Stairstepping
 

I processed some footage in Vegas and noticed more
stairstepping than usual. It was around/over
peoples' faces and clothing, and around their eyes.
Even on the front of a bride's white dress, and along the edges of her arms. The footage received color correction and sharpening.
Any ideas? Could it be because I put the sharpen
filter first in the chain? This was followed by color corrector,
brightness and contrast, levels, and color curves.
It wasn't the cameras seeing as two different
cameras were used. And it happened indoors
and out. I deinterlaced the footage and that
only made it worse.
What increases stairstepping and what
decreases it?
If it would help, I could email out a couple
jpegs to anyone showing the problem.

I noticed this problem once when rendering to MPEG2 and the "quality" slider was not at 31 (all the way up). Can you give more details about how you were rendering?

Hi Edward.
I was at the "best" setting. I guess I can't say for sure
that I didn't switch something different from what
I usually do. Made DV AVIs.
Here's the interesting thing. It wasn't like the
usual stairstepping. Along the edge of her arm, for example,
there were the diagonal lines, but then they were
crossed by diagonal lines going crossing at
about 90 degrees. So the resultant effect was
like tic-tac-toe lines up and down her arm edge.


\ / \ / \ / \ / \ /
\ / \ / \ / \ / \ /
\ / \ / \ / \ / \ /
\ / \ / \ / \ / \ /
\ / \ / \ / \ / \ /



And there were patches like this below on some faces and on a
white dress and a black suit coat.


_ l _ l _ l _ l _ l _ l
_ l _ l _ l _ l _ l _ l
_ l _ l _ l _ l _ l _ l
_ l _ l _ l _ l _ l _ l

Dave, can you post a screen shot for us to look at?

Cheers
Aaron

NTSC DV is based on 4:1:1 color sampling. While the luminance (black and white) information is sampled at the full 720x480 pixels, the chroma (color) information is sampled at a resolution of only 180x120. The sharpening filter may also be revealing the color filter stripes used on the imaging chip on a single chip camcorder (assuming it was shot on one.) Either way, I would suggest not applying the sharpening filter.

John

I don't have somewhere to post. Are there any persons
I could mail a few JPGs to? In one the bride's entire dress
is covered with these squares. It's from the AVI. Shot
with a 3CCD Sony. It's not on the original imported
footage. It appeared after I did some color correction.
Just wondering if anyone has seen anything like this.
The color correction was done at the "best" setting.

I found this link. This is what the patchy areas look
like. On people's faces, arms, clothes. But just patches:
not all over. Take a look at this Shure mic PDF. It's the
blue picture I'm referring to.

http://www.shure.com/pdf/userguides/...pg_mics_en.pdf

I know that, for making *stills*, the preview window
should be set at "best full". Does the preview window
setting (e.g. "good", "best", etc.) affect in any
way the quality of *video*. I am under the impression
it does not, but I just want to make sure.

Where are you previewing the footage? On your pc? On your external monitor? Or as a final product OUT to . . . what DVD. . VHS tape . . or what?

Dave your comments on the function of the various options for Preview woke me up . . . I know I have to have the Preview window "relax" to its naturl size. I do this by carefully placing the cursor of ne of the corners of the Preview window and and carefully double clicking the mouse. This gets the Preview Window in what I call its"Relaxed" state - meaning it will expand OR contract to what it wants. Pulling it manually to a size, I can get lucky, and i'll convince myself that it is "okay". Now, with it in this "proper" size I've noticed a whole load of Previewing issues just melt away .. or should that be vanish! Or Dissolve or fade . . .

Yes the correct relaxed size for capturing stills is a must . ..

Try it . . It might work . .works for me ..

Grazie

I'm referring here to Vegas' preview window on the
PC when rendering video. The setting here, being
"Draft", "Best" or whatever, this does not affect the
results, does it?

No, it doesn't effect the finished product/render . .I wanted to asscertain if you were making a comment on the Final product/render OR that which you are seeing in the Preview.

If your finished product/render looks good, then you are okay. It will be the way you could be "viewing" your work, hence my attempt to explain the options around Previewing.

So, please tell us if the final render .. do a small piece . . is good or not. View this on something "other" than Vegas or anything PC - yeah?

Lets start there.

Grazie