I've read a lot of posts from people with focus problems with the standard XL1S lens. A lot seem to deal with only autofocus hunting, but some seem to indicate that the back focus will eventually go "bad" on all XL1S cams, necessitating a trip to Canon for repair. Is this true? Or is this issue only with the standard ;ens that came with the old XL1?

It was not unusual for early production XL1 models to have poorly set back focus, and some early lenses did have a problem (mine was replaced under warranty). Have not heard much comment with respect to this in late production XL1 or XL1s models.

Back focus setting control for the standard lense is electronic, a value is stored in the internal XL1 memory (set using the RM-95 Adjusting controller). Installing a lens from a different body might result in a less than optimum backfocus setting for that lense-body combination.

Changes to the relative positions of the lens mount and CCD block (e.g., from being dropped, abused) or similar treatment of the lens could also result in a change to the effective backfocus setting.

Backfocus should be checked as part of routine maintenance.

I think a lot of the posts are made by people with limited experience with AF lenses and sensor and/or limited experience focusing. Many of the posts read something like, "I just shot my first (insert favorite avocation . . job, wedding etc.) and all my shots are out of focus." What usually follows is a plea for help in diagnosing their problem. Invariably someone pops up and suggests a back focus issue, remembering the problems with the early XL1.

Except for the early cameras and lenses, all the so-called back focus problems I've seen are actually operator error.

ronluc8667,
I just finished my first project (wedding) that that was done in total manual mode....what a dramatic improvement over previous shoots with various levels of automatic settings. To prepare my son and I for this, I spent an afternoon with the Canon hooked to a monitor and trying different settings and its effect on the overall look. It was well worth the time spent.

Below is my email to Canon Technical Support and their response. Are they right?

Q:
With my XL1s in the Auto recording program and the lens in manual, I can zoom in on an object to get a focus, but when I zoom out focus is lost. Should this be happening?

A:
Thank you for your e-mail inquiry regarding your XL-1s. This is normal. When the manual focus mode is enabled on your camcorder the XL-1s will not achieve focus automatically. When in this mode you may use the focus ring around the lens to refocus when zooming.

Should you require further assistance, please feel free to email us or visit our customer support website.

I don't think they understood your question and were thrown-off by your "Auto" remark.

Put the camera on a tripod. Place the camera in full MANUAL mode, the lens in Manual Focus, zoom in to an object perhaps 10-15 feet away, press the "Push AF" button on the lens to set focus, release it then pull back out. How does focus look now? (Are you jusdging the focus in the color viewfinder, on the b&w viewfinder or on a tv?

I’ve shot several tests using the set up you recommended. I can get a sharp focus when I zoom in, but when I zoom out the focus is lost. I’ve hooked the camera up to a colour monitor and you can easily see the image go soft. When I press the “Push AF” button again the zoomed out image becomes sharp. Any ideas?

Thanks
David

I'm pretty sure that adjusting the back-focus of the lens will require sending the camera and lens to Canon service. To my knowledge the back-focus of the 16x IIS auto lens (I assume that's the lens we're talking about) can only be performed by Canon service.

Instructions on how to set back focus with the autofocus lenses are in the service manual. An RM-95 adjusting controller is required. Net investment on the order of $200 required for these items. Not something for the average user to try becuase a slip of the finger could make things worse. A bit more complex than programming a VCR.

This is the first time I've heard about this back-focus issue. Is it possible that this can happen only sometimes? I know this sounds crazy but it seems to be happening to me randomly. I posted a topic ( in the lens & optics forum) titled, "1.6 extender won't hold focus?" thinking it had something to do with using the extender with different lighting (I think everyone lost interest due to my ignorance). Anyway, maybe I'm not crazy after all and it can even be fixed?
TIA,
Randy

I don't think anyone lost interest, you said it was fixed. However, back focus usually is not an intermittent problem. Once the back focus is out of adjustment, it doesn't fix itself, so the problem should be repeatable. It would be like front end of your car going in and out of alignment. I've never heard of that happening. Try several of the tests we've suggested and see if you can get the problem to occur.

Does Canon check for any back focus problems when you send it for their recommended yearly check-up?

Yes, they give the camera a thorough once over.

Thanks Jeff,
Actually, I didn't mean to imply the problem was fixed, just not noticable outside at that time when I checked it. I subsequently did the suggested test and it did indeed lose focus. It's still under warranty so I suppose I'll be sending it in.
Thanks again everyone,
Randy

Thanks for everyone’s advice. I’ve talked to Canon again and they are going to service the camera. I will let people know how it turns out.

I just sent my XL-1s in for a check up. I was experiencing the same problem. I was also told that the 3ccd chip may be a little out of alienment. I will let you all know what the results are. Bob Safay

In attempting to film a moon-set, my XL1S using standard 16X ISII lens, I find the focus moves in and out. After reading about similar problems I tried turning off the auto-stabilize and auto-focus, but it still happnes. Is it possible my lens is defective? Or is there something I missed to correct this problem.

Thank you in advance for your help.

In what shooting mode were you? If you are in green box easy
shooting you can't turn of those things. Make sure you are in
full manual mode.

Also make sure that you are in Manual Focus mode.

Auto focus may have difficulty finding and holding focus if the lighting level is low, below ~50 lux.

I have read quite a few comments on the auto focus problems of the standard auto focus lense for the XL1S. (16x Zoom XL 5.5-88mm IS II)

Any suggestions for shooting instructional tennis videos from a varying distance of 40 - 50 feet and from 20 -50 feet.

The focus quite often begins to "hunt" right at the critical moment when the player makes his last move toward the ball just prior to contact.

Any suggestions would be greatly appreciated.

Thanks in advance.

AL

Similar requests have been made in the past. Unfortunately some sports activities are not well suited to auto focus. It may take some practice, but you'll have better success in manual focus.

The AF in most, if not all, prosumer cameras is not up to the job of tracking fast motion.

Alan,

The Canon auto lenses have a hard enough time trying to hold focus on a stationary object, much less a fast moving one.

You might consider the 16X manual lens. It makes a world of difference.

RB

Hi all,
been reading for hours now.. but I'm afraid I couldn't find this problem:

I have a XL1, everything manual...

Zoom in on the back focus card. Get focus. Zoom out. The card is still sharp. But if I then put my hand in front of it (a feet or more away from the lens), my fingers are NOT sharp.

So you could say this is a back focus issue, but during the zooming out the chart stayed sharp. Critical focus doesn't seem to work? I used to shoot all the time all zoomed out and everywhere I went it was all sharp. But that was with another XL1..

Also, if I put a little force in my hands I can tell that the lens moves/seems a veeeeery little bit loose in the body. You can see a little bit of silver metal from the lens mount (more on 1 side then on the other side from the connection). Does everybody see a little bit of the mount or is your lens extremely tight to the body?

thanks all,
Mark

Hum... The behavior you are describing seem normal to me. You have focused on an object (in this case the card), zoomed out, and put another object (your hand) nearer your lens. The distance between the two objects explain your focus "problem". This is called the "Depth of field". There is some things you can do to increase the depth of field, like closing a bit more your iris (an higer f number).

Hope this help,

Maybe I told it the wrong way..

I zoom in.. get the focus. Then I zoom out (which on 80% or so goes out of focus and then into focus again btw) and the chart seems sharp. But then.. when I walk towards the chart, it gets out of focus again. Keeping it all zoomed out of course...
I think it's supposed to keep focus walking towards the chart zoomed out, not touching the zoom. I'll try your DOF thery tomorrow when I have a bit more light, but I'm seriously having doubts..

thanks again,
Mark

Are you PHYSICALLY moving the camera after you set the focus?
If so you are also moving the focussed area and you might get
things out of focus if your lens is quite open. The more open the
lens, the less DOF.

BUT, it could be an issue with the lens itself indeed. But I'll leave
that to the lens professionals here on the forum.

Yeah.. moving it physically..
You know like when a presenter of the show you're taping suddenly approaches the camera, or wants to show his teeth or something. Shouldn't be a problem being all zoomed out normally..

Rob do you maybe know a good company in The Netherlands that can have a look at it? Or do you know the Canon repair-price (outside guarantee)..?

thx

Your camera is not broken. Whenever you change the distance between the camera and the subject, the focus will change also. Workarounds are to focus while moving, or to try to increase the depth of field enough.

I'm suspecting it isn't broken either and you are probably just
"seeing" it the wrong way, or we are understanding you wrong.
With that being said, I didn't notice you were from the wetland
as well. If you want we might be able to meet up some place
and I can take a look at your camera? See if I see anything
weird?

Hi Rob,

it would definitely be nice if you could have a look at it. The thing is that in case of shooting with a tv-presenter I always used to set focus on his/her eye, then zoom out and after that everything stayed in focus, even if the presenter comes very close or even walks further away.. I really hope that the cam is ok..

If you like to please email me: marksolleveld@zonnet.nl
I live in Soest by the way..

thx all for your help

Would appreciate some imput.

I have been doing a fashion show for a school past 3yrs, using the XL1s standard lens, and have been really dissapointed in final video as far as the focus hunting.
The models walk down on a runway approx. 50ft long they stop in the middle and at the end, camera is positioned 25ft and 90degrees from the runway at midpoint. lighting of course is not ideal and not very bright at all, need to videotape from start of walk to midpoint then to far end of runway and back to start. Camera constantly hunts, last year I tried to pan very slowly and not zoom did help a little but very frustrating at least. camera is tripod mounted, iam using an 7"external monitor , tried to use lens in manual and push focus button constantly,but how do you pan,view monitor, zoom and push focus at the same time "not doable"
any ideas?

Hello George,
Well you've just discovered how the role of "focus-puller" came to exist in motion picture production. Focusing while keeping pace with framing and motion is a real challenge.

Use of manual focus is essential, especially in dimmer light. (All auto focus mechanisms require a moderate amount of light and contrast to operate well.) Unfortunately, using of the standard 16x lens for manual focus is a challenge because the focus ring is electronic rather than mechanical. This makes repeatable focus moves almost impossible.

I recommend rehearsing, as best as possible, with your focus before the show. You have the advantage of already knowing where the models will move. Have someone follow that same path on tthe stage/runway and rehearse the manual focus motions required to keep them sharp. (That's what's done on film productions.) If at all possible, rent/purchase one of the manual lenses available for the XL1s. These have mechanical focus rings and witness marks. You can use a white pencil to mark your range on the lens barrel.

I also recommend setting your exposure such that your iris is as closed as possible (i.e. maintain a slower shutter speed or even boost gain just a tiny bit). This will create a deeper depth of field and help to keep subjects in better apparent focus.

Good luck.

I do not own a Xl1s (yet). I was playing around with a friends XL1s and noticed that even the slightest touch seemed to send the lens focus off a bit (in manual focus). If I remember correctly, it seemed that even changing the gain settings would change the focus (manual focus). Is this right? Shouldn't the lens hold focus better than that? Does this unit still have back focus issues?

Bill,
In my experience the 16x auto lens will hold focus when the lens is in Manual Focus mode and when the camera is in Manual exposure mode. If the camera is in a program exposure mode, such as Av or Tv the focus may drift as the camera adjusts the free parameters.

All lenses can have back-focus issues. The 16x auto lens reportedly continuously adjusts its own back focus, hence the lack of a manual adjustment such as those found on the 16x and 14x manual lenses. However, as with any other aspect of a gizmo I am sure that this facility can go haywire and require servicing.

We have had many people report focus problems with the 16x auto lens. Most were due to auto-focus matters. Some were due to operator errors. But, like UFO reports, some were inexpicable. Search around here and you'll likely find enough of each to fill your afternoon's reading.

Hi

I use the XL1 in full manual mode (and I am positive it IS in full manual mode!).

If I'm focusing a frame I'll usually zoom all the way in to my subject, focus, then zoom back to ensure a sharp focus.

When I pull back the focus though the whole shot goes in and out of focus like mad.

Is this an issue with my camera (i.e. does it need servicing), or a common general issue?

Thanks in advance!

If the camera's exposure mode is in Manual mode and your manual is in Manual Focus mode, then the chances are that that the lens' back-focus is out of adjustment. If you are using a 16x manual lens (you didn't specify your lens) then follow a standard back-focus adjustment procedure. If you are using the standard 16x auto lens you will have to send the camera and lens to Canon for service. The 16x auto lens has a system that continuously adjusts back-focus but it can go awry.

One maneuver you may want to try before sending the camera for service (if you are using the 16x auto lens) is to unmount the lens, remove the main battery and back-up battery. Wait a moment and reassemble. Then see if this made any improvement. It's a long shot but worth a try.

Yeah it's the standard auto 16x lens. Thanks for the info I bought the xl1 second hand and the guy said it had been serviced by canon last year, which I guess means it wouldn't harm to send it in anyway.

Thanks for the advice. If you could offer any info on the technicalities of this "back focus" it'd be appreciated too!

Cheers.

You might try call canon as ask when it was last serviced. I believe that they do keep records.

Robert,
As you may know, camera lenses are composed of many optical elements arranged serially to perform various refractory gymnastics on light as it passes through the lens assembly. The rear-most element of a zoom lens is responsible for ensuring that the resultant image strikes the objective point (in this case, the prism or CCD block) in focus throughout the focal length range of the zoom lens.

Since this "last word" element can get out of position (millimeters count here) with use (or when the lens is mounted on different cameras) many, probably most, professional zoom lenses feature a device known as a "flange back" that enables the user to make fine ajustments to the position of this element. This adjustment, known as "back focus" adjustment, basically calls for zooming close-in on something, focusing, then pulling wide to check for consistent focus. The flange back is loosened, then rotated ever so slightly to bring the object into crisp focus, then locked. The process is repeated until crisp focus is restored throughout the zoom lens' range.

The XL1 system's 16x auto lens provides no such flange-back facility to enable user back focus adjustment. I suspect that Canon's reasoning was that, with the camera is selling into the relatively unsophisticated consumer and prosumer markets, such a facility might only lead to unnecessary service expenses as users started to tinker with this foreign gizmo.

Gee, reading this made it sound really clinical, eh? Well, I hope this is helpful.

Robert,
I just recalled that Chris Hurd wrote an article on this general subject quite some time ago. You can find it here (http://www.dvinfo.net/canon/articles/article30.php), in the main section of DVInfo. I think you'll find it particularly interesting since it discusses your specific problem.

Wonderful stuff. Thanks ever so much for all your help guys!

Hi;
I have a Canon XL1s camera and used it only once. Every time I zoom-in or zoom-out the picture became out of focuss for one second. I usually record in Auto mode. I hope someone help me with this.

thank you

Focusing will be a bit of an issue until you get used to your camera. Unless you decide to.....

A) purchase the optional monochrome viewfinder

B) purchase a lens that has true focusing capabilities.
(notice the stock lens rotates through and beyond a full 360)

C) Both A and B


I know that sucks to have to do this, but I chose (C) and couldn't be happier.

Chris, can you explain the relation between the focus problems and the monochrome viewfinder, also a little more indepth about the lens.

I'm sure new users will apreciate, me also.
AV

This so called, focus issue, has been covered very heavily here in the past do a search of XL1 and focus, and you find numerous threads. This should help you (http://www.dvinfo.net/conf/search.php?s=&action=showresults&searchid=265096&sortby=lastpost&sortorder=descending) get started

I won't go into technical details but just relate that I had a problem with my XL1s not maintaining proper focus throughout the zoom range.

Despite keeping everything on manual, it would shift its point of focus during a slow zoom-in even though I'd zoomed earlier in to get critical focus.

I finally got the 16x manual lens and focus has stopped being an issue ever since.

And I haven't missed much of the features of the stock 16x lens except for the stock lens' ability to do a slower zoom than the manual 16x.

Dean Sensui
Base Two Productions.

Yes you will need to read some of the threads to resolve your problem. Don't forget that some of the issues may be related to changes in depth-of-field.

The high-resolution viewfinder (monochrome) does not improve focus, BUT, it does make it easier to focus the system.

Thank you all for your quick response. I am sure it will help me a lot and I will let you know of the result as soon as I try all of your suggestions. Once agian thank for your time and it is realy appreciated. I still looking forward to hear more from you.

Edris Kamali

Okay, I've read every thread on focus problems w/ the camera, but I haven't seen this one. PLEASE HELP!

I'm shooting a movie and one of the shots requires my actor to lay still for about 40 minutes while the sun sets behind him (to be played much faster, of course). The camera is immobile and everything is MANUAL (triple checked). Shooting w/ the controversial 16x servo.....

With nobody touching the camera or even thinking about it, the focus COMPLETELY changes from the subject (about three feet away) to the salt on the UV filter (Grrrrr)- AND THEN CHANGES BACK about ten minutes later- AND THEN starts completely freaking out and falls in and out at incredible speeds! WHAT THE HECK IS GOING ON!! My exposure was f/10 @ 250. Camera stabilizer was on, ND filter OFF.

From what I read, this doesn't sound like a backfocus problem????

I come from a background in still photography where manual MEANS MANUAL. This shot takes forever and is hard on everybody- I CAN'T HAVE MY CAMERA FALLING OUT OF FOCUS ON ITS OWN FREE WILL!!!!!

please advise, thank you!


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