View Full Version : The cost of Hi-Def lenses
Hse Kha November 15th, 2005, 05:35 PM A lot of people here mention the high cost of the XL-H1 due to its Hi-Def Lens. And that pro HD Lenses generally run into the tens of thousands of dollars.
Well my question is why???
Let's compare.
The lens in the XL-H1 is a 20X image stablized able to resolve 1.5 Megapixels (1440x1080) for a 1/3" sensor.
Now take the Canon PowerShot S2 IS Digital Camera. This camera costs under $500, and comes with lens that is 12x and also image stablized and able to resolve 5 Megapixels!!! And the sensor size is bigger too - 1/2.5".
So what's the deal??? Or should I say justification...
Graeme Nattress November 15th, 2005, 05:56 PM Stills camera lenses are easier to make. Bayer pattern means you need less resolution on the lens, larger chips mean bigger pixels means less resolution needed on the lens.
Also, stills camera lenses tend to breathe a lot - this is ok, but not on a video camera.
Graeme
Chris Hurd November 15th, 2005, 10:31 PM Also if you compare the size and weight of the 20x HD lens to the PowerShot lens, there is a tremendous difference in the amount of glass between them... and more glass usually means much more money.
Evan C. King November 16th, 2005, 12:12 AM What if you were to compare the 20X XL2 lens to the 20X H1 lens? What makes the high def glass so insane as to be worth so much more?
A. J. deLange November 16th, 2005, 01:50 PM The H1 lens is operating close to the diffraction limit. This means that higher order aberrations must be better suppressed than in the XL2 lens making the designer's job more difficult and the lens more complex.
Dylan Couper November 22nd, 2005, 07:40 PM It costs more 'cause it is black, and therefore more professional.
:)
Guy Bruner November 22nd, 2005, 09:57 PM It costs more 'cause it is black, and therefore more professional.
:)
AT LAST...a real interpretation! ;-)
Graeme Nattress November 23rd, 2005, 06:50 AM Canon's pro "L" lenses are white though (usually).
Graeme
Bill Pryor November 24th, 2005, 07:45 PM I've read around here, I think, as well as elsewhere that the lenses from an XL1 would not be good enough for the new HDV Canon. Yet in the P2 board, there's an article which states that the Panasonic uses the "same stock Leica" lens as the DVX100 series. How come the old lens is good enough for the Panasonic but not for the Canon?
Graeme Nattress November 24th, 2005, 07:56 PM I'd severely doubt it's the same leica as in the DVX100 - it's a different size for starters.
Graeme
Barry Green November 24th, 2005, 08:28 PM It's not the same at all. Different focal length, different diameter, different zoom range. It's a newly-engineered high-def lens specifically designed for the HVX.
Ray Van Eng November 25th, 2005, 03:58 AM Mass manufacturing is one of the major deciding factors that drives the cost of a lens down. That is why the Canon Powershot lens and the non-removable stock lens that is attched to the Sony FX-1 or Z1 for that matter can be made for so much cheaper. The Pro HD lens is most likely a limited run item. Unless Canon is selling this lens like hotcakes and still not lowering their price after a while, then the buyers have a case to complain.
Nick Hiltgen November 25th, 2005, 11:58 AM SO does that mean if a body only kit is ever released then the cost of the camera will be greatly reduced? Are we talking like 2k? because if that's the case that's a pretty good chunk towards a mini35 or a micro 35 or an agus 35 or whatever.
Bob Fierce November 25th, 2005, 02:42 PM JVC sells their HD100 body only for $800 less than when they sell it with their specially produced Fujinon 1/3" HD lens. So an 1/3" HD lens can be produced relatively cheaply. Of course their wide angle 1/3" replacement lens due out in December is said to be in the $9,000 range, but then wide angle 1/2" lenses are typically this expensive. Fujinon does sell a 1/2" HD lens that fits the HD100 by means of the $1,470 ACM-12 adapter. The S20X6.4 BMD sells for around $10,000, but when you use a 1/2" lens on a 1/3" camera there's about a 1.4 multiplication factor which would give you an effective range of 280X9 on the HD100.
However, the fact that both of JVC's 1/3" lenses are available only from JVC and not Fujinon may be an indication that Fujinon were asked to cut corners to keep prices low and they may not want to take "credit" for the chromatic aberation that some HD100 users have reported.
Hopefully the premium price of the XL H1 will be reflected in a much higher quality 1/3" HD lens compared to the one Fujinon made for the HD100.
Bill Anderson November 26th, 2005, 11:43 AM Hse Kha's question is a very valid one. Lens offerings today, in general, are no better than they were twenty or thirty years ago. Now keep your hair on, I said in general. Technology today allows us to make unsurpassed optics, optics that pinpoint the beginnings of our universe, etc. The heart of the matter seems to lie, not with capability, but with intent, or commerce. Perhaps both. But that does the professional little good. The sharpest lens I currently own, and I'm sure I have ever owned, is fixed to a plastic 2-1/4" format camera(the lens is not plastic) made in the "Soviet Union" and purchased new for 25$ canadian about twenty yrs ago. It beat the hell out of my Hasselblad lenses.
The next best was a Fujinon purchased twenty yrs ago for 8"x10" format.
At that time the Fujinon cost about a fifth of the less sharp Schneiders and Rodenstocks, because the Fujinon didn't come from a place historically known for its optics.
I own a 60$ Takumar-A zoom lens for 35mm format, lots of glass in this fella, and it is every bit as good as the XL series lenses. Breath? Heck yes. Cheaper to make? Absolutely- but the optics are still there. Coupled with a Pentax K1000, the lot cost 160$- and the images I have made with this combo are included in museum collections, okay they weren't purchased because they were sharp but you get my drift. Put a still lens on your XLs and see for yourself. Optics, resolving power, not chip size Vs film size- are what matters.
In the recent past, the best Kodak was willing to do for filmmakers wishing to shoot Black and White motion picture stock was dreadful compared to the choices weekend still photographers had. Even the Kodak developers for motion picture Black and White stock were atrocious. All this in spite of the fact that making a movie cost a little more than shooting Aunt bessie in her new hat. I, among others, naively tried pointing this out to Kodak, and now were doing much the same in the digital realm. But, as an aside, I love the digital realm.
www.williamanderson.ca
A. J. deLange November 27th, 2005, 12:09 PM Bill,
Let's keep in mind that the goal of HD is to approach the quality of 35mm movie film. The movie frame has a diagonal of about 30 mm. The sensor on the XL H1 has a diagonal of about 6 mm. To produce an image of equal quality, thus, the XL H1 lens must have resolution about 5 times better than that of a 35 mm movie lens. As I mentioned in an earlier post this requires reducing aberrations to close to the diffraction limit. To do this in a 20:1 zoom lens for under $10K represents a tremendous engineering accomplishment. Twenty or 30 years ago it would be impossible to design let alone make such a lens. In those days rays were traced a handful a day. With modern computing thousands of rays can be traced per hour. Take a picture with any one of the old lenses you mentioned using fine grain film. Then cut out a 3.6 x 4.8 mm section of one of the negatives and blow it up to 24 x 18 inches (a smallish TV by today's standards) and compare the results to the XL H1 clips which have been posted here. You will find that those old lenses are not as hot as you might have thought. Are they OK for what they were designed for? Yes indeed but the resolution requirements for a lens using a 35 mm or 5 cm "sensor" are not nearly as stringent as those of a lens using a 3.6 x 4.8 mm sensor.
Nate Weaver November 27th, 2005, 01:07 PM A.J. speaks wisdom.
Can you tell us more about raytracing for optics design? I know what raytracing is technically, but I didn't know it was used to model lens designs before production.
Bill Anderson November 27th, 2005, 02:06 PM A.J I think you misunderstand my point. The reference I made about the quality of the still lenses I own(ed) including the fixed lens was to highlight the inequities in price, relative to quality, and not to compare them to today's best optics. But I stand by my zoom lens comparison to the XL series lenses. These price/quality inequities are still prevalent in today's market. Still lenses costing a fraction of "HD" lenses perform as well when attached to a video camera.
"A zoom lens for under 10K represents a tremendous accomplishment"
I couldn't agree more, but just imagine how much greater an accomplishment it must have been to create the 700$ 7megapixel point and shoot that I own, the one that knocks the socks off the 10K "HD" lens!
If you desire to compare the old with the new, I see little point in shooting a portion of film relevant to the sensor area, what you might want to try is fixing both lenses to the digital camera, and compare that way. And that is also what you might want to try with a decent contemporary still lens and an "HD" lens, and consider the price tag. The chromatic aberration on the XL2 stock lens is laughable, at any price. But it's probably no worse than other SD optics. I'm not trying to be antagonistic here, but is this the best they can do, or is it all they're willing to do, or is that our money's worth?
Chris Hurd November 27th, 2005, 02:55 PM Still lenses costing a fraction of "HD" lenses perform as well when attached to a video camera.I'm sorry but no they most certainly do not. How do you record a slow creeping zoom while using a still photo lens on a video camera, where there's no zoom motor at all? How do you get a wide angle shot with a still photo lens on a video camera, when there's at least a 7x field of view magnification? How do you pull focus with a a still photo lens on a video camera, where there's no geared ring for a follow-focus rig? How do you control zoom, focus and iris remotely from the tripod pan handle when a still photo lens lacks the capability for these most basic remote lens controls? And this is just for starters.
There's a tremendous amount of difference between a still photo lens and a video lens, and most of this difference lies in the fact that a video lens is designed for the movement of the lens (focal length plus focal plane and more) while the camera *is recording.* The requirements of a video lens are different from photo, the design is different from photo and certainly the cost to manufacture is different as well. I'm more than a little surprised to find that some people expect that the price of a video lens should match the price of a photo lens... it's an apples to oranges comparison. They are not at all the same thing. The reason for the drastic disparity in pricing should be obvious to those with the most basic understanding of the differences in optical and mechanical requirements for video recording vs. still photography.
A. J. deLange November 27th, 2005, 05:00 PM Nate:
In ray tracing one places a point on the object side of the lens and then models a ray of light leaving that point which strikes the lens at some point on its surface. Considering the curvature of the surface at the point it strikes, the angle at which it strikes and the index of refraction on can calculate how much that ray is bent and thus the angle at which it travels inside this first element of the "lens". I put "lens" in quotes because the first surface the ray encounters is likely to be a coating, not the lens itself but the principles are the same. In any event the refracted ray is extended to the next place where the index of refraction chances such as the surface another coating, the surface of the actual lens, the rear surface of the lens (if there is no coating) etc. The process is repeated for each place where index of refaction changes up to the last coating of the last element of the lens. From that interface the ray is extended to the image plane. Where it intersects is the image of the original point in object space. The process is now repeated for other rays from the same point which strike the lens front element at different places. Were the lens perfect all extensions of rays from the same object point would strike the image plane at the same point. In fact they don't and so the designer makes adjustments to his design to correct the "aberations" to get the tightest grouping he can. It is sort of cut and try but the trying is done in the computer rather than on the optical bench thus saving untold numbers of man hours and wasted material. That this must be done for all apertures and all focal lengths of which the lens is capable AND for all colors of light in the visible spectrum and that these lenses require dozens of surfaces should help you to appreciate the magnitude of the task.
Glenn Chan November 27th, 2005, 06:59 PM It's probably a combination between economics and technical difficulties. If you look at the price of video equipment in general, you pay exponentially more for small increases in quality.
Mass production also makes a difference... look at the low price of 3CCD cameras due to volume. The manufacturers perhaps hold back on a few features to avoid cannibalization of their more expensive product lines. If you compare Avid to Final Cut, they are pretty close in terms of quality. Yet Avid costs a lot more because it has customers willing to pay its price.
HD lenses are also pretty new and the manufacturers are trying to recoup their R&D costs. Or they put out sub-par lenses at a low cost (i.e. low-end Fujinon, Canon zooms, the JVC lens).
A. J. deLange November 27th, 2005, 07:23 PM Bill,
The fact that you consider a $5K HD lens (that's my guess as to what the XL -H1 lens will be worth on the street) an inequity relative to the lens on a $1K point and shoot camera means that you do not value the things the $5K buy and that's OK. These include all the things Chris mentioned and the things I tried to explain as well. I doubt that the point and shoot has AIS or a 20:1 zoom range or coatings of the same quality (if it even has glass elements) or the aperture of the XL lenses or the build quality or the built in neutral density filters or the back focus adjustment. I also doubt very much that the sensor is 1/3". If it were they wouldn't be able to get away with leaving out the stuff that we are forced to pay $5K for. It's pretty clear to me that if Canon could get adequate performance for $500 bucks worth of plastic they would do so and perhaps charge us $1-or $2K for it putting the XL-H1 at a price point where they would sell lots more of them than they are going to at the current price point.
I'm sorry you can't grasp the point of my little gedenken experiment. I actually did it tonight using a scanned 35 mm image and the result was illustrative of the point I am trying to make: the big lens quality requirement driver (ceteris paribus) is the size of the sensor. The smaller it is the tougher the lens designer's job becomes especially if all the goodies Chris mentioned are on there as well.
BTW I do use a 105 mm Micro Nikor with the XL2 (and did so with the XL1s) as well and have certainly been pleased with the results. But this was designed for one thing: sharpness at close range. It does not zoom. It does not have AIS. It does not have a built in relay system. While it may not have the resolution of the XL-H1 lens it certainly does have enough for the XL2. I look forward to trying it on the XL-H1.
One final question and that is with respect to the "laughable chromatic aberation" of the XL2 lens. I spent a fair amount of time this evening looking at XL2 video and I can't find any. I think chromatic aberation looks like color fringing around bright objects. I do see color smear from the chroma subsampling but nothing which would suggest chromatic aberration which should surround objects. The color smears I see are always to the right of the transition to which they are attached. Does anyone else see chromatic aberration? Under what conditions?
Ray Van Eng November 28th, 2005, 03:34 AM Instead of a stock zoom lens that is often cited for poor quality, I wish that the manufacturers would offer a lens that only has a modest zoom range and maybe a small aperture as well so they can be made cheaply and still offers great quality for the user. Something like a 28-105mm zoom for a 35mm still camera (which many professionals realize that that is all they require for something like 85% of their work.). Anyone who wants to have an exotic wide angles zoom or extreme tele would have to pay for it.
Bill Anderson November 28th, 2005, 10:24 AM Chris, no one has suggested a video lens should cost the same as a
a still lens. The last time I shot motion picture film stock, HD, oh, and stills, I had no difficulty discerning between objectives.
This is not an "apples and oranges" scenario, it is an investigation
into the cost/quality ratio of optics for a given purpose, and
even taking into account the obvious unique mechanical functions of a video lens, I still see no reason to shout hallelujah when a lens that can resolve for a "HD" frame costs 15K- nor when lenses touted as the next coming can barely resolve for a 700 or so pixel dimension without showing chromatic aberrations unworthy of the humblest still lens.
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