Well, I'm pretty sure you're not actually using a PDF file as a background image, because Access doesn't support that, so I assume you're converting the PDF image to a JPEG and using that as the form background.
There's no way, technically, to make an image smaller without losing resolution. Pixels are always the same size, so if you shrink an image, it has to have fewer pixels in it. If 2 pixels get shrunk to 1, you've lost the information in one of those pixels.
However, there are graphics transformations that can minimize the loss, perhaps even making it invisible. For example, you can compute the average of 2 pixels and replace both of them with the average, which helps make jagged edges look smoother. This is called "antialiasing", and most graphics programs can do it. So one possibility is that you can resize the image with a graphics program before you load it into Access.
If you don't have a graphics program that can do that, you may still be able to improve your image quality. Distortion can be minimized by ensuring that the sizes are related by simple ratios, such as 1:2, 1:3, or 2:3. If you can control the resolution of the JPEG and/or the size of the form, you may be able to achieve an acceptable image. To avoid confusion, the form's Picture Size Mode property should be set to "Clip". Otherwise, Access may try to resize the image after you've already done so, and you might not be able to tell whether your efforts are succeeding.
Rick Sprague
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