MOIRE pattern from screen door!!!

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Help.
I shot an in-depth interview. My subject was in front of a screen door looking out to the pacific ocean with palm trees in the background. The scene looked great through my camera. I didn't bring an on-site monitor. But when I replayed it on my studio monitors, it had a terrible moire pattern in the background, caused by the screen vs. the lines per inch of video. The closer the zoom the more intense the vibration of the screen pattern. It's very distracting.
All I had to do was open the damn screen door. I could kick myself. So what can I do now in post? Any experience with similar trouble? If I have to, I'll reshoot, but it will mean some travelling and re-booking, etc. Suggestions would be greatly appreciated.
I shot with Panasonic DVX100 24p 16:9 anamorphic and will edit in FCP4. Thanks.
???
 
Re: MOIRE pattern from screen door!!!

Yet another ringing endorsement as to why it's always preferable to have a monitor with you... things like this are impossible to see on an LCD.

What can you do? Well, first, what is your intended display medium? If it's going to a streaming video or computer CD-ROM playback, or other dedicated progressive display, then you're in luck -- those devices won't show the moire pattern (at least, I don't think they should...)

Otherwise, if you're planning to go to an interlaced TV with it, you're in a bit of a spot. You could try a gaussian blur to bring down the detail -- the high-frequency detail is what's overloading the TV display circuitry. It'll make everything look softer and more out of focus, but then you can pick and choose which is more distracting to you -- a soft shot or a moire pattern.

If FCP4 allows bezier masking, you could try cutting out your interview subject with a mask, and then apply the blur to only the background -- it might work... good luck...
 
Re: MOIRE pattern from screen door!!!

Our goal is to eventually go to film (transfer dv to 35mm). I was hoping that FCP4 would allow us to blur the bg so the moire would disappear.

This problem was a real supprise.
 
Re: MOIRE pattern from screen door!!!

How many frames are problematic? Some things you could try:

1) Move the clip to Combustion and derez (guasian blur or some such) the screen.

2) Export the frames to photoshop and use its superior filters and mask tools to frame by frame remove the moire. A simple blur in the masked area will work, then you can send the frames back out.

3) Can the sequence or edit around it.
 
Re: MOIRE pattern from screen door!!!

Well, we shot an apprx 45 minute interview, but we'll chop that up and use several clips throughout the doc. Not sure the lengths of each clip until we are in the editing process.
 
Re: MOIRE pattern from screen door!!!

[quote author=Dan Chapman link=board=FCP;num=1088296856;start=0#4 date=06/27/04 at 11:56:03]Well, we shot an apprx 45 minute interview, but we'll chop that up and use several clips throughout the doc.  Not sure the lengths of each clip until we are in the editing process.[/quote]

One thing you can try is one of the "film look" filters on the market. All try and simulate a certian film stock, and essentially deres soft detail and introduce grain, which may do the trick of solving the moire. Also, check the moire on an NTSC and a video projector -- moire pattern can be caused by the size of the image and might not show up on other formats.
 
Re: MOIRE pattern from screen door!!!

[quote author=dan link=board=FCP;num=1088296856;start=0#2 date=06/26/04 at 21:42:43]Our goal is to eventually go to film (transfer dv to 35mm).[/quote]

In that case you may not even have to worry about it. The moire pattern is most likely caused by the television, and on a film print it would be perfectly clear. You could probably verify by just seeing what it looks like when playing it back on your computer monitor.
 
Re: MOIRE pattern from screen door!!!

Wow! That would be great if it didn't show up on the computer. I've checked it on both my monitors two completely different sizes (one is a pro NTSC). Both have mega moire.

However, I'm sure we'll also use for video, so we'll have to deal with the problem there.
 
Re: MOIRE pattern from screen door!!!

[quote author=dan link=board=FCP;num=1088296856;start=0#7 date=06/27/04 at 18:49:07]Wow!  That would be great if it didn't show up on the computer.  I've checked it on both my monitors two completely different sizes (one is a pro NTSC).  Both have mega moire.

However, I'm sure we'll also use for video, so we'll have to deal with the problem there.[/quote]

Take one clip. Uprez it to HD, and play it in QT player at full-screen on the computer monitor. That will help you see if the eventual conversion to film will also show it.
 
Try these filters...

Try these filters...

Try the FREE "Too Much Too Soon" filters from Matt Sandström here:
http://www.mattias.nu/index2.html

In particular, the filters called BLEND FIELDS and REDUCE INTERLACE FLICKER in the above collection should help IMMENSELY in reducing the moire effect. Obviously, I wouldn't recommend using them on your film out - just the NTSC version - it will soften the image a bit.
 
Re: MOIRE pattern from screen door!!!

Just give the flicker filter in FCP a try under filters>video>flicker filter. It has a couple settings as far as removing the flicker. I have found it to work enough for me. The other option is to try the deinterlace filter which sometimes helps as well.
 
Re: MOIRE pattern from screen door!!!

I had this problem shooting a jacket with fine lines. In FCP, I used the anti-alias filter and played around with the level of the filter to balance between softening the image and removing the moire. It worked pretty well.
 
Re: MOIRE pattern from screen door!!!D

Re: MOIRE pattern from screen door!!!D

Thanks for all the thoughtful replies.
 
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