hi @nbcommunication,
 
	thanks for your quick response.
 
 
	yes, that's what i thought, and i was hoping that there would be an easy way to reduce the image size with processwire.
 
	i'm doing it now like this. I reduce the imagesize and do some croping to squared images via php, then save it to the temp-folder and link to this image.
 
            $instagram = $modules->get('InstagramBasicDisplayApi');
            // Get 10 images
            $images = $instagram->getImages(10);
            $counter = '';
            echo '<div class="start_instagram uk-grid-column-small uk-grid-row-small uk-child-width-1-2@s uk-child-width-1-5@m" uk-grid>';
            foreach ($images as $image) {
                $counter = $counter + 1;
                $instagramImageUrl = $image->src;
                $imageData = file_get_contents($instagramImageUrl);
                $fileName = 'instaBild' . $counter . '.jpg';
                $filePath = $config->paths->assets . "instaTemp/" . $fileName;
                // Verkleinere das Bild auf eine maximale Breite von 300px
                $maxWidth = 300;
                list($width, $height) = getimagesizefromstring($imageData);
                $aspectRatio = $width / $height;
                $newWidth = min($maxWidth, $width);
                $newHeight = $newWidth / $aspectRatio;
                // Erstelle ein leeres quadratisches Bild
                $imageResized = imagecreatetruecolor($maxWidth, $maxWidth);
                $imageSource = imagecreatefromstring($imageData);
                // Berechne die Position für das Cropping (zentriert)
                $cropX = 0;
                $cropY = 0;
                if ($width > $height) {
                    // Querformat, seitlich beschnitten
                    $cropX = ($width - $height) / 2;
                } elseif ($width < $height) {
                    // Hochformat, oben und unten beschnitten
                    $cropY = ($height - $width) / 2;
                }
                // Führe das Cropping durch
                imagecopyresampled($imageResized, $imageSource, 0, 0, $cropX, $cropY, $maxWidth, $maxWidth, $width - (2 * $cropX), $height - (2 * $cropY));
                // Speichere das verkleinerte und beschnittene Bild
                imagejpeg($imageResized, $filePath);
                imagedestroy($imageResized);
                imagedestroy($imageSource);
                // echo $fileName . " auf " . $filePath . " gespeichert.<br>";
                $tempPath = "/site/assets/instaTemp/" . $fileName;
                $altDesc = $image->alt;
                echo "<div>
                <a href='". $image->href ."' target='insta'>
                <img src='" . $tempPath . "' alt='" . $altDesc . "' title='". $altDesc ."'>
                </a>
                </div>";
            }
            echo '</div>';
            ?>
	i think this solution is OK, since i have proCache running and so it doesn't regenerate on every page load, or am i wrong? 
	there are 10 images loaded which are now about 160kb in size as compared to the 3mb for the originals.
 
	suggestions for improvements are still welcome, i wanted to make sure i hadn't overlooked any major option.