Soligor 100mm f2.8 Macro Same Formula As Vivitar 90mm f2.8?

[justtorchit]

I just acquired a rare bird, the Soligor 100mm f/2.8 Macro. Few threads exist here on the forum discussing this lens. I have seen some mentions elsewhere like Pentax Forums similarly trying to figure out more about this lens. Fortunately, this sale included the original box (no user's manual or literature though).

A couple of initial observations. The previous threads here mention poor build quality. The lens I received looks like New Old Stock. It's beautiful and I can't find a mark on it. Yet, the focusing barrel is a bit loose. Annoying. The focusing action itself, however, is buttery smooth, like my Soligor 28/2, 35/2, 55/2.8 and 135/2. So I'm pleased it isn't rough or barely acceptable as some users experienced. Perhaps this copy is the same copy the previous poster mentioned with the loose barrel who claimed he returned 2 copies fo such reasons.

Now to the optics. I have a basic understanding of optics here so this is partly what I am asking. The specs list this lens as having 6 elements in 4 groups. Similarly, the Vivitar 90mm f/2.8 1:1 Macro also is listed as having a 6/4 optical formula. To be clear, I am not referring to the Series 1 macro lens. I am referring to the lens that natively goes to 1:1 and can be found rebranded as Elicar, Panagor, Rokunar, and other brands including Soligor! Have a look at the two optical formula drawings pulled from the lens' respective boxes. The Vivitar was pulled from an eBay listing where the box was at an awkward angle so I warped it back to 'flat' in photoshop. The similarity is striking, if not identical, to me.

Interestingly, the Soligor only goes to 1:2 reproduction, unless you mount the 1:1 adapter, which contains no optics and is merely an extension tube. Is it possible this lens is a precursor to the 90mm which perhaps employed a new helical design to allow the optics to travel more distance giving the full capabilities without the need for an extension tube?

Some other notes: I think the general consensus is that Komine made the Vivitar 90mm f/2.8. The Soligor 100mm, however, has a serial indicating it was made by Tokina. The physical appearance of the Soligor 100mm reinforces the Tokina connection as it bears such resemblance to the Vivitar Series 1 90mm f/2.5, which we know to be made by Tokina as well. The 1:1 adapter for the Soligor is a spitting image of the 1:1 adapter for the Vivitar 90mm though the Soligor contains no optics, whereas the Vivitar does. Again, just musing here.


Soligor 100mm f/2.8 Macro Optical Design vs Vivitar 90mm f/2.8 1:1 Macro Optical Design









Soligor 100mm f/2.8 Box and Specifications



Vivitar 90mm f/2.8 1:1 Macro



I'm interesting in what you all think.

[vivaldibow]

Congratulations. From the literature you posted, the optics are very similar, which means should be slightly worst than VS1 90mm 2.5.

I got a mint copy last year so didnt jump on this one. I was surprised there were very few bids.

[justtorchit]

[D1N0]

Never heard of the Soligor/Tokina 100mm 2.8 before. It is a double gauss design but with significantly thicker second and fifth element than the Komine. Should be more contrasty.

It is probably the precursor of the Bokina, which was made from 1977 to 81 http://allphotolenses.com/lenses/item/c_113.html Your copy has a 1975 serial number.

[vivaldibow]

[Gardener]

[55]

[vivaldibow]

[vivaldibow]

[justtorchit]

[55]

[kymarto]

The double gauss formula 6/4 is used in literally hundreds of lenses. While all 6/4s share some characteristics in terms of the look, there are huge differences as well depending on the curvature and thickness of the elements and the glass formulations used.

[justtorchit]

[justtorchit]

Went outside yesterday to test this lens out only to find a cloudy, dull sky. The sun occasionally peaked through but even then it was mostly veiled by thin cloud cover. I captured the following images on the Nikon Z 7 using an M42 adapter. None of these images use the 1:1 tube. On the edited images, I tweaked a number of things like I would any image from even modern lenses, bumping contrast or saturation, etc. This seems to be a very capable lens.


Unedited - @ f/2.8



Unedited - @ f/5.6



Edited in Adobe Camera Raw - @ f/2.8



Edited in Adobe Camera Raw - @ f/5.6



Edited in Adobe Camera Raw - @ f/2.8



Moxxi - @ f/2.8



Leeloo - @ f/2.8

[calvin83]

This is one of the lens I am looking for in the past. Looks it is a capable performer.

[Blazer0ne]

...

[Ernst Dinkla]

Considering the optical parts in the Soligor 100mm versus the parts in the Tokina 90mm 2.5, there is a lot of difference. The Tokina has 8 elements 7 groups, where the front Double Gauss is an 6/5 Ultron type. That Ultron part moves as a unit in focusing while the 2 extra lenses at the rear do not not move at all. The macro adapter adds another 3 elements 3 groups lens system to that. The Soligor is more the plain 6 elements 4 groups Double Gauss/Planar type. The Tokina is excellent at 0.5x and up to infinity, 1:1 covered by the macro adapter, all with a smooth bokeh.

[justtorchit]

[Ernst Dinkla]

[justtorchit]

[D1N0]

Overall it reminds me of the Vivitar 90mm 2.8 Komine version more (I have it in Panagor)

Here is a sample:
What are you looking at? by The lens profile, on Flickr

[55]

I'm bumping this old topic to revise some repair advice I gave a year ago regarding looseness in the Soligor C/D 100's focus barrel:

To begin, for access to the screws which hold the focus barrel in place, remove the rubber focus grip. Seven screws will now be exposed.
The lower three secure the distance scale to the focus barrel, and the upper three (green circle) secure the external focus barrel to the inner focus ring. And the last, larger screw is a focus throw stopper (not shown).


#1



In 2021 I wrote that I loosened all the focus barrel screws, pushed the focus barrel as far forward as it would go (without any further disassembly) and then retightened the screws.
That did help temporarily, but I now realize that was a mistake.

A couple days ago I took out my Soligor and the focus barrel was more wobbly than ever before!
So I decided to try again to find out the reason.

This time, I wanted to remove the focus barrel to see what's underneath it. These are the steps:

1) Using a friction tool, unscrew the name ring at the front of the lens. Now four screws are accessible.
2) Loosen the four screws in the brass washer, and the upper barrel with reproduction ratios printed on it will lift off.
3) If you haven't already, remove rubber focus grip - or at least fold it upward enough to get access to the lower and mid focus barrel.
4) Loosen the seven screws in the focus barrel and the barrel will lift off. The screws shouldn't need to be removed - just loosened enough to get the pieces free. But be careful with the distance scale screws - they're short and easy to lose.

In the group photo below, the center and right photos show the lens with the focus barrel removed. The green circle and arrow indicate where the focus barrel screws meet the inner focus ring.
That channel is beveled and narrower at the bottom. So for the most secure hold, the focus ring should be pushed down as far as it can go before tightening its screws.

And when I reassemble my 100, I'm going to put a drop of clear nail polish on the focus barrel screw heads to help keep them from potentially backing out.


#2




I use my 100 just occasionally, but it will be interesting to see how long this latest fix will last.
It's surprising to me this barrel looseness is common with this 100. The build and finish quality are excellent otherwise. And I've had no such similar issues with any of my several other first generation Soligor CD lenses.

[RokkorDoctor]

[guardian]

I just bought one of the Soligor 100mm lenses. It came with the original box and the 1:1 adapter.

So far so good with the mechanical aspects. But given the above I have no intention of putting this lens through its paces mechanically. Am being very gentle.

Uncertain how rare this lens actually is. Saw it for US$90. That struck me as rather reasonable. Pulled trigger. Hoping for the best. We shall see.

These do not seem to come up for sale very often. Difficult to get a handle on actual value.

[caspert79]