Minolta AF 3×-1× Macro Zoom
Did I already mention that I'm a macro nerd? Well, this year I was photographing a lot of very small spiders and insects, and I was always fighting to get the necessary magnification. Even when using high-quality equipment like the Minolta 200/4 APO Macro G, combined with the Minolta APO 1.4× and 2× TCs, magnification often wasn't large enough. After cropping the images to the desired field of view, the loss of quality caused by cropping and by the TCs became quite noticable. So I started looking for a high quality lens that allows larger than 1× magnifications without using TCs or other accessories. Fortunately Minolta is making such a lens, the 3×-1× Macro Zoom. In fact, Minolta was the first to make such a lens, and they remained the only one for about a decade. It was only recently that Canon joined Minolta by producing their MP-E 65 mm 1-5× Macro.
Finally, a 3×-1× turned up on eBay, and I bought it. Here are my first impressions:
|AF 3×-1× Macro zoom|
- maximum magnification 1:1 (1×) to 3:1 (3×)
- maximum geometric aperture f/1.7 to f/2.8
- working distance 40 mm to 25 mm
- integrated tripod collar with focus rail
- 7 aperture blades
- non-rotating filter threads, 46 mm size
- motorized magnification setting and rotation
- full metal construction
- comes with front cap, rear cap, macro stand and hard case
The 3×-1× Macro Zoom is a very special lens. First of all, the lens is slightly misnamed, as it is not really a zoom lens. The photographer can not change focal length and focus independently. Focal length varies only slightly with magnification between 52 mm (at 1× magnification) and 45 mm (at 3× magnification). This lens really is a fixed focal length lens with a built-in variable extension tube. The only difference between this lens and, for example, the 50/1.7 is the range of extension. Extension is never zero, meaning that the lens can not focus to infinity. With its minimum extension, the lens focuses at 1:1 magnification, and the working distance is 40 mm. Maximum extension results in 3:1 magnification and a working distance of 25 mm.
The maximum geometric aperture of this lens is f/1.7 at 3× magnification and f/2.8 at 1× magnification. The geometric aperture determines mainly depth of field. However, since extension is so long, the maximum effective aperture is much smaller. It's f/6.7 at 3× magnification and f/5.6 at 1× magnification. This effective aperture determines exposure. The camera knows about the effective aperture and displays aperture numbers from 5.6 to 64. You never see the geometric aperture displayed on the camera, only effective aperture. This means that you can use a handheld exposure meter without a problem. You can set aperture and exposure time as displayed on your external meter, and you will get correct exposure. This is in contrast to other macro lenses, extension tubes or bellows. With these, you have to calculate light loss due to extension manually.
The lens barrel is mounted on a tripod collar with an integrated focus rail. A small knob fixes the focus rail at the current position, and a bigger knob moves the focus rail between −20 mm and +20 mm.
The extension tube is moved by a small motor built into the lens. It does not move fast (about 12 seconds from 1× to 3×), but that's just fine, because it gives you the necessary precision. The same motor is also used to turn the lens between horizontal orientation and turned left by up to 135 degrees. A small switch on top of the lens barrel attaches the motor to either the extension tube or the rotator. You can not move the lens in either dimension manually. The motor is powered by a standard 2CR5 lithium battery, the same type that was used for many Minolta AF camera bodies. Since power is not drawn from the camera, the lens is compatible with even the oldest Minolta AF bodies which do not have motor power supply pins on the lens mount. These appeared only with the xi series bodies, about a year after this lens was released.
The 2CR5 battery is specified to last for 1000 cycles of moving the lens from 1× to 3× magnification and back, and then turning it by 135 degrees 500 times. This means that the battery should last quite long.
There are two principal ways to focus the lens. The first way is to use the focus rail. This keeps magnification constant, but the working distance changes (because the lens moves back and forth). The second way is to use the camera's AF drive, moving the front group of the lens. This keeps working distance unchanged, but slightly changes magnification. There is no way to move the focus group of the lens manually. The magnification scale on the lens indicates the range in which the focus group can move.
The lens has 46 mm filter threads. These are located at the focus group, not on the lens barrel. The outer diameter of a filter should not be much larger than 46 mm, otherwise the filter would hit the lens barrel when the focus group is moved into the lens. So using a filter adapter to fit larger filters on the lens is a no-no!
The lens comes with a macro stand. When you attach the lens to the macro stand, it positions the lens at the right distance to shoot between 1× and 3× magnification. Its three “legs” are spaced to allow the macro ring flash to be mounted at the same time.
The whole assembly comes in a case that not only provides space for the lens and macro stand, but also has prepared cutouts for the 1200 Macro Ring Flash with controller and adapter rings, a camera body, a replacement battery and film cans or other small accessories.
The front cap of the lens does not attach to the filter threads as with other lenses (for reasons explained above), but is lined with a strip of velvet that holds the cap on the lens barrel. While the front cap doesn't immediately fall off the lens, it's quite loose. I can imagine a better design that snaps onto the groove that otherwise holds the ring flash unit.
Using the 3×-1× Macro Zoom
Macro photography is always a technical challenge. The larger the magnification, the more difficult it gets. At 1× and larger magnifications, even very slight movements of the subject will be very visible in the image. Depth of field is paper thin, even when using very small apertures. The small working distance makes it hard to not block all light that falls on the subject. The small effective aperture results in long exposure times in which, again, the subject may move.
The 3×-1× Macro Zoom is definately not a snapshot lens. It requires careful technique, otherwise the results will be just disappointing. Using a tripod is almost a must. At most, you can use it semi-handheld, ie. supporting the lens and using your fingers as a makeshift tripod.
The field of view varies between 36 mm × 24 mm and 12 mm × 8 mm if you're using a film camera, and 23.5 mm × 15.7 mm and 7.8 mm × 5.2 mm if you're using a digital camera with an APS-C size sensor. What you intend to photograph has to fit into this frame. Depth of field is very narrow. At 1× magnification it's at most ± 1.5 mm (at f/54). At 3× magnification it's a tiny ± 0.25 mm.
The greatest challenge is to have enough light for acceptable exposure times. If you're shooting at daylight, you can have the sun neither in your back nor in front of you. In both cases either the lens or the object would block out the sun. Lateral light or diffused light works best with these small working distances. Another option to get some light between object and lens is the Macro Ring Flash 1200 (or its predecessor, the Ring Flash 1200AF-N). The flash tube unit fits onto the 3×-1× Macro Zoom without an adapter ring. Normally when using a ring flash, the strictly frontal lighting gives everything a “deer-in-the-headlights” look. With very short working distances, however, the angle between flash tubes, object and lens is much wider, ie. lighting is less frontal. I expect much more pleasant looking results when using the Ring Flash with the Macro Zoom. I intend to get the Ring Flash soon, and will update this review when I have new results.
The Macro Twin Flash 2400 can not be used with this lens. There is no adapter ring for the flash tube holder to mount it on the lens, and normal filter adapters can not be used (as explained above). Furthermore, the flash tubes don't tilt enough and are too far away from the optical axis to illuminate an object at such short distances.
Here are a few sample images:
- Very solid construction
- Complete accessories
- Front cap should have better design
- Requires careful technique
© 2005 Michael Hohner
|#1: Comment posted by John Ross on August 5th, 2008 - 12:31:59 AM:|
Great images. Thanks so much for the information about this lens. I've been thinking about getting one for several years, but haven't had the guts to invest that much for a hobbie. I photograph flowers, orchids primarily. I've been looking for a lens with more depth of field (of course). This is just the info I needed to make up my mind.
|#2: Comment posted by Beat on March 11th, 2009 - 10:35:54 AM:|
|huuuui, das ist ja ein geniales Ding. Wo kriege ich ein solches
her? Wird vermutlich ziehmlich teuer sein und kaum zu kriegen. Von Minolta eben, inovativ wie sie immer waren.
|Michael Hohner answers:|
|Dieses Objektiv taucht nur sehr selten auf dem Gebrauchtmarkt auf. Neu ist es nicht mehr zu bekommen.|
|#3: Comment posted by Tom Hurst on March 18th, 2009 - 03:36:13 AM:|
|I have this lens and both flashes and use it frequently. I agree it is no snap shot lens but does an excellent job for what it was intended for. Of course you are correct in your entry and accurate. Its sometimes finiky but rewarding. Macro is another world of its own. Thank you Tom.|
|#4: Comment posted by M D Sykes on May 12th, 2009 - 11:49:04 AM:|
|This is a truly awesome lens and has never let me down. I first started with a 9000 back in Dec 85 and progressed to a Dynax 7, Dynax 7D and now a Sony A900. I would not recommend 'hand-held' shooting as you will simply waste the depth of field capabilities of this incredible lens. When 'mobile' I prefer to use the MINOLTA AF 100MM MACRO 1:1 F2.8(32) (with RING FLASH 1200)or MINOLTA AF 200MM MACRO APO G 1:1 F4 (32) (with MACRO TWIN FLASH 2400AF).|
|#5: Comment posted by Halleguen Serge on March 11th, 2011 - 03:11:43 PM:|
|Dear Sir ,I took pleasure reading your article , on this fabulous lens ,I am Minolta , since I bought a 9 xi body , ( i was canon last one was T 70 the first one a Ftb ql in 1970) I enjoy doing macro , insects and spiders mostly ;last years as I was taking a picture, in harbour , my bag , turn on the side and my 2,8 /50mm sony fell in the mud and salt water;Now , i am looking to upgrade to 100mm sony 2,8 .As I read this lens is more reliable , than other brands in sony mount . What do you think ; which other lens would recommend?I Like the Makro plannar 2/100mm but not in Sony mount , and expensive ;to finish , I am retired now , and I wanted to tell you that reading your article is like a poetry , with full of precision, like your photos and I like that keep on (people don't even know what they have in their gardens ) just look !I have now an Alpha 900 terrific ) my best regards to all the Sony " Alfistes" Serge|
|Michael Hohner answers:|
|The Sigma and Tamron macro lenses are certainly also well worth their money.|
|#6: Comment posted by Martyn Gardner on March 13th, 2012 - 09:09:51 AM:|
|Hi, In answer to some of the information posted, try a Minolta 100mm dedicated macro lense, it is a truly awsome piece of kit that doubles as a well sized prime lense useful for portrait and general works but really comes into it's own on small works.
Being of original Minolta manufacture the quality is there and it is metal bodied.
There are good examples available but beware of fungus and bloom in cheaper items.
I think that this 3x lense is really something else and will take my photography to a new level.
Keep up the good work, regards, Mart
|Michael Hohner answers:|
|I already do own a Minolta 100/2.8 Macro.|
|#7: Comment posted by andy on June 26th, 2012 - 09:02:43 PM:|
|I have the minolta 50/2.8 and the minolta 100/2.8 and the Quantaray 90/2.8 as well as the Tamron Adapt-all 90/2.8 Macro which requires an extender to reach 1x, making it more like 180/3.5. I slobber wantonly over the 1x-3x macro, typically on Ebay, and so your review is much appreciated, although it is bound to contribute to even more cyber stalking of this lens on my part.
A little OT but are you having trouble getting clean macro shots with your SLT77? I have one also, and need to dedicate inordinate spans of time to spot removal. I feel the secondary surface has more than doubled my dust issues, even after cleaning. The mirror has a backside as well, and I don't think sony thought about where the dust would go after the sensor shook it away.
|Michael Hohner answers:|
|Dust on the mirror should not matter, because it's way out of the plane of focus. But with the sensor exposed to the outside world all the time, I also clean it more often than that of the A700.|
|#8: Comment posted by Peter on January 19th, 2013 - 03:20:34 PM:|
|Hallo Herr Hohner
Ein toller Bericht, einer selten verfügbaren Linse für den Spezialisten.
Ist es möglich das Sie das Handbuch resp. den Beipackzettel zum Download verfügbar machen könnten, falls er vorhanden ist?
Gruss aus der Schweiz
|Michael Hohner answers:|
|Leider steht da das Urheberrecht dagegen.|
|#9: Comment posted by Heiko Herrmann on August 24th, 2014 - 12:13:48 AM:|
|Die sonst übliche (und z.B. auch beim 135 STF verwendete) Bezeichnung für die Lichtstärke eines Objektives, ist Tx.x (während Fx.x wirklich nur die geometrische angibt). Seltsam, dass Minolta hier von der bei 135 STF verwendeten (und sinnvollen) abgewichen ist ;).|
|Michael Hohner answers:|
|Das ist schon korrekt so. Beim STF ist ja ein Apodisationsfilter verbaut, der tatsächlich nennenswert Licht schluckt, und damit der T-Wert stark vom f-Wert abweicht. Da ist es sinnvoll, den T-Wert anzugeben. Bei normalen Objektiven in Unendlichstellung ist der T-Wert fast identisch mit dem f-Wert, und wenn man näher fokussiert, wird die effektive Blende auch kleiner. Das 100er Makro hat z.B. bei 1:1 eine 1 1/3 Stufen kleinere effektive Blende als in Unendlichstellung.
Das besondere am 3×-1× ist lediglich, dass es nicht bis Unendlich fokussieren kann.