Premiere: Stills have incredible shimmer in final video

[Jolard]

I am putting together a project that mixes still images and video clips set to music. The final output will be DVD. The stills are 720 x 480, and the video is analog captured at 640 x 480.

I used the storyboard function in Premiere to put it all together, and then exported the final timeline as an avi.

The problem is that the still images have incredible shimmer. It looks just awful. I know that this is most likely an interlace issue. Thinking about it here at work (the project is at home) I can think of a few possible reasons:

- The difference in resolution of the video and the stills is causing problems

- The fact that the stills are non-interlaced, while the video clips are interlaced.

- The fact that I am using 720 x 480 instead of 720 x 530 or whatever it is.

- A setting I am inadvertantly missing in Premiere.

Anyway, my question is what is the most likely cause of the problem? Are their filters or settings in Premiere that can make the difference? I tried optimize stills, but that didn't make a difference. I also tried creating the AVI with a number of different codecs, but that didn't make a difference either.

I suspect it is the fact that I am mixing interlaced with non-interlaced. Should I de-interlace my video before adding it to the timeline? Or would this cause problems down the road.

Thanks for your help!

[racer-x]

Download this PDF document and read it.
http://www.adobe.com/products/premiere/pdfs/ps_to_pre.pdf

It is packed with info about still images in video.

You probably have some pictures with a horizontal line of 1 pixel thick. This will cause flickering when viewed on TV. You can try a gausian blur on the pictures to help stop the flickering. You want your stills to be 720 x 534 for NTSC dvd.

Don't forget, read the pdf!

[Jolard]

Thanks for the link, it is actually a nice document, but it doesn't talk much about decreasing flicker in pictures, although it does have some nice advice I didn't know.

I will try the gausian blur, see if that makes a difference. Also, I am going to try rendering the stills without the video, to see if it is the combination that is causing the problem. I am not 100% sure, but I think I did render some of the stills earlier in the project without the video, and I don't think I noticed the problem until I added the clips. I will have to test to be sure.

Other suggestions I have found online:

Use flicker removal and frame blending
Make sure the pictures use NTSC safe colors


Any others?

[racer-x]

I don't think that rendering the stills without the video will make any difference. You will never notice the flicker on PC because it is caused by interlacing effect on TV. The TV makes the picture by scanning horizontal lines called fields. If you have a thin line that runs horizontal wich is 1 pixel thick, the interlace scanning has a hard time picking it up. This creates the flickering you see when viewing on TV. Something like a soccer net in the distance may produce flicker because of the horizontal net webs may be 1 pixel thick. If you apply a blur filter, it effectively makes the line thicker, wich will be easier to pick up by the scans.

This is also excellent, and will explain in better detail:
http://www.adobe.com/motion/events/pdfs/dvprimer.pdf

Hope that helps.

[Jolard]

You said I will never notice the flickering on the computer monitor, but actually I do! That is why I thought the problem was more than just simple interlace issues. The flickering is really bad on both the monitor and on the TV (and yes my monitor is a non-interlaced monitor).

So maybe I have some other really strange problem. That was why I thought maybe mixing interlaced and non-interlaced sources might be the problem.

If Premiere sees the interlaced videos, and then expects all sources to be interlaced, then I thought it might be doing something weird to the non-interlaced stills.

Anyway, I am not sure what the problem is, but if the interlace problem should not show up on the monitor, then that is not my issue.

[tygrus2000]

Deinterlace your video with the setting Interpolate Fields, then re-interlace with bottom field first. This eliminates flickering in stills in VV4 when I do my slideshows.

[Jolard]

Thanks for the suggestion Tygrus, I will give it a go.

Based on racer-x's comment about how I should not see interlace problems on the monitor, I am wondering now if it is a more significant problem.

I think I am going to start from scratch in a new project with just a few of the worst offenders, and then see if I screwed up some setting somewhere along my old project.

[racer-x]

For the record, I use stills in all my videos in one way or another. I never experienced problems like you're having. But then I mostly work with DV-AVIs wich are 720 x 480. Since you're working with video that's 640 x 480, it may be worth a try to make your stills 640 x 480. At least the video and the images will be streched the same amount.

I don't think it will work, but it might be worth a try.

[Jolard]

Well I got it to work, thanks to everyone who gave suggestions. Here is what happened:

I had created a storyboard in premiere, which included my stills and video clips. The default length for the stills was 5 seconds, however after rearranging all the stills and video, I realised that 5 seconds was not quite long enough and wanted to change the length to 6. I could not find a bulk way to do that, so went through 200 stills by right clicking on them, selecting speed and changing the duration.

Here was the problem. When you change the duration through the speed menu, you can set the duration, but it also changes the speed. Since I was extending the duration from 5 to 6 seconds, the speed was changing to 83%. Since they were stills, you would think this wouldn't matter.

But it did. This caused all my problems. The slowdown was enough to make the interlacing far more obvious. In all the slowed down stills, the jitter was just awful anywhere you might expect to see interlacing problems.

The key was that I was seeing the problems on the monitor and not just on the TV, so I knew it had to be something other than normal interlacign effects.

Anyway, in summary, if you are using stills in premier, feel free to change the duration, but don't change the speed in any way. If you slow down a still and it is outputting the result as an interlaced avi, then you could have big problems like I did.

Thanks for everyone's help. Appreciate it.

[racer-x]

Glad you sovled you problem. That was interesting.

If you have your pix in the storyboard, double-click on them. It will bring up the duration, just change and hit enter. If you want the default duration of stills to be 7 sec or whatever, go into Prodject > Settings > Render and stills. The default will be 150 frames (5 sec x 30 fps=150 frames). So if you want the default to be 7 sec, then change to 210 Frames. This must be done before inserting stills into the timeline.

Also while you're in there, tick Realtime Preview(if you have version 6.5), This will give you realtime preview when you hit enter while viewing the timeline.

[Jolard]

Thanks racer-x, some great suggetsions. I knew I had to set the default duration before moving the stills to the storyboard, and that was my problem. I didn't decide to change the duration until after I had the storyboard all organized, so I didn't want to re-import to the storyboard.

However, I only right clicked on the images in the storyboard, and the only option on the right click menu is the speed option. I didn't think to double click and open the images and set the duration there. I have learned, thanks for the suggestion.

Anyway, the good news is it all looks incredible now, I finally got it synced up to the music and it is looking great. Now onto DVD-Lab for the final authoring!