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Written by Bob H
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Saturday, 28 February 2009 09:18 |
This question was posed on LinkedIn recently and I responded in my usual disruptive style. Arguments were made against film because 4k sensors potentially don't have enough dynamic range because of the photon capture well sizes. I think I covered that in my response reproduced below:
While I agree that the dynamic range issue could be a problem, I think that the argument can get a little confused because you can also shutter more quickly and thus you don't have to fill the electron well. You can shoot at 50Hz progressive frames instead of the archaic 24Hz progressive frames. You then achieve much better motion rendering and make it much easier to shoot motion than with film.
With film the intermediate process immediately reduces quality, even with the finest sensor you can never do a 1:1 transfer of analogue media without loss of 'signal' or introduction of noise. Celluloid noise is a nature of the structure of the molecules deposited on the base, as well as the base itself, so while this noise is 'analogue' and thus more acceptable to us than digital noise, it is still present. CCDs are not without noise, but it can be more predictable and controllable as many TK's demonstrate. I think digital origination has more advantages than resolution in presenting an image that is potentially clearer and more reliable than film.
Furthermore I have walked out of films because of the poor state of the print and so I welcome digital cinema for reliable theatrical presentation as well.
If you want to see a picture that can meet of exceed that of a 1950s cinema epic then take a look at SHV from NHK in Japan (demonstrated at IBC in Amsterdam last year with a real live link from London). Their prototype camera uses four 2.5 inch (64 mm) CCDs each with a resolution of only 3840 × 2048. Using two CCDs for green and one each for red and blue, they then used a spatial pixel offset method to bring it to 7680 × 4320. Aptina/Micron are now making a CMOS sensor for NHK's next camera which is 4112 (H) x 2168 (V) and that can capture at up to 60fps. I dare say four of those will do the job!
OK, SHV will be another 5 years away before it is practical, but it is leading the charge towards very high resolution capture at decent frame rates and someone has to do the bleeding edge development to set the bar.
D-Cinema is here, it has many advantages which balance out and for me the most important issue is doing away with people saying they need to shoot a "filmic look", Cinema is my favourite medium but film is a legacy and we need to move on. I have no doubt offended someone with this post, but I think it needs to be said 24p should be put behind us as soon as possible.
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Written by Bob H
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Tuesday, 24 February 2009 13:01 |
We have a new Canon Multi Function Device (printer, copier, scanner) in the office and it is network ready. So I have configured it to upload scans to the office server for easy access. The problem is that I want to purge these files after some time so as not to clog anything up. The solution was to archive them all off periodically using a CRON job and to use a shell script to manage that process. Here is the file I created:
#!/bin/sh
tar --no-recursion -cjf ~/canon/.archive/scan_archive_`date '+%Y-%m-%d.%s'`.tar.bz2 ~/canon/*
if [ $? -eq 0 ]
then
find ~/canon/ -name '*.jpg' -mtime +6 -delete
find ~/canon/ -name '*.tif' -mtime +6 -delete
find ~/canon/ -name '*.pdf' -mtime +6 -delete
find ~/canon/ -name '*.tar.bz2' -mtime +180 -delete
fi
This creates an archive which has a unique time-stamp in its name and then if that goes ahead successfully then it deletes any images older than 6 days from the directory. It also removes any archives older than 180 days just to stop this going on forever and I am contemplating getting it to delete any very small archives because when there is nothing to archive it still creates a fragment of an archive. I must thank this site  for inspiring these commands and give them full credit.
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Written by Bob H
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Sunday, 22 February 2009 16:55 |
Now this is cool, I was just browsing looking for silicon for our products and I found quite a funky little chip from Broadcom. It is the new BCM70020 which describes itself as "a single-chip, full featured, multi-standard audio/video decoder/encoder/transcoder solution targeting volume PC and PC-based consumer electronic applications."
Not only can it encode HD from either analogue or digital sources, but it can transcode between different MPEG formats and also act as a scaler/down-converter! I think someone in the broadcast industry needs to get their hands on these quickly and create a multi-format scaler/encoder/transcoder matrix device! A few of these, a PCI-E bus and voila there you have a cool transmission ops device.
Very cool.
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Written by Bob
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Sunday, 11 January 2009 12:28 |
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A question was posted on DigitalSpy which asked: "Have there ever been or are there any "Pirate" satellite TV transmissions?" So I answered and I thought I would share my response here: It is not always required to have a license to broadcast in your target country, usually only the country broadcast from (this can be used to avoid local broadcast laws for advertising). In my past I have seen rouge transmissions, but they have usually not been pirate TV but illicit communications. More common is illegal jamming of transmissions as a result of political differences between nations, but again this more affects telecommunications than broadcast TV.
While it is possible to broadcast without permission, a satellite operator would rather jam an illicit signal rather than permit it to profit from transmission time which is not paid for. The simplest way to jam a signal is to put up a carrier spike through the offending transmission to prevent reception. It is possible to geographically locate a rogue transmission, but the resources required to do so are great and the timescales required are unpleasant. Satellite owners do not allocate such resources lightly because it would cause a great deal of disruption to their infrastructure. Usually jamming a rogue signal is enough to discourage illicit transmissions, this can be done cheaply and effectively.
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Written by Bob
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Sunday, 14 December 2008 08:35 |
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I have just found this cool tool on DigitalSpy and I have to say it is rather good. There is rarely a substitute of a site survey, but Google earth/maps has come to my rescue in the past.
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