Zoom Out and Focus problem... at DVinfo.net

Adam Ward · September 3rd, 2007, 02:01 PM

Hey,

Stupid question from a newbie... I've had my A1 since May and love it however, I am a bit frustrated at the moment. I am trying to do a slow zoom out while simultaneously racking the focus from the background to the foreground yet the A1 refuses to respond to the focus ring until I've stopped zooming out. Is there a setting I can change to allow for this? Thanks in advance for your help!

Adam Ward

Bill Pryor · September 3rd, 2007, 04:20 PM

I'm not sure about this but I think I read somewhere you can't shift focus while zooming. However, what you can do is use the auto shift function. Set the in and out focus points, and it'll do it for you at the push of a button.

Mike Teutsch · September 3rd, 2007, 05:04 PM

Zoom control and focus control are controlled by the same servo motor. You can only do one at a time!

Mike

Adam Ward · September 3rd, 2007, 08:33 PM

Thank you guys for your quick responses... As far as the same servo powering both functions, I was afraid of that...

Bill, I'm not sure I know what you're talking about with the auto shift function. The only thing I know of is the "Position Preset" function on the side of the camera that allows you to save a preset zoom placement or focus point. If there's another way, please do educate me! :)

Thanks again, guys!

-A

Bill Pryor · September 3rd, 2007, 08:55 PM

That's what I'm talking about. If you set the in point focus and out point focus, then press the button and zoom, it will shift. Not exactly while zooming, but right at the end of the zoom it should snap in.

Joe Bourguignon · September 4th, 2007, 03:30 PM

Just curious... I don't have my XH-A1 handy to test this, but would zooming out while holding the Auto Focus button down fix this problem? Since you'd only be using one servo motor (the zoom ring), maybe it'd work? Admittedly, the inability of this camera to rack zoom and focus simultaneously is crippling in certain rare but annoying occasions... Cheers,

-joe

Mike Teutsch · September 4th, 2007, 05:29 PM

Quote:

Originally Posted by Joe Bourguignon

Just curious... I don't have my XH-A1 handy to test this, but would zooming out while holding the Auto Focus button down fix this problem? Since you'd only be using one servo motor (the zoom ring), maybe it'd work? Admittedly, the inability of this camera to rack zoom and focus simultaneously is crippling in certain rare but annoying occasions... Cheers,

-joe

Nope! Crippling compared to what?

Mike

Don Palomaki · September 5th, 2007, 06:30 AM

Quote:

Zoom control and focus control are controlled by the same servo motor.

Assuming Canon used a similar lens automation design to that used in the XL1 and GL1, the lens has separate motors for focus and zoom.

Mike Teutsch · September 5th, 2007, 06:35 AM

Quote:

Originally Posted by Don Palomaki

Assuming Canon used a similar lens automation design to that used in the XL1 and GL1, the lens has separate motors for focus and zoom.

The XL1, XL1s, XL2 and even the XLH1 use a single motor for zoom and focus in their auto lenses. Never had a GL1 or GL2, but I think it is the same.

Mike

Don Palomaki · September 5th, 2007, 06:53 AM

Two motors are shown in the service manual for the XL1 standard lens. The limitation on changing focus while zooming may be due to programming of the lens control system to maintain focus while zooming, arguably the more common requirement for this class of camcorder.

Greg Boston · September 5th, 2007, 07:41 AM

Quote:

Originally Posted by Don Palomaki

Two motors are shown in the service manual for the XL1 standard lens. The limitation on changing focus while zooming may be due to programming of the lens control system to maintain focus while zooming, arguably the more common requirement for this class of camcorder.

Interesting Don, because that contradicts what has been the common perception for years with these cameras. Having had the XL1, then a pair of XL2 cameras, I can confirm that you can't do both at the same time. But you're also the first person to ever admit to having their hands on a service manual.

-gb-

Chris Hurd · September 5th, 2007, 07:53 AM

Don has had that XL1 service manual for several years and has referred to it often while assisting fellow DV Info Net members. I'll take his word on just about anything. I guess the "single motor theory" has been a common misconception among our ranks for a long time, and I'm happy that Don has cleared this up for us.

Mike Teutsch · September 5th, 2007, 08:07 AM

That indeed is very interesting! Does this mean that some enterprising individual or second party company could make a modification to the circuitry and or software that would allow us to do both at the same time?

I was unable to find that manual and would love to see it.

Thanks Don

M

Don Palomaki · September 5th, 2007, 09:35 AM

I suspect it would be hard to get anyone to do it (except as a private labor of love), unless Canon agrees to it.

While it would be possible to reverse engineer the firmware, that would be very costly, (and possibly illegal in the USA - Millennium Copyright Act?). And with the firmware reverse engineered, one would then have to have to reprogram it, compile it, and flash the firmware. That would all require intimate knowledge of the camcorder internals, details of any ASICs in the camcorder - all this is generally far more detailed information than is provided in the service manuals. Also, there may be some other choke point on the control system

Give that there is probably a rather limited market for this capability, the cost of the mod from a third party on a commercial (for profit) basis would be likely be prohibitive for all but folks who can afford the XL-H1 with manual lens, in which case, why bother with the little brother camcorder.

September 3rd, 2007, 02:01 PM	#1
Adam Ward New Boot Join Date: Jul 2007 Location: Dickson, TN Posts: 6	Zoom Out and Focus problem... Hey, Stupid question from a newbie... I've had my A1 since May and love it however, I am a bit frustrated at the moment. I am trying to do a slow zoom out while simultaneously racking the focus from the background to the foreground yet the A1 refuses to respond to the focus ring until I've stopped zooming out. Is there a setting I can change to allow for this? Thanks in advance for your help! Adam Ward

September 3rd, 2007, 05:04 PM	#3
Mike Teutsch Inner Circle Join Date: Oct 2004 Location: Port St. Lucie, Florida Posts: 2,614	Zoom control and focus control are controlled by the same servo motor. You can only do one at a time! Mike __________________ Chapter one, line one. The BH.

September 5th, 2007, 06:53 AM	#10
Don Palomaki Wrangler Join Date: Sep 2001 Location: Northern VA Posts: 4,487	Two motors are shown in the service manual for the XL1 standard lens. The limitation on changing focus while zooming may be due to programming of the lens control system to maintain focus while zooming, arguably the more common requirement for this class of camcorder. __________________ dpalomaki@dspalomaki.com

September 5th, 2007, 07:53 AM	#12
Chris Hurd Obstreperous Rex Join Date: Jan 2001 Location: San Marcos, TX Posts: 27,368 Images: 513	Don has had that XL1 service manual for several years and has referred to it often while assisting fellow DV Info Net members. I'll take his word on just about anything. I guess the "single motor theory" has been a common misconception among our ranks for a long time, and I'm happy that Don has cleared this up for us. __________________ CH Search DV Info Net \| 20 years of DVi \| ...Tuesday is Soylent Green Day!

September 5th, 2007, 08:07 AM	#13
Mike Teutsch Inner Circle Join Date: Oct 2004 Location: Port St. Lucie, Florida Posts: 2,614	That indeed is very interesting! Does this mean that some enterprising individual or second party company could make a modification to the circuitry and or software that would allow us to do both at the same time? I was unable to find that manual and would love to see it. Thanks Don M __________________ Chapter one, line one. The BH.

September 3rd, 2007, 04:20 PM	#2
Bill Pryor Contributor Join Date: Jan 2003 Location: Kansas City, MO Posts: 4,449	I'm not sure about this but I think I read somewhere you can't shift focus while zooming. However, what you can do is use the auto shift function. Set the in and out focus points, and it'll do it for you at the push of a button.

September 3rd, 2007, 08:33 PM	#4
Adam Ward New Boot Join Date: Jul 2007 Location: Dickson, TN Posts: 6	Thank you guys for your quick responses... As far as the same servo powering both functions, I was afraid of that... Bill, I'm not sure I know what you're talking about with the auto shift function. The only thing I know of is the "Position Preset" function on the side of the camera that allows you to save a preset zoom placement or focus point. If there's another way, please do educate me! :) Thanks again, guys! -A

September 3rd, 2007, 08:55 PM	#5
Bill Pryor Contributor Join Date: Jan 2003 Location: Kansas City, MO Posts: 4,449	That's what I'm talking about. If you set the in point focus and out point focus, then press the button and zoom, it will shift. Not exactly while zooming, but right at the end of the zoom it should snap in.

September 4th, 2007, 03:30 PM	#6
Joe Bourguignon New Boot Join Date: Jun 2007 Location: Portland, OR Posts: 14	Just curious... I don't have my XH-A1 handy to test this, but would zooming out while holding the Auto Focus button down fix this problem? Since you'd only be using one servo motor (the zoom ring), maybe it'd work? Admittedly, the inability of this camera to rack zoom and focus simultaneously is crippling in certain rare but annoying occasions... Cheers, -joe

September 5th, 2007, 09:35 AM	#14
Don Palomaki Wrangler Join Date: Sep 2001 Location: Northern VA Posts: 4,487	I suspect it would be hard to get anyone to do it (except as a private labor of love), unless Canon agrees to it. While it would be possible to reverse engineer the firmware, that would be very costly, (and possibly illegal in the USA - Millennium Copyright Act?). And with the firmware reverse engineered, one would then have to have to reprogram it, compile it, and flash the firmware. That would all require intimate knowledge of the camcorder internals, details of any ASICs in the camcorder - all this is generally far more detailed information than is provided in the service manuals. Also, there may be some other choke point on the control system Give that there is probably a rather limited market for this capability, the cost of the mod from a third party on a commercial (for profit) basis would be likely be prohibitive for all but folks who can afford the XL-H1 with manual lens, in which case, why bother with the little brother camcorder. __________________ dpalomaki@dspalomaki.com