Lens at DVinfo.net

Chris C. Corfield · January 23rd, 2006, 09:33 PM

Hello

A general question about lenses for the GL2. Will a 35mm (film) camera lens work on a video (GL2) camera? If so what does it do to the picture when the lense hasto be stepped down (58mm to whatever). The reason I pose this is that I started with a Canon T70 SLR and have a few lenses for it. I tried the search but I could not find a definative answer.

Thanks
Chris

Andrew Todd · January 23rd, 2006, 11:58 PM

chris, you might want to spend a few days searching around in the alternative imaging forum. A 35mm still lens will not work by itself with a digital video camera. what you need is a 35mm adapter. its too much to go into great detail.. youll find everything you need in that forum.. it is extremely addictive once you start testing out these adapters.. basically you'll get the same depth of field as your still camera. the letus is a good priced adapter and there are many other awesome ones out there.

Graham Bernard · January 24th, 2006, 01:31 AM

Simple put:

* 35mm stills lens is designed to be effective on 35mm wide still film - our "capture" chip is 1/4"

* The image out of the "back" of a 35mm lens is only effective when it would have hit the film plane of that 35mm film

* The advent of mini35 devices create a film plane to the rear of these 35mm lenses by intercepting the "image" and creating a "semi" transparent artificial film plane. In this position and using materials - ground glass or beeswax or the transparent & ground clear CD plastic protector from one of those spindle holders ( oh yes, Ben Winter has recently been experimenting with a certain Supermarket's plastic bag ) this film plane is then either spun or vibrated to reduce the effects of grain.

Still with me?

Having your GL2 on the other side of this film plane with the now "in-focus" image apparent on this device, the "camera" is now reduced to the dumb position of purely a means to capturing that which is on this film plane. For the sake of effectiveness, you would not use the zoom on your camera any more neither your focus - these would only initially be used to "setup" this system, and then left alone.

However, you now have extraordinary & greater opportunities to experiment with and capture extremely shallow depth of field from a position within touching/walking distance of your subject.

At present the only way I have found to achieve shallow depth of field is to:

* Open the Iris to max

* Apply ND filters to bring back the exposure

* Stand back and zoom in and refocus on the subject.

This now gives me quite acceptable shallow DoF and often bamboozles my stills camera buddies.

Grazie

Don Palomaki · January 24th, 2006, 05:02 AM

The GL2 has a fixed lens (adjustable, but not interchangable), so there is no way to substitute a 35mm still camera lens for the GL2 lens (short of rebuilding the camcorder).

However, lens attachment adapters/converters, such as close-up adapters and wide angle converters taht screw on like a filter can be used with success.

It is worth noting that there are lens mount adapters that allow use of some 35mm still camera lenses on the Canon XL series.

Keep in mind that the focal length of the lens does not change, so a 50mm "normal" camera lens acts like a telephoto lens on a camcorder with a 1/4" or 1/3" CCD.

Chris C. Corfield · January 24th, 2006, 08:45 PM

Thanks for all your replies. But let me redirect this thread. I understand that there are devices to mount a 35mm lens to a video camcorder. Which I must say are pretty cool, and I would like to delve into it further. But at this current time I don't have the time. My question is a lenses like the one in this link

http://cgi.ebay.com/Canon-Optura-90-...QQcmdZViewItem

the tele that is. What will happen to the picture if I go from a smaller thread size to the 58mm thread size of my GL2? Is it possible to use this solution? I am just looking to increase my zoom range optically instead of digitally.

Thanks again
Chris

Chris Barcellos · January 24th, 2006, 09:58 PM

There are adaptors out there that fit the 58 mm with out need of step down ring. Even the 58 mm teles designed to fit your camera will likely have vingetting at wider angles. I bought the Sony VCL-HG1758 which is supposed to be designed for the VX 2000, and still had vignetting from mid range to wide.

I would expect that to be the same for the GL.

Don Palomaki · January 25th, 2006, 05:48 AM

Judging from the ad and the price point, it is junk as far as use on a GL2 goes, and will not produce good results. (However, it might satisfy the artistic need of some users.) It is not a 35mm still lens. Over the years I have bought similar low priced photo and video items, and invariably been disappointed.

What do you mean by a 35mm lens - Are you speaking about the thread diameter, ot the film size for which the lens was designed.

Andrew Todd · January 25th, 2006, 09:21 AM

one lens you will definately need if you dont already have it is the wd 58. i just sold mine and it was an awesome lens

Chris C. Corfield · January 25th, 2006, 04:30 PM

Yes the one I linked to is a cheap lens. But it is what I mean for a video tele lens. What models are good and what are crap? And yes I do have the WD58-H, it is an awesome lens. Bought a wide angle for cheap and it was well, cheap. Thanks for all your help.

Chris

Don Palomaki · January 25th, 2006, 08:26 PM

Century Precision Optics is a good brand - not cheap.

Graham Bernard · January 26th, 2006, 07:04 AM

Somewhere, out there in WEB-land, IS a great little video showing-off the effect of the 2x Century on an GL2 - pre and post zooming in. It brings to the screen a mountain climber TOTALLY invisible to start with, then using the zoom he appears something like a sixth of the screen height. But then! Then with the Century 2x adaptor he gets to at least a 1/3 of the screen height. Downside is that for the first part of the zoom-in the Century is vignetting. I'd give this space on a wildlife movie!

I don't know how much light is lost.

Grazie

Quinn OConnell · January 26th, 2006, 09:52 AM

GRAZIE - great run down on the 35mm adaptors.. quite impressive - so are you going to get one?

Graham Bernard · January 26th, 2006, 12:39 PM

Quote:

Originally Posted by Quinn OConnell

so are you going to get one?

Yes. However, with these mini35s there is definately a development curve going on. Viz the latest LetusFlip.

Grazie

Keith Wiggers · February 5th, 2006, 09:00 PM

"Then with the Century 2x adaptor he gets to at least a 1/3 of the screen height. Downside is that for the first part of the zoom-in the Century is vignetting. I'd give this space on a wildlife movie!

I don't know how much light is lost.

Grazie"

I use a Century 2X on my GL2 all of the time for wildlife. Century claims there is NO loss of light, and I believe them. It is a great lens. Obviously you need a sturdy tripod. Yes, you do get vignetting until you are zoomed up about half way. That is a bit of a problem, but not too often. You also have to remove it (A snap with the T connection) for real close ups (insects, flowers etc.). Sometimes the cheapest way to go is to get the best the first time. Good luck whichever way you go.

Keith

January 23rd, 2006, 09:33 PM	#1
Chris C. Corfield Regular Crew Join Date: Dec 2005 Location: Canada Posts: 44	Lens Hello A general question about lenses for the GL2. Will a 35mm (film) camera lens work on a video (GL2) camera? If so what does it do to the picture when the lense hasto be stepped down (58mm to whatever). The reason I pose this is that I started with a Canon T70 SLR and have a few lenses for it. I tried the search but I could not find a definative answer. Thanks Chris

January 23rd, 2006, 11:58 PM	#2
Andrew Todd Major Player Join Date: Oct 2005 Location: Saint John, CANADA Posts: 633	chris, you might want to spend a few days searching around in the alternative imaging forum. A 35mm still lens will not work by itself with a digital video camera. what you need is a 35mm adapter. its too much to go into great detail.. youll find everything you need in that forum.. it is extremely addictive once you start testing out these adapters.. basically you'll get the same depth of field as your still camera. the letus is a good priced adapter and there are many other awesome ones out there. __________________ video : xl2 / letus35xl / bogen 503 photo- canon 1dmkII - bronica etrsi

January 24th, 2006, 05:02 AM	#4
Don Palomaki Wrangler Join Date: Sep 2001 Location: Northern VA Posts: 4,487	The GL2 has a fixed lens (adjustable, but not interchangable), so there is no way to substitute a 35mm still camera lens for the GL2 lens (short of rebuilding the camcorder). However, lens attachment adapters/converters, such as close-up adapters and wide angle converters taht screw on like a filter can be used with success. It is worth noting that there are lens mount adapters that allow use of some 35mm still camera lenses on the Canon XL series. Keep in mind that the focal length of the lens does not change, so a 50mm "normal" camera lens acts like a telephoto lens on a camcorder with a 1/4" or 1/3" CCD. __________________ dpalomaki@dspalomaki.com

January 24th, 2006, 09:58 PM	#6
Chris Barcellos Inner Circle Join Date: Nov 2005 Location: Elk Grove CA Posts: 6,838	Go with a 58 mm thread There are adaptors out there that fit the 58 mm with out need of step down ring. Even the 58 mm teles designed to fit your camera will likely have vingetting at wider angles. I bought the Sony VCL-HG1758 which is supposed to be designed for the VX 2000, and still had vignetting from mid range to wide. I would expect that to be the same for the GL. __________________ Chris J. Barcellos

January 25th, 2006, 05:48 AM	#7
Don Palomaki Wrangler Join Date: Sep 2001 Location: Northern VA Posts: 4,487	Judging from the ad and the price point, it is junk as far as use on a GL2 goes, and will not produce good results. (However, it might satisfy the artistic need of some users.) It is not a 35mm still lens. Over the years I have bought similar low priced photo and video items, and invariably been disappointed. What do you mean by a 35mm lens - Are you speaking about the thread diameter, ot the film size for which the lens was designed. __________________ dpalomaki@dspalomaki.com

January 24th, 2006, 01:31 AM	#3
Graham Bernard Old Boot Join Date: Aug 2002 Location: London UK Posts: 3,633	Simple put: * 35mm stills lens is designed to be effective on 35mm wide still film - our "capture" chip is 1/4" * The image out of the "back" of a 35mm lens is only effective when it would have hit the film plane of that 35mm film * The advent of mini35 devices create a film plane to the rear of these 35mm lenses by intercepting the "image" and creating a "semi" transparent artificial film plane. In this position and using materials - ground glass or beeswax or the transparent & ground clear CD plastic protector from one of those spindle holders ( oh yes, Ben Winter has recently been experimenting with a certain Supermarket's plastic bag ) this film plane is then either spun or vibrated to reduce the effects of grain. Still with me? Having your GL2 on the other side of this film plane with the now "in-focus" image apparent on this device, the "camera" is now reduced to the dumb position of purely a means to capturing that which is on this film plane. For the sake of effectiveness, you would not use the zoom on your camera any more neither your focus - these would only initially be used to "setup" this system, and then left alone. However, you now have extraordinary & greater opportunities to experiment with and capture extremely shallow depth of field from a position within touching/walking distance of your subject. At present the only way I have found to achieve shallow depth of field is to: * Open the Iris to max * Apply ND filters to bring back the exposure * Stand back and zoom in and refocus on the subject. This now gives me quite acceptable shallow DoF and often bamboozles my stills camera buddies. Grazie

January 24th, 2006, 08:45 PM	#5
Chris C. Corfield Regular Crew Join Date: Dec 2005 Location: Canada Posts: 44	Thanks for all your replies. But let me redirect this thread. I understand that there are devices to mount a 35mm lens to a video camcorder. Which I must say are pretty cool, and I would like to delve into it further. But at this current time I don't have the time. My question is a lenses like the one in this link http://cgi.ebay.com/Canon-Optura-90-...QQcmdZViewItem the tele that is. What will happen to the picture if I go from a smaller thread size to the 58mm thread size of my GL2? Is it possible to use this solution? I am just looking to increase my zoom range optically instead of digitally. Thanks again Chris

January 25th, 2006, 09:21 AM	#8
Andrew Todd Major Player Join Date: Oct 2005 Location: Saint John, CANADA Posts: 633	one lens you will definately need if you dont already have it is the wd 58. i just sold mine and it was an awesome lens __________________ video : xl2 / letus35xl / bogen 503 photo- canon 1dmkII - bronica etrsi

January 25th, 2006, 04:30 PM	#9
Chris C. Corfield Regular Crew Join Date: Dec 2005 Location: Canada Posts: 44	Yes the one I linked to is a cheap lens. But it is what I mean for a video tele lens. What models are good and what are crap? And yes I do have the WD58-H, it is an awesome lens. Bought a wide angle for cheap and it was well, cheap. Thanks for all your help. Chris

January 25th, 2006, 08:26 PM	#10
Don Palomaki Wrangler Join Date: Sep 2001 Location: Northern VA Posts: 4,487	Century Precision Optics is a good brand - not cheap. __________________ dpalomaki@dspalomaki.com

January 26th, 2006, 07:04 AM	#11
Graham Bernard Old Boot Join Date: Aug 2002 Location: London UK Posts: 3,633	Somewhere, out there in WEB-land, IS a great little video showing-off the effect of the 2x Century on an GL2 - pre and post zooming in. It brings to the screen a mountain climber TOTALLY invisible to start with, then using the zoom he appears something like a sixth of the screen height. But then! Then with the Century 2x adaptor he gets to at least a 1/3 of the screen height. Downside is that for the first part of the zoom-in the Century is vignetting. I'd give this space on a wildlife movie! I don't know how much light is lost. Grazie

January 26th, 2006, 09:52 AM	#12
Quinn OConnell Regular Crew Join Date: Jun 2005 Location: London, UK Posts: 94	GRAZIE - great run down on the 35mm adaptors.. quite impressive - so are you going to get one?

February 5th, 2006, 09:00 PM	#14
Keith Wiggers New Boot Join Date: May 2005 Posts: 11	"Then with the Century 2x adaptor he gets to at least a 1/3 of the screen height. Downside is that for the first part of the zoom-in the Century is vignetting. I'd give this space on a wildlife movie! I don't know how much light is lost. Grazie" I use a Century 2X on my GL2 all of the time for wildlife. Century claims there is NO loss of light, and I believe them. It is a great lens. Obviously you need a sturdy tripod. Yes, you do get vignetting until you are zoomed up about half way. That is a bit of a problem, but not too often. You also have to remove it (A snap with the T connection) for real close ups (insects, flowers etc.). Sometimes the cheapest way to go is to get the best the first time. Good luck whichever way you go. Keith