16 December - From the Morgan to Manhattan
While I was queuing for my
uncooked spuds and grey Brussels at The Morgan last Sunday,
the two ladies in front of me were discussing cinema visits. “What was the last film you saw?”
“I can’t remember” came the answer. “Oh, I saw Oppenheimer at the IMAX in
Greenwich but it was spoiled by being far too loud.”
Nerdiness got the better of me. “There are only 30 IMAX film equipped cinemas in the
entire world and none of them are in Greenwich.”
Just because the director chooses to use an IMAX film camera does not mean that
you will always see it in that format, it will nearly always be scaled down to ordinary 35mm film size or more likely to digital. The image quality
should be very good but if you want to see IMAX in all its 15/70 glory you
will have to go to Leicester Square, the Science Museum or Waterloo.
The projectors had to be modified to accommodate Oppenheimer because the
platters (horizontal spools) were not big enough to accommodate a three hour
film. It is eleven miles long and weighs about 600 pounds. Kodak had to set up a
new film manufacturing line for black and white film because no one had ever
done IMAX in black and white before and so did the processing laboratory.
The
conversation continued at the table.
When asked why Oppenheimer had to be so loud I resisted the temptation to say
that Atomic Bombs tend to go off with a very big bang and gave the official
explanation. Film loudness is set at what the industry calls Reference Level and
every cinema should adhere to the standards. I have heard of cinema managers
reprimanded for not sticking with the standard.
Reference Level is pretty loud with an average around the 80dB mark peaking at
110 or so but probably not for long.
In a large cinema auditorium it is difficult to get things right at every
seating position because everyone needs to be able to hear what is going on so
some might experience even higher sound levels.
Modern home cinema equipment can be similarly calibrated for Reference Level and
it is certainly too loud for some people but it definitely brings an extra dimension to the experience.
When I ran a double bill of the two Top Gun films for friends at home I reminded
them that I like to run the system at a life-like level and my father used to
take me into the test cells when he was developing jet engines in the fifties
and sixties so I know what they should sound like. One was so impressed by the
end of the session that he said he was going to buy such a system for himself,
but then I told him how much good audio equipment can cost these days!
Conscious of the possibility of hearing damage I keep a Sound Pressure Level
meter by my side if a film is likely to be noisy so that I can keep an eye on
the peaks. As expected they go over 100 for a very short time and occasionally
past 125 for so short a time that only the meter is aware of it. Those sort of
levels all the time would be dangerous but SpecSavers report my ancient lugs to
be perfectly OK. I think I am the only one of my similarly aged friends who does not use hearing aids.
Maybe that is because I have never been a headphone user. I made my first
amplifier and accompanying loudspeaker when I was only 14 years old and once
played it loud enough to have the police at my door. Only ten watts too. (The
speakers were much more efficient then what they are now.)
That’s quite enough nerdiness for now!
Note: 15/70 comes from the width of the film and the number
of sprocket holes per picture frame. Some lesser cameras are IMAX
certified. Those used for Top Gun Maverick for example. If you are still with me
at this stage you might wish to look at this
YouTube from the IMAX Waterloo
projection room. Not at all like The Odeon where I used to give a helping hand at the weekends.