This question is often asked, what is the best way to get high quality ophthalmic surgical video?
1. Firstly, always leave the recorder running, as interesting things happen suddenly, and turning on the recorder after that mises the key event! These days with large capacity hard disk recorders, I leave it running through the whole operating list - and if nothing of interest occurred, then one can simply wipe the track andrerecord over it the next day!
2. Camera- currently the Sony 3 chip (EXWAVE HAD) cameras still seem to be the best. There are a few new HD cameras out, which are both very expensive, and till most venues get facilities to project HD, maynot be worth the investment
3. Link, Firewire from camera direct to recording device is best - the feed should go straight to the recorder & output from recorder to your TV monitor (not the other way round), A Composite video link, probably delivers similar quality (if your camera doesn't have firewire output)
4. Recorder - I am currently using a hard disk recorder from Datavision. This has 250GB removable drives, so you can record a few days surgery on on disk, take it out - take it to your office/home where you can copy files to PC/Mac and select the bits you want to keep. The rest are deleted. If you have a couple of spare disks, then you can be recording on the next one, whilst sorting the content of the first - so a sort of cycle goes on. Beware of recording direct to DVD, as this is already compressed to mpeg, and whilst output looks good, once you have edited (and sometimes redited more than once), there is loss of quality - the editing software basically tries to decompress the footage, and once you have edited it, recompress it, so every editing cycle has a depreciating effect on quality. Also some hard disk recorders actually compress to mpeg as they record (The Sony medical grade hard disk recorder records as mpeg), what you want is a recorder which records as a native DV stream (Datavision does that) or a relatively lossless format such as AVI - great for mac users as they are already set up to handle DV, but PC users (like me!) can still access the quality if they have the correct software - I use Adobe Premiere CS4, which allows me to import DV files directly and renders them well after editing, although if I play these DV files directly (say through Windows Media Player), the quality is rubish! But once imported into Adobe Premiere - quality is great! Codecs are a dark art which I do not fully understand - but I am here merely trying to explain what works for me (and maybe will for you).
5. Software - If you have an academic connection (Hony Lecturer, whatever), or even a child in full time education, you maybe able to get software on educational prices, which are much cheaper than market rates. I am told (unconfirmed) that Apple UK, if you ring them and say you are a NHS doc who teaches medical students, will give you a discount upto 15% - I haven't tried this being a pC use, but for some of you that may be worth trying.
6. Archiving - this is the biggest problem - Video files are huge - an if You have yaers of them, then you need terabytes of space - that is a separate topic on which I will try to post in the future!
Best Wishes
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