Chroma keying with a Casio EX-F1, is it possible? at DVinfo.net

Kristian Tigersjäl · March 16th, 2010, 10:42 AM

Hi people!

I'm trying to get into chroma keying abit and I've heard all this talk that you need pro gear to even be able to do ok chroma keying. The Casio EX-F1 is probably not exactly pro gear when it comes to shooting video, but it shoots a pretty darn nice video I must say, especially in good lighting. Would the output be possible to chromakey successfully or are the pro gear bastards right about this? That you need tripple cmos sensors etc etc?

I did a quick mini test in the bedroom against our blue wallpaper. The light wasn't perfect or flat so I can't tell much from it, but it looked KIND OF like good lighting could have upped the level of successfullness to something usable?

I'm just wondering, so I'm not going out to get some gear just to realize it still won't work.

Kristian

Mark Wheeler · March 16th, 2010, 11:56 AM

Sure! Well... I haven't personally done it with that camera but it should be!

The key to chroma key (no pun intended) is a VERY well lit background. Get some cheap clamp lights (a la Wal-Mart) some powerful CFL bulbs to go in them, and build a frame out of PVC pipe, clamping the lights to the PVC to illuminate the background evenly.

Kristian Tigersjäl · March 16th, 2010, 12:05 PM

Good to know it should work with a "consumer camera" aswell. Some people on another forum had me believe that expensive cameras with separate channels were necessary. I told them I wasn't looking for something perfect enough for a movie but they insisted. Thanks for the info, I thought it sounded really weird considering how common the effect is. I'll just get something greenish (hah) and try lighting it as even as possible and see where I end up.

Laurence Kingston · March 16th, 2010, 02:44 PM

You know, when you stick highly compressed video on a timeline and do simple cuts and crossfade edits, it pretty much looks the same as if you converted all your raw footage into a high quality intermediate like Cineform. It's when you start doing things like color correction and filters like chroma-keying that you start to notice the difference. Footage in Cineform chroma keys better than it does in the native format.

That isn't the most important thing in chroma keying though. The most important thing is lighting your subject and the screen properly. What you want to do is put your subject a ways in front of the screen so that there are no shadows on the screen. You want to light up the screen evenly so that there isn't multiple shades of green (or blue) which will drive you nuts when you go to key out the background.

You also want a better chroma keyer than the one comes with your editor. I use the one the comes with New Blue Video Essentials II. The one that comes with my editor (Sony Vegas) doesn't have the all important spill suppression. I also have Boris FX which has a pretty good keyer as well, though I prefer the New Blue one most of the time.

Bad chroma keying looks like a low budget effect. Good keying makes for a composite image that looks the subject is in the new background.

Kristian Tigersjäl · March 16th, 2010, 04:33 PM

Thanks for the advice. I've heard the built in keyer isn't very good so I'm going to look at alternatives and see if THIS together with a properly lit screen will work any wonders for my "consumer" camera. I did some minor tests already that wasn't very well lit so I can't say much about it, it was also shot in VGA resolution that I'm sure didn't help things. A new test with good light and 720P and I'll give it another go.

Yes, the spill was something I noticed because even when I managed to key out most of the blue area I still had small blobs of spill here and there that made a so-so key look plain horrible.

It's kind of amazing how different the words are about this. Some people laugh at it saying don't even bother, other say it is possible and can get quite good with the right light.

Laurence Kingston · March 16th, 2010, 08:49 PM

Well I for one love the current generation of point and shoot still cameras with HD video modes. Mine is the Canon SX-1 IS, but there are ones from several different manufacturers that are of similar quality.

I also have a pretty decent video camera (a Sony HVR-Z7) that I use for work. How do the two cameras compare? Well the Z7 was about six grand and the SX-1 IS was less than 1/10th that, so you would think there would be a huge quality difference. Not really though.

Don't get me wrong. I'm not about to sell the Z7. I really love that camera. It records to either tape or flash memory, has phantom powered XLR audio inputs, separate limiters on both channels, rings so you can easily adjust things by feel when you're shooting. It shoots 60i, 30p and 24p (which I don't really like, but a lot of customers ask for). Another really important thing is that you can put the footage right on a timeline without recoding it into an intermediate and still get really good performance.

But aside from those advantages, how does the quality compare between the two cameras? Quite frankly, it is hard to tell which is which in a final render. The quality of the point and shoot is excellent. Yeah I need to recode the raw footage into intermediates, and no I can't record audio good enough for an interview, but for whipping around and capturing b-roll, the little point and shoot rocks! The quality is great. I miss the focus, zoom and aperature rings, but hey, my Z7 doesn't automatically recognize and set itself to faces. In the end, footage from both cameras blends nicely on the timeline, and the point and shoot looks very good on the timeline.

Is it as good? I would say for the most part yes it is. It is a very good b-roll camera. I like whipping around with the small camera. I can support it steadily on a small tripod and get in and out of busses and taxis easily. I can climb up steps and hills with it much more easily. I can zoom in to 40x and get some really hard to get shots. I can set everything manually with the menus. No it's not quite as fast, but it's a heck of a lot easier than lugging around the heavier gear.

I wouldn't apologize for your point and shoot. Yes there are some limitations, but the quality is much better than most people realize.

March 16th, 2010, 10:42 AM	#1
Kristian Tigersjäl Tourist Join Date: Mar 2010 Location: Örebro, Sweden Posts: 3	Chroma keying with a Casio EX-F1, is it possible? Hi people! I'm trying to get into chroma keying abit and I've heard all this talk that you need pro gear to even be able to do ok chroma keying. The Casio EX-F1 is probably not exactly pro gear when it comes to shooting video, but it shoots a pretty darn nice video I must say, especially in good lighting. Would the output be possible to chromakey successfully or are the pro gear bastards right about this? That you need tripple cmos sensors etc etc? I did a quick mini test in the bedroom against our blue wallpaper. The light wasn't perfect or flat so I can't tell much from it, but it looked KIND OF like good lighting could have upped the level of successfullness to something usable? I'm just wondering, so I'm not going out to get some gear just to realize it still won't work. Kristian

March 16th, 2010, 11:56 AM	#2
Mark Wheeler Regular Crew Join Date: Jan 2007 Location: Hemet, CA. Posts: 87	Sure! Well... I haven't personally done it with that camera but it should be! The key to chroma key (no pun intended) is a VERY well lit background. Get some cheap clamp lights (a la Wal-Mart) some powerful CFL bulbs to go in them, and build a frame out of PVC pipe, clamping the lights to the PVC to illuminate the background evenly.

March 16th, 2010, 12:05 PM	#3
Kristian Tigersjäl Tourist Join Date: Mar 2010 Location: Örebro, Sweden Posts: 3	Good to know it should work with a "consumer camera" aswell. Some people on another forum had me believe that expensive cameras with separate channels were necessary. I told them I wasn't looking for something perfect enough for a movie but they insisted. Thanks for the info, I thought it sounded really weird considering how common the effect is. I'll just get something greenish (hah) and try lighting it as even as possible and see where I end up.

March 16th, 2010, 02:44 PM	#4
Laurence Kingston Major Player Join Date: Aug 2004 Location: Clermont, FL. Posts: 941	You know, when you stick highly compressed video on a timeline and do simple cuts and crossfade edits, it pretty much looks the same as if you converted all your raw footage into a high quality intermediate like Cineform. It's when you start doing things like color correction and filters like chroma-keying that you start to notice the difference. Footage in Cineform chroma keys better than it does in the native format. That isn't the most important thing in chroma keying though. The most important thing is lighting your subject and the screen properly. What you want to do is put your subject a ways in front of the screen so that there are no shadows on the screen. You want to light up the screen evenly so that there isn't multiple shades of green (or blue) which will drive you nuts when you go to key out the background. You also want a better chroma keyer than the one comes with your editor. I use the one the comes with New Blue Video Essentials II. The one that comes with my editor (Sony Vegas) doesn't have the all important spill suppression. I also have Boris FX which has a pretty good keyer as well, though I prefer the New Blue one most of the time. Bad chroma keying looks like a low budget effect. Good keying makes for a composite image that looks the subject is in the new background.

March 16th, 2010, 04:33 PM	#5
Kristian Tigersjäl Tourist Join Date: Mar 2010 Location: Örebro, Sweden Posts: 3	Thanks for the advice. I've heard the built in keyer isn't very good so I'm going to look at alternatives and see if THIS together with a properly lit screen will work any wonders for my "consumer" camera. I did some minor tests already that wasn't very well lit so I can't say much about it, it was also shot in VGA resolution that I'm sure didn't help things. A new test with good light and 720P and I'll give it another go. Yes, the spill was something I noticed because even when I managed to key out most of the blue area I still had small blobs of spill here and there that made a so-so key look plain horrible. It's kind of amazing how different the words are about this. Some people laugh at it saying don't even bother, other say it is possible and can get quite good with the right light.

March 16th, 2010, 08:49 PM	#6
Laurence Kingston Major Player Join Date: Aug 2004 Location: Clermont, FL. Posts: 941	Well I for one love the current generation of point and shoot still cameras with HD video modes. Mine is the Canon SX-1 IS, but there are ones from several different manufacturers that are of similar quality. I also have a pretty decent video camera (a Sony HVR-Z7) that I use for work. How do the two cameras compare? Well the Z7 was about six grand and the SX-1 IS was less than 1/10th that, so you would think there would be a huge quality difference. Not really though. Don't get me wrong. I'm not about to sell the Z7. I really love that camera. It records to either tape or flash memory, has phantom powered XLR audio inputs, separate limiters on both channels, rings so you can easily adjust things by feel when you're shooting. It shoots 60i, 30p and 24p (which I don't really like, but a lot of customers ask for). Another really important thing is that you can put the footage right on a timeline without recoding it into an intermediate and still get really good performance. But aside from those advantages, how does the quality compare between the two cameras? Quite frankly, it is hard to tell which is which in a final render. The quality of the point and shoot is excellent. Yeah I need to recode the raw footage into intermediates, and no I can't record audio good enough for an interview, but for whipping around and capturing b-roll, the little point and shoot rocks! The quality is great. I miss the focus, zoom and aperature rings, but hey, my Z7 doesn't automatically recognize and set itself to faces. In the end, footage from both cameras blends nicely on the timeline, and the point and shoot looks very good on the timeline. Is it as good? I would say for the most part yes it is. It is a very good b-roll camera. I like whipping around with the small camera. I can support it steadily on a small tripod and get in and out of busses and taxis easily. I can climb up steps and hills with it much more easily. I can zoom in to 40x and get some really hard to get shots. I can set everything manually with the menus. No it's not quite as fast, but it's a heck of a lot easier than lugging around the heavier gear. I wouldn't apologize for your point and shoot. Yes there are some limitations, but the quality is much better than most people realize.