Where to start....or rather when will it end?
Originally Posted by narhic_fd
Thanks MM. Like you said I had some stuff right and some wrong. You cleared up a lot of stuff for me and helped me understand, better, the science of "WHITE" fusion. I thought that the part responsible for reflecting the light back off the underlying white surface, wither it be the gloss over/ or in the paint or the melamine in the TWH , was THE GLOSS. I thought the gloss was the "MIRROR". I though the gloss was responsible for shooting that light back to the top surface paint. But, If I'm reading you right, the main reason the light is bouncing was because of the "Opaque" or "nearly Opaque" of that underlying paint or as in the case of the grey underlying surface which would be silver metallic, like a mirror. Also, If I'm getting this right, when it comes to the TWH, its the Opaque of that TWH that's responsible for sending that "WHITE" attenuate light back to what ever top coat you have painted on the TWH. Am I getting you right on this??
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"..
Okay, concerning the TWH , If you are using the TWH as a stand alone "WHITE" fusion paintable board is the melamine acting as the "GAP" or do you still need to put some Plexiglas or spray a few coats of some transparent glaze over it?? If I want to try different combinations of paint on the TWH, in attempts to do a "WHITE" fusion do I need to put some kind of gap of the TWH first or as stated above is the melamine "THE GAP"???
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.
Second, how does the reflectivity of the underlying reflective surface, wither it be a mirror or I plain flat white as in the TWH effect how your top coat has to be when it comes to thickness of the application??Also, Lets say I use some plain, flat, white paint painted on the back of a piece of Plexiglass till it is Opaque then take another piece of plexiglass and paint a bunch of layers on it till it was Opaque, but with a white paint that had a higher reflection to it, because it had a lot of mica in it like one of the Liquitex white paints, or some high reflective white paint, how would that effect things as well??? Being more reflective does what to the equation??
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 !!!!!