biology coarse adjustment kn diaphragm education eyepiece fine adjustment knob instrument lens medical microscope object holder objective turret ocular lens optic optical research science viewing backdrop background box cardboard concept copyspace corrugated corrugations Dirt graphic grunge grungy lines old packing packing box paper parchment pink realistic scrapbooking smudge texture wrinkles blue sepia abstract banner christmas cold design festive greeting illustration merry merry christmas New original red season stars unique vector wishes words xmas beautiful color colourful decorative diamonds frame gems glass gold jewels luxury metallic orange ruby shiny sparkling spots square stones white purple colour green image nature plant print silhouette tree wallpaper architecture atmospheric berlin bike bikes building buildings bushes footpath forest pine home house houses idyllic lane peaceful pines quiet rural scenery street lantern trees animals antenna antennae brilliant bug closeup common blow-fly common fly fly Green bottle fly insect krayker Lucilia sericata macro necrotic pest wings