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Meyer-Optik Orestor / Pentacon 100mm f/2.8 (M42)

Reviews Views Date of last review
8 61,772 Fri March 6, 2020
Recommended By Average Price Average User Rating
100% of reviewers $107.50 9.13
Meyer-Optik Orestor / Pentacon 100mm f/2.8 (M42)

Meyer-Optik Orestor / Pentacon 100mm f/2.8 (M42)
Meyer-Optik Orestor / Pentacon 100mm f/2.8 (M42)
Meyer-Optik Orestor / Pentacon 100mm f/2.8 (M42)

Classic lens from former DDR. The lens in pic 1 is an early "thin" version one-ring preset (pull the ring out to reset the f-stop), this has a 15 blade iris. Later "fat" versions are M42, 6 blade iris, with the aperture ring at the mount end, these are probably the most common (pic 3). The pentacon version in pic 2 is a standard M42 with a stop-down preview button.
Lens aperture control -M42 lenses.
Can also be found in exacta bayonet mount.

Optics: 5 elements / 4 groups
Filter thread: 49mm
Aperture: f2.8 - f22, half stop clicks.
Iris: 6 blade
CFD: 1.1m/3.5'
Focus throw: ~ 320
Weight: ~ 285g (pentacon)
Mount Type: M42 Screwmount
Price History:

Add Review of Meyer-Optik Orestor / Pentacon 100mm f/2.8 (M42)
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New Member

Registered: March, 2020
Posts: 1
Lens Review Date: March 6, 2020 I can recommend this lens: Yes | Price: $30.00 | Rating: 10 

Pros: Sharp, Bokah.
Cons: None.
Sharpness: 10    Aberrations: 9    Bokeh: 10    Handling: 10    Value: 10    Camera Used: Fujifilm X-E1   

I bought this lens recently on E@ay, it's the last iteration of the lens before it was re-labelled as Pentacon. It has the weird button to control the aperture, bit stiff but it;s working fine as I can control aperture by both the button and the ring. beautiful lens though it has some oil on the blades but the focus ring is smooth, the glass is OK (clean with some dust and bit haze). here some pics taken by the lens 3,4,5.(SOOC).
Junior Member

Registered: June, 2013
Posts: 30
Lens Review Date: February 14, 2020 I can recommend this lens: Yes | Price: $100.00 | Rating: 9 

Pros: Sharpness, Bokeh, heft, Focus swing
Cons: none
Sharpness: 9    Aberrations: 8    Bokeh: 9    Handling: 8    Value: 10    Camera Used: Pentax K-1ii   

≈For the price and it's age, this is a fantastic find. Aperature ring has 'smooth clicks' and the focus swing of 320 degrees allows for really fine focus. I just received this lens and have it mounted with a genuine Pentax M42-K adapter ring which mounts like a charm (no key required). The aperture pin on the back sticks out quite a bit and was binding on removal of the lens - be gentle and with a bit of wiggle, it comes off. In order to use the lens in T-AV mode (aperture set manually on the lens and shutter auto by the body), the lens pin on the mount has to be pushed in permanently by either gluing it, putting tape over it, or what I did.... I bent it with needle nose pliers ever so slightly and pushed it in, so it stays in.
Now the lens works as in aperture priority (T-AV mode) with auto shutter and manual focus. (The alternate was to use the aperture preview button on the base of the lens with a free finger each time you focus and shoot - awkward to say the least)!
Here are a couple first shots... I'm pretty happy for the price to have a ~60 year old lens (slightly older than me), that works like a charm! I can't believe that I'm getting so into vintage lenses on such an advanced body!!! But that's part of the fun of owning a Pentax!

New Member

Registered: May, 2013
Location: Jakarta
Posts: 2
Lens Review Date: December 4, 2014 I can recommend this lens: Yes | Price: $200.00 | Rating: 8 

Pros: sharpness, bokeh, deep color rendering
Cons: price
Sharpness: 10    Aberrations: 9    Bokeh: 10    Handling: 8    Value: 5    Camera Used: K5   

have the preset type with 15 blades(?), M42, this lens can produce beautifull deep color image, and also has all meyer's lens bokeh character
you will not be disappointed to have this lens, highly recommended

samples shots are here:
Inactive Account

Registered: April, 2011
Location: near Berlin
Posts: 9

1 user found this helpful
Lens Review Date: January 24, 2012 I can recommend this lens: Yes | Price: None indicated | Rating: 10 

Pros: build, bokeh, size, weight, sharp stopped down, fast, fluid aperture settings possible
Cons: sharpness wide open, needs good hood, 1.1m close focus distance
Sharpness: 9    Aberrations: 8    Bokeh: 10    Handling: 10    Value: 10   

This a gift from my grandpa. At first I was bit unsure if this small lens is really worth to adapt it. But it is! I had an adapter and a good hood at home, so I tried and I was surprised positively - nice handling and focussing, good IQ stopped down a bit, perfect bokeh and it is sooooo tiny! It really is nothing for closeups but perfect for potraiture. Stopping down will also help to eliminate some CAs. I think it can survive another 40 years!
Junior Member

Registered: September, 2009
Location: Galati on Danube-Romania
Posts: 33
Lens Review Date: November 6, 2010 I can recommend this lens: Yes | Price: None indicated | Rating: 10 

Pros: Time resistance (40 years old, aprox.), very good sharp and bokeh
Cons: Difficult precise manual focus without split focus screen

I used this lens in the slide Era (1976-1989 for me) on Zenit E Russian camera. A great repro of colors and very fine bokeh and sharpness.
I all agree with rfranner script on this lens. A particular optical quality is the lent decrease of clarity in front and back of the plane of focus in comparison with new lenses for digital. That means if you don't focus perfect on the subject, the blur is not intense and you can recover the clarity in p.p. Is a very good impression of the real sight in the photos taken with it. Examples are more than thousand words:

There are some p.p. but if there is no good info in original shot, you can't obtain a good p.p.
I take shots with my Samsung GX20 and Pentax K7 and this lens has a good color rendering, good contrast (specially with K7 with 0 adjustments sliders).
Others examples:
Inactive Account

Registered: January, 2010
Location: Cookstown
Posts: 7
Lens Review Date: January 23, 2010 I can recommend this lens: Yes | Price: $100.00 | Rating: 9 

Pros: Tactile rendering; outstanding bokeh
Cons: needs post production to really shine, fully manual operation

I see one of you has stumbled on one the best-kept secrets: the outstanding performance of Meyer Optik lenses. This East German brand (long defunct) laboured under the shadow of Carl Zeiss Jena, even in its own country. Besides the lens you're reviewing, I've managed to collect the 50mm f1.8, yet another 100mm 2.8 (its predecessor, the Trioplan, a triplet: very different rendering, spooky bokeh, less smooth, but funky), the 135mm f2.8 (MONSTER bokeh!), and the 200mm f4. They're all gems, and very under-rated. By the way, the circularity of the diaphragm ensures round instead of polygonal out-f-focus highlights; but it doesn't otherwise affect the bokeh. That depends on the lens design and coatings. In general, aspherical elements trade off distortion and clarity for bokeh.
Compared to an excellent modern lens, in general, you'll find the rendering of the Meyer family somewhat bland (often easily fixed with auto contrast in Photoshop) and in need of sharpening. Also, the telephotos can be somewhat prone to flare.
I find that they produce incomparable bokeh, and it seems to survive the sharpening process in PP (whereas the output from modern lenses quickly gets grainy and harsh).
At the end of the day, when I want to feel the texture of the subject just by looking at the image, I reach for a Meyer Optik lens more often than not.
They're still a relative bargain on ebay (unlike Carl Zeiss Jena, which now commands inflated prices); but make sure the version of the lens has a manual-auto switch for use (in fully stopped-down mode) on your DSLR.
Senior Member

Registered: July, 2008
Location: France
Posts: 128
Lens Review Date: January 16, 2010 I can recommend this lens: Yes | Price: None indicated | Rating: 9 

Pros: Very well built but not heavy, sharpness, color rendering
Cons: Well, M42, so no f/stop control with the camera dial ...

I bought this lens quite by mistake, mostly for curiosity because it didn't cost too much and i wanted to test it against my SMC Takumar 105/2.8 ...

Well, after a few shots i changed my mind. The lens is incredibly sharp, presenting a very good contrast, although not as high as a Zeiss lens, and has a little cooler color rendering when compared to other Pentax lenses (notably, the 105/2.8).
Nevertheless, it's a joy to use on my K10D, since it is the only M42 lens from my set that perfectly meters with my camera. The bokeh is really pleasant too, most probably because of the high number of diaphragm blades. And the lens is perfectly usable wide open, IMHO, if you keep in mind the razor thin DOF at f/2.8 ...

Definitively, a good companion for my SMC Tak 105/2.8 ...
Veteran Member

Registered: August, 2008
Location: Greece and UK
Posts: 309
Lens Review Date: October 19, 2009 I can recommend this lens: Yes | Price: None indicated | Rating: 8 

Pros: Well made,solid, sharp
Cons: Needs a good hood. Strictly for MF

I bought this lens for 10 in a Charity shop a few years ago. It had the start of some fungus on the front and rear elements but was otherwise in good condition. I found it very easy to take apart and clean (lots and lots of unscrewing) but the results have been well worth it.

I did run a comparison with the SMC 135 f/3.5 and, in my opinion, this lens outshines the Pentax in all areas - especially the bokeh - probably due to the 14 blade aperture as against the 6 blades of the Pentax. Strangely, although it's not multi-coated, the lens has never shown much flare or CA and compared to the Pentax, produces a somewhat 'cool' image tone. It's also pretty sharp wide open which becomes excellent if stopped down a little.

This is the earlier 'Zebra' version (it's name becomes obvious if you look at it) which spawned a long line of popular lenses such as the 'Pentacon'.

I would give this lens a worthy all round 8 and IMO is worth buying if you can find a good dust/fungus free copy.
Add Review of Meyer-Optik Orestor / Pentacon 100mm f/2.8 (M42)

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