CompuServe Thread

#Fields vs. Frames

14 messages in this thread
#189172From: Bruce WaterfieldSep 5, 1995 11:20 AM
Can anyone clarify for me when to render frames vs. fields. All of my animations are being recorded to Beta SP. Should I always be rendering to fields? Also I was wondering: If I have sequential bitmaps (rendered as frames not fields) and am outputing this to tape via a Video Post sequence, can I select the Fields setting in the VP render dialog box to output the saved frames as fields or would I have to re-render those previous frames from scratch to change them? Bruce
#189211From: Sep 5, 1995 2:07 PM
Bruce: >> Can anyone clarify for me when to render frames vs. fields. General rule: whenever rendering to tape, render fields. >> can I select the Fields setting in the VP render dialog box to output >> the saved frames as fields or would I have to re-render those previous >> frames from scratch to change them? No, you cannot add fields to previously rendered images, unless you reduce the length of the animation in half and use every other scan line. Greg Pyros
#189230From: Bruce WaterfieldSep 5, 1995 3:56 PM
Thanks alot for the info- Bruce
#189373From: Bruce WaterfieldSep 6, 1995 10:54 AM
Greg- I have one more question about fields vs. frames. I re-rendered my animation using the field setting (except for the holds on the first and last frames which I rendered as frames) and the motion does appear more fluid than before. The problem is, however, that when the camera moves in close and the objects move, I get a severe "stutter" from the objects' shadows. Does this have to do with field order, or are there drawbacks to using field rendering in close up work? Thanks again, Bruce
#189376From: Robert C. RitgerSep 6, 1995 11:42 AM
Bruce: Shadow stutter can be a result of having the SHADOW-BIAS-ABSOLUTE set to ON in your 3DS.SET file. If this is how you have it set try switching it to OFF. There is a brief description of what the variable is all about in a comment in the 3DS.SET file. Try this out and let us know if your shadows stop flickering. There are other things to try but this one is worth doing first. – Bob Ritger
#189390From: Bruce WaterfieldSep 6, 1995 12:22 PM
Robert- I checked my 3ds.set and the shadow-bias-absolute was set to off. I also went back and checked the frames I had rendered ( as opposed to the same animation done in fields) and noticed the stutter there also, though less pronounced. Any other ideas? Thanks- Bruce
#189429From: Robert C. RitgerSep 6, 1995 5:25 PM
Bruce: If you are net-rendering then you've got to check each machine. A flicker can result when one machine has the bias set to on while the other slaves have it set to off. Next up I try two things: 1. Check smoothing groups. If orthogonal you may want to remove the groups. Where did the geometry come from which exhibits the shadow stutter? For me it is invariably a model that I have imported into 3DS. 2. If the flicker is still around I usually select the faces which are a problem and do a CREATE/FACE/DETACH. As a final answer this one usually does the trick. – Bob Ritger
#189591From: David RhotenSep 7, 1995 1:35 PM
Also, I've found that if the plane on which the shadow falls is large and made up of only a very few (and therefor very large) faces, that telsselating the plane a bit will smooth out shadow edges. Dave
#189789From: Robert C. RitgerSep 8, 1995 11:40 AM
Dave: I'm going to add that tesselation move to my list of fixes, thanks. – Bob Ritger
#189511From: David StinnettSep 7, 1995 2:30 AM
PMJI, but I think you mentioned using a utility to interlace two images together a few days back. Could you possibly lead me to it…? We have the need to interlace (alternate scanlines) several series of images. Thanks. David, BLUR
#189583From: Sep 7, 1995 1:01 PM
David: >> I think you mentioned using a utility to interlace two images together >> a few days back. Could you possibly lead me to it…? We have the need >> to interlace (alternate scanlines) several series of images. There are two options that I know of to do this. One involves creating an alpha map of every other line in 3DS and using it to combine the images in Video Post. The other is a 32-bit stand-alone DOS program Gus wrote called Fieldify.exe which takes the scan lines from alternate Targa files and combines them into fielded images. Much faster, but $50 more! :^) Greg Pyros
#189586From: David StinnettSep 7, 1995 1:12 PM
Thanks, I'll try the VP method for now. David
#189261From: MARTIN G FOSTERSep 5, 1995 5:32 PM
Bruce, if you have the rendering power, I'd render frames with object motion blur and scene motion blur. This is very expensive, though, but is the preferred way in some circles. Do you have a lot of fast moving cameras and/or objects? What kind of project/client of we talking?
#189330From: Bruce WaterfieldSep 6, 1995 6:09 AM
For this animation, there are alot of fast moving, tumbling geometric shapes, but little camera movement (a basic dolly move). Is there a specific formula for calculating the amount of motion or scene blur for a project? Bruce