image quality problems with wj-mx12

[TechnoLust]

Q: I'm seeing white streaks in the video image. The streaks are most visible on the whitest parts of the image, and the streaks look like comet tails (except they don't get wider, they're rectangular). The tails/streaks go towards the right of the image from the bright areas they emanate from. What can be causing this?

Background: I'm using S-video inputs from my computer. 1 input is the s-video out from an ATI Radeon 9700 Pro (AGP card). The other s-video out is from an InnoVISION GeForce4 MX440 (PCI card). I then use a 100' "Comprehensive" brand s-video cable to the projector. The two source cables are fairly standard 6' s-video cables you find bundled with the video card.

Prior to using the mixer, I had a Recoton S-Video switch SVS1000 that I was using to look at the different outputs, and I didn't see the streaking problem. Same cables.. all I did was swap out the switch and put in the MX12.

Also, the brightness of the image from the MX12 seems to be only about 80% as bright as the original sources when I had them going through the switch. And yes, the Fade control slider is fully at IN. :p The colors seem less vibrant, too.

I do notice one thing... the PCI s-video output is appears to be about 90% of the size that the AGP card s-video output is. (When I switch between the sources, the PCI output is literally not as large on the screen.) Both images are 800 X 600 internally before coming out the s-video outputs. For comparison, the s-video output "size" of the AGP s-video output is about 95% of the size of my set-top dvd player output. Heh, maybe I see scan converters in my future??!! Why aren't all these sources the same size?

Should I be looking at the mixer as being the problem?? Are the s-video size differences causing the problem? (BTW, the mixer has a green light for the sync warning, so the sources are certainly "clean" enough... I presume.)

Thanks in advance for your insights!!
-TL

[TechnoLust]

Well, at the risk of short-circuiting your efforts to give some thought to what could cause that kind of streaking/smudging... the problem has gone away. I just wish I knew what I did to fix it. After reconnecting the sources to the mixer tonight, and retesting again, the smudges are gone. I considered the possibility that it was because I'd reversed the sources (in terms of what jacks they're going into on the back of the mixer), but I tested that last night and again tonight and that had no affect.

But, I'd still like to know why my sources don't take the same amount of space on the screen. When using the superimpose features, I get a false border effect because one source is smaller than the other.

Anyway, I'd still like your input on the smudging so I know what to look at if the problem comes back.

Thanks,
-TL

[Primebase3]

hmmz maybe the problem is further down the line : the projector maybe?? try it on a tv for preview to see what it does.

small tip but I ain't a big tech head :) hope it helps


peace

[holly]

Why one source is larger than the other:

What is over/underscan? (http://www.vjcentral.com/show/634)

[TechnoLust]

Yes, I understand what overscan and underscan are, but what boggles my mind is that all 3 of my s-video sources are different sizes. I'll have to check the driver options to see if there are any scan adjustments I can make on the s-video outputs.

I'd like to avoid getting into having to lug scan converters with me too, but perhaps that's what will be required.

Also, to answer your question about the projector... it shouldn't be the issue... it's only a year old, InFocus LP500 with all of 40 hours on the bulb. :p

-TL