Chromakey MSP 12

saultopaul777 wrote on 5/3/2015, 11:47 PM
I am just learning to do chromakey and I have a Logitech HD Pro C910 and my OS is Win 7..... I SERIOUS need some help as well as good advice. I am using a green screen and have watched everything under the YouTube sun on chromakey but it still is not coming out good. I need to make some teaching DVD's for some students. I don't have too many or if any people that knows about chromakey.

Comments

Steve Grisetti wrote on 5/4/2015, 7:47 AM
Can you post a sample of your results and link to it so we can see what results you're getting? It's hard to address specifics without knowing specifically what's not working for you.

Meantime, here are some general guidelines:
1) Make sure your green or blue background is evenly lit and the color is vivid.
2) For best results, also ensure your actor is well lit and that he or she is not casting shadows on the background (or wearing clothes that are the same color as the blue or green screen)
3) Web cams, because their video can be highly compressed, do not make for the best, cleanest chroma key results. Your HD Pro might work -- but if you're getting a ragged edge between your actor and your background, that may be why.

Beyond that we can get more specific when you gives us more details on what is and isn't working for you.
DocSatori wrote on 5/4/2015, 10:58 AM
I made a couple of thousand videos with a Logitech webcam using chromascreening techniques and SMS 10,11, 12 and 13. Could you be clearer about what " it still is not coming out good" means, please?

Until then I'd be guessing as to how to solve your problems.
Here's some guessing:

1. You're still getting your chroma colour - green - along the edge of your subject.

Apply a second chromakeyer to that aura by zooming in and taking an 'eyedropper' sample to get the colour to reduce it more.

2. You're getting unevenness where your chromascreen is.

If your screen was not lit evenly, because of your light positions, shadows from your subject or non-flat or wavey screen:

Try saturating the colour of your chromascreen and possibly apply multiple chromascreen effects as for number 1, above.

3. Try to record at the camera's highest resolution. Your choice of camera was not the best for chromakeying as although you may think it's capable of 1080 p, its pixel density is low and will leave some chroma colour pixels. A better camera would have obviously yielded better results. A web cam is really a poor choice for this technique if you need high quality results. Nonetheless, they are fine for tight budgets - but don't expect HD results. It will drive you crazy trying to achieve them.

4. Try to put your subject as far back as you can in the frame during editing to reduce the halo around them.

5. Use the blur feature on your subject and apply just a small amount of blur. This is not the same blur as appears in the chromakeyer effect.

6. Use backgrounds and images similar to your chromascreen colour to make any bits of chromascreen you can't get rid of blend in a little, or look like the background is causing a glow or reflection on your subject.

7. Don't look for perfection. If the content of your video is interesting enough, people won't be as distracted by the flaws as you might worry about. You won't get Hollywood level special effects from a webcam.

8. If your subject is moving about across the frame and the light and shadows are changing, you'll simply have to learn how to keyframe from one major change to the next as you apply the chromakeyer.

9. A keylight from front and below to light shadows under your subject's face and one from above and behind to light your subject's shoulders helps immensely.

10. Do NOT saturate your image while recording using the Logitech 'Webcam Controller' software. Try to stick with the 'webcam controller' defaults.

11. If you have a patch that is more or less static where the chromascreen is and your subject isn't - just use the cookie cutter feature to cut it out completely.

12. In a similar way, you can use the cookie cutter tight around your subject(s) and cut away everything that is superfluous outside the box. If your subject is moving, you'd have to keyframe the cookie cutter of course.

13. Have your subject and chromascreen as far apart as practical to focus on your subject and create the chromascreen as out of focus. This also reduces chroma colours being reflected and bounced onto your subject- If your chromasreen is smaller than your final project screen ratio, crop off the parts of your set that extend beyond the chromascreen itself.

I could go one, but Steve's advice is very good as well as the multitude of free tutorial videos online. I will look for your messages and see if I can answer more specific questions if you post some.
saultopaul777 wrote on 5/4/2015, 1:15 PM
Thank you Steve but I do not have anything finished to show... in short, parts of my green screen is coming through my background and my picture look fake like computer generated. Could be my cam or lighting on my green screen. Is there a special type of light bulb to be used to keep the color looking normal? BIG THANKs
saultopaul777 wrote on 5/4/2015, 1:20 PM
HEY Thank you Doc,

My face as well as the rest of me.... It does not look normal, it look computer generated but not natural like most videos. THANK YOU SO MUCH and I will copy/paste and saved it.