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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,


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