Can't I just calibrate out a screen color shift?

[jon_vogel]

I stopped in to this forum because I am interested in playing with screen gain without buying a ton of screens or watching tiny swatches.

But I see a lot of discussion on finding the most neutral color.

My question is this: why do I care about a slight screen color shift if I am going to calibrate the system using a colorimeter? Can't you dial in a little compensation?

[prof55]

Yes, you can compensate. But so far, very little data has been collected on how far off the color can be and still be usable - plus, the amount of available adjustment differs between projectors. Because of this, the emphasis has been on starting with a reasonably correct color, then calibrating.

Now, if we could just get a handle on what "reasonably correct" is... :rolleyes:

Garry
ps Please post your data when you calibrate!

[wbassett]

I stopped in to this forum because I am interested in playing with screen gain without buying a ton of screens or watching tiny swatches.

But I see a lot of discussion on finding the most neutral color.

My question is this: why do I care about a slight screen color shift if I am going to calibrate the system using a colorimeter? Can't you dial in a little compensation?
Here is my 2 cents...

Yes, as Prof said you can compensate, but to a point. An example I personally experienced was for one gray I could not calibrate and adjust for the screen. All colors were off and not just a little. They were off enough that my wife would casually walk through the room and say "Something's not right." and walk out. She normally doesn't say anything so for her to notice and comment means it was very bad. With my current gray screen and any of the three white screens I had up she never said a word.

With that said, yes a screen color can make that much difference, but there are also variables, such as what Prof mentioned that some projectors can compensate for certain offsets better than others. Now since you want to experiment with gain, there are some very cheap and well balanced screens you can throw on the wall care free and cheap. So to answer your question, going with a color that introduces the least amount of shifting is the easiest, at least in my opinion.

Whites- Kilz2 and UPW are excellent white bases and very inexpensive. Rosco's Off Broadway White White is something very interesting to take a look at. It is slightly more expensive at $26 a gallon (That comes out to $6.5 a quart, but unfortunately you can't get it by the quart) and you'll have to order it, but it is a vinyl based paint in a matte finish that is very flexible and rugged. The reports are it out performs UPW hands down. Edited to note- Rosco has stated that this paint is actually widely used throughout the stage and theater communuty as screen paint and that is one of its recommended uses. Kilz2 is very inexpensive at $13 a gallon (That's what I have been paying for it) and Behr UPW tags in at around $12 a quart (in relative terms $36 a gallon).

Grays- For what you want to test and research, again I am going to recommend very simple and extremely well balanced OTS (Off The Shelf) colors. Winter Mountain is a Munsell N8 shade and can be bought at True Value for a low as $7 for a quart from what someone reported back. Gray Screen is a Sherwin Williams color that is also a Munsell N8 shade and provides excellent color reproduction. You can get the matte finish but it only comes in a gallon and is $42 a gallon. For what you want to do, you can use the flat finish which is around $11-12 a quart. Soothing White is a nice lighter gray in the Munsell N9 range, and again it is a Sherwin Williams paint that you can get in a flat finish for the same price as I just mentioned (around $12 for a quart)

Since you want to delve into gain testing, I agree you don't want to have to spend time color searching, and the colors I mentioned will get you a screen that you don't have to worry about color shifting. That should allow you to focus your energy on gain and texture. Your discoveries should be applicable then for any application method and a top coating shouldn't be dependant on color or method.

Resins are an interesting thing to look into, and there are some on here that have built some very high gain screens before. I am sure you already know that the higher the gain is the lower the viewing cone is. Some people don't like that trade off. I have a thread started, but dormant for just this topic and this would be perfect for in there.

One person that comes to mind that has had success making high gain screens is Bruce can. He would be an excellent person to start picking his brains and get some ideas from. Do a search on gain and some of his threads too and that should get you enough information to put with the ideas you already have...

This is the one topic I was hoping we would get into for 2007 so we're off to a good start early. :)

[bud16415]

Jon

Below in my signature is a thread I started doing just about what you are thinking of doing. At the time I started it I was aware of the color shift but also wanted the paint mix to be as easy as possible along with a gain improving feature. Both color and gain were on a sliding scale.

What I found in my case was this the simplest of gray paints can be made using white base and lampblack as a tint. There is a color push and these grays fall close to the 7500k color temp neutral. The screen I’m using is such a gray and the only correction I have made is to change my projectors color temp setting to 7500k.

That thread also contains the work that is now going on with trying to make a 6500k neutral gray and what pigments and ratios need to be added and in what rates.

The second part of that thread dealt with changing gain slightly by blending poly and paint together on a sliding scale. Feel free to join in on the experimentation and post to that thread your findings.