cropping,resizing, resampling, bicubic etc.

[Robyn]

I'm just a tad confused about all this. I know how to resize and crop etc. etc. What I'm confused about is when to use resampling? What is the difference between bicubic smoother (and then I read somewhere to use the unsharp mask after this) and bicubic sharpener.........and those other options listed after you tick the resample image box.

When do you need to use these options......if at all??

[Daviskw]

Hi there Robyn

You only use resampling when you need to change the amount of pixels in your drawing. Say you have a 4 by 6 drawing you want to increase to 5 by 7 and maintain the present 250 dpi your drawing now processes. This would be called upsampling and would require the resampling to be checked. Elements would then have to insert pixels in your drawing by comparing adjacent pixels and interpolating the new pixel. This process can use more than one method and they are listed in the drop down box next to the resample check box. The three most often used are Bicubic, Bicubic Sharper, Bicubic smoother.
As you have stated Bicubic smoother is recommended when upsampling and Bicubic sharper when down sampling. Bicubic should be used if you get halos when using the other two methods, if is safer but not as strong. The process of inventing pixels or removing pixels often makes the photo soft or slightly out of focus. That is why Unshark mask is often required after resampling.
If you have plenty of pixels in your drawing you should avoid resampling when possible. It is best to keep resampling unchecked, change one of your drawing side dimensions, the other will be changed automatically, and see if you still have enough resolution (dpi). You should use resampling as a last resort.

Butch

[Robyn]

Butch,

Thank you very much for taking the time with such a comprehensive reply. That's exactly what I wanted to know. I shall print it out and keep it in my folder of "goodies".:D

[Ward Grant]

I second Robyn's thanks.