Kobori Koboron 3.5-4.8/24-70

iangreenhalgh1 · Expire: 2014-01-07

I bought this lens by mistake, it had one bad picture and the description simply read ' nice old lens, clean condition'. It only cost 3.20ukp inc postage, so if it's awful, no loss.

The picture, with the red ring at the front made me think it was possibly a Canon FD L 24-35:

Nope, it's a Koboron 3.5-4.8/24-70 made by Kobori.

Can't find any info or samples, has anyone used this lens before?

Minolfan · Joined: 30 Dec 2008 Posts: 3439 Location: Netherlands

That would have been an extreme real steal!
Not a too expensive bet after all. and the dream must have been fine.
Kobori made some nice lenses, may be good.
I have a nice built Sakar 28-105mm in MD mount that is probably made by Kobori, but that one doesn't make me happy.
I hope you have more luck with that one

iangreenhalgh1 · Expire: 2014-01-07

Cheers. I'll post some samples when the rain stops and i get chance to try it out.

Mark · Joined: 01 Dec 2012 Posts: 251 Location: Budapest, Hungary

Those 2 lenses seem to be identical, bad luck. :/ Btw is this name (Kobori Koboron) just a brand or a manufacturer? Sounds funny! Smile

casualcollector · Posted: Mon Aug 11, 2014 3:56 pm Post subject:

Kobori is/was(?) a manufacturer. There are Vivitar lenses made by Kobori and I have a Promaster lens made by Kobori. They are also seen under other labels, including Tefnon.

Some of the lenses are considered quite good. The 28-200 manual focus zoom has received some praise. The 28-70 Promaster that I have used I find good but not outstanding.

I've seen comments on the net that the chairs of Minolta and Kobori sat on each other's boards and that Kobori manufactured some Minolta lenses.

Awaiting Ian's experience and comments.

Minolfan · Joined: 30 Dec 2008 Posts: 3439 Location: Netherlands

I had forgotten that I have a 28-200mm AF Vivitar, made by Kobori.
That lens is good indeed! So there is some hope ..

iangreenhalgh1 · Expire: 2014-01-07

Tefnon and Koboron were house brands of Kobori.

You can spot Vivitars made by Kobori by the 77xxxxx serial number.

I have that 28-200 as a Tefnon, it is surprisingly good, tests have shown it to be better than the Kiron 28-200 and the other 28-200s of that time.

I'll try to shoot some samples with my Koboron lens this week.

iangreenhalgh1 · Expire: 2014-01-07

I tested the Koboron today. Immediately I was struck by how the thing suffers terribly from veiling flare - just the brightness of the sky in the top of the frame is enough to cause severe veiling flare! This is a lens that needs a hood, sadly I don't have a 67mm hood. I have ordered one and will repeat the test, but without a hood, the contrast is very low and the lens is hyper-susceptible to flare.

24mm setting,wide open:

100% crop from centre:

24mm setting, 1 stop closed:

100% crop from centre:

24mm setting, 2 stops closed:

100% crop from centre:

50mm setting, wide open:

100% crop from centre:

50mm setting, 1 stop closed:

100% crop from centre:

50mm setting, 2 stops closed:

100% crop from centre:

70mm setting, wide open:

100% crop from centre:

70mm setting, 1 stop closed:

100% crop from centre:

70mm setting, 2 stops closed:

100% crop from centre:

Quite interesting results - contrast is poor, colours a little muted, but sharpness and CA control are both pretty good I think. Wide open it's not that sharp, but acceptable, a tiny bit of visible CA but nothing to worry about. Closed 1 stop, it gets quite sharp and the CA goes, closed two stops and it's sharp.

It's sharper at the 70mm end and the contrast is better at this end too. The 24mm end looks to be the weakest.

Distortion looks pretty mild, I don't see any strong barrel distortion at the wide end or pincushion distortion at the long end. There will be some distortion of course, but it isn't noticeable to me in these test shots so I expect it won't be a problem.

All in all, it's not that bad at all, I need to try it again with a hood.

cyrano · Expire: 2016-12-30

A hood should make a difference but it doesn't look like it will make a great deal of difference. I don't think it's very good at all I'm afraid.

SXR_Mark · Joined: 12 Jun 2010 Posts: 506 Location: England

Wow, that is really bad.That lens must have really ineffective AR coatings. It reminds me of my uncoated dialytes! At least with the dialytes the focal length was large so I could use a really deep hood. With 24mm FL I would be surprised if a hood could be made deep enough to rescue its performance. For what you paid it was worth a punt though.

iangreenhalgh1 · Expire: 2014-01-07

The flare is worst at the wide end and not that bad at the long end. The glass is clean, it's multi-coated, so must just be a case of poor coatings and/or poor internal light baffling.

Fixing the contrast and sharpening and the results look okay, although the 24mm end is rather less good:

24mm, 2 stops closed:

70mm, 2 stops closed:

cyrano · Expire: 2016-12-30

I've just seen the price and with an effective hood and your pp it can only be described as a good thing.

iangreenhalgh1 · Expire: 2014-01-07

If it had decent coatings, it would be a good lens as the sharpness and CA control are very good, but the contrast and flare are very poor.

I did a second test on a closer subject. Sun was directly behind me back but there was still a lot of flare from the bright chrome.

24mm setting, wide open:

100% crop from centre:

24mm setting, 1 stop closed:

100% crop from centre:

24mm setting, 2 stops closed:

100% crop from centre:

50mm setting, wide open:

100% crop from centre:

50mm setting, 1 stop closed:

100% crop from centre:

50mm setting, 2 stops closed:

100% crop from centre:

70mm setting, wide open:

100% crop from centre:

70mm setting, 1 stop closed:

100% crop from centre:

70mm setting, 2 stops closed:

100% crop from centre:

Again, the sharpness is good, wide open it is acceptably sharp, 1 stop closed the sharpness is good and 2 stops closed it is very good, with the 70mm end being a bit sharper than the 24mm end.

The flare and low contrast, however, is very poor and this is worse at the 24mm end than the 70mm end.

iangreenhalgh1 · Expire: 2014-01-07

I did some PP to these samples and the result is not bad realy:

24mm setting, 2 stops closed:

100% crop from centre:

50mm setting, 2 stops closed:

100% crop from centre:

70mm setting, 2 stops closed:

100% crop from centre:

iangreenhalgh1 · Expire: 2014-01-07

Just to give an update - the fault was a mysterious greasy deposit on the sensor of my NEX-3. Once cleaned off, the contrast returned to normal and this lens is a really good performer.

Wadidiz · Joined: 28 Dec 2016 Posts: 36 Location: Stockholm, Sweden

I received a Koboron 24-70mm/3.5-4.8 in a package I bought and am surprised by the performance. It is in top condition, is all metal/glass/rubber, feels very precise & smooth and gives better-than-expected pictures. I tend to only use fixed-focus lenses but I'm actually starting to carry this instead. This photo is from my window, shot wide open at 70mm, ISO 250 on Sony A7. Will continue to test.

uddhava · Expire: 2021-06-21

That did seem like an unnatural amount of flare.
Glad you figured out the problem and every thing is good.
Anxious to see a few improved shots.

devinw · Joined: 19 Aug 2016 Posts: 207 Location: Portland, OR

I was going to say.. It sure seems like there is a hazy deposit on one or more of the elements. Glad to hear you got it fixed up.

Wadidiz · Joined: 28 Dec 2016 Posts: 36 Location: Stockholm, Sweden

uddhava · Expire: 2021-06-21

Wadidiz · Joined: 28 Dec 2016 Posts: 36 Location: Stockholm, Sweden

Another shot from my window with the Koboron. (I noticed the spots on my A7 sensor.) I'm surprised that I can find out almost nothing about Koboron except they apparently made lenses for Vivitar and Minolta and the not-so-encouraging photos earlier in this thread. The lens is somewhat heavy but I can't find any plastic that adds to the weight. Very solid and precise feel, focus and focal-length shift.

bmwtraveler · Joined: 07 Aug 2010 Posts: 23 Location: Bakersfield,Ca

That was the house brand for Cambridge Camera Exchange,New York,good dealer in the 70s,went down hill later,B & H lives there now,they also sold a SLR I think as the Lindenblatt KL-2,designed by Topcon,Cima took over from Topcon

teapeng · Joined: 20 Jan 2017 Posts: 1

@Wadidiz, how do you attach this lens onto the A7? Which adapter were you using? I found a dirt cheap of this lens, thinking of buying it. Vintage lens just look sexy.

Wadidiz · Joined: 28 Dec 2016 Posts: 36 Location: Stockholm, Sweden

juanpabloalvarez · Joined: 18 Mar 2024 Posts: 3

Hello, is there still someone here in 2024? I have a Tokina 24-70 identical to this Kobori. I bought it like new. I plan to try it with a Sony a7IV as soon as I get an adapter.