[WEB4LIB] esolution for scanning images for the web

[Bob Rasmussen]

On Tue, 17 Aug 1999, Yvonne Reynolds wrote:

> 
> Hi!
> May I ask a very basic question?  Does everyone scan images to be 
> used on the web (slides and photographs) at 72dpi/ppi?  Or do you 
> scan at a higher resolution and then resample?  Pros and cons of 
> either?   Which is the preferred format for storing the images - tiff 
> or bmp before converting to jpeg?

I know some general cross references have been given, but let me point out
just a couple things:

1. 72 dpi is a theoretical pixel density for a screen. It's related to your
scanning decision, but indirectly. Decide how many pixels wide (or high) you
want the picture on the screen. Then measure your picture and do the math.

2. I prefer to scan at the intended display density. Resampling (resizing)
never gives you MORE information than you started with, and often gives you
LESS.

3. If your scanning software can't output jpeg, then tiff vs. bmp shouldn't
matter much. Note, though, that there are many "flavors" of TIFF, and you
could have problems with an unsupported flavor. I've never had that problem
with BMP.

-- 
Regards,
....Bob Rasmussen,   President,   Rasmussen Software, Inc.

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