mxo2 mini and LCD
by Bret Williams
on
Oct 29, 2009 at 7:02:49 am
I've just gotten a 1080p vizio lcd to go with the mini and it looks fantastic. However, I'm new to the whole LCD thing (we're still SD tube tvs at the house) and was wondering something about the setup.
I'm running HDMI to the LCD. And I'm using a DVCProHD 720p24 sequence with P2 720p24 material. Nope, they didn't add pulldown on import. Part of the reason I got the mini and the LCD, because my DVCam solution won't output 24p to my old SD monitor. Anyway, so I get everything setup 720p24. The mini is outputting 720p, the seq is 720p, the material is 720p, etc. But on the LCD it looks like it's stairstepped. A smaller version of the stairstepping you see on SD video on a HD screen. It's being blown up a bit. But I thought 720p media on a 24" 1080p monitor should look fairly pristine. I suppose the Vizio is doing the upconvert on the fly to 1080p and isn't doing a very good job?
When I switch the output of the mini to 1080p it all looks great. Like I expected. Is this normal? When I watch HD cable on the Vizio some of the channels are 720p and they don't exhibit the same stairstepping as when the mini sends it a 720p signal. Also, I have to switch the mini to RGB if I use 720 or else the Vizio sees it all as green and purple.
Here are a couple closeups of the LCD stairstepping. One image is 1080p output from mini, the other is 720p, and the other is 720pRGB. If you look at the letter M the stairsteppig is pretty glaring.
Re: mxo2 mini and LCD by Shane Ross on Oct 30, 2009 at 5:43:36 pm
Well, it sounds like the Monitor sucks at cross converting 720p to 1080p. But the MXO2 Mini does that as well...the cross conversion. And does it better. So if that works, use it.
My HDTV does a HORRID job of upconverting SD DVDs too. But my HD DVD player does a great job...makes them look like they ARE HD...so I use that.
Re: mxo2 mini and LCD by Bret Williams on Oct 30, 2009 at 7:00:48 pm
Just got off the phone with the very helpful Marco at Matrox. The stairstepping may be an issue with the monitor. But here's a new kicker. It does do the upscaling to 1080 very well so I just output the mini at 1080. But when I'm outputting 1080, it shuts down the analog channel. I get no svideo analog output from the mini. We ran through the settings on the phone and he couldn't get it to happen either. I'd like to flip back and forth on the lcd between AV input and HDMI to see what SD and HD look like, since most will be watching my videos on a sd DVD in widescreen. Have you tried outputting 1080 on the HDMI, and analog out at the same time?
Re: mxo2 mini and LCD by Bret Williams on Oct 30, 2009 at 7:26:29 pm
On second thought, it's definitely not the monitor. If I output SD to the monitor via HDMI, it looks better than if I send it 720p. Softer overall, but ZERO stairstepping at all. If the monitor were having trouble upscaling 720p to 1080 then don't you think it would have twice as much trouble scaling up 480p? Instead, it's scaling up of 480p is some of the best I've EVER seen! Kinda the reaction you had with SD playback on your HD DVD player vs. your monitor doing it.
I'll bet I could show 90 percent of my clients this 480p image on the monitor and tell them it was Hi-Def and they'd believe me. Not so for the 720p output from the matrox. Me thinks I have a defective unit. Wonder if I should go back to a previous firmware too.
Re: mxo2 mini and LCD by Shane Ross on Oct 30, 2009 at 7:36:19 pm
Marco's a good guy.
I don't have the MINI, but when I did test it, I did test HDMI and Component out on my Plasma...720p and 1080i footage. But my monitor is a 720p Panasonic Plasma, so different monitor. Things looked great. And when I demo'd the unit on a 1080p monitor at LAFCPUG, it looked great. 720p and 1080i stuff. No stair stepping. Not sure of the model of that.
Re: mxo2 mini and LCD by Bret Williams on Oct 31, 2009 at 12:36:01 am
Hmm, you know I was seeing even slight stairstepping in 1080. You can see it in those pics. Those are actually fairly large graphics. But there shouldn't be one single pixel even visible around the edges of the titles. I mean, I'm looking at Law and Order on the same monitor from a 1080i broadcast and the intro graphics are so incredibly clear it looks like an eps file in Illustrator. And I'm sure it's a pretty mpeg compressed stream at that. I can't even see an artifact.
I'm still not sure if it's the monitor or the Matrox, but I traced the stairstepping to the 24p sequence. I'm new to a full 24p workflow, but I jumped into this project halfway and upgraded some gear so I could monitor the 24p.
But oddly enough, it's the 24p that is messing with the sharpness and stairstepping. With the matrox set to 720p 23.98 and the sequence being 720p 23.98, and the matrox output set to 1080, the image is ever so slightly stairstepped. (If I choose 720 it doesn't matter what the sequence is, it looks like a web video or sd scaled up with no interpolation at all. ) But if I copy and paste the sequence into a 29.97 sequence and switch the matrox outuput to 29.97, then everything is crystal clear. Although the video cadence is a mess because FCP isn't adding the most elegant pulldown.
But I thought LCDs were supposed to be able to handle 24p? And I thought that was the whole point of me getting the mini was to do things like work in 24p and be able to monitor it. I thought the monitor would just add pulldown, or the mini would add pulldown, like a DVD player. I think what's going on is some sort of fancy frame blending that has gone awry.
