35 mm equivalent for lenses at DVinfo.net

September 17th, 2002, 02:42 PM

I'm doing research on getting video technology for my company over the next 3-6 months and the GL2 is on the short list for the camcorder. I work for a non-profit, performing and educational organization and we will shoot a LOT of live dance/music/theater so the built-in lens' wide angle - and spot-metering - capabilities will be very important. I have searched in vain for 35 mm equivalents for the GL2 (4.2-84 mm - F/1.6-2.9,) and Panasonic AG-DVX100 (4.5-45mm, f1.6) lenses.

Could you experts help me with those specifics?

Don Palomaki · September 17th, 2002, 05:08 PM

Because the aspect ratio of NTSC video (4:3) and 35mm still (3:2) are different, focal lenth equivalents are a bit of a kludge. With that in mind, the GL2 at fullwide is equivalent to a roughly 38 to 40 mm lens on a 35mm still camera. Assuming the same active imaging area on the CCD, the GL1 is perhaps 7% wider than the Panasonic. If the active area is different, you would have to do some field tests to come up with a accurate comparison..

Barry Goyette · September 17th, 2002, 07:11 PM

I think don is pretty much correct as to the wide end of the gl2. The panasonic has larger chips though, and I saw a post on 2-pop (from a panasonic employee) that their lens works out to about a 32mm. Panasonic has chosen to give users a wider zoom, sacrificing most of the longer focal lengths .

The ag-dvx100 really doesn't compete directly with the gl2 (actually it's alone in its class for the most part), It's a very sophisticated camera with a lot more control, and while it looks like the other pro-sumer cameras in a lot of ways, I think panasonic is really targeting it at pros and VERY serious amateurs. It's also at least a grand more.

On the other hand, canon makes an excellent and inexpensive wide angle adapter that will give you about a 28mm

Barry

Jeff Donald · September 18th, 2002, 07:53 AM

The Panasonic DVX100 uses 1/3 inch chips. So, the 7.2 factor still applies (at least for 4:3). The 35mm equivalant is 32mm to 324mm zoom lens. If memory serves me, the factor for 1/4 inch chips is 9.5, so the GL2 35mm equivalant is 40mm to 800mm zoom lens.

Jeff

Chris Hurd · September 18th, 2002, 08:19 AM

Almost dead on, Jeff. According to page 2 of the Canon GL2 brochure (downloadable PDF from www.canondv.com), the 35mm focal length equivalents as stated by Canon are 39.5mm - 790mm. Hope this helps,

Jeff Donald · September 18th, 2002, 08:26 AM

Darn, I hate when I'm off by a half a millimeter. Does this mean I have to turn in my Wrangler hat, Boss?

Jeff

Chris Hurd · September 18th, 2002, 08:54 AM

Boy, don't you know that half a millimeter can mean the very difference between life and death? Don't let it happen again or you'll be diggin' my spurs outta yer hide.

;-)

September 18th, 2002, 09:13 AM

Don't turn the hate on, in, or anywhere! <g>

Sorry, Jeff, I couldn't resist... But hey, thanks so much to you and everyone, this is very helpful.

I must say though that I'm quite disappointed in the actual numbers, and I know my boss will be even more. Although the Panasonic AG-DVX100 comes close, it looks like we couldn't use either cam in the theater (and in many other situations for that matter) without a wide-angle add-on. I could understand why this would be the case on sub $1,000 models such as my Sony D8, but this which comes as a great surprise to me given that we are talking here about "semi-pro" models. [Yes, I know the XL1S would allow us to use different lenses, but that cam didn't make it to our short list for a number of other reasons.]

When I started 35mm photography decades ago, a 50mm lens was considered "standard." That didn't last long as pros and advanced amateurs knew full well that such a lens is unusable in many circumstances (I can still remember incidents where I would trip over things or people, hit walls, etc. while trying to walk backwards to "get more stuff" in my viewfinder.) The 35mmm, then the 28mmm quickly took over as the standard lens for many (If I remember correctly, 28 mmm is roughly the human eyes' "field of vision" and it offers the added benefit of much better depth of field.) Nowadays, even cheap, $350 SLRs routinely come with a 28-80 or 28-105 zoom lens and many pros have their 24mm lens on all the time on at lest one SLR body.

This begs the question: what is the matter with these camcorder manufacturers? A company like Canon makes marvelous lenses for professional photography so there's no doubt on my mind that they CAN put a lens in a GL2 (GL3?) that would be - if I understand the math correctly - say, 3-60mmm. We would gladly pay a couple hundred dollars more for such a useful feature. Wouldn't you?

Jeff Donald · September 18th, 2002, 09:35 AM

Miles,

Unfortunately, the desire for wider focal lengths is limited to a few, enlightened individuals like yourself. The vast majority of camera operators want more telephoto range. Camera manufactures just make what the majority will buy. I would check out Century Precision Optical http://www.centuryoptics.com/ and some of the WA adapters they make. Optical quality is excellent, however the price is a little steep. Canon also makes an adapter for the GL2, as Barry mentions.

Jeff

Barry Goyette · September 18th, 2002, 10:00 AM

Miles

I think jeff is right here, largely the issues are related to marketing. I think also there is an interrelated technical component as well. It's very difficult, albeit, near impossible to create a quality zoom lens that goes from superwide to telephoto. You can see this, as panasonic has given up almost half its potential zoom range to get an extra half millimeter on the wide end. Going even wider would require them to label their zooms as a 3x, or 5x when canon's advertising a 20x on the gl2. I think this is why canon's xl1 system includes an optional 3x lens. While many might think they are just after more of our money, it's probably a more reasonable way to segment the zoom range.

I'm in agreement with you, though, for my use, something in the 28mm-135mm range would be ideal, just like my Eos travel camera. You really should consider the canon wide angle adapter- -it will give you about the same range, it's cheap, and it's a very nice piece of glass. The full size footage I posted with my review was shot with it, and I think it looks plenty sharp.

http://homepage.mac.com/barrygoyette/iMovieTheater7.html
(make sure you download the file to view it at full size.)

Barry

Don Donatello · September 18th, 2002, 06:01 PM

i once thought that perhaps the reason why we are NOT getting wider lens on camcorders is because a WIDE shot shows the weakness of a NTSC image. just can't hold the detail in wide shots.

IMO Tadpole look OK to good on medium and close ups shots BUT on the wide shots !!! forget it ...

Barry Goyette · September 18th, 2002, 06:28 PM

Donatello

I think your point is a good one. Although I don't think the problem you described is specific to use of a wide angle lens as it is to lens-to-subject distance or more correctly "amount of subject in field of view". Using a wide angle close-up of a frosty can of Diet Coke will produce a very sharp image, while using a "normal" length to shoot the crowd and field at the superbowl would produce a fuzzy mess. (this effect can be seen on just about any film or video format...it's just more noticeable on the dv format because it's resolution is lower)

For what it's worth, the higher res chips of the gl2 seem to do a better job on wider shots than other canon dv cams I've used in the past.

Barry

September 19th, 2002, 08:32 AM

>> The vast majority of camera operators want more telephoto range. Camera manufactures just make what the majority will buy.

Jeff, I agree but I would qualify that. From my observations of many industries, manufactures actually make what their (or their hired out) "marketing studies" TELL THEM the majority of people will buy... IMHO that's one of the key reasons the "features" of much of what we buy today are useless or close to unusable.

If we go with the GL2 the Canon WA adapter will be on all the time I'm sure! I think the Century would be a great pick (it looks like it's made by Schneider, a company that has been making lenses on the level of Angenieux or Leica for a long time, I have fond memories of using some of their incredibly sharp lenses in the darkroom, many years ago) but I don't think the company's bean counters would allow that level of expense for just one "accessory."

Barry, thanks so much for the link but I'm on the very slow connection so I'll have to pass on that size download. From what I know of Canon I completely trust that the GL2 + WA is still a very sharp combination. I just wish manufacturers would concentrate their efforts toward the wide angle spectrum versus the "20X" or even the ridiculous "500X" I've seen on some models. Frankly, how much footage (amateur of professional) is shot at full telephoto range, with the exception of very specific applications like wildlife or sports?

Just out of curiosity, is there a place online with perhaps some type of polling where we could express our wishes for such important features?

Don Palomaki · September 20th, 2002, 06:31 AM

> Frankly, how much footage (amateur of professional) is shot at full telephoto range, with the exception of very specific applications like wildlife or sports?

Most folks notice the can't get close enough, thus the demand for telephoto. They do not notice they can't get wide enough unless they are seriously into composition, etc. Thus theconsumer demand.

500x digital zoom - worthless but it sells to the folks who think it will bring in the bikini's at the beach for winter time viewing. Lind of like zero-lux.

September 17th, 2002, 02:42 PM	#1
Miles J. Posts: n/a	35 mm equivalent for lenses I'm doing research on getting video technology for my company over the next 3-6 months and the GL2 is on the short list for the camcorder. I work for a non-profit, performing and educational organization and we will shoot a LOT of live dance/music/theater so the built-in lens' wide angle - and spot-metering - capabilities will be very important. I have searched in vain for 35 mm equivalents for the GL2 (4.2-84 mm - F/1.6-2.9,) and Panasonic AG-DVX100 (4.5-45mm, f1.6) lenses. Could you experts help me with those specifics?

September 18th, 2002, 08:19 AM	#5
Chris Hurd Obstreperous Rex Join Date: Jan 2001 Location: San Marcos, TX Posts: 27,366 Images: 513	Almost dead on, Jeff. According to page 2 of the Canon GL2 brochure (downloadable PDF from www.canondv.com), the 35mm focal length equivalents as stated by Canon are 39.5mm - 790mm. Hope this helps, __________________ CH Search DV Info Net \| 20 years of DVi \| ...Tuesday is Soylent Green Day!

September 18th, 2002, 08:54 AM	#7
Chris Hurd Obstreperous Rex Join Date: Jan 2001 Location: San Marcos, TX Posts: 27,366 Images: 513	Boy, don't you know that half a millimeter can mean the very difference between life and death? Don't let it happen again or you'll be diggin' my spurs outta yer hide. ;-) __________________ CH Search DV Info Net \| 20 years of DVi \| ...Tuesday is Soylent Green Day!

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September 17th, 2002, 05:08 PM	#2
Don Palomaki Wrangler Join Date: Sep 2001 Location: Northern VA Posts: 4,487	Because the aspect ratio of NTSC video (4:3) and 35mm still (3:2) are different, focal lenth equivalents are a bit of a kludge. With that in mind, the GL2 at fullwide is equivalent to a roughly 38 to 40 mm lens on a 35mm still camera. Assuming the same active imaging area on the CCD, the GL1 is perhaps 7% wider than the Panasonic. If the active area is different, you would have to do some field tests to come up with a accurate comparison..

September 17th, 2002, 07:11 PM	#3
Barry Goyette Trustee Join Date: Oct 2001 Location: San Luis Obispo CA Posts: 1,195	I think don is pretty much correct as to the wide end of the gl2. The panasonic has larger chips though, and I saw a post on 2-pop (from a panasonic employee) that their lens works out to about a 32mm. Panasonic has chosen to give users a wider zoom, sacrificing most of the longer focal lengths . The ag-dvx100 really doesn't compete directly with the gl2 (actually it's alone in its class for the most part), It's a very sophisticated camera with a lot more control, and while it looks like the other pro-sumer cameras in a lot of ways, I think panasonic is really targeting it at pros and VERY serious amateurs. It's also at least a grand more. On the other hand, canon makes an excellent and inexpensive wide angle adapter that will give you about a 28mm Barry

September 18th, 2002, 07:53 AM	#4
Jeff Donald Warden Join Date: Mar 2002 Location: Clearwater, FL Posts: 8,287	The Panasonic DVX100 uses 1/3 inch chips. So, the 7.2 factor still applies (at least for 4:3). The 35mm equivalant is 32mm to 324mm zoom lens. If memory serves me, the factor for 1/4 inch chips is 9.5, so the GL2 35mm equivalant is 40mm to 800mm zoom lens. Jeff

September 18th, 2002, 08:26 AM	#6
Jeff Donald Warden Join Date: Mar 2002 Location: Clearwater, FL Posts: 8,287	Darn, I hate when I'm off by a half a millimeter. Does this mean I have to turn in my Wrangler hat, Boss? Jeff

September 18th, 2002, 09:13 AM	#8
Miles J. Posts: n/a	Don't turn the hate on, in, or anywhere! <g> Sorry, Jeff, I couldn't resist... But hey, thanks so much to you and everyone, this is very helpful. I must say though that I'm quite disappointed in the actual numbers, and I know my boss will be even more. Although the Panasonic AG-DVX100 comes close, it looks like we couldn't use either cam in the theater (and in many other situations for that matter) without a wide-angle add-on. I could understand why this would be the case on sub $1,000 models such as my Sony D8, but this which comes as a great surprise to me given that we are talking here about "semi-pro" models. [Yes, I know the XL1S would allow us to use different lenses, but that cam didn't make it to our short list for a number of other reasons.] When I started 35mm photography decades ago, a 50mm lens was considered "standard." That didn't last long as pros and advanced amateurs knew full well that such a lens is unusable in many circumstances (I can still remember incidents where I would trip over things or people, hit walls, etc. while trying to walk backwards to "get more stuff" in my viewfinder.) The 35mmm, then the 28mmm quickly took over as the standard lens for many (If I remember correctly, 28 mmm is roughly the human eyes' "field of vision" and it offers the added benefit of much better depth of field.) Nowadays, even cheap, $350 SLRs routinely come with a 28-80 or 28-105 zoom lens and many pros have their 24mm lens on all the time on at lest one SLR body. This begs the question: what is the matter with these camcorder manufacturers? A company like Canon makes marvelous lenses for professional photography so there's no doubt on my mind that they CAN put a lens in a GL2 (GL3?) that would be - if I understand the math correctly - say, 3-60mmm. We would gladly pay a couple hundred dollars more for such a useful feature. Wouldn't you?

September 18th, 2002, 09:35 AM	#9
Jeff Donald Warden Join Date: Mar 2002 Location: Clearwater, FL Posts: 8,287	Miles, Unfortunately, the desire for wider focal lengths is limited to a few, enlightened individuals like yourself. The vast majority of camera operators want more telephoto range. Camera manufactures just make what the majority will buy. I would check out Century Precision Optical http://www.centuryoptics.com/ and some of the WA adapters they make. Optical quality is excellent, however the price is a little steep. Canon also makes an adapter for the GL2, as Barry mentions. Jeff

September 18th, 2002, 10:00 AM	#10
Barry Goyette Trustee Join Date: Oct 2001 Location: San Luis Obispo CA Posts: 1,195	Miles I think jeff is right here, largely the issues are related to marketing. I think also there is an interrelated technical component as well. It's very difficult, albeit, near impossible to create a quality zoom lens that goes from superwide to telephoto. You can see this, as panasonic has given up almost half its potential zoom range to get an extra half millimeter on the wide end. Going even wider would require them to label their zooms as a 3x, or 5x when canon's advertising a 20x on the gl2. I think this is why canon's xl1 system includes an optional 3x lens. While many might think they are just after more of our money, it's probably a more reasonable way to segment the zoom range. I'm in agreement with you, though, for my use, something in the 28mm-135mm range would be ideal, just like my Eos travel camera. You really should consider the canon wide angle adapter- -it will give you about the same range, it's cheap, and it's a very nice piece of glass. The full size footage I posted with my review was shot with it, and I think it looks plenty sharp. http://homepage.mac.com/barrygoyette/iMovieTheater7.html (make sure you download the file to view it at full size.) Barry

September 18th, 2002, 06:01 PM	#11
Don Donatello Hawaiian Shirt Mogul Join Date: Nov 2001 Location: northern cailfornia Posts: 1,261	i once thought that perhaps the reason why we are NOT getting wider lens on camcorders is because a WIDE shot shows the weakness of a NTSC image. just can't hold the detail in wide shots. IMO Tadpole look OK to good on medium and close ups shots BUT on the wide shots !!! forget it ...

September 18th, 2002, 06:28 PM	#12
Barry Goyette Trustee Join Date: Oct 2001 Location: San Luis Obispo CA Posts: 1,195	Donatello I think your point is a good one. Although I don't think the problem you described is specific to use of a wide angle lens as it is to lens-to-subject distance or more correctly "amount of subject in field of view". Using a wide angle close-up of a frosty can of Diet Coke will produce a very sharp image, while using a "normal" length to shoot the crowd and field at the superbowl would produce a fuzzy mess. (this effect can be seen on just about any film or video format...it's just more noticeable on the dv format because it's resolution is lower) For what it's worth, the higher res chips of the gl2 seem to do a better job on wider shots than other canon dv cams I've used in the past. Barry

September 19th, 2002, 08:32 AM	#13
Miles J. Posts: n/a	>> The vast majority of camera operators want more telephoto range. Camera manufactures just make what the majority will buy. Jeff, I agree but I would qualify that. From my observations of many industries, manufactures actually make what their (or their hired out) "marketing studies" TELL THEM the majority of people will buy... IMHO that's one of the key reasons the "features" of much of what we buy today are useless or close to unusable. If we go with the GL2 the Canon WA adapter will be on all the time I'm sure! I think the Century would be a great pick (it looks like it's made by Schneider, a company that has been making lenses on the level of Angenieux or Leica for a long time, I have fond memories of using some of their incredibly sharp lenses in the darkroom, many years ago) but I don't think the company's bean counters would allow that level of expense for just one "accessory." Barry, thanks so much for the link but I'm on the very slow connection so I'll have to pass on that size download. From what I know of Canon I completely trust that the GL2 + WA is still a very sharp combination. I just wish manufacturers would concentrate their efforts toward the wide angle spectrum versus the "20X" or even the ridiculous "500X" I've seen on some models. Frankly, how much footage (amateur of professional) is shot at full telephoto range, with the exception of very specific applications like wildlife or sports? Just out of curiosity, is there a place online with perhaps some type of polling where we could express our wishes for such important features?

September 20th, 2002, 06:31 AM	#14
Don Palomaki Wrangler Join Date: Sep 2001 Location: Northern VA Posts: 4,487	> Frankly, how much footage (amateur of professional) is shot at full telephoto range, with the exception of very specific applications like wildlife or sports? Most folks notice the can't get close enough, thus the demand for telephoto. They do not notice they can't get wide enough unless they are seriously into composition, etc. Thus theconsumer demand. 500x digital zoom - worthless but it sells to the folks who think it will bring in the bikini's at the beach for winter time viewing. Lind of like zero-lux.