Thanks. I'll keep your recipe. I've not had to do this sort of thing
ever but maybe the day will arrive. I'm also not much up to
experimentation today as I have an eye patch over one eye.
Chuck Norcutt
Ken Norton wrote:
>> Mr. Sachs was so adamant on this point that I don't think he'd agree
>> with your exceptions. But you have the power to prove him wrong. Can
>> you demonstrate your point using Picture Window Pro... his own product?
>>
>
> Absolutely!
>
> If I need to upsize an image (which is a normal requirement with 5MP E-1 and
> A1 files), and the image contains straight lines in it, you absolutely will
> get the saw-tooth pattern high-contrast edges within the image.
>
> To break those edges up, you need to use multiple steps. But if you do the
> 10% resizing, things just look mushy and nasty. The resulting image will
> lack the definition a single-step resizing has. So, to reduce the pattern,
> here is my recommendation.
>
> 1. Resize by some odd percentage like 113%.
> 2. Resize by another odd percentage like 134%
> 3. Resize by another oddball like 121%
>
> I used Fibonacci numbers in this example which yielded an almost doubling in
> size in three steps. By doing this, the saw-tooth artifacts are nearly
> eliminated or at least reduced enough to be a non-issue most of the time.
>
> I've also experimented with image rotation (full image--no cropping) during
> the steps. For example:
> 1. Rotate image 13 degrees CCW (anti-clockwise)
> 2. Resize by 113%
> 3. Rotate image 34 degrees CCW
> 4. Resize by 134%
> 5. Rotate image 21 degrees CCW
> 6. Resize by 121%
> 7. Rotate image 68 degrees CW
> 8. Trim off the white edge to your original image area.
>
> This has given simply outstanding results. Horribly time-consuming in
> Photoshop, but much faster in PWP 5.0.
>
> Resizing is pretty much a lost art now because of higher pixel-count
> sensors. Only us dinosaurs with E-1s have to go through these things.
>
> AG
--
_________________________________________________________________
Options: http://lists.thomasclausen.net/mailman/listinfo/olympus
Archives: http://lists.thomasclausen.net/mailman/private/olympus/
Themed Olympus Photo Exhibition: http://www.tope.nl/
|