I tried to get my hands on as many of the projection films commonly used by members of the forum to do a side-by-side comparison for my own research. I still haven’t received my HoloLite and HoloGrey samples ($906 USD per sq. meter), but I’m tired of waiting so here are my results with the following films:
Polymex 50 micron double matte drafting film ($2 USD sq. m)
Rosco Grey ($12 USD sq. m)
firstname.lastname@example.org’s film ($90 USD sq. m)
IFOHA Digiline White (169 EURO sq. m)
IFOHA Digiline Contrast (230 EURO sq. m)
3M Vikuiti ($566 USD sq. m)
You may notice how dark the Vikuiti looks in comparison to the other films--this is not an error. The black level and color contrast are much better than the cheaper films, but without a sufficiently bright projector the image is dull (my projector is 1200 lumens). If you had a 3000 lumen projector it would look stunning. The Vikuiti is also the only film that has a restricted viewing angle. I would estimate it to be roughly 90 degrees (compared to 160-170 for average LCD monitor), which could severely limit its suitability for tables. You can see this in the images where the Vikuiti is slightly curled away from the window at its top edge.
Here are my personal opinions of the films:
*Drafting film: Nice and bright but looks washed out and has the lowest contrast ratio. Best price to performance ratio by far;
*Rosco Grey: Kind of the worst of both worlds. It’s too thick to have a bright picture, the contrast ratio isn’t all that great, and the image tends to look blurry. Inexpensive but my least favorite;
*mind.unity’s film: Brighter than the Rosco but still doesn’t quite get nice pure whites like the more expensive films or the drafting film. This is probably the sweet spot for budget projects that want to keep the costs below a few hundred dollars.
*IFOHA Digiline White: Matches the brightness of the drafting film but less washed out and with deeper blacks. This film has a very harsh projector hotspot if you are standing directly in front of it, however.
*IFOHA Digiline Contrast: Great balance between brightness and contrast, and no projector hotspots. This is my favorite of the bunch but a little pricey for hobby tables. $145 for a 45” 16:9 sheet (125 Euros, 114 cm).
*3M Vikuiti: Paired with a bright projector, the Vikuiti can match the contrast ratio and color reproduction of an expensive LCD, but with the narrow viewing angle and exorbitant price, I can’t really think of a reason to recommend it to anyone.
In summary, I would recommend no budget projects consider drafting film, medium budget projects consider mind.unity’s film, and high budget projects consider the Digiline Contrast. Note to LLP and DI users--mind.unity’s film, Rosco Grey, and Vikuiti all transmit slightly less IR than the drafting film, but still works if your blobs are nice and bright.
I did my best to get the photographs in focus and the exposure accurate, and the images below are a good representation of how the films look in person.
[EDIT] Either I screwed up my initial calculation of the price of Vikuiti or it has dropped by about 60% since I first wrote this. I’ve updated the price to $566/sq meter. Also, I changed the price of the IFOHA materials to euros since the dollar cost fluctuates (damn recession!). [/EDIT]