Pete-Did you get it yet? - Page 5 at DVinfo.net

Go Back   DV Info Net > Canon EOS / MXF / AVCHD / HDV / DV Camera Systems > Canon HDV and DV Camera Systems > Canon XL H Series HDV Camcorders

Canon XL H Series HDV Camcorders
Canon XL H1S (with SDI), Canon XL H1A (without SDI). Also XL H1.


Reply
 
Thread Tools Search this Thread
Old December 16th, 2005, 02:04 PM   #61
Major Player
 
Join Date: Jun 2004
Location: McLean, VA United States
Posts: 749
The comments about chromatic aberration are really bugging me because while I do see the fringing in Pete's images I don't see them in the resolution chart frames I grabbed. There are three of these starting at http://www.pbase.com/agamid/image/53611832 with one each for the 20X HD lens in 60i and 30p modes and one for the 3x in 30f. These confirm that the horizontal resolution of the XL-H1 is about 720 lines though the lens appears to show modulation out to 880 lines (the MC bars are modulated out to swatch 11 (880 lines) but aliasing is apparent in swatces 10 and 11. They also show that there is a little loss in resolution in going to 720p but not much and that the 3x lens appears nearly as sharp as the others (against the chart at least - in the real world it looks softer).

Now I do not see chromatic aberration in any of these three. Color errors yes but chromatic aberration no. My reasoning is that were chromatic aberration present the red and blue images would be larger or smaller than the green image and you would therefore see a change in image size in switching between the R,G and B images. I don't see such a change. To look for it I concentrated on the white ring which bounds the inner portion of the chart. I don't see any color fringing around this ring either. Does anyone else?
A. J. deLange is offline   Reply With Quote
Old December 16th, 2005, 04:32 PM   #62
Major Player
 
Join Date: Sep 2002
Location: US & THEM
Posts: 827
Quote:
Originally Posted by A. J. deLange
++++. Does anyone else?

I would agree with you that your tests in addition to Pete's tests show little Chromatic Aberration.

The blue and red ghosting that I saw in Pete's tests also manefest in your tests; to a different degree but then again the chart and exposure settings are different.

While the images from the H1 are generally good I am trying to discover the conditions which cause the onset of the blue and red ghosts. At first I thought it an issue related to high contrast but a test performed at a french site goes against this theory cf

http://s56.yousendit.com/d.aspx?id=0...H286MOV9TSB2LQ

here you can see a very strong blue ghost down the left edge of the tower and elsewhere

I wonder whether the flat glass window covering the CCD port has a different coating in the XLHI compared to the XL2 (different reflective colour perhaps?). For sure; some light is bouncing around in there.

If there is an explanation, it will be useful to know so that the onset of ghosting can be avoided
__________________
John Jay

Beware ***PLUGGER-BYTES***
John Jay is offline   Reply With Quote
Old December 16th, 2005, 08:34 PM   #63
Major Player
 
Join Date: Aug 2005
Posts: 119
Hi Pete

It seemed the fairly popular concensus was that the 3x lens was soft until now. I always had trouble with the lens because I found it difficult to check focus with the meager zoom ratio of 3x. Don't get me wrong it's a great lens, and in tight quarters there's nothing I'd rather use except for maybe the mythical 3x manual, but whan you're trying to get focus in a hurry it can be a problem. My question for you is does the HL H1's focus helper function work with the 3x and others or just the stock HD20x lens. Thanks, Jason.
Jason Varner is offline   Reply With Quote
Old December 17th, 2005, 03:54 AM   #64
Major Player
 
Join Date: Nov 2005
Location: Grass Valley, California
Posts: 348
Is it possible that in making the camera PAL and NTSC, that it is mearly a DIP switch that toggles inside the camera housing that is tucked away in a nifty spot? Of course warranty issues would apply, but it's makes you wonder...

BTW I took my Canon L1 apart a couple years back to look at a drum/head issue....it's still in pieces.... So don't try this at home folks!
Now that was a nice lense to work with! (L1) Rack focusing was easier.

larry h.
Larry Huntington is offline   Reply With Quote
Old December 17th, 2005, 07:37 AM   #65
Wrangler
 
Join Date: Oct 2003
Location: DFW area, TX
Posts: 6,108
Images: 1
Quote:
Originally Posted by Larry Huntington
Is it possible that in making the camera PAL and NTSC, that it is mearly a DIP switch that toggles inside the camera housing that is tucked away in a nifty spot? Of course warranty issues would apply, but it's makes you wonder...

BTW I took my Canon L1 apart a couple years back to look at a drum/head issue....it's still in pieces.... So don't try this at home folks!
Now that was a nice lense to work with! (L1) Rack focusing was easier.

larry h.
In this day and age, dipswitches are becoming rare. Most changes now get done by flashing the eeprom with new firmware. I suspect, but don't know for certain that this is the case with adding the PAL functionality to the H1.

-gb-
Greg Boston is offline   Reply With Quote
Old December 17th, 2005, 08:38 AM   #66
Major Player
 
Join Date: Jun 2004
Location: McLean, VA United States
Posts: 749
In an attempt to get a better handle on what is causing some of these color artifacts I thought I'd take the lens out of the equation and focus (interesting concept with no lens) on the electronics. In SD some color artifacting of the sort I think I'm seeing was created by the fact that color matrixing is done after gamma correction. This causes some crosstalk between luma and chroma signals i.e. changes in brightness in the scene can be reflected as changes in color (which is what I think I'm seeing in my Putora chart samples) and vice versa. The most familiar expression of this phenomenon is the dark band between the green and magenta bars in the SMPTE test pattern. To see if HD exhibits this phenomenon as well I grabbed the bars from the XL-H1. It's posted at http://www.pbase.com/image/53638038. Gross examination of it is sufficient to show that the green-magenta thing is there but blowing it up to the point where you can clearly see individual pixels along the borders of bars/patches is also revealing. Besides the gamma/matrix phenomenon we all have to keep in mind that the color information is subsampled 4:1 which means that while a brightness transition ought to be 2-4 pixels wide a color transition could take 8 or more. Keeping this in mind have a look at the bar pattern. Converting it to Lab and looking at the brightness and color channels separately is instructive. See if you think the color artifacts we've been discussing might be caused by the electronics rather than the lens.
A. J. deLange is offline   Reply With Quote
Old December 17th, 2005, 10:25 AM   #67
Major Player
 
Join Date: Jun 2004
Location: McLean, VA United States
Posts: 749
In selling electronics with optional features it is common practice to manufacture only one flavor of the device which contains all the features but to disable the features the customer did not order. If the customer later decides he wants those features they can be enabled often by going to a menu and entering an enabling code supplied by the manufacturer. Other schemes involve changing parameters within the device using special software available only to the manufacturer or authorized dealers/repair stations or, as others have suggested, a new firmware or FPGA download. I'd guess that it is the second method (interaction with the existing firmware) that is involved here. I'd be surprised if it were necessary to actually replace any hardware bits but this is all speculation. I remember a network analyzer where one had to remove the cover, set a dipswitch to "maintenance mode" which enabled new menus and then enter a code in the proper menu from the front panel. The fact that the XLH1 has to go back to the factory for this upgrade implies something like that though it may just be that they are being especially careful to keep the software they are using (if that's their method) safely in house and out of the hands of scoundrels like us.
A. J. deLange is offline   Reply With Quote
Old December 17th, 2005, 12:28 PM   #68
Major Player
 
Join Date: Sep 2002
Location: US & THEM
Posts: 827
Quote:
Originally Posted by A. J. deLange
++++. See if you think the color artifacts we've been discussing might be caused by the electronics rather than the lens.

I looked over the case for electronics and I think that the chart shows a small effect but within the bounds of acceptabilty.

The phenomenon is quite clearly radially dependent whereas an electronic induced effect most likely would apply pan-imagewise?

I delved into the issue more deeply and performed a slant edge frequency response on Pete's 60i ISO chart and the result is here

http://s54.yousendit.com/d.aspx?id=2...Z2GW08M4VICK9D

the double peak on the blue channel pretty much tells its own story - there is a reflective ghost - just look at the blue channel in isolation and you can clearly see it.

Question is - where is it coming from?

My best guesses are - insufficient coating on the CCD port glass; absence of coating between the microlens (which is bonded to the CCD) and the prism

I would completely rule out the lens as cause and would say it is confined to a region between the lens mount and the CCD surface

I found some discussion on blue ghost behavior here but the author is just as baffled as I am :(

http://www.sd3.info/pf828/Sony_828_P..._Analysis.html
__________________
John Jay

Beware ***PLUGGER-BYTES***
John Jay is offline   Reply With Quote
Old December 17th, 2005, 02:09 PM   #69
Major Player
 
Join Date: Nov 2005
Location: Grass Valley, California
Posts: 348
Let's hope it's a friendly blue ghost.

lh
Larry Huntington is offline   Reply With Quote
Old December 19th, 2005, 02:15 AM   #70
Major Player
 
Join Date: Nov 2004
Location: Las Vegas, NV., Los Angeles, CA,
Posts: 220
protective filter, it's a protective filter problem, i'd put money on it
__________________
Jon Bickford, Trepany Films
San Pedro, CA
Trephine001@aol.com
Jon Bickford is offline   Reply
Reply

DV Info Net refers all where-to-buy and where-to-rent questions exclusively to these trusted full line dealers and rental houses...

Professional Video
(800) 833-4801
Portland, OR

B&H Photo Video
(866) 521-7381
New York, NY

Z.G.C.
(973) 335-4460
Mountain Lakes, NJ

Abel Cine Tech
(888) 700-4416
N.Y. NY & L.A. CA

Precision Camera
(800) 677-1023
Austin, TX

DV Info Net also encourages you to support local businesses and buy from an authorized dealer in your neighborhood.
  You are here: DV Info Net > Canon EOS / MXF / AVCHD / HDV / DV Camera Systems > Canon HDV and DV Camera Systems > Canon XL H Series HDV Camcorders

Thread Tools Search this Thread
Search this Thread:

Advanced Search

 



Google
 

All times are GMT -6. The time now is 01:57 AM.


DV Info Net -- Real Names, Real People, Real Info!
1998-2017 The Digital Video Information Network