Blue Screen

10 replies [Last post]
Christian Lett
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Joined: Apr 26 1999

My film making collegues and I (Chris Thomas and Peter Swinson) have just finished some test sequences with our new blue screen.

The screen itself was bought from a textile store in Birmingham and so isn't designed for blue screen work. It's 10m of 1.3m (approx) cotton which I gave to a local seamstress to make more manageable.

We hung it from the ceiling and made it taut at the bottom using a couple of weights. Lighting (behind the subject) done with 2 500 Watt halogen lights on either side, filtered with blue tungsten to daylight gelatin.

This provided ample light (the screen itself is about 2.5m square so is good enough for close - medium work) for the shots.

Shots were composited in MediaStudio pro 5.2 and the result, although a timy bit fuzzy round the edges, was great.

Costs: £22.50 for material.
£13.00 for work.
£25.00 for lights.
£10.00 for gels.

Total: £70.00 approx for a blue screen solution.

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Christian J. Lett
[email=clett@nationalexpress.co.uk]clett@nationalexpress.co.uk[/email]

Christian Lett After Effects and Maya Artist www.quarterlightpictures.com

ChrisBitz
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Joined: Jun 8 1999

Could you post something to the web? I'd love to see how good it is..

I've also been toying with idea of the difference matte..
As far as I understand it, If you have a subject moving past a static background, it will hide the static background, and only show the moving object?

I've always wanted to do something with an apparently miniture person walking around in a giants room! ;)
What would be the best method?

Chris.

chris thomas
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Joined: Apr 23 1999

I'll see if I can bring a sub 10Mb clip in for you do download.

The best method for your minature person walking around in a giants room would be to have a gigantic, evenly lit blue screen, and have the person walk about. You could also do it with a really small bluescreen (like Christian's), but the little guy's movement would be locked to within that small space.

I did manage to catch a couple of 'making of' programmes, which showed you how they managed some of the effects for The Borrowers and Titanic. If you want that kind of realism, you'll need to win the lottery first! On the kind of budget that Christian and I are working on, we'll be hard pressed to do a seventies 'Starski and Hutch' car chase scene!

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Chris Thomas.
chris@computer-manuals.co.uk

Chris Thomas. http://cptv.co.uk - over 30 minutes of streaming video to bore yourself with!

Tarun
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Joined: Apr 29 1999

Even if the blue screen is small, what about resisizing the keyed out figure? You can then have a vertically challenged person in the giants room...
And for the realism edit cut ins of persons expressions, feet, pov shots... a short shhoting script could look like
1.. ecu eyes looking up
2.. ls matted small person looking up to the window
3. ecu eyes lookin up and then exit frame
4. tracking low angle (shot with widest angle lense you have) shot of the room
5. ls matted small person walking around

this is just acheap way of creating the illusion... but if this was a dream sequence in some bunuel film... it would have been terrific...

andy_winton
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Joined: Jul 6 1999

Hi all,

I'd like to see the results of your
blue screen tests.

When I did it the results were so bad
I ended up making my own hand made masks
for the final image to get rid of any
noise.

(Then again, I didn't have a very good
blue screen or very good lights either

fun,

andy

------------------
--
Andy Winton
(see my Video at idlechild.net)

chris thomas
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Joined: Apr 23 1999

At last, and by popular demand (well, two of you), I've finally managed to set up a wee bit of webspace so that you can download one of our short shorts.

http://freespace.virgin.net/cp.thomas

It's 7.5MB, 56secs long, and it was shot on a TRV900, and edited with MSP 5.2, via a DV Raptor on my home built PC. Compressed with MS-MPEG4, which hopefully won't be a problem.

Chris.
(p.s. Very happy to be mentioned in CV mag, Bob. Couldn't stop showing it to friends for days!)

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Chris Thomas.
chris@computer-manuals.co.uk

Chris Thomas. http://cptv.co.uk - over 30 minutes of streaming video to bore yourself with!

Christian Lett
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Joined: Apr 26 1999

Hang on, Chris - where's my Director's credit??? To anyone who downloads the KungFu movie, I directed it. Not the greatest acting (or blue screen work) ever I know but what do you expect for an hour of making it up as you go along!

By the way, I recently got hold of a demo of a piece of software called Zbig Chromakey Software. This has to be seen to be believed. The results you can get are astonishing, including:

* Shadows
* Transparency (through semi-transparent clothes as well)
* Unevn blue/greenscreen lighting
* Fine detail (like hair)
* Full colour correction

All are fully parametric but it does 99% of it for you. Using the tutorial images supplied, the results looked almost seamless. Check out their site for more details: http://www.zbigvision.com/prodc.html

It's expensive (£1350 approx. for NT standalone and £1000 approx. for Adobe AfterEffects) but if we ever need to do any serious bluescreen effects, I think this will be the software we'll use.

If you buy the software, mention my name in any correspondence - maybe I'll get a discount

------------------
Christian J. Lett
[email=clett@nationalexpress.co.uk]clett@nationalexpress.co.uk[/email]

Christian Lett After Effects and Maya Artist www.quarterlightpictures.com

chris thomas
Offline
Joined: Apr 23 1999

Oops! Silly me.

Christian Directed it! Christian Directed it!

Feel better now?

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Chris Thomas.
chris@computer-manuals.co.uk

Chris Thomas. http://cptv.co.uk - over 30 minutes of streaming video to bore yourself with!

andy_winton
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Joined: Jul 6 1999

Hi,
Downloaded it! Heh, looked like you
had fun making this.

How long did it take to from start to
finish to make this?

I'm guessing the sparkly bits at the end
around the hand and feet took the longest.
Was this done by hand for each frame?
What bit of MSP did you use for this
effect?

Have fun,

andy

PS: To continue on someone else's thread,
there should be some central site pointing
to everyone's work that can be downloaded.
Don't know if this has progressed any, but
I still think it's worth while.

------------------
--
Andy Winton
(see my Video at idlechild.net)

chris thomas
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Joined: Apr 23 1999

As for the shooting, I'm not sure, but I guess an afternooon (Christian?), and the editing took a couple of hours.

Yes, I painted the electricity effects frame by frame which took about 20 mins, using MSP's Video Paint software. I only did a very quick job, but the painting options in video paint are limited - nowhere near as good as Paint Shop Pro.

If you're bored, look out for the 'santa claus' frame!

If someone wants a 'central point' for links, then I'll volunteer to keep a list of other peoples sites on my website. If people want to email me, I'll give it a go.

Chris.

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Chris Thomas.
[email=chris@computer-manuals.co.uk]chris@computer-manuals.co.uk[/email]
http://computer-manuals.co.uk

Chris Thomas. http://cptv.co.uk - over 30 minutes of streaming video to bore yourself with!

Obi Hayve
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Joined: Sep 10 1999

Funny kungfu movie!
Nice to see people having a lot of fun with their video cameras (I've never been one for shooting village fetes!).
Shame about the vignetting on a couple of the shots though - looks like a bad wide-angle lens? If it is, scrap it!

Obi.