iMovie still image size test

iMovie still image size test

I started with a high resolution scan I had shot on 4x5 film several years ago for sharpness testing. It had been scanned on a high-end professional scanner. The file was 5120x3840. I downsized that file in Photoshop (bicubic interpolation) to: 2560x1920, 1280x960, 640x480 and 320x240. I saved these files as JPEG - Quality level 10.

I created a new iMovie 3.0.1 project bringing the five test images into as still images. The Ken Burns Effect was set to Zoom: 5.00 and Duration: 15.00. The iMovie was exported to iDVD 3 and as a QuickTime Full Quality DV file. Note: the test was repeated using iMovie 3.0.3 with the same results and recommendations as the earlier test with iMovie 3.0.1.

Looking at screen grabs of the full images from the DV file, the 5120x3840, 2560x1920, and 1280x960 images were the same quality. The 1280x960 image was very slightly better than 640x480 image. The 640x480 image was slightly better than 320x240 image.

Looking at screen grabs of the 5x zoomed images from the DV file, the 5120x3840, and 2560x1920 images were the same quality. The 2560x1920 image was better than 1280x960 image. The 1280x960 image was much better than 640x480 image. The 640x480 image was very much better than 320x240 image.

[Technical information on the screen grabs: they were saved from QuickTime Pro (Properties>Video Track>High Quality>High Quality Enabled) as TIFF files using Snapz Pro X.]

When I viewed the DVD I had created on a TV set, the quality differences were not as apparent.

Conclusion: When using the Ken Burns Effect at maximum zoom (5.00x), using an original image at least 2560x1920 produced the highest quality zoomed-in image. If you don't intend to use the Zoom Effect, a maximum image size of 1280x960 is sufficient.

Note: all the above sizes are for the NTSC system.

Full image QuickTime DV frames 5.00 Zoom Effect QuickTime DV frames

(320x240 original) (320x240 original)

(640x480 original) (640x480 original)

(1280x960 original) (1280x960 original)

(2560x1920 original) (2560x1920 original)

(5120x3840 original) (5120x3840 original)

Shooting-Digital.com is the companion site for a new book Shooting Digital: Pro Tips for Taking Great Pictures with Your Digital Camera written by Mikkel Aaland. I was the Technical Editor of the book. Shooting-Digital.com is also an educational site devoted to all aspects of digital imaging. Topics include shooting, acquiring, using and sharing digital images. Check it out!

iMovie still image size test

I started with a high resolution scan I had shot on 4x5 film several years ago for sharpness testing. It had been scanned on a high-end professional scanner. The file was 5120x3840. I downsized that file in Photoshop (bicubic interpolation) to: 2560x1920, 1280x960, 640x480 and 320x240. I saved these files as JPEG - Quality level 10. I created a new iMovie 3.0.1 project bringing the five test images into as still images. The Ken Burns Effect was set to Zoom: 5.00 and Duration: 15.00. The iMovie was exported to iDVD 3 and as a QuickTime Full Quality DV file. Note: the test was repeated using iMovie 3.0.3 with the same results and recommendations as the earlier test with iMovie 3.0.1. Looking at screen grabs of the full images from the DV file, the 5120x3840, 2560x1920, and 1280x960 images were the same quality. The 1280x960 image was very slightly better than 640x480 image. The 640x480 image was slightly better than 320x240 image. Looking at screen grabs of the 5x zoomed images from the DV file, the 5120x3840, and 2560x1920 images were the same quality. The 2560x1920 image was better than 1280x960 image. The 1280x960 image was much better than 640x480 image. The 640x480 image was very much better than 320x240 image. [Technical information on the screen grabs: they were saved from QuickTime Pro (Properties>Video Track>High Quality>High Quality Enabled) as TIFF files using Snapz Pro X.] When I viewed the DVD I had created on a TV set, the quality differences were not as apparent. Conclusion: When using the Ken Burns Effect at maximum zoom (5.00x), using an original image at least 2560x1920 produced the highest quality zoomed-in image. If you don't intend to use the Zoom Effect, a maximum image size of 1280x960 is sufficient. Note: all the above sizes are for the NTSC system.

Full image QuickTime DV frames		5.00 Zoom Effect QuickTime DV frames


(320x240 original)		(320x240 original)


(640x480 original)		(640x480 original)


(1280x960 original)		(1280x960 original)


(2560x1920 original)		(2560x1920 original)


(5120x3840 original)		(5120x3840 original)