green screen/chroma screen
by dano motley
on
Aug 13, 2009 at 2:38:15 am
i have a green screen shoot with the ex 3. it is for a web site insert of a talking head. i was going to shoot in 1080i until the clients web designer told me that it will not look right unless i shoot it in sd, based on his experience.
anyone have any experience with this...or what setting on the ex3 works best?
Re: green screen/chroma screen by dano motley on Aug 13, 2009 at 2:50:17 am
mike,
the web designer complained about some black banding if you were to use an hd setting. maybe using 1080p 30 (as you suggest)would not have this effetc?
Re: green screen/chroma screen by Michael Palmer on Aug 13, 2009 at 3:58:12 am
I believe most post personnel would like a progressive image over an interlaced image to composite. If you are referring to a letterbox black banding top and bottom I would use the 4:3 aspect ratio markers to frame with so when you are exporting as SD you will get a full 4:3 image . What is your delivery?
Re: green screen/chroma screen by Craig Seeman on Aug 13, 2009 at 4:42:25 am
For chromakey it's best to shoot progressive because the edges will be cleaner.
For web it's best to shoot progressive because computer screens are progressive and you avoid having to deinterlace.
Black banding . . . apparently the web designer does not know that 16:9 images encoding at that aspect ratio has no bands and, alternatively, can be cropped to 4:3 as Michael notes but these days 16:9 is becoming common.
Please show the web designer a movie trailer on Apple's site
another question similar to this by Greg Ball on Aug 13, 2009 at 7:06:57 pm
I'm shooting a series of presentations that will be used primarily on a client's website but will also end up on DVDs. These presentations have tons of PowerPoint Slides provided by the presenters. We're shooting the presenters on an EX1 How would you edit this? Wide screen or 4:3? Wouldn't the powerpoint need to be stretched?
I imagine that the file size will be 320 X 240. Would 16:9 be 320 X180? Would that be too small?
Re: another question similar to this by Craig Seeman on Aug 13, 2009 at 7:23:52 pm
16:9 works fine on DVD as long as it detects the flag for it.
There's no one answer for PowerPoint. It depends on the readability of the slides. You can have them in a "frame" or you could zoom in to key points if you're working in 16:9
340x180 is 16:9 but IMHO that's way too small if readability is important on the web. YouTube and Vimeo show full 1280x720p these days. If the viewer has the bandwidth then that can play without issue.
You must understand fundamentally there is no "correct" answer for an aesthetic question. You need to make readability decisions. You need to know what your bandwidth target is on the web to determine frame size/data rate.
If you don't have answers for the above you should run tests first.
Re: another question similar to this by Greg Ball on Aug 13, 2009 at 7:36:55 pm
Thanks Craig. The other issue is these presentations will be 90 minutes I'll break them down to 45 minute segments. I think full size will create huge file sizes. The audience will be industry specific doctors, so there's no way of knowing what the bandwith should be.
Re: another question similar to this by Craig Seeman on Aug 13, 2009 at 7:58:26 pm
At that length you might consider streaming server if you can afford it.
With progressive download, if they quit part way through they have to come back and rebuffer to that point.
If these are MD doctors (as opposed to the kind who are college teachers) they should have the money for the bandwidth but a lot depends on where they live as well.
In my area consumer can easily get 5000kbps down and some services offer 101,000kbps down for $99/month. Some rural areas don't offer more than 768kbps down. You're going to have to decide and part of the potential audience may be unhappy or you can offer multiple versions or, with streaming, the server may have speed / data rate adjustment.
Re: green screen/chroma screen by Clint Fleckenstein on Aug 13, 2009 at 3:22:44 pm
I disagree as well. When you're doing chromakey work you want as much information in your picture as possible. Two ways you can defeat this are a) shooting SD, and b) shooting interlaced.
I think your web guy is like many, who doesn't know the difference of different "flavors" of video. Most people who see a 16x9 SD stream probably assume it's HD because it's "wide." So he doesn't want to have a letterboxed video? No problem, shoot it with the best resolution possible and crop to 4x3.
This camera rules for chromakey work. Use the tool as it's intended. Frame it for 4x3 if that's what he requires (you can turn on the guides in your viewfinder if necessary) and enjoy a quick, easy key.
Re: green screen/chroma screen by dano motley on Aug 13, 2009 at 9:11:51 pm
just got back from the shoot and as usual...you guys are right...the web dud was a certified idiot when i met him in person. shot it progressive, put it in to key and it looks great. thanks so much for the good info...now the only question i have for your genuises is...how do you get the image to key on a web site with no backround at all. its almost like the working web page is the backround and the image is keyed in a corner with the talking head having no backround.....howdoyoudoit?
You'll have to ask your Flash designer to do that. I hope it's not your web page designer as history shows this person is likely to give you the wrong info.
