Barry_Green
Moderator
Curiousity usually gets the better of me, versus common sense, so I fritter valuable time away on weird tests...
Today's was: does the DVX LCD display only one field at a time?
I'd posed that as a postulation (how's that for a 10-cent word?) to try to explain why movement may seem excessively "strobey" in the viewfinder/LCD, as compared to viewing it on an NTSC TV. I know there aren't enough pixels to show a full frame, as the LCD is something like 288,000 dots in a pattern of something like 1440 x 200 (don't remember the exact specifics), so I thought maybe it was displaying only one field at a time.
To test, I made a photoshop bitmap of odd & even alternating horizontal black lines, one pixel high each, which swapped halfway through the picture (i.e., on the left side they're black=even, white=odd, on the right side they're white=even, black=odd).
Then I piped that file through Vegas and over to the DVX, and viewed it on both the LCD and the viewfinder.
I figured that if it was displaying only one field, I should see an even, flat picture: the left side would be black, the right side white.
Or, I figured that if it was somehow blending the fields together, I should get an even sheet of gray on both sides.
That's not what I got. What I got was a wildly flickering gray pattern with some discernable lines in it. The lines are most discernable in the center of the image, with a gradual ringing pattern of more-solid gray (almost looks like vignetting).
How completely unpredicted!
So now, it looks like the image is being digitally scaled so it all fits onto the grid of the LCD, which makes sense, and would maybe explain the gray vignetting. But what about that flicker? It's flickering madly, and I can't tell if it's 60hz or 120hz or what... but it seems to be saying to me that yes, the DVX is definitely displaying both fields, but as to how... that's the question. I guess it's possible that it's displaying a full frame out of each field, one after the other, running at 60 full refreshes per second.
The thing is, it's a static image, so the flickering can only be coming from the display of the odd and then even lines, and the fact that it flickers over the whole screen seems to imply that it's replacing the full contents of the screen every 1/60 or 1/120 of a second...
If anybody else wants to offer a guess as to what the heck it's doing, you can make your own file or download the one I used, which is at: http://www.icexpo.com/dvx100/black-white-lines.TGA
Today's was: does the DVX LCD display only one field at a time?
I'd posed that as a postulation (how's that for a 10-cent word?) to try to explain why movement may seem excessively "strobey" in the viewfinder/LCD, as compared to viewing it on an NTSC TV. I know there aren't enough pixels to show a full frame, as the LCD is something like 288,000 dots in a pattern of something like 1440 x 200 (don't remember the exact specifics), so I thought maybe it was displaying only one field at a time.
To test, I made a photoshop bitmap of odd & even alternating horizontal black lines, one pixel high each, which swapped halfway through the picture (i.e., on the left side they're black=even, white=odd, on the right side they're white=even, black=odd).
Then I piped that file through Vegas and over to the DVX, and viewed it on both the LCD and the viewfinder.
I figured that if it was displaying only one field, I should see an even, flat picture: the left side would be black, the right side white.
Or, I figured that if it was somehow blending the fields together, I should get an even sheet of gray on both sides.
That's not what I got. What I got was a wildly flickering gray pattern with some discernable lines in it. The lines are most discernable in the center of the image, with a gradual ringing pattern of more-solid gray (almost looks like vignetting).
How completely unpredicted!
So now, it looks like the image is being digitally scaled so it all fits onto the grid of the LCD, which makes sense, and would maybe explain the gray vignetting. But what about that flicker? It's flickering madly, and I can't tell if it's 60hz or 120hz or what... but it seems to be saying to me that yes, the DVX is definitely displaying both fields, but as to how... that's the question. I guess it's possible that it's displaying a full frame out of each field, one after the other, running at 60 full refreshes per second.
The thing is, it's a static image, so the flickering can only be coming from the display of the odd and then even lines, and the fact that it flickers over the whole screen seems to imply that it's replacing the full contents of the screen every 1/60 or 1/120 of a second...
If anybody else wants to offer a guess as to what the heck it's doing, you can make your own file or download the one I used, which is at: http://www.icexpo.com/dvx100/black-white-lines.TGA
. Now you've got me thinking and I have an idea for a second test. See, you're lowering my productivity too.
