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defocus material?
Posted by Jeremy Rowell on April 17, 2009 at 4:30 pmI’m looking for some material that I can put up behind an interview subject that will blur or throw the background out of focus without the viewer noticing the material. I was originally thinking of getting a big piece of frosted plexyglass. Is there any such material?
Thanks in advance!
Jeremy
Steve Wargo replied 17 years ago 10 Members · 14 Replies -
14 Replies
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Jay Shelton
April 18, 2009 at 12:05 amI suppose that would work to some degree. I don’t personally have any experience with that method though. You can purchase fairly large pieces of Plexiglas at a local hardware store (I’m not sure if they sell “pre-frosted” or not), but I am pretty sure I have seen some kits that allow you to frost windows (on doors for example).
As another option there are some frost “gels” used for lighting you can purchase by the roll. I believe they are about 4′ wide and you cut the length to suit your purpose.
You can achieve that shallow depth of field by opening your iris on your camera (or stopping it down). The wider the better. If you have too much light on your set you may have to use some filters (in camera if you have them or you can purchase ones that thread onto the lens) to help reduce the amount of light your camera “sees”, or you can throw some diffusion on lights (or if you have dimmer you can obviously use that).
The difficulty of achieving the DoF you are looking for will more or less determined by your camera. It is more difficult to achieve shallow DoF using a 1/3″ chip camera than it is with a 2/3″ camera.
You may already be aware of all the above, so please disregard if you are. Plus, there are many more knowledgeable people than I on this board that may be able to point you in the right direction or explain it better.
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Jeremey @ DI -
John Sharaf
April 18, 2009 at 12:43 amHampshire frost is often used for this purpose on windows, but it only comes in rolls of 3-4′ width. Another idea is “fantasy cloth” which is semi-transparent and available in 10′ widths of many colors. By lighting objects behind you create semi abstract reality.
JS
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Jeremy Rowell
April 18, 2009 at 2:30 amSome good ideas. I thought I saw the product I’m looking for on a show called LA ink. They used it to blur out the back half of a Tattoo parlor.
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Rick Wise
April 18, 2009 at 2:54 amPart of the “trick” to pulling this off is making sure the fuz material itself is not too sharp. I’ve often used a clean, seamless and untorn 6×6 or 8×8 double or single net stretched tight in a frame for the purpose. However, the net has to be soft focus itself or it will show for what it is. You can also make it more opaque by lighting it up, or more transparent by keeping light of off the surface. Some people like to use white bobinette for a similar purpose.
As mentioned, keep the iris as close to wide open, and the lens on the long side.
Rick Wise
director of photography
and custom lighting design
Oakland, CA
https://www.RickWiseDP.com
https://www.recessionvideo.net
https://www.linkedin.com/in/rwise
email: Rick@RickWiseDP.com -
Peter Rummel
April 18, 2009 at 4:49 pmI’ve seen this effect, and I’ve talked with the grip who helped on the shoot. It was a very light diffusion fabric on a frame – what it was she didn’t know. They were in a relatively small space but they were able to get the BG way out of focus. It took quite some time to set up.
They had to pump extra light on the objects on the far side of the screen so they’d show up. And, most importantly, they had to make sure there was no light hitting the camera side of the screen.
When I first saw the effect I would have sworn it was a chroma key. The foreground was so removed from the background that it looked like a composite. If you want a defocus effect why don’t you just use a greenscreen? It would be easier and faster to light, and you can choose the level of BG defocus in post.
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Ben Ferrer
April 18, 2009 at 11:25 pmI’ve used the double net method described by Rick with very good results.
The shoot required a two person interview which forced using a shorter lens length and therefore increasing the depth-of-field. In order to soften the background a bit I placed an 8’x8′ ScrimJim w/ double net about 7′ behind the talent and opened up the iris all the way (of course). Exposure was managed by controlling the lights and slightly faster shutter speed (the lightest ND available was be too strong). Other considerations were to add a bit more light to the background than usual to compensate for the “filtered” background and added an eggcrate to the key to prevent front lighting the net. Using a 2/3″ CCD camera also helped.-Ben
Ben Ferrer
DP – Transvideo Studios
Mountain View, CA -
Matthew Romanis
April 19, 2009 at 1:31 amDepending upon your budget and where you are, you could try a low cost option. Fibreglass fly wire (the kind used in some flyscreens for windows) can help to create the diffuse look you are after. It comes in 1.5m widths by 10m drops. Cut it to size, mount it on a wooden or aluminium frame and place it mid distance in the background so as not to resolve the mesh. As mentioned above, keep ambient light off the side facing camera.
It creates an artefact of “two point source interference patterns” where the mesh creates an interference gate through which the light waves pass to interfere with each other on the other side of the mesh. Because there are lots of intersections in the mesh the interference patterns are overlapped thus creating a soft focus effect. The thicker the mesh the more the effect, but you will start to resolve the mesh above a certain size and focal distance. -
Steve Wargo
April 20, 2009 at 6:14 amHad a shoot last month with Kobe Bryant and the producer wanted the background way out of focus. We were in a hotel suite and we set the camera (Sony EX-1) right next to the bathroom door and put Kobe about 6 feet away on a chair. The wall in the background had pictures on the wall and there was a lamp on a table. We used a painters plastic from a a paint store and hung it, floor to ceiling, just in front of the lamp. It was certainly soft, just like they wanted. A little too soft for my taste but that’s just me.
Steve Wargo
Tempe, Arizona
It’s a dry heat!Sony HDCAM F-900 & HDW-2000/1 deck
5 Final Cut (not quite PRO) systems
Sony HVR-M25 HDV deck
2-Sony EX-1 HD . -
Jeremy Rowell
April 20, 2009 at 3:57 pmGreat ideas guys. Thanks a lot! You gave me some tricks to toy with.
A little more info on what I’m doing. I have a news set, with the newsroom directly behind it. I want to blur out the newsroom a bit… but there is only a matter of feet (maybe 10) between where the talent sits and the first desks of the newsroom. The cameras are locked down (robotic) about 15 feet in front of the talent. Obviously the type of shots dictate I can’t go in to close. It also will be hard to control the light hitting the front of the material, as the news set is pretty much flooded with light.Thanks again for all of the help, you guys are awesome.
Jeremy
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Jeremy Rowell
April 20, 2009 at 4:12 pmHmmmm… this would be cheap enough for me to toy with…. might be too soft though. Did you only use one layer for that shot?
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