CGIV For mech

[benven]

Hi guys, nice job on the Black Widow. Since mech was curious about CGIV, I'm gonna spill the beans. I was waiting for the gain testing to be completed but it looks like there is alot of other work that needs to be done. This is not an ambient light buster. It is a nice compromise between a white screen and a darker gray screen. I have been into darker gray screens. All of the previous CG mixes were pretty much around an N6-7. Actually, they also used a latex based aluminum product However, my taste has changed and I like a brighter, whiter screen all around. As mech has previously tested, CGIV is about an N9 shade. It's more complicated than the Black Widow, but the materials are pretty much readily available.

Here is what I mixed up.

Base coat:

240 mL Varathane Outdoor Satin Polyurethane
240 ml Behr Ultra Outdoor Flat White no 4850
20 mL of H2O, plain tap water
2 mL of Pearl Ex Silver Powder no 663

Main Mix:

420 mL Varathane Outdoor Satin Polyurethane
240 mL Behr Outdoor Flat Deep Base no 4300
240 mL Behr Ultra Outdoor Flat White no 4850
40 mL of H2O, plain tap water
8 mL of Pearl Ex Silver Powder no 663
50 mL of Pearl Ex Micro Pearl Powder no 650

Top Coat:
400 mL Valspar Clear Protector no 64675
160 mL Behr WOP no 751
160 mL of H2O, plain tap water
2 mL of Pearl Ex Silver Powder no 663

You don't have to use the base coat. You can paint the main mix right over top of a white base. The main coat is translucent so I wanted a bit darker gray shade, so I made up a gray base. You don't have to use the top coat. It does give you a bit more gain and better blacks. Like most topcoats! I have yet to topcoat my screen. I am debating whether the on axis benefits outway the off axis benefits. As with most pearl topcoats, they look yellowish off axis and obviously with the gain they provide, a little darker off axis. But blacks are better. What to do, what to do......

As you can readily see, I have used products that are made for the great outdoors. That means no yellowing over time if exposed to UV. That also means you can use this on an outdoor screen. The other good thing is, if you want a lighter or darker gray, simply adjust the amount of silver powder. Edited: Forgot to add this in my original post.

mech tested the main mix as being neutral, or really close to neutral. Warning, he has not tested the topcoat because I haven't sent him a sample. However, I don't see any issues with it based on my testing. Please see attached gray scale file. Don't worry about the top end. That is my projector. I can't get into the service menu anymore and I had tuned down red gain, the only change I had to make in the service menu, with my previous screen. A minor adjustment of red gain and gray scale would be really good. Only user menu adjustments were made. Measurements were taken about 6" from my screen, at a 45 degree angle, with an Eye One and HCFR software. The pearl topcoat measurements were taken off of a test panel placed in front of my main screen.

[mechman]

And I am still waiting for my block of Magnesium carbonate!

When it does show I'll get it done.

mech

[muzz]

Good to see ya Ben.

Looks promising, as usual!!

Keep up the good work

m

[cynical2]

Awesome, Ben!!

Thanks for posting. A few questions come immediately to mind:

• Any screenshots comparing to a comparable shade of grey?
• What tool do you use to correctly dose the small quantities (like 2mL)? Syringe?
• Some already know this (since PFG's benefits are now documented), but would you be interested in a brief comparison to CG-III? Pros/cons, etc?
• Would you consider also "spilling the beans" on any of your previous latex Aluminum based mixes? For instance, would you share what aluminum ingredient you used?

Anyway, I'm excited that you're willing to share CGIV with us...and do not at all intend on pushing you beyond your level of comfort, but you've been experimenting a long time. The more that new folks can learn from folks like you and Bill and mech, the better off the DIY community will be. It's also great to see the gathering and posting of REAL DATA.

And for all to know...I paid for the magnesium block on Jan 3rd...I just emailed the company to see what the issue is, but hopefully mech will have it in-hand soon. Sorry mech!

[benven]

Hi Jim.

I don't have any comparison shots. Just plain lazy I am.
I used small little 1 mL spoons that I purchased with the pearl powders. I was using my wife's kitchen measuring spoons but she quickly put an end to that.
Compared to CGIII, this has less gain. Therefore, larger cone. Better blacks. Whites aren't bad comapred to CGIII. I don't see that dingy yellow off axis colour like I did with CGIII.
The beans on the latex aluminum product, Createx Auto Air Aluminum Fine, I used have already been spilled. Check out the AVS archives for the original CG, dark like a Firehawk, and CG Plus. Unofficially, CG Plus was leading the pack in an ambient light shootout that never happened.

[cynical2]

benven wrote:

Hi Jim.

I don't have any comparison shots. Just plain lazy I am.
I used small little 1 mL spoons that I purchased with the pearl powders. I was using my wife's kitchen measuring spoons but she quickly put an end to that.
Compared to CGIII, this has less gain. Therefore, larger cone. Better blacks. Whites aren't bad comapred to CGIII. I don't see that dingy yellow off axis colour like I did with CGIII.
The beans on the latex aluminum product, Createx Auto Air Aluminum Fine, I used have already been spilled. Check out the AVS archives for the original CG, dark like a Firehawk, and CG Plus. Unofficially, CG Plus was leading the pack in an ambient light shootout that never happened.

Thanks, Ben. A shootout that never happened...sounds strangely like a sig I recall seeing.

[mechman]

Hey Ben,

I put this under the microscope and there are red and blue flecks(?) in it. Do you know what causes this? Is it the Pearl powder? With my eye I can see nothing but what appears to be a N9 with a little bit of sparkle to it.



mech

[benven]

Ha. You saw that too. I also see red. It's funny, when the mix is wet and I hold it under a halogen light, no other light gives the effect, I see RGB specks. It must be the pearl flakes acting like little prisms? I can also see this when dry, but not to the same degree. The good thing is no sparklies when viewing.

[mechman]

Here's the magnifications...





How did you get the mica to not act like a prism? No color shifting little prisms like I've seen in all the others. Does it have to do with the quality?

mech

[benven]

Very odd. Maybe quality of the pearl and silver powders has something to do with this. I have no idea where the read and blue spots are coming from. The mix is translucent. But I did paint the base with white paint, Behr 4850, prior to putting on CGIV.