How To

May 14, 2001

Analog Cards vs. FireWire Input
by Lowell Kay


So you've gone out, purchased a DV editing system and are now cutting footage. First off, you are part of the new generation that has embraced this new technology, so congratulate yourself. Secondly, you are on the front line of a generation of filmmakers that will have to figure out what does and doesn't work with this new system. Apple's Final Cut Pro is one of the amazing new programs that will allow you to edit your media. It may seem simple on the front end but if you're serious about editing, there are hidden elements that can save you time and money -- if you know about them.

Final Cut Pro is aimed at a wide range of users, from consumers to professionals, and each individual will make different demands on the program and the system. What makes Final Cut Pro an excellent editing interface is that there is very little difference between a digital video (DV) and a high definition (HD) system. They use the same keyboard commands, windows and have a similar workflow.

When the G3 came out, users were able to bring DV into the computer via FireWire a protocol developed by Apple that allows for the transfer of up to 50MB of data per second. FireWire allowed drives to be hot swappable and made it easier to transfer data to multiple machines. It was an amazing jumpstart to the new world of low cost, digital editing. But is FireWire the best way to handle video when you need it to be frame accurate?

Have you ever tried to assemble edit in FCP and found that you are off by one or two frames. Most DV decks currently are not frame accurate when laying back to tape. If you are using a DSR 20, 40, 11 or 60, you do not have a timecode input, which is extremely important if you want to layback with accuracy. The latest generation of decks from Sony, the DSR 1500, 1600 and 1800, all have this feature and will be frame accurate but if you are using one of the earlier decks and are laying back to tape for an audio sweetening session without this frame accuracy, it could be disastrous. To achieve the best results, make sure that your deck has timecode input.

Final Cut Pro is a very powerful non-linear (NLE) editing application. Because of its power, professional editors have taken this program seriously and pushed it to its limit. We have learned more about what FireWire is capable of and how it reacts in certain situations. Here are some suggestions that will help you get the most out of your system.

At Dr. Rawstock, we use an RS-422 device control to control our decks and maintain the most accurate timecode when capturing. Most computers that you purchase today do not have a serial connection built into the hardware. You are going to have to purchase a G-port or a Stealth card that replaces the modem. This port is an 8 pin mini din that is then converted via a cable to a 9 pin serial connection that's on the back of you deck. To check your timecode accuracy, make sure that you have window burns or that your deck has the ability to display the timecode that comes off the tape. Check to make sure that the window and the burn are exactly the same. If they are not, you will have to create an offset in the Device control window under Preferences, by typing in the correct number of frames that, plus or minus, that you are off. When using a deck and a converter box, expect to have to adjust your timecode (TC) offset.

Analog cards offer more flexibility for your system. They can compress the media so that you do not have to store as much information and they also use a different codec than Apple's DV codec. Aurora has a base card, the Igniter, which is S-video and RCA audio I/O. This card is great for film projects because it can make use of compression and it uses MJPEG as its codec. You can bring in media from this card, and then transfer it to another system that does not have the hardware installed and still play back the media. Since this card is not real-time enabled, you don't loose anything by only having one card for multiple systems.

The MJPEG codec that Aurora employs is very important because of a timecode issue during transitions. When you create a dissolve in FCP and you are using non-drop-frame timecode, the program changes it to drop frame timecode during the transition. This is a bug in the software and there does not seem to be a fix for it at this time. When you use an analog card, this bug does not occur! This is a big deal for projects that are dependant on someone other than the editor to finish the sound or add elements outside of FCP. When using this card, you can compress your media and take advantage of smaller disk space. By doing this you will save money on your disk drives too.

Another nice feature when using the Aurora card is that you can have clips that live on the timeline but have different compression settings. You no longer have to keep everything in Online or Draft, but all your clips will still have to use the same codec in order to play. Otherwise you will have to render them.

The main key to your success is not which system you purchase, but understanding the system. Know its limits and where you can push them. Most importantly, if you are purchasing a new system, expect a break-in period for you and the machine. You'll have to get used to editing on a new system. If you have a deadline that has to be met, use something that you are comfortable with and do not change your system. More projects have failed because of this than any other reason.

Take classes to help speed up your understanding of the system that you hqve purchased. Read books and search the Internet for tips that will make you a more informed editor. Most of all, work with the system and you'll begin to understand the time that it takes to create a good edit. If you are a beginner, expect that your editing will take up to four times as long as you think it will. Professional editors can anticipate how long a job will take, but that took years of experience and knowledge to learn.

Lowell Kay is the president and founder of Dr. Rawstock, an equipment rental and sales resource in the field of film stock sales and non-lienar equipment. They also offer training, instruction and tech support for a variety of applications.

copyright © Lowell Kay 2001

This article was originally published at Dr. Rawstock and is reprinted here with permission.

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