DV Info Net

DV Info Net (https://www.dvinfo.net/forum/)
-   Open DV Discussion (https://www.dvinfo.net/forum/open-dv-discussion/)
-   -   Suggestions on Chroma key !! (https://www.dvinfo.net/forum/open-dv-discussion/357561-suggestions-chroma-key.html)

Shahzad Mian September 3rd, 2009 08:00 PM

Suggestions on Chroma key !!
 
hi, i wanted to know where to buy a chroma key background from and wat type of material. can i hang the green background in my rooms wall with the help of some double sided tape. which software would be best to remove the green background. following are my equipments.

Sony sr11
1000w halogen light kits x4
Rosco diffusion and tungsten to daylight filters
42" 5in1 light reflector
Adobe premier, ultra


should i be lighting the background directly with the halogen lights or make it diffused or converted to daylight color temperature ?

Paul R Johnson September 4th, 2009 04:54 AM

light the subject as normal. Make sure shadows are not prominent on green screen. You may have to adjust your normal angles, or move the screen, or subject to achieve this. Then light the screen to make it bright and even - hopefully any shadows will be removed. Get rid of any creases. Add some backlight to the subject if you can to get some sharp edges onto the subject.

For software, I'd use Ultra every time! By comparison, the keying features in Premiere are quite basic.

The other things in your list won't really be needed. You set colour balance in the same way you normally do. The green background is just a convenient colour that can be keyed, and is unlikely to be on the subject.

The key to keying is having a good solid, bright background. Ultra can cope with small imperfections when you set the sample areas, and can manage to deal with shadows to a degree, but it's best to not have them in the first place if you can.

The reflector might be handy if you need to bounce some light, but I suspect it won't really be very handy without some light sources shining in the right direction, and you won't have much spare to even do that.

Shahzad Mian September 4th, 2009 08:09 AM

thanx paul, any suggestions from where to buy a chroma key background ?

Oren Arieli September 4th, 2009 09:53 AM

B&H sells portable (pop-up) Botero backgrounds. Blue on one side, green on the other. I don't know how far they will ship it though.
botero green screen

Shahzad Mian September 4th, 2009 10:08 AM

well will those portable backgrounds be practical for shoots or should i go for a 10x12 or 10x20 etc muslin ones. wat about EEFX.COM - Chroma Key Green Screen Backdrops* (Foam Backed Fabric) these with some foam fabric, r they any good ?

Jonathan Jones September 4th, 2009 02:18 PM

Quote:

Originally Posted by Shahzad Mian (Post 1311413)
well will those portable backgrounds be practical for shoots or should i go for a 10x12 or 10x20 etc muslin ones. wat about EEFX.COM - Chroma Key Green Screen Backdrops* (Foam Backed Fabric) these with some foam fabric, r they any good ?

I have a botero portable 2-color pop-out and have used it to great effect, but find it a pain to use. I also have a much larger single-side green botero muslin screen. The muslin in these wrinkles like nobody's business, making it a lengthy process to set it up and attempt to minimize the wrinkles and makes it more of a challenge to key. There are some tricks one can use to straighten out the muslin a little bit, but it can be time-consuming and proves to be counter-productive to the quick ease of a pop-out setup.

I bought a 10x12 kit from EEFX.com a couple of years ago and I love it. It has provided the best and easiest keying experiences I've had so far. Fairly quick to set up, easy to get smooth lighting, and easy to key, all of which makes for a far more efficient workflow for both pre and post, IMO.

-Jon

Shahzad Mian September 4th, 2009 03:12 PM

thanx jonathan, do u have any pics of ur chroma key setup, it would help me a lot to see the eefx background and also have an idea of its size.

Guy Cochran September 4th, 2009 03:22 PM

1 Attachment(s)
I have the SR11 and have shot a few tests. One thing that's worth mentioning, well two, things. Make that three....

1) If you're shooting people tilt the camera sideways to get more resolution. Most people are tall and skinny :)

2) Consider the Blackmagic Intensity card. With it you can connect an HDMI cable and record Uncompressed or less compressed, right into Premiere.

3) Make sure to lock your exposure to keep the Auto mode from changing your settings.

Here is the video I shot with the SR11 and the Intensity Pro. Sony HDR-SR11 Chromakeyed- uncompressed HDMI capture with Blackmagic Intensity Pro and Reflecmedia on Vimeo

The Manfrotto head I use to tilt 90 degrees is the 410

Shahzad Mian September 4th, 2009 05:16 PM

thank u so much Guy Cochran for the tips, i will definitely try the 1st and 3rd point. currently i am buying a chroma key background so i would ask u wat do u think about the eefx.com foam fabric green background ?

Guy Cochran September 4th, 2009 05:37 PM

I've heard good things about the EEFX stuff. Depending on how good your keyer is, you may not need to worry so much about small wrinkles, only heavy ones which create shadows. Those are the challenge to key. Westcott has some decent folding backdrops too that you might want to look at http://www.fjwestcott.com/products/a...head=chromakey
And be sure to drop by the Lowel EDU site and check out their quick article on lighting green screen Lighting for Green Screen on Location

Shahzad Mian September 4th, 2009 05:55 PM

thanx man u r such a great help. i think i should go for the eefx green background as its also more cheap then the westcott sheets.

once i sticked a green paper chart on the wall directly towards the sun and my friend was about a foot away from it. i imported the video in adobe ultra and it came out really really good, i tried getting it keyed in premier and after effects but they weren't a match for adobe ultra. i think u should try adobe ultra if u haven't.

Jonathan Jones September 4th, 2009 10:12 PM

Quote:

Originally Posted by Shahzad Mian (Post 1312359)
, do u have any pics of ur chroma key setup, it would help me a lot to see the eefx background and also have an idea of its size.

Right now, I'm afraid I don't have anything of use. Some small images of it in use in the background, but only partially and not in any way that really shows its size. I think I'm going to have to get more diligent about taking production photos.

-Jon


All times are GMT -6. The time now is 12:32 AM.

DV Info Net -- Real Names, Real People, Real Info!
1998-2024 The Digital Video Information Network