain Readings and Photos

Gain

For Gain readings I use a L758C Photo Spotmeter, which will measure both fL and nits, and a windowed 100IRE image from the projector. The purpose for the Goo samples was to determine on-axis gain. I also did readings at ~70 degrees off axis to confirm my hunch that the Goo samples have no viewing cone.

CRT White Base and Topcoat

On axis - 1.0 gain
~70 degrees - .90 gain

Digital Grey Base and Topcoat

On axis - .70 gain
~70 degrees - .62 gain

Digital Grey Base with Ultra Grey Topcoat

On axis - .47 gain
~70 degrees - .43 gain

Photos

These are just some quick photos that I took of the three samples in front of my Elite EzFrame CineGrey screen. The dark upper left sample is the Digital Grey base with Ultra Grey top. The upper right is Digital Grey base and top. The bottom right is the CRT White base and top. The bottom left would be the X-Rite Color Checker card - N5 is in the middle. As you can see, pegboard hot spots! :rofl:





The photos were taken with my Olympus E-volt DSLR with the 14-45mm lens. The flash was off and everything else was set to auto. They were shot in RAW and then balanced using Adobe Photoshop and the X-Rite card. I cannot recall what IRE image is used but I'd guess around 60 and 80.

Looking at these photos you can see that the Digital Grey sample is pretty much the same as Elite's CineGrey. The Digital/Ultra sample is much darker. And the white is, well, white. ;) Stated gain for these three samples is 1.8 CRT White, 1.2 Digital Grey, .95 Ultra Grey. You can see from these photos that this clearly will not be the case when I measure them. My guess would be .5 to .6 for the Dig/Ult, .7 to .8 for the Dig, and around 1 for the CRT White. I can also say with a fair amount of confidence that these samples will have no viewing cone. They are paint, gray and white paint. There is no sheen to be seen and no reflective particles.
 

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Discussion Starter · #5 · (Edited)
Conclusions

It was great to finally get a look at the champion of professional paint mixes! Of the three samples, the only one I would think of recommending would be the CRT White sample. The two gray samples are not D65 to start with and I don't understand why in this day a professional company comprised of the knowledgeable fellows who started Goo cannot achieve this out of the gate. One of the founders runs an actual artist paint business and should understand the importance of color accuracy. Granted, in the day that they started their company, the projectors they were geared towards weren't exactly stellar. But nowadays the front projector that is 1080P with a full CMS is under $2000. And to slip within the 'good enough' mindset is no longer acceptable.

The biggest reason why Goo should be retooling their business though is recent events in the diy arena. Look at the extremely simple mixes that are available here at the Shack for less than a quarter of the cost of a complete Goo system. A 1000ml Goo system costs $230. That is way overpriced for what little value, if any, it will give you over an off the shelf quart of a neutral gray or white in a flat enamel. Granted you get the roller and flock tape with that but the Valspar, Behr, or even Sherwin Williams paint will come in much, much cheaper. For the price of Goo, there should be gold in it.

The CRT White performed fine but it's still way too expensive. And Goo needs to go back to the drawing board with the grays to get them to D65. Maybe consult with Liquitex on their Munsell grays. Theirs are neutral. Hopefully Goo will take this review to heart and in the future I'll be reviewing Goo part two! :T
 

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Nice work Mech....as always another one bites the dust....something us DIY'ers have known all along and have come to expect from ready made DIY products. Makes you wonder what BW in a can is worth if you package it with a roller and masking tape?
 

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Discussion Starter · #8 ·
I had higher hopes for Goo. They've been on the top of the market for some time and it appears that very little has gone into their R&D. There aren't many on the commercial paint mix side. There was one that Bill had received a sample of that he said was good. I can't recall if it was DIY Theater or Digital Image. There are a couple others that never submitted anything. And a couple more who I would never recommend - XFS Screens and Liquiscreen. The folks running those companies are a joke.
 

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Haha! Makes me even happier I went with a Shack DIY. The results are slightly alarming considering their rep and price... esp those greyer formulas.

You guys continue to blow me away with the dedication to the science..
 

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Something I didn't realize until today (when I ran the numbers) is that the Goo 'Ultra Grey' Mech tested is way darker than the Goo site (their gray scale chart) says it should be. Mech's sample was measured as being N7 while taking the RGB value of the Goo charts 'Ultra Grey' and converting it to get a Munsell N value comes to N7.8! That is too wide a variance to explain by lot-to-lot differences in pigments. Even using "low quality" house paints we don't find near that much variance. :dontknow:
 

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Wow, they picked the wrong guy to review their paint, lol. It looks like you did a lot of science for your review but did you actually watch any movies on the Goo, or take any screen shots? It's seems like it would only be fair to include those results too.
 

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Wow, they picked the wrong guy to review their paint, lol.
The thing is, we review all screens equally here. Our review and testing procedures are the same for all samples, both DIY and commercial; for our mixes and for others. As time goes by and we gather more and more testing equipment more tests are performed, but we always try to remain unbiased in our testing. Biased testing is worthless.

We have been accused of biased testing by a few others, those accusations are groundless. Peer-review is one of the reasons we publish test results and procedures. Those that have accused us of biased testing simply don't like what our tests have proven about their mixes. Rather than take the opportunity to better their mixes using the data from our testing (which is free) they cast stones and try to discredit us. That is their problem. We will compare our bona fides with theirs any day, others should as well.

It looks like you did a lot of science for your review but did you actually watch any movies on the Goo, or take any screen shots? It's seems like it would only be fair to include those results too.
The screen samples that were sent to Mech were too small to actually perform as a true screen, but were large enough to test.
 

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Discussion Starter · #13 ·
Wow, they picked the wrong guy to review their paint, lol. It looks like you did a lot of science for your review but did you actually watch any movies on the Goo, or take any screen shots? It's seems like it would only be fair to include those results too.
No. The sample that ZMan sent were the size of a sheet of paper - roughly 8X11. I don't think you can really watch anything on something that small. :T The things that really stand out are Goo's claims and the actual readings. Goo is really over hyped and over priced. Especially when it can be easily matched with a $12 quart of paint from the local store.
 

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Thanks for your reply. I'm surprised it didn't do better in your tests considering its high cost. Luckily I like the diy approach anyway so never ordered any goo.
 

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Discussion Starter · #16 ·
Did you guys ever get a responce from Goo Systems? I gather you forwarded the results?
No. The distributor who offered us the samples disappeared after this was published. I'm pretty sure Goo is aware of this review. :T To be honest, Goo's developer, given his background from avs, really isn't someone we'd want here at the Shack. I think he might rub the forum rules the wrong way, if you know what I mean. :whistling:
 
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