Digital Light & Color

Hi,
The Operation Total image size in the transformation Resize expects the target file size in megapixels. But it seems to be valid only for 8 bit images. For 16 bit and 24 bit images one half or one third the target size has to be entered, otherwise you will end up with a file twice or three times the intended size.

Also, it is no longer possible to rescale (not resample) the image by changing its height and width, only by changing its resolution. Perhaps this was necessary to accommodate the transaction into workflows, or have I overlooked it somewhere?

PWP latest version.

David

David,

I tried the Total Size resizing, and couldn't find fault with it. Could it be that that the size is specified in Megapixels, which is ~ numerically the same as uncompressed file size in Megabytes for 8 bit B&W images. For 24bit colour you would have to multiply megapixels by ~3, for 48bit colour by ~6.

If what you need is to change the nominal physical dimensions of the image, leaving the pixels alone, you need to change the conversion factor: i.e. the DPI: Operation=reset resolution only, then adjust DPI and watch the New Width and Height displays. Out of the 3 properties: physical dimensions, pixel dimensions, and DPI only 2 are independent - the third one is determined by the chosen values of the other two.

Maciej,

It is more or less the question of how you understand the Total image size. My understanding was that if I enter 1.0 into the field Megapixels, the resize window will update the New File size of the image to 1MB whatever bit the image is. I see no problem, for me it only means to take into consideration also the bits of the source image and divide accordingly the value of the Total image size Megapixels.
For example, to resize a 24bit image to New file size of 1 MB, the value of 0.333 has to be entered to the Megapixels field, for 48 bit it has to be about 0.166, etc.


Now, to my next question. I think I understand what is behind scaling and resampling. What I was looking for, was the possibility to only change print size: width or height in inches (not image size in pixels), and let the DPI be adjusted automatically, as it was possible in PWP 4.0 with the preserve option. With "Operation=reset resolution only" you cannot change the width and height directly, only through DPI.

Thanks for sharing.
David

David

Why not using the resize function of Crop/Add Border ?
You can enter a size in inches ,mm ,cm or pixels and the DPI value and it resizes to that size.
Normally when resizing to a spezified print size a definate aspect ratio is also desired, and Crop/Add border makes it all in one task.