Masking Motors

[Saleem Padinharkkara]

Hi

I am creating a new cinema which will show both scope and flat. Everyone I talked to basically says that nobody does masking now. Is that true? The projector is going to be Laser.

Look to your input about what should be the way to go.

Cheers

[Marcel Birgelen]

It depends on who you call nobody. It's true that ever since cinemas went digital, many of them either disabled their existing adjustable masking systems over time and for new builds, not even bothered to put them in. There seems to be this notion that masking only serves to create a sharp edge around the image and since digital does that already out of itself, any kind of adjustable masking is no longer needed. But that's only half of the story.

The problem with not properly masking your screen is that you always leave unused screen exposed. This unused screen will diminish the contrast of the picture. It will catch and reflect ambient light and it will make your picture look less cinematic.

Everybody can do a Power Point presentation by rigging up a video projector to a computer. If we want cinema to be more than that, then we should not lower the standards even further. So, in my opinion, you should go the extra mile and install some adjustable masking, even if you're the only one in town to still do so. You're showing the same movies as they do, so maybe it's the attention to all the little details that make people want to get back to your place?

[Steve Guttag]

I'd say that 90% of our clients use masking systems...many rather extensively (more than just horizontal or vertical but both and for a multitude of formats). Since you are in Canada, MDI (part of Strong) would make the most sense for a masking machine supplier. They have both 2-stop and multi-stop (10) machines.

If you want your presentation to look "professional" and finished, then you should always use masking. Exhibitors will always look for a reason to not spend money. This isn't to say that saving money is bad but they do not always factor in the overall perception of the performance and how to differentiate themselves from the home-theatre. Then again, even high-end home cinemas use masking too (and grand drape curtains). Personally, I think every theatre should be using curtains as well as masking and do a curtain call between the preshow and the show.

[Saleem Padinharkkara]

Thanks folks! Makes sense.

@Marcel - the nobody was basically the system integrators And it was interesting to note(and you have confirmed) that new cinemas dont do it much.

Is masking operation a specialist job? I think in my configuration, we will hv to mask the top and bottom instead of the sides when we go scope.

[Ryan Gallagher]

Thanks folks! Makes sense.

@Marcel - the nobody was basically the system integrators And it was interesting to note(and you have confirmed) that new cinemas dont do it much.

Is masking operation a specialist job? I think in my configuration, we will hv to mask the top and bottom instead of the sides when we go scope.

If you are installing a flat screen, then the typical would be to have top-only masking move it to the scope configuration. Bottom is often excessive, but might depend on the rake of your auditorium, basically you don't want the majority of the audience to be "looking down" at a scope image.

But there is still an argument for side masking too... cause anything narrower than 1.85 will have pillarboxing, including but not limited to all 178 alt content, 166, 137, 133.

220 and 200 could be made to work with just the top masking though.

I'm not an integrator... but my impression is masking is often bundled with whoever is installing the screen, and then the automation side of it might be a separate depending on their expertise. For flying screens like in traditional theatres... masking is often part of the same screen frame. (our manual sides are integrated with the screen, but our top is on a separate motorized pipe).

Bottom line, if you are trying to do it "right", and beat competition with showmanship, install the masking. Consider a drape/curtain too if you are a single-screen cinema and can afford it. Especially if you intend to show classic epics in "roadshow" format with intermissions and the like.

[Ryan Gallagher]

Also aside, in the current markets of declining cinemas... it's good to think about "other" uses of the room. A small footprint of a stage in front of the screen, a curtain that can be used as an event backdrop, ability to mask 178 ALT content for powerpoints, some appropriate lighting for "speaking" engagements, the ability to layer on some "live sound" reinforcement... even if it is just a handful of rented wireless mics and a tiny mixer. All these things help to open up alternative revenue streams.

[Gordon McLeod]

If in the GTA contact Ash-Stevenson they do screen frames and masking systems. 416 321-1412 talk with Richard
ITS (our company is a rep for NEC and GDC if you are interested in purchasing their equipment

[Jim Cassedy]

Maskings can be set up for either "common width" or "common height" screens.
Most of the theaters I've worked at were built and designed for FLAT/SCOPE film projection,
so the height would remain the same, but the sides would open for SCOPE projection. But
I've also worked at a couple of places set up for "common width" projection, which meant
that the both SCOPE and FLAT were the same width, and but the height would be reduced
for SCOPE. So this meant that your SCOPE picture image was actually smaller than your
FLAT picture, which, IMO, is not really what God intended.

There is one super-sophisticated screening room on my resume where they had four
individual masking motors, ( ! ) so that you could move the top, bottom, left, and the right
and left side masking curtains independently , if you so desired. I only used that feature
once during a corporate presentation where they wanted to have a panel of people sititng
on the left side of the stage, while projecting various images and their power-point slides
on the right side. Fortunately, both the masking and projector system I was using allowed
me to set that up. Visually, the end result was something like what is often done on TV
news programs, where you have a presenter on the left side of the screen, and various
graphics or videos appear in a DVE box above and slightly to the right of them.

[Ryan Gallagher]

Independent left and right is definitely fancy-pants. But I can totally see that benefit in a mixed use stage as in your example.

[Marcel Birgelen]

The screen in our screening room has an aspect ratio of roughly 2:1 if the masking is opened to the maximum. It uses a 4-motor system, all sides being "stop-less" as in they use a laser-based distance encoder to measure the position and a PLC to control all four motors. Having an absolute encoder in there, saves us a lot of hassles every time we need to put in a new aspect ratio and it also doesn't require any recalibration. The reason why left and right were not coupled is because some space constrains, as we didn't want to run some kind of pulley construction between both sides. So, technically we could move left independent from right, but I don't think we ever did so. In general, we try to maximize the image size by either filling the entire screen horizontally or vertically. In case of scope, we open up left and right completely and mask the bottom of the screen a bit more than the top, because in our case, this slightly improves sight-lines, especially when the room is configured for mixing instead of screening.

The system was "engineered" by myself, mostly sourced and built by my brother. We've had a few requests to make this happen on a much bigger screen, but it turned out to be too expensive every time, especially in a world where moveable masking is being though of as a "nice-to-have" rather than a "minimum equipment list" item.

For a screening room, running a lot of different content, among it a bunch of independent stuff, having 4-way movable masking is almost a necessity, but for most first-run theater operations, two-way masking is often sufficient. If you have a very high room with a screen in a constant-width configuration, only having the top masking moveable may be sufficient for most cases.

Personally, I'm a sucker for constant height configurations, where scope is definitely larger than flat, but it depends on your room geometry if that's achievable or not. In case of our screening room, that wasn't really an option, so we've chosen the "best of both worlds". Ironically, the biggest format on that screen is 2:1, which is also an aspect ratio I rather despise for all the good reasons to do so.

[Ryan Gallagher]

Constant height installs with a scope screen definitely cover far more formats with fewer masking motors.

to get the same coverage with flat screens you really need the side masking too.

[Frank Cox]

I just have my screen masked off at 2.39:1 since that's what fits under my ceiling and comes close to the walls on each side. Basically, the room was built for a scope-sized screen even though it was originally a paint and wallpaper store. Guess they were thinking ahead to when I would show up!

To get the masking right I just projected a scope test pattern on the screen and we built the masking to fit around it.

[Marcel Birgelen]

I just have my screen masked off at 2.39:1 since that's what fits under my ceiling and comes close to the walls on each side.

So, whenever you show a feature in flat, you actually move the walls inwards to make the room fit the screen?

Back in the days, the place I worked, the two biggest rooms were about equal size in capacity, but one screen was common height whereas the other was common width. We would actually plan movies according to aspect ratio. We even had a lens turret on a Vic5 stuck in scope for a while, so that made decisions easy. It also became the room without commercials and trailers. It took a while, but people actually started noticing we weren't running any pre-show ever in that room for half a year or so.

[Frank Cox]

So, whenever you show a feature in flat, you actually move the walls inwards to make the room fit the screen?

Doesn't everyone?

[Dave Macaulay]

Probably get a lot of flack for this.
I'm not opposed to masking, it does look better with than without in most cases.
Most cinemas around here now install "floating" screens, the sheet wraps around an outer tube frame so there's no structure around it like typical screens laced out to a surrounding frame. No fixed masking is needed to hide the lacing that is invisible behind the sheet.
A black drape is hung behind the screen bottom down to the floor to hide the stuff on the floor like subs and the frame support structure.
Usually they cut off (electronic masking) a bit of the top of the flat image frame and the sides of scope (within the safe limits utilized on every movie to keep principle action away from the edges) depending on the actual screen ratio, to get a larger image on screen with smaller pillar or letter boxing blank space. This may be "wrong" - but so many things in commercial cinemas are "wrong" yet accepted. Not an excuse, however the installation cost and maintenance problems with movable masking can't be ignored.
So in my opinion, don't install masking. Put the saved money into the sound system or a projector upgrade.
I'm old so I remember "the big house downtown" cinemas having drop curtains, sheers, and full movable masking. There was a whole dance with them opening and closing for trailers, snipes, shorts, and features. All manually controlled by a real projectionist who stayed in the booth the entire show threading and rewinding reels of film and doing changeovers. Some had staff pulling ropes backstage operating curtains, sheers, and masking.
Current practice with a video preshow then ads then trailers... there really isn't any use for sheers or a curtain.
And a floating screen without masking looks fine to me and from the lack of complaints looks OK to the patrons as well.
I'm not buying the "image degradation from reflected light" theory, deal with stair and exit lighting hitting the screen first.