Couple questions for a new project

[frenchym3]

Hi there,
As we all know we can't enhance the resolution of a already scanned picture, but I'm sure there's always some ways around...
From a regular picture size I'm making a poster size, there will be 8 or 10 8.5x10 sheets that will make one big.
When I blow it to that size I have those "shark teeth" looking edges around the silhoutte. How do Iget rid of them?
The other thing is probably very simple for all of you; how do I devide a picture into 8 or 10 even rectangle? like I said before, each rectangle will be blown up and printed on a 8.5x10 sheet, at the end they will make a big poster.
Thanks everyone.

 

[TrojanWarBlade]

The best you can do is soften such edges by blurring them or smudging them. The ideal solution is to re-san at a much higher resolution.
I do not really know photoshop at all but I believe it has a facility to split an image up for use in tables for a webpage so you may be able to use that to chop up your image.


Trojan.

 

[jimoblak]

If you are looking at shark teeth, then you may have too low of resolution to enlarge so much. Ideally, these jaggies should be no larger than gerbil teeth.

- - I hope this helps - -
_{(Complain to someone else if it doesn't)}

 

[MercedesBainz]

To divide your picture into even rectangles use either grids or guides. Go to View -> Show -> Guides/Grid. And make sure to select Snap to grid/Guides to enable accurate selection.

 

[nzingaimani]

Actually, you can pump up the resolution, you simply cannot increase the detail. The trick is to increase resolution (Image>Size>DPI=300 or more) then duplicate the layer (copy1). Move the layer one pixel right and one pixel left (diagonally) to fill the resolution 'gap' between pixels. Actually, it works best to move it however many pixels required to fill the center of the gap between the 'jaggies'. Set your transparency to 50% and you should see an improvement in the photo. Duplicate copy1 again (copy2), then position it to split the now smaller jaggies immediately to the right (when you reposition the copy1 layer you create two gaps, copy2 will fit in the second) leaving the second 'new' gap open for the next duplicate layer (copy3). Repeat process to generate image filler for 'jaggies' until you are pleased with the look of the image. As you fill gaps, check the look of the image and determine when you are satisfied. The 50% trnsp may need to be reduced depending on the number of layers used as the density of the image builds up with each layer. Once it looks pleasing to you, flatten the image, gaussian blur for 1-5 pixels depending on the size of the image and use image curves to lighten dense areas to match the original image. Change some of the layer blending modes to improve the appearance to taste. Save. Done