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-   Canon XL and GL Series DV Camcorders (https://www.dvinfo.net/forum/canon-xl-gl-series-dv-camcorders/)
-   -   New article on Watchdog: Fields of View comparison (https://www.dvinfo.net/forum/canon-xl-gl-series-dv-camcorders/33940-new-article-watchdog-fields-view-comparison.html)

Chris Hurd October 24th, 2004 10:21 PM

New article on Watchdog: Fields of View comparison
 
Just finished up my XL2 Fields of View Comparison. If you've ever wondered how the XL lenses differ from 35mm still photo lenses using the EF adapter, then this is for you.

Nico van Tonder October 24th, 2004 11:02 PM

XL2 Images
 
Chris,

Your images looks very sharply defined even as stills.

As I am a complete newcomer to video and specially the XL2 some concepts about the configuration of the camcorder is a complete mistery to me. The other problem is that English is not my mother tongue and that complicates the matter. Knee, black, etc., etc., it baffles my mind.

Would you mind to reveal your basic settings you configured your camcorder with as well as the frame rate you use.

My tests reveals a almost complete out of focus footage. I am using the normal 20X lens and I am using 50i (PAL) framerate. I am sure something must be wrong.

Nico van Tonder October 24th, 2004 11:06 PM

I would also like to add that I am viewing the tests on my laptop (a Compaq Evo N800w, 32bit screen colours, 1600x1200px)

Chris Hurd October 24th, 2004 11:24 PM

Nico,

Everything was shot in the "A" (auto) mode at 30p. Everything was at the default setting, including the custom presets menu. The smart-resize function I used in Paint Shop Pro helps to sharpen those images as they're made smaller. That really wasn't the point though -- the point of the article is the field of view of a particular lens.

Nico van Tonder October 25th, 2004 12:13 AM

Chris,

Thanks for your reply.

I can assure you that shooting home movies with a dinky toy whatsename camcorder and then move on to the XL2 is quite an experience.

There's a steep learning curve ahead of me. I increased the sharpness of the XL2 and will do some tests today.

That could be one reason for the softness of the images - the other one could be a Kenko UV filter I installed on the lens. I removed that.

Regards

Greg Boston October 25th, 2004 04:38 AM

Hi Chris,

You stated that using the 20x auto lense at full telephoto was with f1.6. Unless I am missing something, I can't get the lense to stay at f1.6 in full telephoto. I presume due to the design of the internal elements. The same is true of the 16x auto on my XL-1.

So, is that your tractor?

regards,

=gb=

Rob Lohman October 25th, 2004 04:40 AM

Thanks for that test Chris! Awesome to see.

Ralph Roberts October 25th, 2004 06:15 AM

Great test and very informative, Chris... thanks!

Also nice tractor. ;-) ... When I was a kid growing up on the farm, we had a Ferguson 20... just a slightly later model that the one you show, but also a nice solid machine.

--Ralph

Chris Hurd October 25th, 2004 06:57 AM

Greg, that f/stop was an error on the page and I've corrected it to read f/3.5. Thanks for pointing that out.


Yi Fong Yu October 25th, 2004 10:18 AM

chris... that was kewl. thx for posting that page up quickly. i think that will resolve a lot of the "which lens should i use" threads =). the 3x certainly is VERY wide. also the variety of the lenses the XL2 can use is very revealing.

Sebastian Jacome October 25th, 2004 12:16 PM

awsome info, there is so much you can say with words. This helped me see what I have to get next, Thanks.

Alexis Vazquez October 25th, 2004 10:04 PM

Chris, Fantastic comparison.
The first image (4:3 ) of 3x wide angle has more brilliant colors, is this just a nature thing (the sun) or did any color correction?

Alexis

Chris Hurd October 25th, 2004 10:09 PM

I just did that one first. As I pointed out, those frames were shot as the sun was going down so the light was changing rapidly.

Don Williamson October 26th, 2004 10:30 AM

Dear Chris,

Thanks so much for your fields of view comparison. Very helpful. I have a question. Using the 3x lens with the XL2, how much of an improvement in sharpness of image do you observe over the 3x on the XL1/S? I am thinking of getting the XL2 body kit to use with my XL1 lenses, including the 3x. The only problem I've had with the 3x on my XL1 has been its softness on wider shots. If 3x images in the 16:9 widescreen mode are considerably sharper with the XL2 that is very good news. What is your experience in this regard?

Gratefully, Don Williamson

Chris Hurd October 26th, 2004 11:23 AM

Hi Don,

In my experience, softness in wide shots is a result of the pixel averaging phenomenon and really has nothing to do with the lens itself. Basically, you have 720 pixels of width to make up an image. In medium to close-up shots this is perfectly adequate. In long shots showing a wide panorama, you still have only 720 pixels with which to assemble all that detail. So of course, long wide shots appear somewhat softer than close-up shots because the same 720 pixels must now build up a much larger area which contains a lot more visual data. Those pixels can only go so far in presenting all of the detail that makes up all that exists within that larger field of view. I can use DV to portray a scene in a room quite well with plenty of sharpness. But I can't make it look as sharp when the camera is pointing at an expansive panorama of, say, a mountain range. And especially not with a wide-angle lens -- but more about that in a bit.

Now in 16:9 mode with the XL2, all it means is that the field of view is a bit wider than 4:3. So yes you have more pixels for width. But they must cover a wider area anyway. So there's no advantage in sharpness there. You're simply getting a wider image than before (if you had more pixels but didn't increase the image width, then you'd see a sharper picture). The pixel averaging phenomenon doesn't go away in native 16:9, but it doesn't get any worse either. It's a wider image but you have more pixels to use in order to make up for that extra width in the image.

This effect is even more prounced in the 3x Wide Angle lens because... well, it's *all* wide angle throughout the zoom range. So therefore pixel averaging is even more pronounced especially in a long shot. Use that lens in a close-up situation and you won't see any softness. But in long shots of course it's always affected by pixel averaging. This is a limitation of the format, not the lens. But a wide-angle lens just brings it out more and makes pixel averaging more obvious.

Don't go by the sharpness of those frames on that page -- as I pointed out above, there is some sharpness gained by the smart-resize function I used when I resampled those images in Paint Shop Pro. Hope this helps,

Don Williamson October 26th, 2004 11:58 AM

Thanks Chris,

Yes, your reply is very helpful. It makes perfect sense to me. One thing I've wondered about, however. When viewing an anamorphic wide screen DVD of a Hollywood movie at 480p on a progressive scan TV, detail in wide shots can appear to be quite good. But you still have 720x480 pixels. Right? I'm wondering what would account for the difference?

One point you might find interesting. I've burned some projects I shot with the XL1 that involved quite a bit of image tweaking (gamma alteration, sharpening, etc.) to DVD and played them back on upscaling TVs. These TVs, which utilize LCD displays, quadruple the number of pixels. To my delight, the results obtained were very good. The Sony upscaling TVs did the best, in terms of freedom from artifacts. On wider shots, the upscaling gave the impression of more detail. Shots which looked a bit crude on a standard interlaced CRT took on a delicate, smoother, more detailed quality. Customers and sales people in the stores where I did my test were quite impressed, since the results looked somewhat better than most standard broadcast fare. So, while I assume you will heartily recommend upgrading to the XL2, I'm not planning on selling my trusty ol' XL1.

Don Williamson

Bill Pryor October 26th, 2004 12:54 PM

Some good comparisons there, Chris. Interesting how much sharper everything is in 16:9. I expected it to be, but didn't think there would be that much difference.
I have one question a bit off this subject, but seeing the 3X lens brought it to mind...I believe I have read that with the 3X you are not able to use the optical stabilization, is that correct ?

Jean-Philippe Archibald October 26th, 2004 01:00 PM

Bill,

there is NO image stabilisation device on the 3X. I beleive that Canon, in order to keep the cost lower (hum... can't imagine waht could be the price if they had included OIS... ) decided not to include OIS, since it is less of a necessity on a wide angle lens.

Chris Hurd October 26th, 2004 01:05 PM

Hi Bill, yes Jean-Philipe is quite right, there is no OIS on the 3x lens and they kept it off to keep the cost down. Figuring it's only a $1200 lens anyway (Bill is from the pro world where video lenses cost *real* money -- $1200 is nothing, or that is, almost nothing in the realm of the big cameras).

Bill Pryor October 26th, 2004 01:11 PM

Unfortunately, most of the wide angle shooting I would do with a smaller camera would be hand held, so that is kind of annoying. Of course, when shooting with a wide angle lens it's fairly easy to hold the camera pretty steady without OIS. I'm still interested in the XL2 for a certain project, mostly because it is the only small camera with 16:9 chips--not counting the FX1, which really isn't quite out there yet, and even if it were available I haven't been able to determine if its 16:9 setup works in DV as well as HDV. You would think it would, but logic doesn't always apply to camera design, I've found.
I guess I'm going to have to go rent an XL2 for a day and check it out in detail.

Yi Fong Yu October 26th, 2004 01:28 PM

good thread guys! we all luv widescreen. i've always thought about the limits of the DV technology (resolution) and how a good lens (such as 3x) resolves only as good as the format. anyway it was a very informative article. that thing is definitely shows advantages of canon's XL series of DV cams!


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