Quick fields clarification!....

	Re: Quick fields clarification!.... by Kevin Camp on Apr 29, 2008 at 3:43:48 pm [Jimmy Brunger] "I've done the drop into comp>set comp fr rate to 50fps and stepped through using each diff variant of interpret footage...It appears to not have fields, as every other frame is static. However, when I change the field separation there is a slight shift on the image. Have I got this right - if footage is progressive in it's origin or deinterlaced then changing interp footage shouldn't make any difference to the image? So why is this footage looking different? Also, part of the image look a bit 'torn' and jaggy no matter how you interpret it..does this mean it's been poorly deinterlaced?" if you see every other frame is a duplicate when you double the frame rate in a comp (and no frame blending is applied) then the footage is progressive. the shift you see when changing the field separation settings is probably due to the incorrect setting of separating fields for that footage (incorrectly choosing to separate fields will degrade the image). the torn, jaggy look of some footage despite the settings sounds like poor deinterlacing, as you thought. [Jimmy Brunger] "If anything DOES have fields I want to combine the fields so everything I have is progressive (don't want to be doing any interlaced renders) so do I need something like Re:Vision's FieldsKit or will just separating fields and rendering progressive yield good results? I always thought that if you render separated footage progressively then you only get half the information?...though I have read elsewhere on the cow that AE still renders both fields, but both at the same time? Surely if that was the case there would be no need for something like FieldsKit..." not to steer you away from a good plugin like fields kit, but you can get ae to utilize the fields that are being 'thrown away' by enabling frame blending (frame mix, not pixel motion). when the fields are separated correctly, ae will deinterlace both sets of fields and blend the two resulting progressive frames together to make one frame. you may still get some artifacts from the interlacing, but you might give it a try to see how it works on your footage. sometimes enabling the preserve edges option in the interpret footage window can help the edge artifacts. Kevin Camp Senior Designer KCPQ, KMYQ & KRCW Respond to this post   •   Return to posts index