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11-04-2010, 12:13 PM   #1
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85mm vs 100mm M

I've got to do some lens consolidation. As the winter months draw in, so I thought I'd see the benefits of the f2 aperture on my 85mm for indoor portraits. In reality, even with fast film (I've gone retro), I am getting down to silly slow apertures where my new baby boy just goes into a blur. I've come to the conclusion a flash or two will have to be purchased. Plus, I really need f5.6-f11 when close up in order to get satisfactory depth of field.

I've got an issue now with which lens to keep and which to get rid of. My 85mm's advantage over the 100mm is that its a little shorter, a bit closer to normal, so that you don't notice the tele effect, but also that its got that lovely great front element, like a doey eyed dog. Aside from that, its twice the price of my 100mm, which buys a lot of nappies and beer.

Which would people keep of the two?

(I've got the same problem now with the 2.8/40 and 2.8/35, but am decided on that already...the minimum focus distance of the 35 wins out over the 40)

11-04-2010, 12:45 PM   #2
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I would keep the 85mm. They are harder to find, so if you changed your mind after you sold it would take longer to replace it.
11-04-2010, 12:56 PM   #3
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I never had the 100 but M85 is sweet lens. I only sold it for the 77ltd. It's faster than 100 and has nice feel to images. Although I have to say I used mine wide open nearly all the time...
11-04-2010, 01:00 PM   #4
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I'd sell them both and get a 90mm macro.

11-05-2010, 05:40 AM   #5
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Those are both lenses hard to come by. Flash guns on the other hand are rather pedestrian and you will soon regret having traded an M lens for it, especially one of the short-tele M primes. Gosh, it took me half a year until I finally found an M 100mm on ebay.

You just don't trade away M primes. Period.
11-05-2010, 08:48 AM   #6
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I've got both an M85 and M100, and decided I want to let go of the 100. It's a lot sharper, but since I use these lenses mostly for portraits, the 85 is sharp enough, and I like the feel on that one better. There's just something special about the pictures I'm getting with the 85. I also have an M135 when I want to go longer, so I think I won't miss the M100 too much, but somehow there don't appear to be any takers for the lens locally...
11-05-2010, 09:35 AM   #7
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My kit's close: In that vicinity I have a Jupiter-9 (350g) and a Nikkor 85/2 (300g) (slightly modded for Pentax); and a Vivitar-Komine 90/2.8 macro (470g); and a Meyer Trioplan 100/2.8 (260g). All manual. Of those, the Nikkor 85/2 is always in my bag; I *could* get by without the Jupiter and the Meyer (reluctantly). I'd consider augmenting the Vivitar+Meyer with a 100/2.8 WR macro. But the 85 gets used.

80-85mm has been a great FL for portraits in all the formats I've used (6x9, 6x6, 645, 135/FF, 135/HF-APSC). I consider a fast 85 as vital a tool as fast 24-50-135's. And not just portraits -- the 85/2 is a lens of choice for ill-lit spaces. Not too long, not too short, not too slow, just right.
11-05-2010, 09:41 AM   #8
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Camera Gear Rule #1: You can never have too many lenses

11-05-2010, 09:56 AM   #9
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M85/2, just beautiful. This one was using M85/2

11-05-2010, 01:43 PM   #10
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QuoteOriginally posted by yusuf Quote
M85/2, just beautiful. This one was using M85/2
That is just lovely. I am a huge fan of the FA77, and I really need a macro in the 100mm range before any other lens around that length, but I keep seeing M85 shots that draw me in.
11-05-2010, 10:30 PM   #11
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QuoteOriginally posted by GeneV Quote
That is just lovely. I am a huge fan of the FA77, and I really need a macro in the 100mm range before any other lens around that length, but I keep seeing M85 shots that draw me in.
Yeah me too, FA77 is awesome but this little lens is a gem too - I never let it go even after getting 77mm, in fact keep shooting with it whenever I need to get some change from FA77mm. I do not have experience with k85/1.8, but used to have 85/1.9 earlier and I preferred M85/2 over it - 1.9/2 is not a big difference and m85/2 seems to be a bit sharper.
11-06-2010, 02:27 PM   #12
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Funny, I have recently aquired an M85 and have probably already used it more than the M100 2.8 Ive had for several months. They are the only two old manual lenses Ive paid significant money for and as theyre very close in focal length, I might get rid of one, so Im in the same position, but with less urgency. Ive honestly not done any testing between the two, and as I say, Ive hardly used the 100, but Im fairly sure it would go before the 85. The 85 is soft wide open, but its useable. The 100 has significant purple fringing wide open. Both are too long on APS-C to really use as walkabouts, but I think in the near future Ill try some kind of comparison.

It wouldnt be fair to dump the 100 without giving it due attention first. I recently saw an A version for only 10GBP more than I paid for my M, in the same shop, so was a bit peeved.
11-06-2010, 06:48 PM   #13
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QuoteOriginally posted by Jonathan Mac Quote
The 85 is soft wide open, but its useable.
not really into starting an argument but rather an informative exchange of thoughts, but I would vehemently disagree with the notion that it is soft wide open. it is actually very sharp if you nail the focus perfectly. so it's either focusing error or a lens issue if this lens was indeed soft wide open. if there was any real issue with the lens, it would be the glowing (blue fringing) at wider apertures, other than that, the lens is marvelous.

Last edited by Pentaxor; 11-06-2010 at 11:39 PM.
11-06-2010, 11:04 PM   #14
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Soft Wide Open

Often I hear lens "x" or lens "y" is soft wide open. What is the case, however, is DOF is shallower wide open, of course, and this is often mis-interpreted as softness.

As Pentaxor says, nailing the focus is most critical wide open. Evaluating the shot for sharpness must take into account the existing DOF--this is where evaluations for sharpness wide-open go astray; they fail to realize the DOF at hand in a wide open shot.
11-07-2010, 01:22 AM   #15
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QuoteOriginally posted by Pentaxor Quote
not really into starting an argument but rather an informative exchange of thoughts, but I would vehemently disagree with the notion that it is soft wide open. it is actually very sharp if you nail the focus perfectly. so it's either focusing error or a lens issue if this lens was indeed soft wide open. if there was any real issue with the lens, it would be the glowing (blue fringing) at wider apertures, other than that, the lens is marvelous.
I take your point, and maybe I came across as brusque in that statement. I think that everyone has a different point at which normal progressive softness when opening the aperture actually becomes "soft". The 85/2 is certainly no softer wide open than most lenses, but I see a fairly big sharpness difference between f2 & f2.8. It is certainly usable wide open, maybe even very useable, but these are all subjective measures. The blue fringing does also have the effect of reducing sharpness, by blurring lines that out to be clean. For me, as the longer focal length usually gives ample subject separation even at f2.8, that is where I usually use it. I do agree that its a marvellous lens: colour, contrast, "3D pop" are all there, wide open or not.
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