[konraDarnok]

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So yea, these things are everywhere now. I bought mine from this guy:

eBay Seller: jrace99: Cameras Photo items on eBay.com

New, in box, like it says.

(I have this coming in the mail yet 58mm Tele Metal Lens hood Shade Screw-in Black HQ 58 mm - eBay (item 370101221059 end time Nov-20-08 17:39:59 PST) )

After the Live.com discount it cost me 151 usd. I don't need this thing, but I've always wanted Über-fast glass. There you go. LBA strikes again. Looks like generic Mac and Cheese for dinner again this week.

First impressions. It's all metal, solid, and well made -- surprisingly compact.

Sharp. A lot of the sample photos I've seen with this lens look hazy. Frankly, they look over exposed or front focused. This copy looks dead on.

It does look like some chromatic aberration -- but no more than the FA 50mm.

So, after finding it in the box on my doorstep to this post 30min later, here's some photos:

[thePiRaTE!!]

It seems quite clearly a Cosina. I have a question for anyone - I'm still not clear where this Cosina falls among the split.

Tomioka manufactured all the x-nons; Yashinon, Cosinon, Rikenon, etc, etc. While Cosina did the Porst Color Reflex. So is this lens the Cosinon with the Tamioka formula or the Cosina named lens also appearing as the Porst? I thought I'd had it all sorted out until I see this one is straight up 'Cosina', not Cosinon as others have been.

[konraDarnok]

It seems quite clearly a Cosina. I have a question for anyone - I'm still not clear where this Cosina falls among the split.

Tomioka manufactured all the x-nons; Yashinon, Cosinon, Rikenon, etc, etc. While Cosina did the Porst Color Reflex. So is this lens the Cosinon with the Tamioka formula or the Cosina named lens also appearing as the Porst? I thought I'd had it all sorted out until I see this one is straight up 'Cosina', not Cosinon as others have been.

The Vivitar Series 1 is identical to this lens (different rubber grip). So you can add that to your list. I've been combing the web myself. It's interesting.


Manual Focus Lenses :: View topic - Vivitar Series 1 55mm f1.2 Pentax K mount, How is it?

[Miserere]

Kelly, reread my post here

In short, this is the Tomioka lens. Cosinon was the brand name of lenses for Cosina (just like the Nikkor lenses for Nikon).

[thePiRaTE!!]

Kelly, reread my post here

In short, this is the Tomioka lens. Cosinon was the brand name of lenses for Cosina (just like the Nikkor lenses for Nikon).

I did have that in mind, I guess I was just still uncertain due to the plain 'Cosina' rather than Cosinon, which I've also seen.

Thanks again Mis for straitening the wrinkles outta my sheets there tho, hehe.


K.

[Gooshin]

havent had a chance to do anything crazy with this lens yet..

this one is from today,

made by the lens, @ F1.2



and one of the lens, taken with a super takumar 35mm F2.0 @ wide open

[Miserere]

Great stuff, Gooshin! I'm sure Tomioka weren't thinking about this when they designed that lens, but hey, who cares?

[thePiRaTE!!]

havent had a chance to do anything crazy with this lens yet..

I'm not sure if its the big buckets of glass that the larger aperture lenses are that entice this, but I had tried a similar experiment with the T*85 when my copy finally came. Thats one mamojammie glass bucket. Sitting there looking curiously at that huge aperture actuating makes the mind think strange things. Your results were quite interesting though, mine were a miss.

[lbam]

havent had a chance to do anything crazy with this lens yet..

this one is from today,

made by the lens, @ F1.2



and one of the lens, taken with a super takumar 35mm F2.0 @ wide open

Good work here ;-)

[Gooshin]

I'm not sure if its the big buckets of glass that the larger aperture lenses are that entice this, but I had tried a similar experiment with the T*85 when my copy finally came. Thats one mamojammie glass bucket. Sitting there looking curiously at that huge aperture actuating makes the mind think strange things. Your results were quite interesting though, mine were a miss.

its definetly mesmerizing

[thePiRaTE!!]

I received the Tomioka Yashinon today and have been giving it a run through.

Of interest - unlike other Tomiokas it seems, the Yashinon is an 8-blader, like the Porst. Its also unique to some others by virtue of a factory sliced rear element, shaped like a 5/6 full moon. This is to make room for an auto aperture pin on a camera body not designed to house that large of a rear element by the looks of things.

Also, while the aperture ring is marked 1.2, 1.4, 2, 2.8, 4... there are actually unmarked incremental stop all the way through to 16, so one can dial in 1.7, 2.4, 3.5... (presumably) if desired. The Porst on the other hand has no half stops and goes straight from 1.2 to 2. This Yashinon, like the Porst, uses a 55m filter thread, where the later Tomiokas use a 58.

Leaves me to wonder if the optics were the same across all models of Tomioka 55s over time.

With all these 50's here, curiousity starts to take hold. I had a mini shoot-out between the Porst 55, Yashinon 55, Voigt 58 and Super-Tak 50, just for the heck of it. I shot a tennis ball with each lens at wide open, f2 and f4 using minimum focus distances.

My notes:

- it was possible to note the 1.2s had shallower depth of field and more diffusion of contrast (and thus lower contrast) while wide open. The 1.2s and VL to a certain extent appeared to render a soft focus sort of effect at this aperture, with both 1.2's, its as though there was no distinct point of focus, just a mild graduation from more oof to less. That is not to say details are not visible, just that they appear diffused.

- the VL58 can focus as closely as the Tak (.45m) while being 8mm longer. This sets the Nokton apart from the pack in several ways. a) Its has a higher magnification factor than the others (1:5.75, not sure of the rest but over 6 for sure) b) It appeared to render oof as dramatically as the 1.2s at minimum focus distances with this closer focus ability, and with a similar amont of diffusion as well. c) VLs DoF was narrowed vs the Tak at 1.4 under these conditions - correspondingly, it was tricker to hit focus correctly, also similar to the 1.2s.

- The 55's at .6m (ish) and Tak at .45m all had apparenty identical maginification given thier focal lengths.

- The Voigtlander and Tak were sharpest wide open. Even with more diffusion at its closer focus range at 1.4, the VL was offering a clear focus point unlike the 1.2s, though the Tak appeared sharper over a wider depth. As a result, the Tak also appeared less dramatic than the rest oof-wise, wide open and was well contrasted and detailed at 1.4. Depending on your intended use, the Tak might be best of the four for certain applications where a gentle diffusion of detail at 1.4 was not called for. It would seem to be a good choice for 3D type shots where the point of focus is clearly defined against the background.

- At all stops, it would be splitting hairs to call the Porst or Yashinon sharper. They render virtually identically in all but oof areas it seems. It was my sense that the Porst is more sensitive to making light rings in its bokeh, where the Yashinon is perhaps less animated in this way, appearing more gentle/soft in oof. More testing will be done.

- At f4, everybody had a respectably sharp rendition. Surprisingly, the Nokton had the most apparent bokeh at f4 among the bunch. Again, being closer to the object would affect this, but it was interesting to see. It was also the sharpest, but there's not much in it by this aperture.

- Mecahnically, there are some clear differences to note. The Voigtlander, and indeed all the modern Cosina lenses I have, have done away with something all the old lenses have over their skins - grub screws that keep the correct tension on parts, holding them in place. This 'cleaning up' is a welcome development. The modern lenses feel more refined and well thought out, less left to chance and more robust. Nothing rattles or creaks, etc.

Overall, I was a bit surprised. The 1.2s are pretty decent, the Tak showed a useful character differing from the rest and the VL had tricks up its sleeve. For all the times in the past I'd passed on one of these older 1.2s because of their reputations as soft performers, they've turned out to be pretty decent performance wise after 1.2. Yet, its because of their characteristic rendering at 1.2 that I've finally bought them as a bokeh brush.

It seems at least in a close focus test, you should choose your wide aperture lens based on what its doing for you personally at wide aperture, because once they're stopped down, the lines between all these 50's blurs... err, sharpens to where it would take a computer measuring pixels to tell the difference.

[Gooshin]

Kelly, out of the 50-55's that you tested, which has the longest focus throw?

[thePiRaTE!!]

Kelly, out of the 50-55's that you tested, which has the longest focus throw?

Must be a standard for this type of lens, they all are roughly the same. The 1.2s have an extra 20 or so degrees. I'd guess they were around 240-50, with the VL, Tak (and just because it was sitting there, T*85) around 220.

Out of curiosity, the T*25 is about 340 degrees. For a wide angle, you know its an oddball when... (its the close focus thing).


K.

edit - The Porst & Tomioka focus backwards. Mildly annoying as I'm always fighting instinct.

edit 2 - Is the newer Cosina/Tomioka 1.2 you have consistant with this focus range?

edit 3 - updated my degrees! Thanks Mis.

[Miserere]

Thanks for that write up, Kelly. Very thoughtful and happily lacking in MTF charts

The Porst focuses backwards. Mildly annoying as I'm always fighting instinct.

If by backwards, you mean "the Canon way", then the new Cosinas (and the old ones too) also focus backwards. It's one of those things that annoy me about many old lenses. As a side note, many of the old Tokinas were built so they focused and zoomed in the same direction as the camera they had the mount for, instead of using the one-direction-is-fine-for-all approach of other 3rd party brands. Props to Tokina.

Is the newer Cosina/Tomioka 1.2 you have consistant with this focus range?

I don't have the Cosina with me, but I think it travels at least 1/2 a turn, maybe even close to 3/4. Are you sure you got 110 degrees right? I have the Pentax-A 50mm f/1.4 with me here and it turns about 220 degrees.

[Tokina]

The seller sold many of them for $60! That's insane!