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December 22nd, 2005, 05:15 PM | #31 |
Barry Wan Kenobi
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Your math is a little off. First there are 1440 photosites, not 1920. But more, the 1/3" sensor is nowhere near as big as 8mm, it's more like 5.24 x 2.95. The net result is that in the vertical direction, 1080/2.95 = 366 photosites per millimeter! So yes, the XLH1 (and other 1/3" HD cameras) are far more demanding than other formats are.
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December 22nd, 2005, 05:19 PM | #32 |
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Ron P
A very interesting and educational post. Canon didn't put a lot of quality in the 1.6 and the EF adapter because the resolution isn't required. However, the new EOS extenders(1.4 and 2x) for the DSL and EOS cameras evidently do not degrade the image of the EOS lenses. Which would indicate that it would not be difficult to incorporate that glass in the XL products. I wonder if the new 20X lens is new glass technology or the L series glass. As you say;"Interesting times--" Ron A |
December 22nd, 2005, 05:30 PM | #33 | |
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Once I have the definitive info, I'll update my figures... Edit: Ah, I found something on dpreview that's interesting with this regard: http://www.dpreview.com/learn/?/Glos...r_Sizes_01.htm 'There appears to be no specific mathematical relationship...' - go figure! Cheers, Ron |
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December 22nd, 2005, 05:54 PM | #34 | |
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I hope Canon will introduce an HD EF-adapter for the XL-H1. But then again, they might not, because EF-glass might just not be up to the task. We'll have to see... |
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December 22nd, 2005, 06:15 PM | #35 |
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Ron;
I own the older 1.4 and 2X and there is a definate difference in quality in the 2X. I was told the new doubler was equally as good as the new 1.4 , but maybe I misunderstood. Hopefully Canon will come up with a solution. Maybe, as you say, new glass and they really need more variety of new lenses for the XL H1. We need a 50 - 300 and a 150 - 500 mm lens with all the bells and whistles of the 20X.. Ron |
December 22nd, 2005, 06:48 PM | #36 | |
Barry Wan Kenobi
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I mean, a 2/3" sensor has a width of 1/3" and a height of 1/4"... so how does that become 2/3"? The answer, of course, is that it doesn't. The name "1/3" or "2/3" is in no way related to actual measurements -- rather it refers to how the size of the sensor would relate to the size of an equivalent tube-type camera(!) So a so-called 2/3" sensor is actually more properly referred to as a 2/3"-type sensor, with the "type" implying that it's roughly equivalent to the old 2/3" tube type sensor. Confusing, yes. Absurd, yes. Yet there it is. As for the actual size of the Canon sensor, that was extrapolated from actual measurements of 2/3" sensors. I found actual sizes of 2/3" 4:3 and 1/3" 4:3 sensors, and 2/3" 16:9 sensors, so I calculated the reduction factor from a 2/3" 4:3 to a 1/3" 4:3 and applied that same factor to a 2/3" 16:9 to come to the end guess of 5.24 x 2.95mm. |
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December 22nd, 2005, 06:49 PM | #37 |
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The way I reasoned in another thread on a similar subject is that HD is supposed to give us about the same quality as 35 mm film which has a diagonal of about 30 mm (cine frame). The H1 sensor has a diagonal of about 6 mm so, ceteris paribus, the Canon HD lens has to be 5 times sharper than the 35 mm lens. Lets give credit to Nikon and Canon and say they make 35 mm lenses twice as sharp as they have to be. That means the HD lens still has to be 2.5 times sharper than the 35 mm lens so the 35 mm lens isn't likely to produce an image as sharp as the HD lens.
I tried the 35 mm Nikkor tonight and the result is at http://www.pbase.com/image/53863540. If you compare to the charts shot with the XL-H1 lens (hit previous a couple of times) you'll see that indeed the Nikkor's resolving power isn't quite as great as the XL-H1 lens. Need to try this in the real world to see if the sharpness is acceptable on actual video. Note that I used f/2.8. Using Barry's numbers I calculate the green (light that is - nothing to do with Barry) diffraction limit at f/5.5! This would apply to the HD lens as well and should go on my list of things I don't like about the camera. |
December 22nd, 2005, 06:50 PM | #38 |
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bill: thanks for the heads up...i will try to be more gender-neutral, esp. since my own first name is turkish, and is often hard to read as either male or female (it's female...)
....probably just my wishful thinking that there could be more women who shoot video (especially the kind i most admire....lauri does the most beautiful footage!) |
December 22nd, 2005, 07:07 PM | #39 |
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A.J.;
Much appreciate the tests. Now we're getting down to something tangible. Your real world test are patiently awaited. These tests are going to help determine my purchase decision. Was the Nikon lens you used an ED? |
December 22nd, 2005, 07:31 PM | #40 |
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Ron,
No, don't think so. It's not marked as such and is pretty old. |
December 22nd, 2005, 08:16 PM | #41 |
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A.J.;
There's still hope for us. I am sure the ED or L lenses are sharper, even though the old ones are pretty good. The comparison tests look fairly close,but, as you say, there is a difference.I assume the tests were done at different times and possibly different light conditions. That would affect the outcome also. Thanks for the prompt effort. Shannon Rawls is going to test also, after the holidays. You guys may come up with an answer before we hear from Canon. Ron |
December 22nd, 2005, 08:40 PM | #42 | |
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- ShannonRawls.com
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Shannon W. Rawls ~ Motion Picture Producer & huge advocate of Digital Acquisition. |
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December 22nd, 2005, 09:48 PM | #43 |
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Lenses
As far as I know, all current Canon digital (35mm body) will accept all the family of EOS lenses. All lenses are not the same sharpness, regardless of the brand or even within the same family. Fixed focal length lenses are generally sharper than "zoom" lenses. I have an XL1 and shoot (record onto digital tape) mostly birds for my own enjoyment and an occasional paying assignment. My primary lens is a Nikon 80-400mm coupled with an adapter (no glass) I purchased from SRB Film in the UK. It's a great lens, but gets ever so soft at the high end, so I have to back it off a bit to around 380mm. The sharpest lenses that I own, and also have used for macro work, is a Sigma 400mm APO and an older Tokina 80-200mm. I have even used a Nikon TC14A teleconverter with the Sigma with absolutely no loss in sharpness. Both these lenses are tack sharp. If anyone is interested, contact me and I'll be glad to send them a few video grabs of insects that I got with these lenses. I know people with XL1's that mainly use Canon, Tokina, or Nikon, and tell me that the Tokina out shines some of their Canon and Nikon lenses, and so on. It all comes down to trying different lenses until you find one that meets your requirements. That's what I had to, and I think that will hold true for the XL H1, regardless of all the techno discussions. Go out and shoot the real world, and then come back and look at it on a good reference monitor. Also, depending on light conditions, I try to keep the lens in the f16 to f8 range at 1/60th second and in manual mode.
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December 23rd, 2005, 03:23 AM | #44 | |
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HTH, Ron Last edited by Ron Pfister; December 23rd, 2005 at 04:04 AM. |
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December 23rd, 2005, 06:53 AM | #45 |
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To all of you who are interested, I just got my XL H1 and will now be able to make tests with the EF-adapter and EF-lenses. I'll post results as soon as possible
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