picture quality loss on dvd

mojoman wrote on 3/22/2009, 1:03 PM

i created a dvd from still images with properties template set to NTSC DV 720x480, full resolution rendering quality set to Best. I matched the aspect ratio of each photo. Looks very good in the preview window and in DVDA. but final dvd has significant picture loss. Most photos look 'washed out'. I played the dvd on a large projection screen so that probably is a factor because when i play it back on a computer screen it looks pretty good. Not sure how to improve the picture quality on a bigger screen.

couple of quick questions...in the Properties window, do the settings need to be made before i start the project or can I change a setting and simply 'save' to take effect? What is the best choice for Field Order and Deinterlace Method?

Instead of choosing Render As in SVMS I chose Make Movie. I don't think that should matter.

Some of the photos in playback appear to have a flickering effect. In DVDA I turned on the Reduce interface flicker in the Menu Page Properties. That reduced the flicker I saw in the preview window but when i burned the DVD the flicker was back and is pretty annoying at least to my eye. Not sure why some photos 'flicker' and some don't. Might have to do with the resolution of the camera that took the photos.

I really appreciate any ideas on how to improve the final picture quality.

Rick

Comments

Chienworks wrote on 3/22/2009, 2:01 PM

I've seen a lot of projectors set for optimal brightness for reading powerpoint slides in a room with the lights on. This is usually done by raising the contrast and brightness up, often nearly as high a they will go. This is a guaranteed recipe for making video and photos look horribly washed out. Considering that your presentation looks much better on your computer screen i'd guess this is the majority of the problem. There's very little you can do about this in Vegas. Any adjustments you make will never recover the full quality and they'll make your video look too dark and shadowy on other displays. Much better is to get the projector adjusted instead. Lots of projectors have a few presets or profiles so that they can be set for both powerpoint-type images and video and swap between them with a couple of button presses.

A lot of flicker comes from having the original image resolution too high and moving the images around the screen. When a high resolution photo moves each frame may capture different fine details than the frames before and after it. Reducing the resolution close to the output resolution before placing the photos in Vegas will help a lot. Also, as with the standard advice to TV producers, avoid checks and stripes. Lots of high contrast detail can't be rendered properly in a scummy format like NTSC. Each frame consists of two separate fields, the first field showing the odd lines and the second field showing the even lines 1/60 of a second later. Even without movement, something with fine high-contrast details may end up flickering 30 times a second as one field picks up brighter pixels and the other picks up dimmer pixels. This causes the dreaded strobing that you've seen when a newscaster wears the forbidden striped tie.

If you're intending your presentation to be shown on LCD monitors you may want to consider creating a progressive project rather than interlaced. Render to a format like WMV and play it back on a computer connected to the projector. Without interlacing you'll avoid most of the problems completely.

mojoman wrote on 3/22/2009, 3:31 PM

Chien, thank you very much for the prompt reply. I was hoping you would read my post. What you said makes sense and explains the loss of picture quality. Regarding the flicker issue, you said to reduce the resolution close to the output resolution before putting the photos in Vegas. If my project properties template is set to 720x480 are you saying to adjust the image resolution to that? I want to be sure I understand you correctly. How do i find the image resolution of a photo once it is a .jpg file? I couldn't find the resolution in the properties window. Would i use something like infranview to change the resolution before bringing it in to Vegas?

I was hoping the flicker would be minimized when i turned on 'reduce interlace flickering' in DVDA. It looked much better in the preview window but looked just as bad when i burned the dvd. I might go back again and make sure it was on when i burned the dvd. it made a significant difference when i turned it on to reduce interlace flicker.

thanks again Chien for answering. I really appreciate it.

Rick

Sierra Nomad Photography wrote on 3/30/2009, 10:41 PM

Rick:

A few years ago when I started making slideshows I came across this problem (used another NLE, but fix is the same).

As mentioned, resize your image to 720x480 (if NTSC). I'm not familiar with the image editing program that you mention, but resizing images is pretty basic, and I would assume that it can do it. I also found that saving at 300 dpi improved quality considerably, though I don't have a rational explanation as to why.

The above will vastly improve your images. But you may still have some flicker with "problem" images (i..e. branches, phone lines, etc.) In a few cases you may need to use a filter that "unsharpens" your image (I forget the name of the specific filter that I used - am dealing almost exclusively in video now). Experiment with your filters. I ended up with a nice "dreamy" look that I even decided to apply to some images that didn't have flicker.

mojoman wrote on 4/1/2009, 12:57 PM

thank you very much for the helpful info! I really appreciate it.