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Post by belgiumreporter on Jan 14, 2016 10:45:49 GMT -5
On one of my recent photo shopping tours i came across this Helios 135/1:28 its in as new condition and only cost me 5€. I assumed it was a Russian lens, but the JCII sticker should have warned me also the made in Japan on the front ring could have rung a bell. After a brief google it became clear that some japanese factory was desperate enough to use the Helios name as some sort of quality label to put on their otherwise no name lenses. I can't complain about the build quality as it is better than most Russian stuff i've held, optically there isn't much to brag about. It is indeed 2.8 and some people seem to be very pleased with this lens and mostly mention you can't go wrong for the price they've paid for it. I must admit i've seen worse, when mounted on a mirrorless it'll probably give you some pleasing results. However the same 5€ bought me a pristine super takumar 200mm 1:4 now it might not be very scientific to compare this to the helios but just to show even 5€ can get you real quality versus "pleasing" results i made this comparison. The set up Helios@2.8 ( et 5.6 it did inprove but not by much) Super takumar@ 1:4 And for something completely diffrent, the nikon P600 at 900mm-5,6 1/125 sec handheld if you like tele shots the p600 really kicks a** (i paid less for the p600 than the NX100 setup !)
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Stephen
Lifetime Member
Still collecting.......
Posts: 2,718
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Post by Stephen on Jan 14, 2016 12:52:20 GMT -5
The Helios brand was owned by Dixons in the UK, bought from the Russian distributors, and still used on binoculars etc.. The name came on loads of items, and the 135mm F2.8 is a generic type from one of three makers in Japan. They are all the same elements design +/- a bit, and were a very sound design, but made to sell cheaply.
The grinding and polishing was to good standards, it takes as long to gring a good lens as a bad one, but the glass was a cheaper grade with more inclusions and bubbles. After grinding the optical surface curves, which should share the same optical centre point if well ground, on both concave and convex surfaces, the lenses are edge ground to match the optical centre line, but cheaper lenses were ground to a theoretical line, not adjusted to be perfect. Some were not even edge ground.
The cheaper ones relied on tolerances to allow the glass to be added to the metal, or plastic, support of the lens body.
A more expensive lens would have the edge ground accurately and tested, and then on assembly be bedded in to collimate the element optically to the true optical centre line. Each added element would be hand assembled and adjusted to the true line and correct distance of each elements focus point. The exact position of each element varied a bit on each quality example, the assembly allows it to get the perfect line up.
A well adjusted lens has any remaining aberrations evenly spread around the lens field, and a perfectly straight line optically through the lens centre.
The cheap lenses just dropped the elements into the barrels and relied on a quality check to verify the lens focused over the correct range. Really bad ones were returned to correct major defects.
So the cheap lens has the same elements but offset or kinked optical paths, given away but uneven abbreviations around the optical field. They may also have less optical blackening and baffling inside the lens, compared to expensive versions.
These problems only really show at max aperture, stopped down to mid range even a poorly made one will work, but nowhere as good as a properly made top makers lens.
However you can strike lucky, and find a nicely set up cheap lens, or get a brand like Vivitar, who sample tested all lenses, demanding a lower failure rate. Most cheaper importers had no testing, they took what the makers supplied. The saving grace of the whole area was that the Japanese made good lenses anyway, not quite true till recently for Korea or China.
Stephen.
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Stephen
Lifetime Member
Still collecting.......
Posts: 2,718
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Post by Stephen on Jan 14, 2016 13:16:26 GMT -5
An extra "bit of fun" is to take the cheap 135mm apart and assemble it correctly, you don't need an optical bench, just a bit of engineering sense, and a small laser (pointer), and the ability to shine the laser down the measured centre line, without the glass elements in place, on to a centred target, and then adding and adjusting the glass elements, to keep the laser spot unmoved on the target. It does not allow checking each parts true focus, but unless the grinding and polishing was awful, this can be taken as reasonable.
The re-assembled lens should deliver much better open aperture performance. Add black paint to any interior shiny surfaces and the edges of the grinding on each glass element.
The other thing you can do is make a true "soft focus" lens, not by Vaseline or filter, which just gives "out of focus" effects.
It is done by moving the aperture iris forward, and moving the front element forward a bit on packing. The lens may not focus to infinity, but will take very good soft portraits, with sharper centres, and the proper soft look that Leica got. You can experiment with moving the rear element group back a small amount as well.
Stephen.
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Post by julio1fer on Jan 15, 2016 18:24:27 GMT -5
The Tak 200/f4 is a great lens. I also would have assumed that the Helios was a Soviet piece.
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Stephen
Lifetime Member
Still collecting.......
Posts: 2,718
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Post by Stephen on Jan 16, 2016 11:18:28 GMT -5
Checked up on the Helios Brand, and it was the Russians own brand till the collapse of the USSR in the late 1980's. The ownership remained with the Russian importers to the UK after this, and the company, Technical and Optical Equipment, (TOE)Ltd, retained it after the Russians stopped control directly of TOE(ltd). They attempted to run the company in the UK without the Russian supplies, and turned to branding bought in lenses, binoculars and microscopes. This continued till the closure of TOE(ltd), and they were a major customers, Dixons, the UK retail group, took over the name and the goods under the Helios brand.
The Helios lenses in the main come from Tokina, but various other makers seem to have been used at times. To confuse matters, the Russians still make Helios Brand lenses, but clearly marked as to source. The brand features on Binoculars in the UK as well, Optical Vision ltd., has a range all branded for Helios. They appear to all be Chinese now or Japanese for the camera lenses. Stephen.
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