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eBrito
10-06-2003, 10:41 PM
Hi folks;

I started with my VT3 in a live production last weekend at church.
I loved it but the picture quality is so poor.
I know it's not a VT3 problem, i think i have to setup my camcorders, lights... and that's why i'm here, trying to get help with that :D

I have 3 Sony PDX-10 (good cams i thinks) and the church has fluorescent lights.

I'm using the cams with default values and didn't change any proc amp settings at VT3.

When i press the "Illegal" buttom on the VT Vision, the entire picture looks illegal.

Does anyone have an ideia where can i start to get it working well?

Jim Capillo
10-07-2003, 04:42 AM
Something like this is hugely difficult to diagnose without actually seeing the output. Can you post a few jpg's of the output or email them to me?

More info on the equipment, please. What are you using for camera cables? S-VHS, Firewire, Composite? How long are they? I'm not familiar with those cameras. Do they have color bars?

Flourescents can wreak havoc depending on what amount of daylight is coming in the church..... we recently had problems like that covering meetings at City Hall and we solved the problem by changing the bulbs to more friendly daylight color temperature tubes.

Hard to say what's going on without seeing a picture, though....

eBrito
10-08-2003, 06:38 PM
thanks
i'll post some pictures here.
i'm using S-VHS cables, 100 foot.
yes, the cams has color bars, but it's different then bars that come with VT3.

Jim_C
10-08-2003, 07:32 PM
Turn on the bars from the camera then choose auto adjust on the proc amp.

Danner
10-09-2003, 11:41 AM
if your illumination will stay somewhat constant color wise, do a white balance on all your cameras.

eBrito
10-09-2003, 07:26 PM
Here some pictures:

This one with default settings:

http://www.addnewark.com/construction/frame.jpg

This one, i adjust exposure, same place, same lights and now, more red than before.

http://www.addnewark.com/construction/frame3.jpg

I'll try that, adjust the Proc Amp and do White Balance.
I let you know what i get.

Thanks
Emerson

eBrito
10-13-2003, 10:21 PM
i used auto proc amp with cam's color bars and did the maual white balance. it's just a little bit better, but... still poor.

i think i have very good cams and now, i don't know what to do.
sometimes i think i need more lights but, if with these lights i'm getting high brightness if i add more...

what else can i do? pray to the Lord? :p

Jim Capillo
10-14-2003, 04:37 AM
This looks like a lighting issue to me. In the first picture, the guy the second from the right is awash in some sort of light from above and back. I don't know if it has a gel on it or not, but it certainly looks like it does. The guy on the far right has it on half his face. The rest of the picture looks OK to me.

The second picture has the guy on the left unlit and the guy on the right extremely hot.

You need to take the gels off (if any) and balance your lighting.... the church will have to take this into consideration if they want their services to come out well for TV. The lighting TV requires is far from the usual quasi-theatrical lighting you typically see in churches. If this is your first foray into TV lighting, I'd suggest you do a search on the web for an instructional book, or, if your local cable TV has someone with the experience, take a few classes on lighting. Be careful with the latter though - you may end up with someone who will tell you the were lighting tech for the Today Show........ :rolleyes:

eBrito
10-14-2003, 09:56 AM
Thanks Jim;

I think you got it. I have to change my lights.
As i told you, all church use fluorescent lights. I don't know how to explain it but the bulbs are inside a box with a opaque plastic in front.

You right. That's my first foray into TV lights.
We can add or change our lights, i just need to know exactly what to do.

I'll look for some information around the net.
Thanks

mgrusin
10-14-2003, 11:13 AM
The tricky thing is if you have several different types of light; fluorescent, tungsten, and daylight all have different "color temperatures". The human brain will see them all as white, but the cameras see them as markedly different colors. You can white-balance the camera(s) for one type of light (and sometimes an even mix). But if you have an uneven mix of light types you will see color problems, especially on skin.

If this is your problem, you could try tinting the different lighting sources to one color temperature with gels. For example, if the dominant source is tungsten (spotlights), you can put specific gels on the other lights (fluorescent tubes and daylight through the windows) to tint them towards tungsten. This can be a pain and moderately expensive (last time I bought gels they were $5 for a 2'x3' sheet), but it's what the pros do when they must mix lighting types, such as shooting an interview in front of a picture window. www.rosco.com has some info on these gels, but as Jim says a good lighting book or class would probably be helpful.

Then again, I've seen worse than your example pictures. ;) Simply white-balancing your cameras with a white card at the podium should get you a decent picture with the least amount of work.

Good luck! -MG

Jim Capillo
10-14-2003, 01:09 PM
Emerson, for an immediate temporary (if not permanent) solution, I'd get a light kit and set up lights on either side of the stage and actually shut off those offending spots (if possible). Leave the flourescents on if you must, but as MG says, you'll have to white balance somewhere where both light sources are playing down. From what I can tell, it appears that there are no lights out in the audience/camera area, so the lights that ARE on on the stage are overpowering the ambient light and (1), washing out the subjects below them and (2), causing the camera iris' to close up, making the unlit subjects very dark.

A wide stage like yours calls for a flood fill situation - lighting from the audience area and lighting that is even all the way across. If you can't get a light kit, try shutting down those hot spotlights and then white balance with just the room lighting.

Good luck!

eBrito
10-15-2003, 11:48 PM
thanks guys.
i'll make some chnages there and when i'm done, i'll post new pictures here.
thanks for help me.

eBrito
10-25-2003, 03:20 AM
Well, let's start again.

After white balance the 3 cams, the picture are so much better and the same
quality in all cams but, when i turn on "Illegal Colors" on VT Vision, many white parts of the picture are showed as
illegal. To fix it, i need to turn down the exposure on the cams.

Well, if i add some lights to the set, it won't increase the problem with the white parts?

Look at the new pictures:

http://www.addnewark.com/construction/new0001.jpg

http://www.addnewark.com/construction/new0003.jpg

I need cheap solution to lighting. Does anyone know "par lamp"? could it work well?

Jim Capillo
10-25-2003, 04:38 AM
That's precisely why the lighting needs to be even and balanced. Any hot areas will either cause the camera iris to close up leaving the rest of the picture dark or if you adjust manually, the hot areas will persist. I've seen those work lights on stands available from Home Depot (and others) used successfully in many instances. They're cheap, last a long time and have easily replacable bulbs. Judging from your first picture, I'd get 2 complete units (2 lights per stand) and position them somewhere behind the cameras and flood fill the whole area. That should balance your lighting on stage, give some illumination out in the audience area and make for a generally more pleasing picture. You may have to experiment, however. Too strong and you may need to attach some tuff-spun to the front of the lights or point them up at the ceiling (if it's a fairly low ceiling) - or shut some of the lights off. That's usually the knock on those work lights - they look very directional on camera and need some diffusion over them to both knock the strength down and even it out. You've taken the first step, now get some lighting out behind the cameras and I think you'll see a world of difference.

JReble
10-25-2003, 06:13 AM
The first thing you should do is replace all the flourescent tubes in the room with GE flourescent 3500K high color reproduction tubes. These are fairly recent products from GE that will give you perfectly acceptable color rendering with your existing flourescent fixtures since they reproduce the entire color spectrum and don't lean toward the green spectrum as typical tubes do. They work great in my studio with a variety of fixtures and you can mix them with studio lighting kits as well.I've found them as good looking as studio flourescents, just not a intense in output so I have to use more. Since they cost a 10th of the lowell or kenoflow lights, that's fine with me. It may not solve your directional lighting issues but it will correct the color rendering issues. Then you could look at some new fixtures and soften or eliminate the can lights above that are really not helping things at all. For directional flourescent fixtures on a budget, check out conservation technology at the address below.

http://www.con-techlighting.com/series.asp?CATEGORY_ID=25&PARENT_ID=6

Kurt_Henning
10-26-2003, 09:23 PM
Yo E

Have you run the auto with 100% bars in the proc amp

If not, try that. It is pretty amazing and can clean up some stuff in shooting situations like yours.

eBrito
10-26-2003, 10:36 PM
But are you talking about the camcorders bars?
But how do i know if the camcorders bars are 100% ?

Kurt_Henning
10-27-2003, 05:57 PM
this depends if your camera generates bars or not.

IF you are using camcorders, then they will not. If you have a pro cam, there is a setting for bars on the left hand side near the presets and/or switches

But, you can still try the auto cal in proc amp and see what you think. If it looks bad try 75% bars.

IF that still looks bad, ingnore all my ideas --- it is the lighting

eBrito
10-27-2003, 10:55 PM
Originally posted by Kurt_Henning
IF that still looks bad, ingnore all my ideas --- it is the lighting

:)

The cam has color bars but i'm not shure if it's 100% or 75%.
I'll try both and choose the best.

Thanks

eBrito
10-28-2003, 03:16 PM
The first thing you should do is replace all the flourescent tubes in the room with GE flourescent 3500K high color reproduction tubes.
Hi JReble;
Do you know some web site where can i buy these tubes? I didn't find it.

Well, i also bought some cards with 100 IRE white to balance the cams and a minus green card they told work great with fluorescent lights.

See these links for details:
http://www.markertek.com/MTStore/product.CFM?BaseItem=WMCDS%2D2

http://www.markertek.com/MTStore/product.CFM?BaseItem=WMCDS%2D1

Well, but how our others friends sais, i'll still get some problems with directional light. To fix it, i liked the idea from Jim.

I've seen those work lights on stands available from Home Depot (and others) used successfully in many instances.
Jim, are you talking about those halogen lights?
I found a 1000W (2x500w) with tripode at home depot and it has dimmer included (looks cool).

But the halogen lights temperature wont be different from my new fluorescents 3500K lights?

Jim Capillo
10-28-2003, 03:40 PM
I don't know..... perhaps they have the color temp on the bulb. If they're different, you'll have to white balance somewhere in the middle - but be sure to WB all the cams from the same position (white card).

eBrito
10-28-2003, 10:39 PM
Thanks
I'll do these thngs and post new pictures when i'm done.

fbcvideo
11-20-2003, 12:37 AM
Have you looked into buying a lens for your camrea that will work better for florecent lights? It could help balance the out the problems you seem to have. I oo haev lighting issues in my church but I have my camrea operators adjusting the irus up or down based upon what I see on my scope. that has helped a bunch on keeping constant color and light from one camrea to another.

ted
11-20-2003, 11:00 AM
Here is a good reason for a monitor out of your camera or switcher.
We often "paint" the scene when shooting since we have outdoor, florescence and tungsten colors to deal with on location.
I've gotten really good at seeing the mix, getting the mix on the white card and balancing to my liking. I often lose some tungsten before the balance then add it back for a much "warmer" look to our shot, especially on talent.

Knowing your camera(s) and knowing how to paint them can help a lot. But a good monitor for confirmation is a must.