2 quick questions at DVinfo.net

Kesha Smyth · October 28th, 2005, 01:56 AM

Hi everyone!
This is my first post here.
I hope that I am not duplicating any previous posts, but somehow the button search was giving me only an error message.
1. What's the point of using Mini35 if gy-hd100u can be used with 1/3" and 1/2" bayonet lenses? And if you use 400-500, e.t.c lenses it should give you pretty cool depth of field, which for me was the whole idea of Mini35.
2. what do you play the .m2t files? I downloaded Microsoft Player 10, but it is not playing it. Do I need a plugin or something?
Thank you.

Robin Hemerik · October 28th, 2005, 02:07 AM

I'm really no expert, but I can think of a few advantages of using cine/35mm lenses prior to the stock lens:
- no/less CA
- sharper, better images (there is a reason these lenses are so expensive)
- no need to use (that mutch) tele

And to play .m2t files, try VLC player. I have tried several other players, but this was the best. I have an Athlon Duron 1300 mhz, a lousy videocard and just 256mb RAM, but .m2t files run smoothly with VLC!
www.videolan.org

Barry Green · October 28th, 2005, 01:37 PM

Quote:

Originally Posted by Kesha Smyth

And if you use 400-500, e.t.c lenses it should give you pretty cool depth of field, which for me was the whole idea of Mini35.

Well, yes, but the field of view remains very narrow, so in order to get a usable composition with that 400 or 500mm lens, you would likely need to have the HD100 about 40 yards away from the subject. Not necessarily practical for all shooting situations.

Bill Pryor · October 28th, 2005, 02:22 PM

Yeah, a 500 mm 35mm lens would be an effective 3500mm (even more, actually) lens on a 1/3" chip camera. The Mini35 adapter "projects" the image onto a 35mm size ground glass, giving you a 35mm size image, in effect, so a 50mm lens gives you a 50mm lens look, with the shallower depths of field you get with a bigger image size. From what I've seen of footage from various adapters, there are limitations to using them, as there are with any sort of lens adapter.

Kesha Smyth · October 28th, 2005, 02:50 PM

Thank you for your replies!
Speaking of depth of field in general, are there lenses that are comperatively wide and still give a shallow depth of field? And what are the major rules to get shallow DOF?
Thank you.

Barry Green · October 28th, 2005, 05:25 PM

Quote:

Originally Posted by Kesha Smyth

are there lenses that are comperatively wide and still give a shallow depth of field?

Well, no, not really -- wide and shallow are pretty much directly opposite. The wider you go, the deeper it is.

Quote:

And what are the major rules to get shallow DOF?

Open the iris as much as you can, shoot with the lens as telephoto as you can get it, and get as close to the subject as you can, and separate the subject away from the background as much as you can.

As far as DOF goes, there are several factors that interact, but these are the general rules:
Closer to subject = shallower DOF, further from subject = deeper DOF
More telephoto = shallower, wider = deeper
More open iris = shallower, stopped-down iris = deeper

Bill Pryor · October 28th, 2005, 05:51 PM

That pretty much says it. I might elaborate a little. The main issue with depth of field is the size of your imaging area. The bigger the negative, or chip, the shallower the depth of field. If you're shooting with a 1/3" chip camera, you will have a deeper depth of field than when shooting with a larger chip camera under the same circumstances.

So, other than spending money on one of those spinning ground glass adapters, there's not much you can do about your chip size.

You can control aperture and distance and focal length.

For the shallowest depth of field, shoot as close to wide open with your lens as you can get. This often involves using the built-in ND filter, as well as adding one to the end of the lens. You can buy ND filters in various levels, so it might be a good idea to have 2 or 3. For instance, say you're shooting at an F3.5 and you lens opens up to an f1.8 at its widest aperture. You flip on your next level of ND and it may be too much. So you go back to where you were and screw on a lesser ND to the end of the lens to get where you want to be. In controlled lighting situations you can do the same thing by moving lights back or adding diffusion gels, whatever it takes to allow you to shoot wide open.

You also need to be as close as you can get to your subject, either through zooming in or physically moving it. And the background needs to be as far away as possible.

Overall, in most cases with a 1/3" chip camera, the only times you will have the background totally out of focus will be on fairly tight shots.

Jiri Bakala · October 28th, 2005, 09:34 PM

There is a great little program for PalmPilot and I think now for a pocket PC as well that calculates DOF and many other things. You can set your lens, focal length, imager size, distances and many other things. Check it out, well worth it:
http://www.davideubank.com/

Bill Pryor · October 30th, 2005, 03:06 PM

Actually, about the wide angle lens question...the wide angle lens can give you a shallow depth of field, but only if you are right at the close end of the focus. Try this...turn on your heaviest ND and/or add one to the lens, so you can shoot at a wide open aperture. Focus the camera as close as it will go. Let's say it focuses down to six inches. If you focus at 6" on, say, a package of gum or something, you'll notice the background, if it's several feet away, will be soft. Of course, the package of gum will just about fill the frame, so in the real world, this isn't of great value. You get the same effect with the zoom, if you back off and zoom in till the gum just about fills the frame, you'll have about the same depth of field as with the wide angle when it's focused as close as possible.

Every shot in a 35mm movie doesn't have shallow depth of field. Mostly the closeups and the tighter medium shots do, and if you watch the wide angle shots, when they're right in the subject's face, there will be a fairly shallow depth of field.

You're fighting the laws of physics when you try to do this with a small chip camera, but if you can light so you can always shoot with your aperture wide open, then you will have a reasonably shallow depth of field in your tight shots, at least enough so the subject "pops" nicely. For wide shots in which you can't get a shallow depth of field but you want the subject to stand out from the background, do it with lighting--let the background go down a couple of stops from the subject.

October 28th, 2005, 01:56 AM	#1
Kesha Smyth Tourist Join Date: Oct 2005 Posts: 3	2 quick questions Hi everyone! This is my first post here. I hope that I am not duplicating any previous posts, but somehow the button search was giving me only an error message. 1. What's the point of using Mini35 if gy-hd100u can be used with 1/3" and 1/2" bayonet lenses? And if you use 400-500, e.t.c lenses it should give you pretty cool depth of field, which for me was the whole idea of Mini35. 2. what do you play the .m2t files? I downloaded Microsoft Player 10, but it is not playing it. Do I need a plugin or something? Thank you.

October 28th, 2005, 09:34 PM	#8
Jiri Bakala Major Player Join Date: Apr 2004 Location: Kelowna BC Canada Posts: 706	pCAM & pCINE There is a great little program for PalmPilot and I think now for a pocket PC as well that calculates DOF and many other things. You can set your lens, focal length, imager size, distances and many other things. Check it out, well worth it: http://www.davideubank.com/ __________________ www.ascentfilms.com

October 28th, 2005, 02:07 AM	#2
Robin Hemerik Regular Crew Join Date: Sep 2005 Location: Melbourne, Australia Posts: 36	I'm really no expert, but I can think of a few advantages of using cine/35mm lenses prior to the stock lens: - no/less CA - sharper, better images (there is a reason these lenses are so expensive) - no need to use (that mutch) tele And to play .m2t files, try VLC player. I have tried several other players, but this was the best. I have an Athlon Duron 1300 mhz, a lousy videocard and just 256mb RAM, but .m2t files run smoothly with VLC! www.videolan.org

October 28th, 2005, 02:22 PM	#4
Bill Pryor Contributor Join Date: Jan 2003 Location: Kansas City, MO Posts: 4,449	Yeah, a 500 mm 35mm lens would be an effective 3500mm (even more, actually) lens on a 1/3" chip camera. The Mini35 adapter "projects" the image onto a 35mm size ground glass, giving you a 35mm size image, in effect, so a 50mm lens gives you a 50mm lens look, with the shallower depths of field you get with a bigger image size. From what I've seen of footage from various adapters, there are limitations to using them, as there are with any sort of lens adapter.

October 28th, 2005, 02:50 PM	#5
Kesha Smyth Tourist Join Date: Oct 2005 Posts: 3	Thank you for your replies! Speaking of depth of field in general, are there lenses that are comperatively wide and still give a shallow depth of field? And what are the major rules to get shallow DOF? Thank you.

October 28th, 2005, 05:51 PM	#7
Bill Pryor Contributor Join Date: Jan 2003 Location: Kansas City, MO Posts: 4,449	That pretty much says it. I might elaborate a little. The main issue with depth of field is the size of your imaging area. The bigger the negative, or chip, the shallower the depth of field. If you're shooting with a 1/3" chip camera, you will have a deeper depth of field than when shooting with a larger chip camera under the same circumstances. So, other than spending money on one of those spinning ground glass adapters, there's not much you can do about your chip size. You can control aperture and distance and focal length. For the shallowest depth of field, shoot as close to wide open with your lens as you can get. This often involves using the built-in ND filter, as well as adding one to the end of the lens. You can buy ND filters in various levels, so it might be a good idea to have 2 or 3. For instance, say you're shooting at an F3.5 and you lens opens up to an f1.8 at its widest aperture. You flip on your next level of ND and it may be too much. So you go back to where you were and screw on a lesser ND to the end of the lens to get where you want to be. In controlled lighting situations you can do the same thing by moving lights back or adding diffusion gels, whatever it takes to allow you to shoot wide open. You also need to be as close as you can get to your subject, either through zooming in or physically moving it. And the background needs to be as far away as possible. Overall, in most cases with a 1/3" chip camera, the only times you will have the background totally out of focus will be on fairly tight shots.

October 30th, 2005, 03:06 PM	#9
Bill Pryor Contributor Join Date: Jan 2003 Location: Kansas City, MO Posts: 4,449	Actually, about the wide angle lens question...the wide angle lens can give you a shallow depth of field, but only if you are right at the close end of the focus. Try this...turn on your heaviest ND and/or add one to the lens, so you can shoot at a wide open aperture. Focus the camera as close as it will go. Let's say it focuses down to six inches. If you focus at 6" on, say, a package of gum or something, you'll notice the background, if it's several feet away, will be soft. Of course, the package of gum will just about fill the frame, so in the real world, this isn't of great value. You get the same effect with the zoom, if you back off and zoom in till the gum just about fills the frame, you'll have about the same depth of field as with the wide angle when it's focused as close as possible. Every shot in a 35mm movie doesn't have shallow depth of field. Mostly the closeups and the tighter medium shots do, and if you watch the wide angle shots, when they're right in the subject's face, there will be a fairly shallow depth of field. You're fighting the laws of physics when you try to do this with a small chip camera, but if you can light so you can always shoot with your aperture wide open, then you will have a reasonably shallow depth of field in your tight shots, at least enough so the subject "pops" nicely. For wide shots in which you can't get a shallow depth of field but you want the subject to stand out from the background, do it with lighting--let the background go down a couple of stops from the subject.