This task was devised in response to a learner's query about cropping images to an exact size. Cropping to an exact size isn't really practical - but this technique was about as close as you could get!
This particular task crops an image to 16 x 9 proportion - which better fits a widescreen monitor or TV - if that is where you want to show your images.
Also, If you want to provide your images ready sized for an online printing service, you might want to practice this technique. It will ensure you print exactly what you want to see.
Gimphoto doesn't have a cropping tool as such. You have to use the rectangular selection tool (arrowed left) to define your cropping area and then go to the menu option: IMAGE > CROP TO SELECTION.
This technique is not very precise but if you are merely concerned with finishing up with a sepicific part of an image, regardless of its dimensions or proportions, then you can use this technique.
Download the Venice Canalside image to practice.
So to get a specific size or proportion, using Canvas Size can provide the solution.
Unlike Photoshop or Paintshop Pro, Gimphoto doesn't have a particulary comprehensive Canvas Sizing tool, but it can still do the job.
In this task we will resize (and thereby crop) an image ot 16 x 9 proportions.
Download and open the Venice Canalside image. Then go to the menu option: IMAGE > CANVAS SIZE, which will show you the present canvas size. Pixels might be the best measuring increment to use. This image is 1600 pixels wide by 1200 pixels deep. It's an easy calculation to determine that it needs to be 900 pixels deep to fit 16 x 9 proportion. So we could 'crop' off the sky maybe.
First, 'unlock' the proportion lock of the image by clicking on the chain link - arrowed.
Then set the new Height of the image at A. 900 pixels
Because we want to crop off the top of the image, we have to 'Offset' the resize by settig the Y axis to -300 pixels (to shift it down).
You should see a guide line on the preview (C).
All that remains is to click on the 'Resize' button to complete the job.
The image should now look like the one below. If the crop is not quite right, you can Undo this action and then try again, this time varying the vertical offset by a few pixels.
TIP: If you want your image to be a specific print size, you should resize it the conventional way first, concentrating on the resolution you need, then resizing to the most important dimension (width or height).