loss of resolution when importing psd stills

[Steve Roberts]

Your composition’s size is related to the playback device. DVD playback? Hard Drive playback? Read on.

Regarding scanning, here’s a post from a “scanning stills” thread earlier:

The dpi figure is the intermediary between the real world and the digital world. When scanning anything, the higher the dpi, the more pixels will exist in the digital image.

2″x3″ image scanned at 72dpi yields a 144×216 pixel digital image.
2″x3″ image scanned at 300 dpi yields a 600×900 pixel digital image.

Start with your TV frame size. Often 720×540.
Determine how much of each image will fill that frame. If you don’t want to zoom in, then you want to scan your image so it ends up as 720×540. If, however, you want to zoom in so half the image fills the TV frame, scan at a dpi that will give you a digital image which is about twice the size as the TV frame. With a print, you would measure the zoomed-in area in inches, then find a dpi which would give you the TV frame size for that little area. For example:

10″x8″ photo, fill 720×540 frame:
720/10 = 72 dpi, 540/8 = 67.5 dpi approx. Pick larger dpi.

10″x8″ photo, zoom into area 4″x3″ to fill 720×540 frame:
720/4 = 180 dpi, 540/3 = 180 dpi.

Your mileage may vary, but for DV or DVD playback in North America, many people work in a 720×540 comp, then drop that into a 720×480 DV preset comp for rendering. I work in 720×480 and use pixel aspect ratio correction.

If you thought this was going to be fast and simple … welcome to After Effects! 🙂

Hope that helps,
Steve

[Keith Fredericks]

Yeah, it is amazing how many people from the print world (I work for a publisher) don’t understand what DPI means. They think it is an actual quality setting in an image rather than a scanning/printing setting. I remember when I was an intern at Disney, my superior told me to increase the DPI of an image in photoshop, to raise the quality.

From a quality standpoint, if you’re not going to transform your images in any way, make their resolution match exactly what the output resolution will be. Absent that, scan them in approximately, with a little extra, then crop them to the resolution you want. If you are going to transform them in anyway in AE, I go with high resolution images, which give you lots of flexibility. If you can manage it, it is always best to scale within AE in twos. It’s better to reduce an image by 50% than 49%, from a quality standpoint.

[Mustardgirl]

many thanks for these suggestions particularly the advice about scaling in twos….and may i say that the only hat i posess as an artist is the one i hold out for loose change!!!
cheers
🙂

mustardgirl