To get started selling digital image downloads using Pixaria Gallery, browse to the product administration tools under the 'Products' tab of the admin area navigation and choose the link to create a new product.

Create a new product
Within the create product form, you will need to select 'Instant image download' from the product types options, enter a title for the new product and an optional description in the space provided. This information will be displayed to users purchasing the products via the software front end.
Click on the 'Options' tab to display the tools for configuring the image download settings. To begin adding options, click on the 'Add product option group' button which will display a dialog where you can enter details of the image download dimensions and a name for the option.
In this example, we will select the option to download the original image, give this option a name of 'Original high-resolution image' and instruct the software to add 50 currency units to the base price. Click on the 'Save option' button to add the option to this product.

Option for an original size image download
Next we will add another option, this time for a 1000 pixel image download. Click again on the 'Add product option group' button and this time enter a custom pixel size of 1000 pixels in the space provided. Choose to increase the price by 20 currency units and give the option a name of '1000 Pixel image'.

Option for a 1000 pixel size image download
It's possible to add as many download size options as needed and the options can be rearranged in order by drag and drop.

Rearrange options by drag and drop
When you're happy with the options, save the new product to make it visible on the front end of the site.
Once an image download product is configured and active, users can configure the product from the purchase options available for an image in the software front end. Note that users will only see image sizing options that are applicable for the image being viewed.
No, web resolution means the comp image. DPI is not a relevant concept for digital downloads because it relates to output pixel density not to actual pixel dimensions. For example, a 1000 x 1000 pixel image printed at 72dpi will be 13 inches square while if the same image is printed at 300dpi, it will be 3.3 inches square.
The more pixels an image has, the larger it will be when printed at a high pixel density (resolution). This is why images with large numbers of pixels are called high-resolution.
No, it's the pixel size that's changes (see question above).
Pixaria already does this. The custom sizes will always fit the image inside the dimensions specified. If you choose a custom size of 2000 x 2000 pixels a panoramic image will be scaled so that its longest edge as 2000 pixels but it retains it's aspect ratio.
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