XL2 Back Focus at DVinfo.net

David Stollak · October 3rd, 2004, 10:53 AM

Hi All,

Just got my new XL2.
I am noticing a back focus problem with the 20X lens and 3X lens.
I taped a newspaper headline accross the room.
I zoom in and focus. When I go wide, its soft and have to rack it into focus. With both lens.
Is there an adjustment on the lens that I dont know about?
Or is it done in camera?
Or is it adjusted by Canon?
Thanks in advance for your help

David

Rob Lohman · October 3rd, 2004, 10:59 AM

Backfocus is not consumer adjustable on those lenses. If it really
is a back focus issue they will need to go to Canon. I would
include the camera as well so they can see/test it.

David Stollak · October 3rd, 2004, 11:16 AM

Is the adjustment done on the lens or on the camera ?

Jeff Donald · October 3rd, 2004, 11:22 AM

The adjustment is done on the lens. But for maximum compatibility it is best to send in the camera and any additional lenses for the camera at the same time.

David Stollak · October 3rd, 2004, 11:25 AM

Thanks so much!

Don Palomaki · October 4th, 2004, 03:48 AM

Can't speak to the XL2, but with the XL1 andn auto lens, back focus adjustment is set electronically with values that are progammed into the body's memory. Thus a back focus issue could be caused by an error/problem in the camcorder with the stored value, the CCD-to-mount distance, the temperature compensation values, or the lens being out of spec.

Thus it is best to return both to have it resolved, and it is always good to send Canon service a complete description of the problem, along with a tape showing the problem

David Stollak · October 4th, 2004, 04:39 PM

Thanks again!

Alfredo Castil · October 7th, 2004, 01:54 PM

I just got my XL2 and the first test I did was the backfocus, I had no troubles. Thanks to all of you to address this problem and hopefully it was fixed in subsequent batches of the XL2

Rob Lohman · October 10th, 2004, 06:54 AM

Alfredo: it is not a "bug" in the system or something. Backfocus
can change due to certain elements like heat/cold etc. and might
require some re-calibration after a while.

David Stollak · October 23rd, 2004, 04:44 PM

Well,

I returned the XL2 and got a new one.
I still have the back focus problem with the 3X lens (manual focus).
I called Canon and they said to send them the camera and the lens, which I did.
They returned it to me saying "Checked back focus on 3X lens,
compared to factory3X, no difference found".

There is a definite problem with manual focus.
Obviously the camera is flawed.

Chris Hurd · October 23rd, 2004, 04:48 PM

Your best bet David is to return the camera and get your money back while you still can. Sounds like you still have a window of opportunity with your dealer there.

Dave Speace · October 26th, 2004, 10:16 AM

Just wanted to say and/or ask if you are focusing by zooming in all the way and pushing the button to focus and then zooming out to check the back focus...? If you are focusing using the focusing ring and then zooming out... it will go soft. Remember to focus using the button! Hope this helps.

tx, Dave

David Stollak · October 26th, 2004, 01:23 PM

Dave,

Thanks for your input,

I am zooming in and focusing using the focus ring, then zooming out. By using the button, are you refering to the AF button on the lens?

Doesn't that defeat the manual focus aspect?

David

Dave Speace · October 26th, 2004, 04:56 PM

Yes... use the button to focus with and see if the camera stays in focus when you zoom out!

Dave

Don Palomaki · October 26th, 2004, 05:58 PM

Try put up a resolution chart to check backfocus. If back focus is OK, the number of lines you can resolve in a picture width should remain about the same regardless of zoom setting. With the 3x telephoto, you may be able to resolve 1" lines at a given distance when at full xzoom. At full wide the lines would have to be 3" wide to appear equally as sharp.

October 3rd, 2004, 10:53 AM	#1
David Stollak New Boot Join Date: Feb 2004 Posts: 12	XL2 Back Focus Hi All, Just got my new XL2. I am noticing a back focus problem with the 20X lens and 3X lens. I taped a newspaper headline accross the room. I zoom in and focus. When I go wide, its soft and have to rack it into focus. With both lens. Is there an adjustment on the lens that I dont know about? Or is it done in camera? Or is it adjusted by Canon? Thanks in advance for your help David

October 3rd, 2004, 10:59 AM	#2
Rob Lohman RED Code Chef Join Date: Oct 2001 Location: Holland Posts: 12,514	Backfocus is not consumer adjustable on those lenses. If it really is a back focus issue they will need to go to Canon. I would include the camera as well so they can see/test it. __________________ Rob Lohman, visuar@iname.com DV Info Wrangler & RED Code Chef Join the DV Challenge \| Lady X Search DVinfo.net for quick answers \| Buy from the best: DVinfo.net sponsors

October 3rd, 2004, 11:22 AM	#4
Jeff Donald Warden Join Date: Mar 2002 Location: Clearwater, FL Posts: 8,287	The adjustment is done on the lens. But for maximum compatibility it is best to send in the camera and any additional lenses for the camera at the same time. __________________ Jeff Donald Carpe Diem Search DVinfo.net for quick answers \| Where to Buy? From the best in the business: DVinfo.net sponsors

October 4th, 2004, 03:48 AM	#6
Don Palomaki Wrangler Join Date: Sep 2001 Location: Northern VA Posts: 4,488	Can't speak to the XL2, but with the XL1 andn auto lens, back focus adjustment is set electronically with values that are progammed into the body's memory. Thus a back focus issue could be caused by an error/problem in the camcorder with the stored value, the CCD-to-mount distance, the temperature compensation values, or the lens being out of spec. Thus it is best to return both to have it resolved, and it is always good to send Canon service a complete description of the problem, along with a tape showing the problem __________________ dpalomaki@dspalomaki.com

October 7th, 2004, 01:54 PM	#8
Alfredo Castil Regular Crew Join Date: Sep 2004 Location: Chicago, IL Posts: 40	I just got my XL2 and the first test I did was the backfocus, I had no troubles. Thanks to all of you to address this problem and hopefully it was fixed in subsequent batches of the XL2 __________________ Ask not whether you can afford to make it, but whether can you afford not to.

October 3rd, 2004, 11:16 AM	#3
David Stollak New Boot Join Date: Feb 2004 Posts: 12	Is the adjustment done on the lens or on the camera ?

October 3rd, 2004, 11:25 AM	#5
David Stollak New Boot Join Date: Feb 2004 Posts: 12	Thanks so much!

October 4th, 2004, 04:39 PM	#7
David Stollak New Boot Join Date: Feb 2004 Posts: 12	Thanks again!

October 10th, 2004, 06:54 AM	#9
Rob Lohman RED Code Chef Join Date: Oct 2001 Location: Holland Posts: 12,514	Alfredo: it is not a "bug" in the system or something. Backfocus can change due to certain elements like heat/cold etc. and might require some re-calibration after a while. __________________ Rob Lohman, visuar@iname.com DV Info Wrangler & RED Code Chef Join the DV Challenge \| Lady X Search DVinfo.net for quick answers \| Buy from the best: DVinfo.net sponsors

October 23rd, 2004, 04:44 PM	#10
David Stollak New Boot Join Date: Feb 2004 Posts: 12	Well, I returned the XL2 and got a new one. I still have the back focus problem with the 3X lens (manual focus). I called Canon and they said to send them the camera and the lens, which I did. They returned it to me saying "Checked back focus on 3X lens, compared to factory3X, no difference found". There is a definite problem with manual focus. Obviously the camera is flawed.

October 23rd, 2004, 04:48 PM	#11
Chris Hurd Obstreperous Rex Join Date: Jan 2001 Location: San Marcos, TX Posts: 27,368 Images: 513	Your best bet David is to return the camera and get your money back while you still can. Sounds like you still have a window of opportunity with your dealer there. __________________ CH Search DV Info Net \| 20 years of DVi \| ...Tuesday is Soylent Green Day!

October 26th, 2004, 10:16 AM	#12
Dave Speace New Boot Join Date: Feb 2004 Location: Morgantown, PA Posts: 9	back focus Just wanted to say and/or ask if you are focusing by zooming in all the way and pushing the button to focus and then zooming out to check the back focus...? If you are focusing using the focusing ring and then zooming out... it will go soft. Remember to focus using the button! Hope this helps. tx, Dave __________________ Dave Speace Producer/Director/DP

October 26th, 2004, 01:23 PM	#13
David Stollak New Boot Join Date: Feb 2004 Posts: 12	Dave, Thanks for your input, I am zooming in and focusing using the focus ring, then zooming out. By using the button, are you refering to the AF button on the lens? Doesn't that defeat the manual focus aspect? David

October 26th, 2004, 04:56 PM	#14
Dave Speace New Boot Join Date: Feb 2004 Location: Morgantown, PA Posts: 9	xl2 focusing Yes... use the button to focus with and see if the camera stays in focus when you zoom out! Dave __________________ Dave Speace Producer/Director/DP

October 26th, 2004, 05:58 PM	#15
Don Palomaki Wrangler Join Date: Sep 2001 Location: Northern VA Posts: 4,488	Try put up a resolution chart to check backfocus. If back focus is OK, the number of lines you can resolve in a picture width should remain about the same regardless of zoom setting. With the 3x telephoto, you may be able to resolve 1" lines at a given distance when at full xzoom. At full wide the lines would have to be 3" wide to appear equally as sharp. __________________ dpalomaki@dspalomaki.com