I don't know what this lens is. H Dallmeyer London BB n°10117.
It doesn't seem to be a genuine Dallmeyer lens. The barrel seems have been modified and cut for waterhouse slot. It should be a taking lens from the 19th century, and used as enlarging lens or projection lens. The mounting flange is included and I can't unscrew it. Otherwise it's a petzval optical design lens, with cemented front achromat and separated by air rear achromat.
Glasses are complete and in good condition. Brass barrel wears some marks and varnish loss. There is a waterhouse slot and a rack & pinion focusing system. A front inactinic screen (brown/red) is included.The image projected on a full plate ground glass is good and sharp. I guess this lens is able to take great pictures for large format photographers and wet plate enthusiasts. Check out my other antique lenses for sale.
L'item "Petzval Dallmeyer large format 240mm 5X7 6x8 brass lens" est en vente depuis le jeudi 21 mars 2019. Il est dans la catégorie "Photo, caméscopes\Photographie ancienne\Objectifs anciens". Le vendeur est "75photographica" et est localisé à/en Paris, Ile-de-France. Cet article peut être expédié aux pays suivants: Amérique, Europe, Asie, Australie.