View Full Version : Center Scan vs Full scan test with same framing


Dennis Hingsberg
December 29th, 2013, 09:41 AM
I thought it would make sense to test the Center Scan mode and Full Scan mode on the F55 using the same framing from the two shots to really see what kind of image quality difference there might be between the two modes.

I also didn't want to switch out any lenses in order to get the same framing when switching modes as I did not want any possibility of introducing other variables which could account for image quality differences, so I only used one lens for this test and moved the camera positions in order to get approximately the same framing. I shot all these clips at f8 or higher in order to get a wider depth of field and overall sharper images from the lens.

These video clips are straight out of the camera only transcoded through FCP X in order to create ProRes video files. It is best to download them and view them on your computer. I decided not to upload them to any video sites because the added compression and softening would take away from the differences you would see straight out of camera.

Camera settings: Standard Gamma 5, 500 ISO, 0db gain, 1/48th, 23.98p, 5600k, no ND filters.

Test 1 Clips: Frozen Bush 200MB (ProRes)
(contains 2k center scan mode and full scan mode with same framing)
DOWNLOAD (https://www.dropbox.com/s/n8x7ymvuxkfo3z4/F55_CenterScanTest_Clip1.zip)

Test 2 Clips: Jingle Balls 280MB (ProRes)
(contains 2k center scan mode and full scan mode with same framing)
DOWNLOAD (https://www.dropbox.com/s/44zucq0ydkel6he/F55_CenterScanTest_Clip2.zip)

Conclusions: Center Scan mode is definitely not as sharp as the Full Scan mode, but center scan mode so far does not appear to suffer from any aliasing as we have seen in full scan HFR mode. Two more interesting tests would obviously be center scan HFR mode, and also shooting in 4k full scan mode then cropping out the center in post and comparing the image to the same framing shot in 2k Center Scan mode. More testing to be done.

Tom Roper
December 30th, 2013, 05:51 AM
Thank you Dennis!

Dennis Hingsberg
January 2nd, 2014, 01:49 PM
Your welcome and also I want to clarify that full scan in this test means 2k full scan not 4k full scan. Thus a 2k full scan with super35mm FOV (field of view) is full maintained and then compared against the center scan mode which is a 2k cropped out window from the center of the entire 4k sensor.

Let me know what you guys think of the results.

David Chia
October 31st, 2014, 08:18 AM
It's a good tool to use...

Especially when I have a 50mm on and my producer says, can we do close up now.

Saves time from taking out the matte box , removing the follow focus and changing it into the 105mm and than change it back later