Best still image quality

John McCully wrote on 11/4/2003, 12:49 PM
Using Vegas 4 (and DVDA for (1) below) how do I obtain the best possible 16:9 still image quality when the target output is (1) a DVD to be shown on a regular wide screen compatible TV and (2) a projector such as the InFocus Screenplay 7200 Projector.

I have lots of pixels to begin as I shoot still images using a 5 megapixel Sony F707 camera and import into my computer, file dimensions 2560 x 1920 pixels. Obviously I need to crop but to what dimensions?

Comments

RichMacDonald wrote on 11/4/2003, 1:28 PM
I'm a little shaky myself, so I'll wait for someone else to supply the magic pixel count, but it might be a good time to revive the "should we crop before import or should we let Vegas crop?" debate. It may have been resolved, however a quick scan through the forum archives shows a "less than definitive" discussion :-) Or is it just ongoing...?

I, for one, don't bother to crop beforehand. I import the clip at full resolution and let Vegas do the work for me. It works fine, plus I can pan and zoom, recrop, etc, at a later date.

Counter arguments might be:

(1) You're making Vegas do all that extra work over and over again, i.e., for each frame. I don't know if this is true or not, but I'm guessing the Sonic programmers aren't dummies here.

(2) Graphics packages use better algorithms to resize the still. Once again, I don't know if this is true or not. Note: The Sonic folks say you need to render at BEST quality in order to use the best resizing algorithm. However, we don't know what this best algorithm is, afaik.

Actually, the Vegas manual its a bit lacking: It gives an example of the calculation for NTSC and PAL, but not widescreen. Searching back through the forum archives, there is a post by a Sonic rep saying the pixel count is the same. It would be nice to see that added to the manual.
BillyBoy wrote on 11/4/2003, 1:36 PM
Keep in mind that Vegas isn't really designed to be a still image enhancement application. For that something like Photoshop shines. So for best results you may wish to do some prep work prior to importing images into Vegas. If you're just talking a little cropping, probably doesn't matter. However if you source images need work, I think you'll get better results in a application designed for that purpose.

All that said, afterwards, you can still touch up a little using the Vegas filters. As far as BEST verses GOOD rendering choices that too depends on the type of image, if or not you're going to pan/zoom. That can be debated till the cows come home.

If you're starting with a ultra high quality large number of pixels image like 2560 x 1920 pixels I would suspect Photoshop would do better reducing it to a more managable size compared to Vegas. Again, if you are going to pan or zoom the image, then leave it about 2-3 times the final fame size. If you're not going to pan or zoom I'd reduce it in Photoshop or whatever you're using first.

I explained the difference between BEST and GOOD countless times. Its misleading in the name. It isn't always better, rather different. Its all in how Vegas works the image.
RichMacDonald wrote on 11/4/2003, 1:50 PM
>As far as BEST verses GOOD rendering choices that too depends on the type of image, if or not you're going to pan/zoom. That can be debated till the cows come home.

Take a look at the thread: http://www.mediasoftware.sonypictures.com/forums/ShowMessage.asp?ForumID=4&MessageID=198829. There, SonicDennis states:

"Always render using "Best" quality (set in project properties) so the best image downscaler is used."

I may be reading into his words, but I assume that Vegas uses different algorithms to downscale larger images, e.g., linear (preview quality?) vs bicubic (best quality?) interpolation. If so, there is no debate: When using hi-res stills, the quality setting does matter, even if you're not panning and zooming.
Bill Ravens wrote on 11/4/2003, 2:39 PM
Trick question, right?

DV is, by definition 720x480....and I think you mean "resize" not "crop".
NTSC sTV will not show rez better than this, so, no point in making file sizes any bigger since sTV won't show it anyway.

Now, if you wanted to show on HDTV, then the biggest size(AKArez) you can display on conventional HDTV sets os something like 1024x780. In this case you wouldn't use DV at all, because of the 720X480 restriction, but something like MPEG2 or MP9, but, then you'd need a computer to play it back.
John McCully wrote on 11/4/2003, 3:47 PM
I truly appreciate the responses to my question.

No, BillRavens, I don’t think this is a trick question. The image I import into my computer is 2560 x 1920 pixels which is equal to 720 x 540 if I maintain the original aspect ratio, I think. But I need wide screen, 16:9. If I simply resize without constraining proportions I introduce distortion. So first question, what is the DV NTSC Wide screen pixel dimension ratio? Actually, a ratio of 16:8.8 seems to fit better than 16:9 without black edges in the Vegas window. So if I crop in Photoshop to 2560 x 1408 (equals 16:8.8 ration) I have maximized the pixel count and I let Vegas render using the DVDA NTSC wide screen template. I also resized that file in Photoshop, maintaining proportions, to 720 x 396 and rendered that using the DVDA NTSC wide screen template. When I render using the DVDA NTSC wide screen template the image on my monitor looks soft and not very wonderful compared to the original no matter what original pixel count I use (maintaining the 16:8.8 ratio of course).

If I render using the Vegas HD 1080 60i template the larger files look hugely better. As I mentioned in my initial post my plan is to project these HD images using a HD projector, not just my computer, and TV limitation are not an issue, I think!

I still don't really know the ideal ration, i.e. 16:9 or 16:8.8 and for resizing I don't know if it's better to let Vegas resize, after I get the ratio correct for wide screen, or to do it in Photoshop. Of course I use Photoshop for all the other image manipulation like contrast, brightness, what have you.

Am I making sense?
Chienworks wrote on 11/4/2003, 3:52 PM
You could also let Vegas take care of the problem for you. Make sure the project properties are set properly for the output you want. Drop the picture onto the timeline, open up the Pan/Crop window for that picture, right-mouse-button click in the middle of the frame, and choose "Match output aspect ratio". Vegas will automatically crop the picture so that it fills the output frame perfectly with no distortion. You can then re-crop if you wish. If you keep the "maintain aspect ratio" button on then you will maintain the proper shape.
John McCully wrote on 11/5/2003, 8:41 AM
That's very cool Chienworks, worked like a charm. Excellent solution. I completely overlooked the pan and crop tool. Many thanks for your suggestion, truly appreciated. Last night I rendered a series in HD 1080 30p and the still images are stunning, video not so flash though so now I need a HD video camera, right!