cheapest way to achieve DOV? at DVinfo.net

Michael Rapadas · October 11th, 2006, 10:58 PM

Quick question (probably a newbie question):
What is the cheapest method of achieving depth of field? I really want that look but I can't afford a mini35 or anything around that price. Is that the only way?

Jarrod Whaley · October 11th, 2006, 11:17 PM

You can get the look of shallow depth of field with any camera that has a zoom lens. If you move the camera back as far you can and zoom in, the magnification will allow you to more selectively apply focus to the frame.

Note that you're not actually decreasing the depth of field with this. In fact you are magnifying what is already there. At a short focal length (zoomed out), the background may look in focus when it is actually not quite there. When the image is magnified by the zoom, the difference is much more apparent.

At any rate, even though the actual depth of field is the same, it looks much shallower this way, and can approximate the results you'd be able to get with a camera that has a larger imaging area. With a 35mm camera, for example, you wouldn't need to zoom in, so you'd be able to have more of the background in the shot than you can get zoomed in with a video camera and still have your subject be the same size. So the larger your camera's chip(s) is/are (or the larger the format of film you're working with), the more background you'll be able to see while still getting the shallow look. It's a perspective thing.

I hope all of that makes sense. DOF is a complicated subject.

Michael Rapadas · October 11th, 2006, 11:19 PM

Quote:

Originally Posted by Jarrod Whaley

You can get the look of shallow depth of field with any camera that has a zoom lens. If you move the camera back as far you can and zoom in, the magnification will allow you to more selectively apply focus to the frame.

Note that you're not actually decreasing the depth of field with this. In fact you are magnifying what is already there. At a short focal length (zoomed out), the background may look in focus when it is actually not quite there. When the image is magnified by the zoom, the difference is much more apparent.

At any rate, even though the actual depth of field is the same, it looks much shallower this way, and can approximate the results you'd be able to get with a camera that has a larger imaging area. With a 35mm camera, for example, you wouldn't need to zoom in, so you'd be able to have more of the background in the shot than you can get zoomed in with a video camera and still have your subject be the same size. So the larger your camera's chip(s) is/are (or the larger the format of film you're working with), the more background you'll be able to see while still getting the shallow look.

I hope all of that makes sense. DOF is a complicated subject.

thanks, yes, I've been doing that for my DOV-trials in my films. To me, it just doesn't cut it. I guess I'll have to start saving. I would rent one, but the cost of it is still too high just for renting. Might as well buy it....

Jon Fairhurst · October 11th, 2006, 11:22 PM

One trick is to use compositing: shoot in focus over a blue/green screen. Shoot your background out of focus. Put them together with chroma key software. Voila!

That said, you will need a clean greenscreen and even lighting for best effect. And you will want some good keying software - or some patience and skill in setting up a key and secondary color correction to fix the fringing.

It's cheaper than a lens converter and lenses. It's magic, in that you can put people in front of the Eiffel Tower or on the moon after filming them in your garage. It's also a pain in the rear end to get everything to look convincing!

Jarrod Whaley · October 11th, 2006, 11:25 PM

Michael--

If you feel like it's a justified expense from your point of view, then I say go for it.

Just remember, too, what I was saying along the lines that a camera with bigger chips will give you much more ability to minimize depth of field. When I went from a camera with 1/4" chips to one with 1/3" chips, I found the difference to be pretty striking given such a seemingly minimal step up in chip size.

I don't know what camera you're using, but you might be able to get closer to the look you want by upgrading to a camera with bigger chips instead of shelling out for a 35mm adapter... and there will be other benefits to upgrading, too. Just a thought.

Jon--

Do you really shoot with a greenscreen that often? You're a braver man than I. I DP'ed on a stop-motion short earlier this year that made extensive use of greenscreen, and by the end of it I was ready to never see the color green again. :) It turned out that everything looked great, but what a headache.

Frank Hool · October 11th, 2006, 11:43 PM

You should check under Alternative Imaging Methods section. There You can find a lot of adapters which are much more affordable than Mini35. Same time most of them generating comparable(or even better) than Mini35. Major difference is maybe image flip and solid camera support accessories.

Richard Zlamany · October 12th, 2006, 12:09 AM

If you open the iris all the way you will have a more shallow DOF.

If the exposure is too bright use a ND filter and higher shutter speeds to correct the exposure.

It works well.

October 11th, 2006, 10:58 PM	#1
Michael Rapadas Regular Crew Join Date: Aug 2006 Location: South San Francisco, CA Posts: 91	cheapest way to achieve DOV? Quick question (probably a newbie question): What is the cheapest method of achieving depth of field? I really want that look but I can't afford a mini35 or anything around that price. Is that the only way?

October 11th, 2006, 11:17 PM	#2
Jarrod Whaley Major Player Join Date: Jun 2006 Location: chattanooga, tn Posts: 721	You can get the look of shallow depth of field with any camera that has a zoom lens. If you move the camera back as far you can and zoom in, the magnification will allow you to more selectively apply focus to the frame. Note that you're not actually decreasing the depth of field with this. In fact you are magnifying what is already there. At a short focal length (zoomed out), the background may look in focus when it is actually not quite there. When the image is magnified by the zoom, the difference is much more apparent. At any rate, even though the actual depth of field is the same, it looks much shallower this way, and can approximate the results you'd be able to get with a camera that has a larger imaging area. With a 35mm camera, for example, you wouldn't need to zoom in, so you'd be able to have more of the background in the shot than you can get zoomed in with a video camera and still have your subject be the same size. So the larger your camera's chip(s) is/are (or the larger the format of film you're working with), the more background you'll be able to see while still getting the shallow look. It's a perspective thing. I hope all of that makes sense. DOF is a complicated subject. __________________ -->jarrod whaley. www.oakstreetfilms.com

October 11th, 2006, 11:22 PM	#4
Jon Fairhurst Inner Circle Join Date: May 2006 Location: Camas, WA, USA Posts: 5,513	One trick is to use compositing: shoot in focus over a blue/green screen. Shoot your background out of focus. Put them together with chroma key software. Voila! That said, you will need a clean greenscreen and even lighting for best effect. And you will want some good keying software - or some patience and skill in setting up a key and secondary color correction to fix the fringing. It's cheaper than a lens converter and lenses. It's magic, in that you can put people in front of the Eiffel Tower or on the moon after filming them in your garage. It's also a pain in the rear end to get everything to look convincing! __________________ Jon Fairhurst

October 11th, 2006, 11:25 PM	#5
Jarrod Whaley Major Player Join Date: Jun 2006 Location: chattanooga, tn Posts: 721	Michael-- If you feel like it's a justified expense from your point of view, then I say go for it. Just remember, too, what I was saying along the lines that a camera with bigger chips will give you much more ability to minimize depth of field. When I went from a camera with 1/4" chips to one with 1/3" chips, I found the difference to be pretty striking given such a seemingly minimal step up in chip size. I don't know what camera you're using, but you might be able to get closer to the look you want by upgrading to a camera with bigger chips instead of shelling out for a 35mm adapter... and there will be other benefits to upgrading, too. Just a thought. Jon-- Do you really shoot with a greenscreen that often? You're a braver man than I. I DP'ed on a stop-motion short earlier this year that made extensive use of greenscreen, and by the end of it I was ready to never see the color green again. :) It turned out that everything looked great, but what a headache. __________________ -->jarrod whaley. www.oakstreetfilms.com

October 11th, 2006, 11:43 PM	#6
Frank Hool Major Player Join Date: Apr 2006 Location: Barca Spain Posts: 384	You should check under Alternative Imaging Methods section. There You can find a lot of adapters which are much more affordable than Mini35. Same time most of them generating comparable(or even better) than Mini35. Major difference is maybe image flip and solid camera support accessories.

October 12th, 2006, 12:09 AM	#7
Richard Zlamany Major Player Join Date: Jun 2005 Location: Hamden CT Posts: 470	If you open the iris all the way you will have a more shallow DOF. If the exposure is too bright use a ND filter and higher shutter speeds to correct the exposure. It works well.