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Drew Bedo
14-Apr-2012, 16:44
I have been looking at old brass lenses lately . . .the ones that used to go for <$20 at the camera shows in the ‘80s and’90s. Now I am interested and have a few questions.

What is the difference between a “landscape” lens and a “portrate”l ens?

Can a Petzval lens be either or both?

Is there a difference between a camera lens and a magic lantern lens in this era of photography (1860-1890)?

Who made the "good" ones?

Old-N-Feeble
14-Apr-2012, 20:21
I think "Mark Sawyer" is one of many to ask.

sinhof
15-Apr-2012, 04:47
I use my Hermagis Portrait with portraits. It makes "Hollywood-soft" and has mild contrast. Bokeh in the corners is huge. For landscaping I use my Rodenstock Bistigmats. They are good enough from corner to corner. One year ago I made a test with (Sinar P plus) Symmar-S MC 240mm and Bistigmat 240mm. I used Canon 5D Mk2 and Photoshop CS5 only with normal things for the colours. More than half did not see, what is Bistigmat“s picture.
Old Tessar is different, normal Bistigmats and Weitwinkel-Bistigmats are different too. Maybe individual quality ?
summa summarum : portrait lences are soft, landscape lences not so much.

Mark Sawyer
15-Apr-2012, 11:08
I answered in this thread, but will cross-post over here,

http://www.largeformatphotography.info/forum/showthread.php?89675-Vintage-Brass-Lenses

Strictly speaking, a "Landscape Lens" is a simple meniscus lens. William Wollaston's camear obscura Landscape Lens of about 1812 was the first, predating photography, and was used on the very earliest photographic cameras. Later Landscape lenses were cemented double-element achromats (you need add a negative lens to make an achromat), like Scovill's Waterbury Lens or Dalot Single View. Landscape lenses need to be used at fairly small apertures, f/16 or less, to make a conventionally sharp image. Wider apertures give a soft focus effect. The Kodak Portrait Lens and Imagon are teachnically "Landscape Lenses", even though they were made specifically for portraiture.

"Portrait Lens" is a term tham evolved along with the technical needs and aesthetics of photography. At first it meant a fast lens (about f/5 or faster) so the subjects didn't have to sit still too long. Later, it became synonymous with being a softy lens that minimized skin flaws and added a glow. Today it just means a semi-fast lens (for shallow depth of field, not speed), and an appropriate focal length.

The front element of a Petzval is a cemented doublet and can be used by itself as a landscape lens.

People argue whether there's a difference in quality between Magic Lantern lenses and camera lenses. In using good quality lenses, I haven't seen any, but there were also some very cheap Magic Lantern lenses that were pretty poor quality. Camera lenses had methods of aperture control, (Waterhouse stops, rotary stops, irises...) except for the very earliest lenses.

Drew Bedo
15-Apr-2012, 20:36
Mark: Thanks. Thats the type of explanation I was looking for.

Mark Sawyer
16-Apr-2012, 12:06
One with lots of typos? :)