Is the Chinese Biotar any good?
Disassembly and Cleaning
Hai’ou (accent mark to aid pronunciation, sounds like Hai O), 海鸥 in Chinese, means seagull. And there is a seagull symbol on the name plate. This is one of several Chinese camera brands available during the pre-economic reformed days in China. Today we have many more Chinese lenses, like the now famous 7Artisan 50mm f/1.1 in Leica M mount. But back in those days, the Seagull brand was one of the few that existed, and exported in limited quantities. I had seen a few Seagull cameras and lenses in my youth, not many though, as they were thought to be of poor quality. Back then everyone had a Yashica Electro 35 GSN or some variant of that.
A dead Seagull (1966), said to be a Minolta SR-2 clone. The Chinese inscription is 海鸥 written in calligraphic style. The original camera was said to be called Shanghai Model 7 in 1964, renamed to Seagull DF in 1967. DF = Dan Fan 单反 (Chinese) = SLR (English).
The Chinese Biotar
The Carl Zeiss Jena Biotar 2/58 is a classic lens design that dates back all the way to the 1920’s. It is famous for its sharpness and unique bokeh. The Biotar was developed by the famous lens designer Dr. Willy Walter Merté for Carl Zeiss and is a six element lens with asymmetrical outer elements, a variant of the Double Gauss design for higher performance and increased field correction and speed (Cheyenne Morrison).
Optical formula of the Biotar 58mm f/2, 6 elements in 4 groups
Probably the most famous, cheap and readily available 58mm f/2 Biotar is a Soviet/Russian copy – the Helios-44 in its various guises (44, 44-2, 44-M, for example). That would be a story for another day.
The Haiou-64 58mm f/2 is thus a copy of a copy – the Russian Helios 44 being a copy of the German Zeiss Biotar, and the Chinese copied the Russians. The Biotar type lens is said to be very good, this would be an interesting lens to play with. From the look of it, this lens has mono-coating and should flare like mad, so the use of a hood is probably mandatory.
It seems the 64 in the name of the lens signifies that the design is of 6 elements in 4 groups.
Why not Minolta?
Chinese web sources reported that the Shanghai Camera Factory in 1964 made the Shanghai DF based on Minolta SR-1. And in 1966, it made the Seagull DF based on Minolta SR-2 (Reference in Chinese). There was no mention of Minolta’s assistance on the early Seagull cameras and lenses. The later DF-300 (based on the Minolta X-300), however, was the product of Minolta-China cooperation.
DF-300 – licensed by Minolta (photo: Raymond Mok)
So I have a question: the Chinese copied the Minolta cameras (SR-1 and SR-2), including the lens mount (SR mount), then why not copy the Minolta Auto-Rokkor 55mm f/1.8 or other similar Auto-Rokkor normal lens?
My friend Henrik Robeck postulated the Zeiss Biotar is much older, with patents lapsed, and as all German patents became null and void after WW2 it was thus easy to copy. Adding that the type of optical glass was also easier to produce as both the type of optical glass was known and copied (the Russians got the whole glass works) made it easier for the Chinese back then. Anders Lattermann added that it was well known that the Chinese and the Soviet were cooperating well at that time and probably offered a way to get Soviet lens designs, tools and knowledge.
I also postulate that there was a conscious decision not to copy Soviet SLR cameras (the Zenit and Zorki, for example), but to copy Japanese SLR cameras.
Note on the lens mount
The Minolta manual focus lens mount is frequently referred to as the MC/MD mount on the net. Strictly speaking, the lens mount is SR, while the MC is the designation of the lens type. And from functionality there are 4 lens types: Rokkor, Auto Rokkor, MC Rokkor and MD Rokkor. Rokkor lenses are preset type, Auto Rokkor lenses have automatic diaphragm, MC Rokkor lenses are with meter coupling (required for SR-T camera onwards) and MD Rokkor lenses allow for shutter priority and program modes (required for XD and X-700).
This Seagull-64 would belong to the Auto Rokkor type.
See http://minolta.eazypix.de/lenses/index.html for the complete listing of the Minolta manual focus lenses; scroll to the later part of the page and find a wealth of information on the various types and sub-types of Minolta SR lenses. For example, the last Minolta manual focus lenses were simply MD lenses, the Rokkor designation was dropped.
Other Chinese Lenses
I did a search on the internet. Chinese webpages were overall a rather disappointing experience. Not much more than brief mentions of cameras without talking about lenses, and lots of nationalistic ranting.
There was, on MFLenses forum, a rather impressive chart:
I was quite disappointed that on the usual ebay, Taobao (淘宝) not much else turned out on Chinese lenses. Almost nothing except the Haiou-64 that could be counted vintage. Notable ones (in SR/MC/MD mount) are:
- Chrome-nosed Haiou-64 (Auto Rokkor type, subject of this write-up)
- Black-nosed Haiou-64 (Auto Rokkor type, rubber grip)
- Seagull 24mm f/2.8 (MD, rather rare)
- Seagull-710 50mm f/1.4 (MD)
- Seagull-610 50mm f/1.8 (MD), of significant plastic construction
- Seagull 28-70mm f/3.5-4.5, that looks like a Cosina (MD)
Attempt to locate any of those in the chart above was proving futile. Perhaps another trip to Shanghai Starlight Photographic City would be required to find more Haiou lenses.
My friend Raymond Mok has graciously provided photographs of the Seagull 24mm f/2.8 and Seagull-610 50mm f/1.8 (and the above DF-300 film back).
Seagull 24mm f/2.8 (Photo: Raymond Mok)
Seagull 24mm f/2.8 (Photo: Raymond Mok)
Seagull-610 50mm f/1.8 (Photo: Raymond Mok)
This is my first Chinese lens, not counting those modern Nikkors that are made in China. My first encounter of this lens was in Inner Mongolia, in 2017 at 塞上老街and a copy of this lens along with a Seagull camera was offered to me at around $30. Too much, as the lens had lost its rubber on the FR (clearly a newer version of this lens), and the camera was barely functioning. I was also looking for one in Shanghai Starlight Photographic City 星光摄影器材城 at Luban Lu 鲁班路 in 2018. Again prices were not to my liking.
I finally got this lens as part of a relatively large estate acquisition in May 2019, mounted on a (dead) Minolta XE-7.
The lens was in relatively poor shape when it arrived – rough focusing action, iffy aperture stop-down, and fungus. The rough focusing action and fungus were solved quickly, the iffy aperture stop-down was not be fully resolved – for modern mirrorless use it was not necessary to do so, but if this lens was to be used on an SLR, then more work needs to be done on the aperture mechanism. There could be something in the aperture mechanism that is defective.
After cleaning the lens is quite sharp! I took it out with the Nikon Z 6 to my neighbourhood to test drive it, limited shooting. With a rubber hood attached, I took some shots and the following are my conclusions:
- The lens is sharp
- The colour is weak
- Boosting colour in LR brings it back to more acceptable performance, or perhaps the profile can be set to saturated when shooting?
- Straight B&W conversions give good results
Straight conversion without adjustments
Adjusting “presence” and selective saturation enhancement brings the lens to more modern level.
Straight B&W conversion
Adjusted for shadow and darkened sky
At f/2 there is significant vignette, more or less gone by f/4. Wide open the lens is somewhat soft but acceptable, and sharpness improves by quite a lot stopping down.
Perusing flickr, I found that the lens is very sharp, and capable of giving the famous bubble-bokeh. Need to do coerce this bokeh out from my copy!
I am an engineer by training, I enjoy photography, love listening to music, and am addicted to scuba diving; hence the nick diediemustdive. You are here not to read about me, but about the lens I am about to describe, but then you just might be interested to know a little more About Me. Go ahead and click on that link, if you will.
All information in this blog is meant for sharing of experience and not as instruction, and is no substitute for diligent learning and assessment of competence. I have messed up my fair share of lenses, and will not be held responsible for any damage caused in the reader’s venture into this fascinating world of mechanical and optical marvel.
You should be conversant with lens repair techniques; beginners should read my earlier blog posts – the Lens Repair series (Lens Repair (1): Some Thoughts, Lens Repair (2): Major Parts of a Lens (Manual Focus), Lens Repair (3): Working from the rear…, Lens Repair (4): Coming from the front, Lens Repair (5): Helicoids) and Richard Haw’s excellent write-ups (Camera and Lens Repair Essentials, Best Practices (part 1), Best Practices (part 2), Best Practices (part 3) and Working with Helicoids).
As in all my disassembly, I would try to find a repair manual, exploded diagram or internet tear-down notes. I did find an exploded diagram, that was in poor resolution, and fairly complete tear-down instructions (albeit in Chinese).
Exploded diagram, resolution rather poor due to poor original scan.
First review the mechanical features of the lens.
Slot at the name plate suggests the approach should be from the front.
Rear mount has no screws. The lens external stop-down lever is to the right – a feature added to Auto Rokkor lenses when quick return mirror was introduced in the camera. There appeared to be a position for a guide pin at the mount (black spot at the bottom).
And there is a single set screw, I did not explore the function of this set screw.
This screw is the infinity stopper for the FR.
Most visible features have been described, so the next thing to do would be to proceed with the disassembly.
Using a lens spanner wrench to access the 2 slots on the name plate. The make was crude; with some alcohol and some rough sounding movement the name plate came off. Four screws that appeared to hold the filter ring…
… turned out to be holding the filter ring and the OU/AU. The filter ring slides out at the rear.
The (optical unit) OU/AU (aperture unit) all in one piece – to the right is the stop-down lever.
Replacing these two (filter ring and OU/AU) we will need to align the aperture mechanism lever into the stop-down aperture setting spring-loaded slot.
The helicoid key (HK) screws are access from the front. Turning the focusing ring (FR) to minimum focus distance (MFD), the HK screws can be removed.
HK removed. Mark orientation.
Before removing focusing ring helicoid FRH/OUH optical unit helicoid assembly from the barrel helicoid (BH), measure the length at MFD.
Remove the infinity stopper screw. Second time seeing this (first was a Rollei QBM lens), and the additional un-threaded part makes it easy to recognize such screws.
~7 turns CCW, separation at 3m mark.
The helicoid guide posts are a pair of plates with slot screwed in at the rear. Reviewed position of OUH in relation to FRH at MFD – would be position after installation.
I removed the helicoid guide plates, which was not necessary. CCW removal from back of FRH. Separation marked.
3 screws were removed to separate the BH from the mount.
Left is the BH, right is the rear mount. Aperture control curve is at the top on the AR (on BH) and there is a small ball bearing for aperture detent (~265˚). Aperture actuation mechanism is with rear mount.
External stop-down lever, has to be removed if the AR is to be removed. The AR is on the BH.
The lens disassembled
Proceed to clean the FRH, OUH and BH with lighter fluid and scrub them clean. Re-grease, and re-install, in the reverse order. This is where the earlier markings of separation point is important – the separation points are also the starting points. If you did not record or mark the points, there will be many trials to get the lens back into the correct order!
Optical formula as reference.
The FOU/AU/ROU. Front optical unit, aperture unit, rear optical unit.
FOU removed via external slots. The screw on the Aperture Unit is to loosen the inner retainer for adjustment of minimum aperture. Don’t touch the AU screw if you can help it.
FOU, inner slots of retainer to access E1.
FOU rear view, E2/E3 commented.
Front view of AU. Outer retainer is the for the aperture assembly, inner slotted retainer to adjust min aperture.
ROU – external retainer removes the ROU.
E6 removed, there is a retainer but was cleaned in-situ.
Dimples to remove E4/E5. Cleaned and replaced. I usually work from inside out; in this case I cleaned E4/E5, replace them, then I proceed to clean E6.
Returning to the front, remove retainer to E1. Flip out E1 and cleaned.
E2/E3 appears built-in, and was cleaned in-place.
E6 was in a real mess, rear view.
After cleaning, simply reassemble the OU/AU, and pop the unit back into the lens, watching out for the linkages and alignments.
All optical elements were cleaned with hydrogen peroxide and then rubbing alcohol. This is after re-assembly of the lens.
Where I can, I will also scrub the lens. Some will even polish the lens, and I had only done so once, on an Industar-50, but found that polishing will also require touch-up paint. So mostly I settle with the soap and toothbrush approach.
The lens was made in the early communist era when the motto was “for the people”. But there were few people who were able to “afford” having a camera, since in communist society everyone is equal and so allocation of resource was based on some other priority, e.g. for news, security, etc. Some of these lenses did make it out of the iron curtain, and in all fairness, the lens performed well, if rough on the edges. A Minolta Auto Rokkor (I do have a couple), for example, are far better made than this Chinese lens. Optically, I do not have a Biotar to compare it with, although I do have a Helios-44-2, and I think this lens is better than the famed Helios.
Seems like a keeper. If nothing else, this is a novelty lens, a Chinese lens, a Biotar. Perhaps I will get some fun out of it whenever my colleagues and friend in China see me using an ancient Haiou-64 lens in front of my modern Nikon Z 6!
That reminds me I need to get my first Singapore lens (a Rollei QBM lens) back in shape for shooting!
Until next time, bye. If you have enjoyed reading this, or if this article has helped you, please write to me.
A few months ago, my page was blocked for no reason, apparently a bot determined that this is a spam page, presumably it went through the reference pages. I panicked as I did not have the write-ups backed up!
Fortunately a mail to WordPress gave me back my blogs…
It taught me 2 things:
- never ever have only an online version – keep a copy on my hard disk (and back them up). I have heard horror stories of people storing their precious photographs online or in the cloud and suddenly lost their entire collection.
- I have to rethink about publishing all my tear downs, numbered over 50 right now.
Tell me what you think.
- （转载）海鸥64 58mm/f2金属标头完改M42 http://vincent-deng0125.lofter.com/post/d3ae6_1439e16
- HAIOU-64 58mm f2 拆解清理 http://hkptparadise.blogspot.com/2018/07/haiou-64-58mm-f2.html
- HaiOu-64 白嘴58 2 MD改M42 http://blog.sina.com.cn/s/blog_702299ab0102wtjb.html
- 海鸥HAIOU-64 58mm 1:2镜头清理http://bbs.camgle.com/thread-724521-1-1.html