A common image edit, needed for posting images to Artalyst, is the Crop and Resize of an image to create the 80x80 and 260x170 thumbnails. GIMP can make this extremely easy as you will see below. GIMP stands for GNU Image Manipulation Program. It is generally considered the best free alternative to Adobe Photoshop. The open source program is designed to be as powerful and complete, although arranged differently, as its pricey competitor. GIMP will run on multiple platforms including UNIX, Linux, Mac OS and Windows PC. You can download GIMP for free here: www.gimp.org

In this example, we will crop a section of our "Ship on Water" picture and resize it 260x170 to form our preview thumbnail for upload.

Step 1: Open your image in GIMP for editing

When you open GIMP, the first thing you will notice is that the tool windows are not docked into the main program window. This may take a little while to get used to for some. You can move the windows anywhere you like and they will remain. In the sample provided, the windows are placed over the main window.

Select from the GIMP main window menu, >File>Open>. Then you will be shown a window with the files located on your computer. Navigate to the correct folder and choose the file you want to edit, then click the Open button. The image is automatically zoomed to fit to the window. It is recommended to either move the tool windows away from the work area or to zoom out to show the complete image without obstruction as in the image provided.

Step 2: Crop the image

The power of GIMP makes this very simple. Once you have your image opened and on the screen where you can see where you need to work, select the crop tool. In the toolbox window, the crop tool is in the fourth column on the third row. The settings area in the lower half of the toolbox window will provide you with crop options. Be sure the fourth checkbox down, labeled "fixed" is checked and the drop-down to the right has "aspect ratio" selected. Then in the box directly below, enter the desired ratio to constrain the crop area. For a 260x170 pixel final image, enter 260:170 or mathematical derivative if you want to have less typing. Example, for the 80x80 thumbnail, you could use 80:80 or 1:1.

Now you can draw a crop box across your image by the click and drag method. You can click and drag in the center of the crop area to move it around, or click and drag the corner grips to resize. The crop area will always remain at the fixed ratio that you determined earlier. Once you have the cropped area adjusted like you wish, a single click in the center of the box will execute the crop.

Step 3: Resize the image

Now that your image is cropped just like you want, you need to resize it to exactly 260x170. Because you forced the crop tool to a ration of 260:170, this process will be simple. Select from the GIMP main window menu, >Image>Scale Image>. A dialog box will open to enter the values.

In the Scale Image dialog box, enter the correct pixel size in the top two fields. Be sure that the chain links to the right of the fields are connected and the drop down menu right of that is set to pixels. Enter 260 for width, click in the height field and you will see that 170 automatically comes up. Click the Scale button on the bottom and the image will be resized.

Step 4: Save the image

Save your image to your computer by selecting >File>Save As> from the drop-down menu on the main GIMP window menu. I recommend saving the image using a filename that is unique, but identifies the image as a preview thumbnail. In this case, the "-pv" is added to the end of the file name. At the bottom just above the Help button, the file type can be indicated. By default this is set to (By Extension) So if your filename has .jpg at the end, the file will save as a jpg.

When you click the Save button, a new dialog box opens to adjust the jpg quality. Usually 70 is adequate for reducing the size enough to upload to Artalyst. Images are different so play around with the settings. Click on Save and you have a preview thumbnail ready to upload to Artalyst.

There are other free, web-based, paint or image editing programs on the internet. You can always try one of the others to see if you like them better. It is recommended to use an image editing program that you install on your computer, like GIMP, for many reasons. They are faster, create a more precise edit, crop, resize, etc., create a cleaner image with less artifacts and distortion.