Just got the Letus Mini... centering question at DVinfo.net

Yang Wen · April 30th, 2008, 06:51 AM

I attached the Letus to my HV30 and once I zoom in to fill the frame with the GG image, I can tell that the GG is not at the center of the frame. The spacing looks fine on the left and right, but it clearly shows more of the bottom of the adapter, as a result, I would need to zoom in much further to get pass the bottom edge of the GG.

Should the GG image be absolutely centered?

Will Schryver · April 30th, 2008, 10:02 AM

Quote:

Originally Posted by Yang Wen

I attached the Letus to my HV30 and once I zoom in to fill the frame with the GG image, I can tell that the GG is not at the center of the frame. The spacing looks fine on the left and right, but it clearly shows more of the bottom of the adapter, as a result, I would need to zoom in much further to get pass the bottom edge of the GG.

Should the GG image be absolutely centered?

This is not unusual. My GG is also slightly off center (to the right) when I attach it to my XH-A1.

The following comes from the Letus FAQ:

Quote:

The frame size in the Letus35 Extreme is 46x30, larger than the 35mm full frame size (36x24), and much larger than 24x18 (academy frame size).

The purpose of 35mm lens adapters are to achieve 35mm film frame size, which is 24x18. The still camera 35mm frame size is 36x24, which is called "full frame". The Letus35 Extreme is at 46x30. This allows a user to zoom in (to compensate for shifted image sensors etc.) and still get a 36x24 "full frame" image. This is still larger than academy frame size of 24x18 which is the size most look to achieve.

With the 46x30 frame size in the Extreme, there is enough extra frame to achieve an academy frame size of 24x18 or even the full frame size of 36x24 even with a shifted image sensor.

Yang Wen · April 30th, 2008, 10:15 AM

Thanks for the info..

This got my thinking.. so the sensor on these cameras are not center to the camera's lens? How then does the lens project a proper image onto the sensor? Are the sensors off-axis by a fixed amount by design so the lens system is designed to compensate for this?

Bob Hart · April 30th, 2008, 10:35 AM

You may find that many camera imagers are not perfectly centered to the lens center axis and that the image center walks horizontally to one side or in a vertical direction or combination of both as the zoom is moved in.

It does not take much pressure on the junction of a camera and a 35mm to deviate the centerline enough to visibly move the image.

April 30th, 2008, 06:51 AM	#1
Yang Wen Major Player Join Date: May 2003 Location: Chicago, IL Posts: 991	Just got the Letus Mini... centering question I attached the Letus to my HV30 and once I zoom in to fill the frame with the GG image, I can tell that the GG is not at the center of the frame. The spacing looks fine on the left and right, but it clearly shows more of the bottom of the adapter, as a result, I would need to zoom in much further to get pass the bottom edge of the GG. Should the GG image be absolutely centered?

April 30th, 2008, 10:35 AM	#4
Bob Hart Inner Circle Join Date: Dec 2003 Location: PERTH. W.A. AUSTRALIA. Posts: 4,476	You may find that many camera imagers are not perfectly centered to the lens center axis and that the image center walks horizontally to one side or in a vertical direction or combination of both as the zoom is moved in. It does not take much pressure on the junction of a camera and a 35mm to deviate the centerline enough to visibly move the image. Last edited by Bob Hart; April 30th, 2008 at 10:36 AM. Reason: error

April 30th, 2008, 10:15 AM	#3
Yang Wen Major Player Join Date: May 2003 Location: Chicago, IL Posts: 991	Thanks for the info.. This got my thinking.. so the sensor on these cameras are not center to the camera's lens? How then does the lens project a proper image onto the sensor? Are the sensors off-axis by a fixed amount by design so the lens system is designed to compensate for this?