Editing and Quality loss

I have a basic question, but an easy answer.

I have a short QT movie, DVCPRO codec, 720x480. Due to many reasons, one of the scenes, an establishing shot, has no letterbox. (Most people never notice.) But I'd still like to add one.

Here's my question:

1. If I go into FCP, and add a letterbox and reframe the shot by lowering it, and then export to QT, will I lose any quality? (I lower it so the top of the building doesn't get cut off in a funny place.)

1a. Does it make a difference if I reframe by adding a widescreen filter, and then adjust the position of the shot in the Filters tab. (I think it's called "offset."

1b. What about using Derek's technique of adding a letterbox by using a shape (aspect 100x72.5) and inverting it, and then repositioning the shot by dragging it lower -- essentially using the Motions tab to reposition it (but actually dragging the image+wireframe.)

2. The shot is a tilt up a building. If I want to include the whole shot -- starting at the very bottom of the building, and tilting to the very top -- I have to use keyframes and add motion, which can be done either way. Does that movement affect the final quality?

Thanks for the help.

Mike

DV is lossless for straight copies.

a small amount of loss will be incurred when you add an effect and have to render.

this is the same if you are working with your original rushes,
or an Exported file,
so go ahead and add your effect.

the techniques will all *pretty much* produce the same effect, quality-wise.
certainly the shot itself will be the same in all instances.

what you have to keep an eye for is the letterbox itself.
some techniques *may* give a crisper result,
but what really determines this is which line of video the letterbox sits on.
if you were to use a very simple crop technique for instance, and do it manually, you might get a slight fuzziness to the border.
if you went into the clips motion settings and chose round numbers for the crop settings it could get better

i haven't used it much, but i would hope that FCP's own widescreen filter would conform to the best settings, and give sharp edges

you'll only be able to judge this on an external monitor, not on the canvas.

the same goes for the RE-FRAMING of the clip.
once you have re-positioned it,
open it up into the viewer, and go to the motion tab.
adjust the X+Y co-ordinates to the nearest whole, even numbers.
the image will look sharper
(again, you'll only see this on an external monitor, not on the canvas.)

if your shot is moving from beginning to end, this wont really matter.
but if you keyframe in a hold, then hold on even, whole co-ordinates for best results.

i can't comment on the quality of the borders using Derek's technique,
but it does give you the least amount of real-time monitoring of any WS technique, and the longest render times.

for one shot this is OK,
but for a series or shots, i would (and do) use either 2 cropped slugs above the image, or a Mask i've made myself in Photoshop.

when done, export your sequence as a self-contained QuickTime Movie, using "Current Settings" (this is the default)
this method of exporting guarantees no re-compression.


nick

Thanks for the full answer.

I'll check for the even numbers -- I never knew that mattered so much, but I guess if other numbers force every pixel to get interpolated, it would of course affect quality.