Steinheil Group Antiplanet 21 mm in Aluminum Mount (!), c. 1880

1) Steinheil in Munich. A very rare Steinheil lens in an aluminum mount. Lens no. 36862, aperture range: 1/2–8, lens height with lens hood only 35 mm, with a 50 mm diameter screw-on ring, lenses quite clean. – Note: In order to make lenses lighter, the much lighter material aluminum was used instead of brass in the 1880s. This was only for a very short time, however, as aluminum was three times more expensive to produce than brass at the time. Sales of such lenses were so low that brass was used again. – In addition: Unmarked brass landscape lens, c. 1870–80, for plug-in apertures. Lens height 65 mm, glass fairly clean. – And: 2) lens elements, presumably by Steinheil: a) Cemented double lens, marked in lead: 1 1/2 m, diameter 26 mm, height 19 mm; b) Cemented double lens, marked in lead: 1:4 f=180 mm, diameter 45 mm, height 8 mm.

布雷克拍品等级是为了方便竞买人判断拍卖品的成色而设置的。布雷克等级用1到6级来标注外观和功能的成色，(从非常好到非常差)。 在目录图册里用括号里的2个数字来表示，前一个数字表示外观成色的级别，后一个数字表示功能成色的级别。如(3/2)表示外观成色是3(满意的)，功能成色2(好)。 成色 定义参照下列标准： 1 - 非常好 (未使用过，没有使用痕迹) 2 - 好 (新，极少的使用痕迹) 3 - 满意的 (普通的使用痕迹) 4 - 及格的 (明显的使用痕迹，某个非主要部件是后配的) 5 - 有缺陷的 (极明显的使用痕迹, 某个主要部件是后配的，功能上有缺陷，需要修理) 6 - 非常差 (严重破损, 缺少重要部件)