fisheye focusing???? at DVinfo.net

Janson Williams · November 6th, 2008, 04:24 PM

anyone here use the Century Precision Optics 0HD-FEAD-XLH 0.3x Ultra Fisheye Adapter Lens for their A1, i flim some rollerblading and with auto focus and me skating around, it goes in and out of focus some of the times. sometimes i set it to manual focus and leave it at its widest focus and sometimes works and sometimes doesnt

any ideas??

thanks

~pieces

Tom Hardwick · November 6th, 2008, 04:32 PM

Have you left the OIS turned on? Wonder if that could be causing you problems with high g force filming.

Best you lock the focus by aiming the camera combo at about a couple of metres, then dof should cover you from lens slement to infinity at very nearly all apertures.

Janson Williams · November 6th, 2008, 05:01 PM

its on, the symbol with the hand correct?

next time i am out i will turn it off and see if that takes care of the trick

good call

Tripp Woelfel · November 6th, 2008, 06:54 PM

Are you fully zoomed out? Zooming in to any great degree can play havoc with a wide angle adapter. A fisheye might be even more sensitive.

You don't mention if the focus goes in and out when on manual or if it's constantly good or bad. If it doesn't change, I doubt it's the OIS.

Be sure to use peaking and focus assist magnification to set your manual focus. Better yet, set up several focus distances using your HDTV, measuring your critical focus distance. Note the distance in the on screen display. The distance on the display may not be the actual distance. That will help you in the field.

Janson Williams · November 6th, 2008, 07:20 PM

i am zoomed fully out, and i am constantly moving around as i am keeping up with the blader,

on manual it didnt work focusing at the least distance , i really do not know what to set the distance as b/c the distance of the object always varies, i am def going to try turning of the stabilizing and try and different meter lengths to see whats up

Tom Hardwick · November 7th, 2008, 02:32 AM

I'd say leave OIS turn on (the hand symbol) and lock down the focus when you're pointing the camera with attached fisheye at something about 1.5 metres away. I use a very powerful wide-angle too, and doing this means everything's in focus and what's more, stops the auto-focus hunting in poor light.

If you're still getting the focus going in and out then there's something amiss with the camera I'd say.

James R. Leong · November 7th, 2008, 10:31 PM

Try changing your Autofocus mode to NORMAL autofocus instead of INSTANT AF. Normal is Thru the Lens focusing. Page 35 in User Manual. Had similar problem with a regular Century .7 WA adapter. That fixed it.

Janson Williams · November 8th, 2008, 02:41 PM

thanks james, worked perfectly

thank you

November 6th, 2008, 04:24 PM	#1
Janson Williams Regular Crew Join Date: Jul 2008 Location: Pittsburgh, PA Posts: 101	fisheye focusing???? anyone here use the Century Precision Optics 0HD-FEAD-XLH 0.3x Ultra Fisheye Adapter Lens for their A1, i flim some rollerblading and with auto focus and me skating around, it goes in and out of focus some of the times. sometimes i set it to manual focus and leave it at its widest focus and sometimes works and sometimes doesnt any ideas?? thanks ~pieces

November 6th, 2008, 04:32 PM	#2
Tom Hardwick Inner Circle Join Date: Mar 2003 Location: Billericay, England UK Posts: 4,711	Have you left the OIS turned on? Wonder if that could be causing you problems with high g force filming. Best you lock the focus by aiming the camera combo at about a couple of metres, then dof should cover you from lens slement to infinity at very nearly all apertures.

November 6th, 2008, 05:01 PM	#3
Janson Williams Regular Crew Join Date: Jul 2008 Location: Pittsburgh, PA Posts: 101	its on, the symbol with the hand correct? next time i am out i will turn it off and see if that takes care of the trick good call

November 6th, 2008, 06:54 PM	#4
Tripp Woelfel Trustee Join Date: Jan 2008 Location: North Conway, NH Posts: 1,745	Are you fully zoomed out? Zooming in to any great degree can play havoc with a wide angle adapter. A fisheye might be even more sensitive. You don't mention if the focus goes in and out when on manual or if it's constantly good or bad. If it doesn't change, I doubt it's the OIS. Be sure to use peaking and focus assist magnification to set your manual focus. Better yet, set up several focus distances using your HDTV, measuring your critical focus distance. Note the distance in the on screen display. The distance on the display may not be the actual distance. That will help you in the field.

November 6th, 2008, 07:20 PM	#5
Janson Williams Regular Crew Join Date: Jul 2008 Location: Pittsburgh, PA Posts: 101	i am zoomed fully out, and i am constantly moving around as i am keeping up with the blader, on manual it didnt work focusing at the least distance , i really do not know what to set the distance as b/c the distance of the object always varies, i am def going to try turning of the stabilizing and try and different meter lengths to see whats up

November 7th, 2008, 02:32 AM	#6
Tom Hardwick Inner Circle Join Date: Mar 2003 Location: Billericay, England UK Posts: 4,711	I'd say leave OIS turn on (the hand symbol) and lock down the focus when you're pointing the camera with attached fisheye at something about 1.5 metres away. I use a very powerful wide-angle too, and doing this means everything's in focus and what's more, stops the auto-focus hunting in poor light. If you're still getting the focus going in and out then there's something amiss with the camera I'd say.

November 7th, 2008, 10:31 PM	#7
James R. Leong Regular Crew Join Date: May 2004 Location: Vancouver, B.C. Canada Posts: 81	Try changing your Autofocus mode to NORMAL autofocus instead of INSTANT AF. Normal is Thru the Lens focusing. Page 35 in User Manual. Had similar problem with a regular Century .7 WA adapter. That fixed it.

November 8th, 2008, 02:41 PM	#8
Janson Williams Regular Crew Join Date: Jul 2008 Location: Pittsburgh, PA Posts: 101	thanks james, worked perfectly thank you