CompuServe Messages

Glen, Actually I don't know about the 525 lines vs. 486 lines. Someone else will have to answer that one. But, per the CCIR 601 standard for digital video the resolution is 720×486, it is also 486 lines with most frame buffers such as the Targa+ and the Vista, Max etc. Anyway, field rendering produces better results because of the fact that all NTSC devices are interlaced. Interlacing refers to the fact that each frame is composed of two sets of scan lines, one odd and one even. The electron gun in the TV first draws the odd set of scan lines in 1/60th of a sec. and then goes back and draws the even lines producing 30 frames per sec or 60 fields per sec. If your animation is _frame_ rendered then on every frame both _fields_ will be the same producing a 30 frame per second animation. If your animation, on the other hand, is _field_ rendered then each field will be slightly different resulting in basically a 60 frame per second animation – much smoother, especially noticeable on both fast objects and objects traveling horizontally ascross the screen. On some animations you can't even tell the difference and on others it's easily apparent. If you're going to video you should really always field render, it does take slightly longer but it's not twice as long, and it's worth it. If you have the chance you should do some tests and see for yourself. I've been wondering what's going to happen when HDTV becomes the standard. Since it is a non-interlaced format I wonder if the frame reate will be changed. Because really, interlacing makes the animation more smooth than if it were not interlaced. So while interlacing is bad for a computer display where nothing is changing too quickly, it's good for a system where motion is prevalent. DM