
1. Request for support of 60
fps frame rate.
The DCI specification document does allow for a frame rate above
24 fps. However, it allows for 48 fps only. We do not recommend
the introduction of 48 fps and would rather propose 60 fps for
the following reasons:
Although 48 fps is quite good performance wise, damage will happen
to material shot at 48 fps when transferred to video for TV and
home entertainment distribution after the cinema run. Indeed,
frame rate conversions do cause considerable damage to moving
images. A frame rate of 60 fps would yield and even better quality
than 48 fps and interface better with the subsequent TV and home
entertainment career of the movie. It will only require 25% more
bandwidth, which is marginal.
Also, since 60 fps is already an established frame rate in daily
use in the moving image industry, we would recommend it would
be supported anyhow. With so much 60 fps material in existence
and in daily production, risks may be high that proprietary systems
might emerge if 60 fps is not included from the start into the
standard. Additionally, 48 fps introduces a new frame rate into
the moving image industry. An industry that already suffers from
too many different frame rates. We would prefer to see a reduction
of the number of commonly used frame rates in the industry, given
that frame-rate conversions do a lot of damage to moving imagery.
In the actual industry we already have to deal with 24, 25, 30,
50 and 60 fps presentation speeds, let us please not add one
more.
2. Request to support full resolution,
even at higher frame rates.
Even if technology and economics may limit bandwidth for some
time to come, we feel it is not a good idea for a standard to
impose such limits. This may conduct to proprietary versions
once the technology and economics will allow for higher resolution
at high frame rates. That would be regrettable and contrary to
the goal of a standard.
We propose the standard will include an evolution path for that
future.
3. Proposal to allow for frame
rate change during the show.
Frame rate changes during the movie will allow higher frame rates
to be used more economically in the beginning (by limiting the
higher frame rates to specific scenes within the movie). This
should be possible without visible joint. The use of frame rate
changes will then probably disappear later on when the higher
frame rates become more economical, and entire movies can be
shot and run at the higher speed at acceptable costs. Till then,
frame rate changes will allow for a significantly better quality
cinema experience.
4. Proposal to support other
common existing and legacy film projection frame rates (8,
12, 16, 18, 20, 22, 30, 60) to be supported. We would like
to suggest to SMPTE to add this possibility. This should
be easy to implement (especially the lower ones) and would
be a real practical advantage of DC projection equipment
over film projection equipment. Additionally, 25, 50 and
60 fps would allow for material distributed in cinemas but
originally shot for TV, to be shown in better quality, again
avoiding the need of damaging frame rate conversions.
5. Proposal to standardize how
to represent stereoscopic 3D imagery. In order to avoid emergence
of proprietary versions. (We have learned that a SMPTE working
group has been started on the subject, which we think is
very good news)
for IMAGO, Kommer Kleijn SBC, IMAGO delegate in EDCF-T
download
digital proposal
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