? 4 Billyboy

MrMikeC wrote on 6/28/2004, 8:58 PM
Was reading on your site about monitor calibration and everything. You say that most computer monitors do not by default have the 6500k temp setting. On my computer monitor, I'm able to set it to 6500 (makes things look a bit dark) Does this mean I can fairly reliably use the colors, brightness, etc on my monitor to gauge what it will look like on a TV? I'm having a lot of trouble with this calibration business....I tried using a regular TV as an external monitor hooked up to Vegas, and I got a great picture on that TV, yet when i tested the finished dvd on the TV in the other room, I had to bring the brightness way down and the color setting way up to get the same quality of image..I tried using the color bars that you talk about but it just doesn't seem to be working out for me...

Comments

John_Cline wrote on 6/28/2004, 9:19 PM
Color temperature isn't the only difference between computer monitors and TV's. One important difference is "gamma", it is explained here:

Poynton's Gamma FAQ

Maybe a different explanation of calibrating a TV using color bars might help as well.

Color Bars and How To Use 'em

John
BillyBoy wrote on 6/28/2004, 9:28 PM
Even if you use expensive test equipment to calibrate, each TV is a little different than the next one. If you are getting good results with your external monitor even if its just a TV and you want to get the same levels on your other TV you need to take it a few steps further.

Assuming you calibrated both TV 's as a first step.

Now to make TV 2 show the same levels and colors as TV 1 you need to feed BOTH the same test signal at once. Head for your closest Radio Shack, BestBuy or CircuitCity and get yourself a S-video distribution amplifer or something similar.

http://www.radioshack.com/product.asp?catalog%5Fname=CTLG&product%5Fid=15-1172

You feed some signal from your camera or DVD player to the input and a output to each TV. S-video is better, if your equipment doesn't have it RCA plugs will do. The box comes with both.

The reason you need this little device (you may be able to rent one) is trying to feed a signal to two TV's without amplification is one TV will get a strong signal and the other won't. With this kind of device both get the same signal strength which is critical for what we're going to do next.

Now lug your little TV into the room where your big TV is, set up the little one side by side to your larger TV about 4 feet apart so their magnetic fields don't interfer with each other, let them both warm up at least 20 minutes.

Using your DVD or camera find a nice strong image, a person or persons at a medium closeup is best so you get the all important skin tones.

Now tweak the settings on each TV one at a time until the pictures on both match as close as possible. They may be quite different at the start. That's normal.

It will take some trial and error and don't settle for doing the adjustment with just one image. Try several. If your TV's have some kind of on screen readout of what brightness, contrast etc. is (they usually have some graphic bar) write the numbers down before you start and also once you're happy with the results.

I did this on one rainly weekend and it took well over a hour back and forth before I was happy. The good news is once your external monitor and your big TV match you won't get into endless knob twisting any more. You may want to recheck them every six months or so. The second time around it only takes a few minutes because you're only going to do very minor tweaking if any.
Spot|DSE wrote on 6/28/2004, 9:48 PM
Read Color Correction for Digital Video if you're interested in exploring some of the more detailed aspects of calibrating a monitor. Video University has some good tips too, as does this site which is a post, but filled with a great FAQ on gamma, luma settings, etc.
craftech wrote on 6/29/2004, 4:54 AM
Unless you do what BillyBoy suggested you will not get a video that looks great on virtually every monitor. That goes for Video University's methods as well. They don't work well. The reason is that factory default settings for televisions in people's homes aren't adjusted according to the standards for NTSC calibration. The contrast and brightness are usually set too high. Given the fact that most people don't use a setup disc to adjust their televisions, a customer gets what appears to them to be a washed out viideo more often than not despite the fact that it was set up "properly". Some televisions have better comb filters, etc that have a greater "latitude" for compensation so it appears to look better on some televisions than others.
If getting a video that looks good or great on "most" televisions is what you are after you will need to "ballpark" the color corrections including the gamma, render test loops, and try them out on as many different televisions as you can. It's a lot of work.

John
MrMikeC wrote on 6/29/2004, 2:53 PM
My question is about this blue filter -

"What you'll need is either a Wratten 47B Blue or a Rosco's #80 primary blue filter."

I called my local camera shop (Ritz camera) and the guy said the only thing he has is something with the number 80A on it and is meant to be just screwed onto a camera lens - will this be suitable for the part where I'm required to use that blue filter?

I understand there should be no difference between the left bar and the middle bar when setting the brightness on the TV, but should that third bar be highly visible or just barely visible? As I'm able to bring the brightness up quite a bit without affecting the other two bars.

MiKe
BillyBoy wrote on 6/29/2004, 4:17 PM
Funny! I went to Wolf and Ritz camera too (owned by the same outfit) and they didn't have a clue and thought I was nuts. You can find both filters on the web if you really want one. Its usually just some sheet that looks like colored platic. The trick is it you have to have the correct filter or it won't work. The idea is suppose to be if you look through the right blue filter then the cyan and magenta bars should match In brightness. The filters mentioned absorb greens and to a lessor extenent red. Once you do the other adjustments, don't sweat the color adjustment. If you can find a filter or have monitor or TV that has a blue switch fine, otherwise you can skip it and instead tweak if needed while a medium closeup in on screen so you can see a range of skin tones.

Here's a web site that shows the filter sheet and also has an abriavted method for adusting.

http://shop.store.yahoo.com/cinemasupplies/leepowrstfis.html
MrMikeC wrote on 6/29/2004, 4:30 PM
ah ok, thanks for letting me know, I won't buy that filter if it wont' work haha...what about as far as the three pluge bars - should the grey one be just barely visible or fairly prominent above the other black and superblack bars?
MrMikeC wrote on 6/29/2004, 4:36 PM
I just read on another forum:

If you are viewing from the NLE timeline (through a camera) , you have to consider whether your camera and DVD player output the same brightness level. Also some NLE's (Vegas 4 as an example) have incorrect color bar values - the right pluge bar in Vegas 4 has RGB of 42,42,42, rather than 24,24,24.) It has been corrected in version 5.

So does this mean I now have to worry about the signal going from the computer, to my camera and then to the TV as he talks about the brightness issue - I'm just using a Canon ZR20 as the bridge between the computer and my TV via the firewire setup in Vegas...

BillyBoy wrote on 6/29/2004, 5:34 PM
If you eyeballing it then just barely a tiny bit visible difference on a TV. You'll see the difference better off a computer monitor so remember that you DON'T or shouldn't see such a difference on a TV. Then again that depends how good a computer monitor you got. I can see a fairly big difference looking at a LCD monitor. You may not on a CRT monitor.
MrMikeC wrote on 6/29/2004, 6:43 PM
Well now i'm actually looking into getting one of these video monitors - my question is what's the difference between a production monitor and a presentation monitor?

see this link on B&H:

http://www.bhphotovideo.com/bnh/controller/home?O=breadCrumb&A=FetchChildren&Q=&ci=1844

it has two categories, presentation and production - what is the difference besides price?
MrMikeC wrote on 6/30/2004, 9:53 AM
http://www.displaymate.com/

Is this good? it got a bunch of accolades it seems..