How many layers of paint are needed to be sprayed on to make sure no light passes through

A member here named Tiddler did that test a few years back and painted on glass and recorded photos from the back side after each coat. If you search on his name you should be able to find the thread. Title was something like RS maxxmud experiments. The reason he did the tests was to try and figure out if there was any advantage to painting a mirror surface and if so how much. If I remember correct it was quite a few coats maybe 6 or 7.

You can use a 1/4" Nap Roller to paint the Rear of the Plexi with a Flat White Interior Enamel, "before" having primed it with at least one coat of Glidden Gripper (white). 3 Coats should be sufficient.

Personally, I do not feel using a Gloss White would be more beneficial than a Flat, only tend to collect and reflect light in a more narrowly defined direction....which is not what you really want.

But why not go full bore and use some Rustoleum or Dutch Boy Silver Metallic instead? The presence of a silver metallic underlay will not only provide a needed degree of light reflection, it also will help much more as far as improving Black levels and color dynamics than a white underlay alone would, the latter which is primarily a gain-retention method.

Personally, I do not feel using a Gloss White would be more beneficial than a Flat, only tend to collect and reflect light in a more narrowly defined direction....which is not what you really want.

The higher degree of reflection from the painted Plexi you get, the more thickness you need on the Top Coat to prevent pin-point light bleed though. "Mirror" Light Fusion requires the most care in that regard. Painted reflective surfaces less... Mirrors are the best only in the respect that they can create a more profuse "Glow" but in doing so, the degree of (thickness) paint on the Top Coat must achieve a almost perfect balance.

When you get down to painting the Top Coat via spraying over a painted , you should not need any more than 4 Duster Coats over either a Gloss White or Silver Metallic

One last suggestion, one that has it's roots in such efforts as done by CMRA. Consider (Duster) spraying white Gripper primer (2 light coats) onto the front surface of the Plexi before you start overlaying the Finish coats. When one was spraying a Gray Top Coat, having a initial "white" surface to accept the returning reflected light seemed to help collect and distribute the light with more effectiveness.

roller

Wow. I will compose your answer as soon as I compose myself. Let's just say you have a lot right...and a good deal of things wrong or at least mistaken.

Nuthin' that ain't "fixable", or stands in the way of success, but the things we / you have to get clear / correct are both essential basic to the premise of Light Fusion.

Now then...where is that Bottle Opener ?????

OK.

First off, I would still be suggesting TWH if it had a perfectly Flat finish. The fact that it has a Glossy finish holds no bearing other than it can make it more difficult for initial coats of paint to adhere.

This is because when "nearly Opaque" paint is applied directly to the surface of TWH, it essentially negates the Gloss factor, leaving only the "White" aspect to be of any consequence as far as affecting how bright the surface refection of the viewing surface will be.

References to "White" Fusion are made in such cases because of the similarities between what happened when absorbed light hits a White / Silver / Black underlying surface, and what occurs when there is a "Gap' involved as when a Mirror is employed for true "Light Fusion". In truth, the value as stated below are identical for use as a Top or Underlying reflective surface, just grossly lower in effectiveness in the "underlying" circumstance where a Translucent Top Coating of paint is in use, and applied so that some varying degree of light penetration occurs..

a. A solid, impenetrable White Surface will cease absorbing light, helping to maintain gain.

b. A solid, impenetrable Silver Surface will "slightly" attenuate certain aspects (frequency wavelengths) of light more than others, while also conserving the light of yet others. Blacks get Blacker...whites and colors still "PoP"

c. A solid, impenetrable Black Surface will absorb most all light it receives, attenuating Darker or Blacker elements proportionately more than brighter, lighter elements. Black is a "Gain Killer"

Now as far as what your trying to prove to yourself, everything depends upon the Translucency of your paint, and how well / effectively it is applied over the TWH. When using a Gray solution, you do want the surface paint to be just thin enough that some light penetrates and reacts to the underlying surface. If that surface is Glossy, the paint MUST be thicker, so proportionately, less overall effect will be available across the light spectrum. With a "1/8" Gap" involved using a "Second Surface" Mirror (original Light Fusion), it required that just the right amount of paint be applied to the surface to allow such penetration, yet also just enough to ****** the Mirror's tendency to broadcast a return reflection of the PJ's Lamp / Central point of illumination.

Experiments using 1st Surface Mirrors showed that the amount of surface paint had to not only be increased, the fine point between opacity and translucency was so small, trying to effectively obtain such was an exercise in frustration, if indeed not futility. Accomplished, and the result was spectacular. Anything else other than perfect meant either there was NO effectual advantage coming from the presence of a Mirror, or the Mirror itself was producing undesirable effects.

Sliding back to "White Fusion", a Glossy white underlying surface will require a bit more "surface" thickness to attenuate the glossy effect, yet the White element will still retain gain.
Gloss only makes things a bit more difficult under a 1st surface' use than a Flat white.

Now yes, to save time I have indeed used TWH "as is"...even for S-I-L-V-E-R as well as Silver Fire, primarily because a Glossy melamine surface will tend to have less surface irregularities. TWH was not a factor in the coining of the term ":White Fusion" That term was / is merely an expression of what happens when light penetrates a "almost opaque' surface and comes immediately in contact wit a bright, reflective surface. which in such cases is of course "white".

Ergo....less attenuation of light occurs than if the light was absorbed and lost.

Absolutely, if hand picking a sheet still does not produce a pristine, mar-less surface, applying a good primer will fix that. Smudges and surface spots can be reduced or eliminated using a Magic Eraser. Cleaning the surface is a good idea anyway, so as to make certain no grease or oil exists on the surface that would affect how the paint adheres or lays down.

Good read for anyone reading this thread.



http://www.avsforum.com/t/713810/rs-maxxmudd-experiments

Indisputably a good read, and a conspicuously good effort by the Author.

It certainly covers a lot of ground, and surely shows the validity of a Mix such as RS-MM LL when it's carefully "Roller" painted onto a White substrate.

But once the Mirror / Window experiments get started, much of it runs counter to what can and is to be expected when a Transparent or highly reflective (2nd Surface Mirror) surface receives a spraying instead of a rolling.

There is no way one can effectively roll on as even or as light a coating as one can spray using a well set up HVLP gun. And comments pertaining to how much light was penetrating at each applied level were relevant only to rolling.

But as previously noted, there is much info to be gleaned, and a careful and thorough read can allow one to pull all the right info forward.

I believe the OP was asking about rolling or a low cost sprayer. The technique of rolling a smooth uniform surface is not easy and takes a little practice. The technique of laying down paint with a sprayer might require a little more practice and the technique of laying down a precise layer of paint and controlling the thickness to obtain coverage but at the same time maintain the fine line between opacity and translucency and doing it to an optimum point and being uniform across 50 square feet of surface area using paint bases intended to be used to paint interior walls is going to have a long learning curve for a beginner DIYer, IMO.

Tiddler did his experiments based around the method and skills he felt most coming here could muster. I would love to see his experiments with glass and mirrors duplicated using spray techniques, done by someone that has the skills to maintain the degree of spraying control needed to get the results we often hear about. It would be quite simple to do during any screen painting to just have set up off to the side a window glass and dust on a coat with the same equipment and process used on the screen and then demo the results with a photo as he did. The thread also shows the A,B,C concept of comparing the results with color bars etc where the resulting image can then be tested to see if the overall CR has changed or it was simply a gain improvement that is reflected in the on and off axis photos.

We don’t really know if his experiments run counter to what could be expected due to rolling vs spraying because nothing as far as I know has ever been done to prove the spraying method in the same manner and degree of control he used.

Bud,

There is no way it would be sensible to suggest that a gradually applied Frosting of paint (duster coating) built up in layers could be equaled by any Roller on earth by any Painter, no matter how skilled and experienced. Tiddlers own "frosted" experiments showed the extreme difference (...and he used a can spray) in results, although that method did still leave much to be desired.

I certainly did not,nor would not fault his methodology...he has always been thorough to the extreme.

I have proved the LF concept over many personally done examples, a slew of direct comparisons, and via the many projects of AVS Members. Tiddler's effort was one based solely on proving or discounting both the LF effect (...the Frosting proved it...on the Mirrors...) but that same "frosting" method was not used on the Clear Glass examples....rolling was. Which rendered the effort essentially invalid as a comparison to what everyone else was doing "LF" wise. As a result, a few posters jumped in to state that his off-mark effort was definitive in it's depiction of how LF was an invalid concept. (not you)

Really though, that does go to show how even a well intentioned effort can be detrimental to people knowing the real story if even a small detail or process is changed. That is what has been so sad about several such efforts...things were simply not done as plainly specified...over and over again on the Threads.

Would that it had been different. But instead, the very act of pointing out such dependencies only opens up the opportunity for some to criticize the critiquing. And the "Critique-er"

I have painted Windows....for Rear Projection. It's also an exercise in precision painting...something no Roller Job can ever accomplish. Personally I would find it horribly redundant and a waste of my time to do such "testing" only to prove a point that needs no clarification except to those who want to discount the need for Spraying. I say; "Let 'em Roll away".

I have also rolled on SF/ BF apps onto Mirrors, using ultra Fine Nap rollers.....and that wasn't easy...at all. Certainly I did my best to make each coat as thin as possible...and to avoid leaving Roller marks at each application. 50% of the time, using every bit of skill and patience I could muster, still I had to "wash" the Mirror and start over. So no way I'll ever suggest such a method to anyone, let alone a NOOB.

In the end, and really all throughout the History of the "Spray vs Roll" debates, the primary reasons behind preferences between the two revolved around Cost, Mess, and Ability. Each of those concerns have been essentially eliminated...or in the least mitigated by the advent and availability of sub $100.00 Electric HVLP Guns that "ANYBODY" can use with just a little practice.

That is not a "IMO" statement...it's an absolute fact. And the ability to control the amount of paint going up...that is and has always been a distinct advantage that spraying has over rolling. Leastwise when putting up the "least" amount with every application is the goal. Yes...if someone either does not read the oft repeated direction provided on many different threads, or simply ignores them altogether, then their learning curve will indeed be steep...if not actually fraught with the peril of a long fall and a hard thump at the bottom of the hill.

Rolling a nearly perfect, streak free - mark free surface is a skill that most do not posses, nor will they succeed at doing so unless they practice the methods Tiddler outlined. That was, and is the one thing above all else he's contributed that has helped literally Thousands. Still, even with that, such efforts always involve using simple, Flat sheen-ed paints...paints already well known for their ability to cover both existing blemishes....and mistakes by the "Roller". To that effect, that is, and remains the only time such a method makes sense. Go beyond that to any paint more advanced than the RS-MM-LL that Tiddler rolled on and spraying then becomes the preferred...nay, the only viable option.

When paint is applied to a flat, impenetrable surface, there is NO Gap.

I gotta wait until later today to address all your Q's. Please be patient...I won't lose your Thread.

Where to start....or rather when will it end?

Whew. In the past, most all situations involved using a bright white "Flat" surface. Gloss surfaces came into play because substrates being considered had such. That required a slightly heavier, more opaque (...but still translucent...) coating to effectively squash undue reflectivity, yet still allow a benefit to be obtained from having a surface that would not allow light to penetrate / absorb further. In truth, either a Gloss or Flat surface will both "reclaim" light that has penetrated the layers of paint, and allow it to add brightness to the surface image that would otherwise be lost. It's the "Add" part that allows the concept to be considered a "Fusion" because the light did in fact pass through and exit the back of the paint, but in a 1st surface application, the distance it had to travel to / from the underlying white surface was almost negligible. Still, it does "rejoin" the painted layer, so therein lies the "Fusion"..

Forget the "Gap" in the"Paint only equation. For a "Gap" to be effective, it has to be at least 1/16" and that is a mile-wide distance compared to any amount of coating you might apply.

It's this way. A 1st surface application simply uses the under laying white surface as a retentive layer. If it's a bright Flat White under a White Surface, it will reduce / prevent loss of Gain. Flat White under Gray? Same thing again only a added boost toward lessening attenuation of whites.

Now if a piece of Plexi is used, and you paint the rear side with a flat "White Paint" until you cannot see "ANY" light passing through as viewed from the opposite side of the "PROJECTOR" light source, then Top Coat it with any paint, "THEN" you have true Light Fusion. But the degree of effect is really more dependent on how thin/ thick the Top Coat is, as relates to the PJ's own light output and the reflectivity of the under laying Plexi-Paint combo.

If a Gloss White instead of a Flat White is used as the "Rear of the Plexi Coating" then absolutely, the degree of reflectivity imparted to the "Gap" will be greater. But....if the Top Coat is not "thick enough", that reflectivity will be localized and result in a obvious Hot Spot. Using a Mirror increases that effect, but when corrected for by a properly applied coating, also increases the amount of light present "in the Gap" over a Bright White Flat or Gloss under coating. The degree of light in the Gap is what creates the famous "LF Glow", but as in all as described above...that only becomes optimal if the Top Coat is of a specific Thickness (...or closely adherent to a specific range...)

Most people who tried a dual coating (front & rear) on Plexi used a bright, Silver Metallic on the Rear, so as to combine both Reflectivity and Contrast enhancement. That was what we called "Super Deluxe"...a precursor to Mirrored Light Fusion. A Mirror was/is more effective in collecting and rebounding Light than was/is a Paint, and the Aluminum Coating that constitutes a Mirror provided the "Silver Effect" that at once both attenuated darker content yet reflected bright colors and whites more effectively than any painted coating ever could / can.

The latter was essential when one considered that the PJs employed "back in the day" only averaged 800 lumen output. Nowadays, with 2000 lumen being the norm, there is adequate light energy available to power through a Top Coat and use a less forgiving surface than a Mirror. And...with Mirrors over 4' x 8' being in short supply, the return to using a White or Silver coated underlay on a solid surface seems to fit the needs of more individuals. Also, the advent of Silver Fire helped to replace the loss of any advantages that a Mirror in the equation provided.

The times when that does not apply, and when using a Mirror is still optimal, is when a darker shade of Gray Top Coat is used. Such a coating allows for it to be applied thinner than one could a White Top Coat, and the increase in light reflected off the Mirror and sent back to re-Fuse" with the Top Coat also helps mitigate the loss of White levels that plague darker Gray surfaces.

There it all is. Act / react accordingly.

Now go do something......PLEASE !!!!!

That's "2" questions.

Yes, there is a difference. But also, consider that such brighter PJs only require Light Fusion if they also require (or the location does...) that the hue of Gray be exceedingly dark. When that happens, the darker paint serves as "additional layers" because it's increased opacity attenuates incoming light all the more.

With a "High Contrast, High Lumen PJ, the shade of Gray can be lighter, and the substrate a solid sheet.

When I want absolute maximum performance at a ridiculous level of room lighting, I don't send a Boy to do a Man's job. Silver Fire 5.0 / 6.0 and 2400 lumens Plus for a "normal" sized screen (110" - 120") up to 4000 lumen for 156"+

There is a limit to the number of layers, and it simply equates to a point where the effect of the PJ's Lamp Element and focused central beam stops showing as a distinct area. Through the annauls of SFLF creation, testing the surface image between the last 2-3 coats has always been essential. Used to be, people applied the paint much thicker. Things happened too. Runs...sags.....Orange Peel. Duster pretty much changed t5hat....but also increased the number of required coats from 3 - 4 average to 6 - 7 average.

But it's still remains a "look see" proposition with Mirrored Light Fusion, because if you go past a fairly abrupt point in paint thickness, the mirror loses it's effectiveness.

A White substrate is no different. You want the White to contribute to the overall effect. So the top coatingt must me ideal.

I can't put it better than that. n

I've been out of town, and besides...I needed to give myself a break from all your questions !!!!!!!



JKA.

....a little.

Your "one more" variety of question usually morphs into 3-4 combined.

The rear coating MUST not allow any further degree of absorption / loss. It should reflect as much light as possible, be it White, or Gray. The only way to be sure of that being the case is to apply enough paint so that you KNOW the surface is totally opaque.


BTW, I counted 4 questions.