This article uses SharpResize
and is updated for version 2, which creates better thumbnails. Version 2 is available shortly as beta.
In this article:
- Opening an Image
- Quality and Size
- Additional Output Sizes
- Batch Image Processing
Opening an Image
There are several ways to get your image into SharpResize.
- New from clipboard using File > New From Clipboard or cmd-N
- Drag the image onto application's dock icon
- Drag the image onto application icon or alias
- Drag the image into SharpResize's image well
- File > Open or cmd-O
You can grab an area of the screen using cmd-ctrl-shift-4. Drag a rectangle and see the width and height of your selection. It's not an easy shortcut to remember but worthwhile.
In addition there are toolbar buttons for New from Clipboard, Open and Save.
A note about retina screens. This is a confusing subject, pixels can refer to the number of dots within an image and the actual physical pixels on the display, or it can be used as a a measurement similar to points.
Because SharpResize is designed primarily for resizing images for the web, it will display your image at '1x' - ie the size that it would appear if you specified your size in pixels in a CSS. If you're using a retina screen, then this would obviously look fuzzy and you wouldn't be able to make proper judgement when making adjustments to sharpness etc.
So SharpResize has a setting in Preferences:
As it says, the 2x version of your image will be displayed while you're working. This setting should be auto-detected when you first run SharpResize.
If you want to save the actual version of the image that you're seeing while you're working, make sure that you have 2x selected in the Additional sizes.
Quality and size
When you open a new image, the width and height won't immediately set themselves to the size of your image because Sharpresize is about creating thumbnails, and the width and height fields may be set to the size that you want your thumbnail to end up.
If you do want to set the output size to the actual size of the image, press 'Actual' or cmd-=
If you want the resized image to have the same aspect ratio as the original, make sure the padlock is in the 'locked' position.
If the padlock is in the 'unlock' position, then you can set the height and width to whatever you like, and you'll see additional controls relating to whether you want to crop your original image to size or add white, grey or black etc.
Resizing will be performed with Lanczos sharpening which is noticeably better than the more usual bicubic. You will see the output image displayed in the image well.
The Sharpening slider applies a further filter to further improve a resized image. Use judiciously - too much will result in an artificial look. The best setting here will depend on the image. Most pictures seem to look best with the slider about a third of the way. If the image includes text, any more than a small amount of sharpening can spoil the anti-aliasing and make the text look jagged.
Under the Output File tab, the Quality slider sets the jpeg compression of the output. (If you have the jpg output file format selected.) For maximum quality you'll also get the maximum file size but the file size can be reduced significantly (maybe halved) by backing off that slider a tiny bit below maximum.
Version 2 has more controls for adjusting the output image, and also a few filters, such as Sepia and Black and White.
Like a little extra vibrance with your sharpening? No problem.
Additional Output Sizes
The height and width fields are important, they'll set the dimensions of the primary output image for all input images. You can now create and select additional sizes (for example, a banner-format image, or a square image, or a @2x image). These can be relative to the original image size, or your primary output image, or have absolute dimensions.
Batch Image Processing
Version 2 allows you to drag and drop or open multiple images. They'll all be resized using the height and width that you've set and all using the same sharpness and adjustments that you've set. if you've created and selected additional output sizes, each input image will be saved with all output sizes.
You can save the image using File > Save, cmd-S or the toolbar Save button.
If you have opened multiple images
, you will be asked to choose a folder for the output images (at least one output image for each that you've opened). Files will be saved with their original names. If you've chosen additional sizes for each image, the filename modifier will be applied.
There's a preference to set whether SR saves all of these images directly in the folder that you've chosen, or whether it creates a new folder with a unique name and saves the images within that. The latter method is set by default, and is less likely to cause filename conflicts.
If you have opened a single image (regardless of how many output images you want) then you'll be asked to choose a filename, and your output images will be saved with that filename, with modifier where appropriate.