[RAART]

Zeiss Makro Planar T* 2/50, mostly images where the environment dominates the people: https://www.flickr.com/photos/25114742@N07/sets/72157631412371474/

Zeiss Makro Planar T* 2/100, more images that get closer into the people and they can dominate the environment more: https://www.flickr.com/photos/25114742@N07/sets/72157625939982117/

Zeiss Planar T* 1.4/85, lots of detail and compression of distance but more balance in representing people in the context of the environment too: https://www.flickr.com/photos/25114742@N07/sets/72157625939982117/

So maybe it's just the beer talking, but for me the 85 sits somewhere in the middle and proves it's flexibility for certain subjects and the way I shoot...hic...

I think that you linked wrong the 85mm lens; maybe the beer influenced you a bit...

https://www.flickr.com/photos/25114742@N07/sets/72157630477301454/

[6BQ5]

Subjection isolation can be important. The 70-85mm focal length also gives you a magical depth of field which is perfect for sharp portraits and soft bokeh. Wide angle lenses will have too much depth of field in some cases. I think going beyond 100mm for portraits starts getting difficult. Your working distance is huge and getting the right perspective is much more difficult.

I'm not sure that 85mm is a special focal length by itself or if the mathematics for the optical design work out easier than say 80mm. Pentax went all number crazy with superstition and good luck in mind to produce a 77mm lens.

In the end, know and understand that you can take great portraits with any lens if you understand its strengths and weaknesses. I've had good (and bad) experiences photographing people with all sorts of focal lengths and lenses.

[Na Horuk]

Lots of good answers so far particularly about DoF, distortion and working distance/FoV. 85mm to 135mm were classical portrait focal lengths. The reason why 85mm is more popular is, I think, connected to APSC. On crop sensors, 135mm is really telephoto. If you look at some FoV equivalents, the portrait focal lengths become 55mm to 85mm. So 85mm fits both FF and APSC as a good portraiture lens.
The second reason is tradition. Some focal lengths are simply classic, and many different lenses were made in those focal lengths. 24, 28, 35, 50, 85, 135.. these are really common, each for its own reason, but after a while, the number itself becomes a reason. This is why Pentax stands out a little with its 31mm, 43mm, and 77mm. Of course, there have always been exceptions and lenses that are in between. Even some 50mm lenses are actually 52mm, but are still labelled as 50mm. A new trend these days is that there are many different camera formats, FF, APSC, APSH, m43, Q.. so those old conventions are less and less relevant.

[Tas]

I think that you linked wrong the 85mm lens; maybe the beer influenced you a bit...

https://www.flickr.com/photos/25114742@N07/sets/72157630477301454/

Sorry for that, but ta for the pick up.

[boriscleto]

The Pentax 85/1.4 is an expensive and rare lens because it was always an expensive and rare lens. Many pixies have to be caught and sacrificed at the correct phase of the moon to make the pixie dust that goes into * lenses.

[condor27596]

Knowing what I know about the 77 and the 50 that I've been using for portraits for two years I would say the 85 is way too telephoto.

I concede in advance it may be a lack of knowledge on my part.

[Na Horuk]

Knowing what I know about the 77 and the 50 that I've been using for portraits for two years I would say the 85 is way too telephoto. I concede in advance it may be a lack of knowledge on my part.

On a crop camera it is fairly long for portraiture. But on FF, where the focal length gained its fame, it is more comfortable.

[clackers]

The Pentax 85/1.4 is an expensive and rare lens because it was always an expensive and rare lens. Many pixies have to be caught and sacrificed at the correct phase of the moon to make the pixie dust that goes into * lenses.

Indeed, it's the job of the same contractors who club baby seals.

They go into valleys with pink LED lures and bottles of ether to drop their catches in.

[clackers]

The truth is that the 85mm is a much longer telephoto in terms of field of view on APSC - essentially it is like a 128mm lens which puts it into the longer end of the portrait spectrum.

Yes, this is the age of APS-C, which must have a lot to do with why the 135mm lens - standard in the film era - has lost popularity.

[boriscleto]

Yes, this is the age of APS-C, which must have a lot to do with why the 135mm lens - standard in the film era - has lost popularity.

135 is 202mm FoV on APS-C. Not really a portrait lens anymore, unless you are taking pictures from the other side of a large room. I'll be using mine on Sunday during a Raptor demonstration by the Cornell Lab of Ornithology. 135mm was on its way out as a part of the consumer kit by the early 80s. Only an enthusiast would walk away from the store with a 135 instead of a 70-210 or 70-150.

It didn't help that Pentax used the Takumar Bayonet optical formula for the A 135/2.8. Though I find that lens to be perfect for APS-C.

[formercanuck]

On a crop camera it is fairly long for portraiture. But on FF, where the focal length gained its fame, it is more comfortable.

True. 50mm (55mm) is close to 85mm on APS-C, which is probably why I use it a lot. 85mm (f/1.4 anyways) is GREAT for bokeh due to its long FL.

85mm f/1.4 Rokinon / Samyang is not all that expensive, and VERY fast for 85mm (and FF compatible!)

[stevebrot]

It is considered that 85mm in FF is the shortest FL where perspective distortions are not apparent.

The distortion in question is not a lens aberration, it is perspective distortion, and is simply a function of how close you are to the subject.

Exactly, it is simply perspective based on subject distance...no distortion involved. Your eyes show the same shorter focal length exaggeration at close distance as do longer lenses.

FWIW, even focal lengths as short as 50mm can be used for pleasing portraits on 35mm FF. It depends on the pose and how tight you frame the shot.


Steve

[GeneV]

I've gotten to like the FA77 so much for people at a comfortable distance with innocuous equipment, that I will be hoping for a fast 115mm for portraits on the FF. I'll probably have to settle for the zoom, though.

[Wild Mark]

The 85mm lenses I have include cemented elements (cost) with the faster ones (e.g. A*85/1.4 having ED glass etc) - these factors make manurfacture/ material costs high hence reflected in the lens pricing.

Also, 'demand' for such lenses might have been lower than other FL lenses meaning pricing had to be more for the lower production runs/ marketing required to sell them.

[brewmaster15]

Thanks everyone for sharing your thoughts,views, links,and experiences here.

I have a modest but growing collection of m42 Takumars here....I think I will keep an eye out for an m42 85mm super tak or smc tak. Sometimes you just have to try something out to really understand. That plus I have rarely met an old Tak I did not like Then I can play around with it compared to other focal lengths.
al