These cropped thumbnails do not show the full extent of the original images
One of the most popular uses of the Wingleader Archive is as a modeller's instant reference guide. The 40,000+ photos contain all sorts of detail photos of military aircraft from 1910 through to 1970, including this close up of the machine gun pack fitted to a Bristol Blenheim IV at Bircham Newton in 1940. The aircraft presumably has been painted with Sky undersides and the dark staining around the two guns on the right of the photo is where the previous black/white scheme has worn through. If you have Photoshop then you can download the 1500pw large version of this image and pull the shadows out to reveal more detail.