可以鱼眼太贵, 又不实用.

[此贴子已经被作者于2004-8-23 10:39:16编辑过]

又加一张感觉不错的:

以下是引用papayadress在2004-8-24 0:38:34的发言：

以下是引用redbean在2004-8-23 22:25:52的发言：
什么是鱼眼照片？不会真是摄的鱼眼吧？不要笑我哦

焦距小于35mm， 都能称作鱼眼镜头了， 焦距越小景深越大，射入的景物面积也大。

焦距<35mm就可以称鱼眼了?

[face=Courier New]Robert W. Wood originally coined the term “fish-eye” in his book Physical Optics1 in the context of a discussion about the
refraction of light and the refraction of rays entering the level surface of a pond. Wood goes on to describe a water filled
pinhole camera (his “fish-eye” camera) that is capable of simulating the “fish-eye” view of the world. His homemade
camera was functional and produced interesting examples of images that “embrace” 180 degree fields of view.

In “Photographic Lenses”2 published in 1932, Willy Merté credits the first real “fish-eye” lens to R. Hill3. According to
Kingslake4, the Hill Sky Lens of 1924 was manufactured by Beck of London. Hill evidently is the first to develop a glass
“fish-eye” lens, and his design was found to be useful to meteorologists for all-sky photography.

Fisheye lenses for 35 mm photography are typically found in two classes:

a. Full frame fisheye lenses capture a hemispherical image across the diagonal of the 35 mm frame. These
lenses range in focal length from 14-16 mm and have a ratio of back focal distance to effective focal
length of 2.2 to 2.4.

b. Circular image (hemispherical) fisheye lenses capture a full 180 degrees within the narrow height of the
35 mm film frame. The lenses in this class have effective focal lengths ranging from 6 to 8 mm and have
a ratio of back focal distance to effective focal length of 4.55- 4.75.[/face]

[此贴子已经被作者于2004-8-25 0:57:07编辑过]

以下是引用skyblade在2004-8-27 16:51:20的发言：
LOL
此35mm非彼35mm

?