Equipment & Software Reviews
Classic Minolta 28-135mm meets NEX 5n
Almost all of the old lenses have something to offer modern users, I could wax lyrical for hours about the joys of the 28-85 or the 50mm Macro, and so on but the 28-135 mm is something really unique.
But before you get too excited and dive for eBay and your credit card lets first establish what this rather large jewel is not.
It isn't cheap, it isn't light and it definitely isn't a close focusing optic, about 2 metres being as close as one will get unless you are at the 28mm end of the range, where it slips into macro mode.
As an aside you can get it to focus pretty close at all focal lengths on the NEX by adding a 10 mm extension tube behind the Lens adapter, this can be useful for close range portraits, (i.e. head filling the frame) in the 100- 135 mm for example.
This is not a walk around lens, some people may delude themselves that it is, yeah sure, and a Canon 70-200 f2.8 L series is also a walk around lens. A Sigma 30mm f2.8 on a NEX is a walk around combo, the 28-135mm is a lug around combo.
What does the 28-135mm offer then.
Let's sum it up as this.
At 28mm it's sharper than the 30mm f2.8 Sigma, (but there is a trick you need to know about) at 40mm it's about perfect, at 55mm and f5.6 it is virtually line ball with the venerable 55mm micro nikkor. Between 70-90mm it is very very sharp and gives almost nothing away to a good mid range portrait lens, so long as you don't crave apertures wider than f4.
The 100-135mm range is also very good and in my tests is pretty much equal to say an Olympus 100 mm f2.8 on the NEX and probably as good as say a 135mm Nikkor f2.8.
None of the other Minolta AFs come close in "across the range" performance, but there are a few things you should know about the 28-135’ performance first.
Like most older lenses it can display chromatic aberration, it's not high by any means and better than most but it's there, on the positive side, what is there is easily fixed in post production, and when you do, the sharpness losses are minimal. The CA at the long end is pretty much invisible but it gets more obvious as the focal length is reduced. It never however gets even moderately bad and at around the 30mm setting I would say it is about equal to the Sigma 30mm f2.8 and few people complain about CA with that “little wonder”.
CA is an area where it deviates significantly from the older 28-85mm, which loses quite a bit of clarity when you fully correct the CA, especially right out in the corners.
I must point out however that the 28-85mm is a pretty amazing lens at 28mm for wide angle use if you are just using the green channel or green and a little red channel for monochrome conversions. In this mode it has a centre performance with higher resolution than the Sigma 30mm and it definitely has a special look that is worth the price of entry.....hell the 28-85 can be bought for virtually nothing, so whats to lose?
Flare is a potential issue on the 28-135mm, and by that I mean, don't even think of shooting without a really good hood and definitely don't try shooting into bright lights unless you want to start your very own flare fest. Note too, it’s not the nice sort of flare that can be used creatively, but rather a repeated pattern of flare spots.
Shooting with the light source just out of the frame will also cause significant veiling flare as that big front element catches the angled light and funnels it down through the multiple chunks of glass sitting behind it. Minolta never provided a matching hood for this lens, but you have lots of flexibility when using it on APSC formats, so a good collapsible rubber hood would be a fine choice, the ring size is a sensible 72mm.
In my instance I have made a modified “Cokin style” hood that though large, works an absolute treat, copy me if you like, I promise unless I shoot right into the light I don’t need to give flare a second thought with this little baby.
Focusing is a little different, you see it is an internal focus lens and the focus ring is actually at the back of the lens, which works pretty neatly for NEX applications as once you add the lens to the required adapter it puts the focus ring at your index finger tip without having to remove your fingers from the cameras hand grip.
I have added a little removable lever to my focus ring and this helps fine tune focus very precisely when at the tele end of things, and trust me the focus is very very touchy at the tele end. Additionally I have added a rubber band that covers the gap between the focus ring and the body but gives just a little slip. This ring means that when I am trying to obtain critical focus at the tele end focus holds better and it is just a little easy to critically nail, normally the lack of friction in the focus control can make it a bit too easy to over correct on the focus.
Generally the lens does not display much in the way of field curvature when NEX ed (cropped to APSC) and there is no noticeable focus shift as you stop down.
All three colour channels focus sharply, which might sound like an odd thing to say but in fact many older lenses and a lot of newer ones focus variably across the three channels. To give an example, the 28-85 Minolta which is a slightly older sister lens to the 28-135 focuses the green channel very sharply, particularly the central core which is about as sharp as one could possibly expect of any lens. The red channel is slightly less sharp, especially towards the outside edge of the image and the blue channel is quiet soft overall......actually the blue channel is utter rubbish! This gives images a certain look, a sort of glow which suits portraits beautifully but it's not great for when you really want clinical clarity in full colour images.
In pretty much most situations the 28-135 can be shot wide open, and really only needs stopping down a stop or less to reach peak clarity, once you exceed f8 you don't get any improvement in clarity and I feel I can see a definite drop off at f11 throughout the focal length range.
As mentioned weight is an issue and this is not a well balanced lens on the NEX 5n. (if you try to hold the body of the camera, but this is not how I use the lens).
I attach the LA-EA1 lens adapter to a focus rail which in turn is attached to an alloy handgrip, I adjust the rail forward and aft until the whole rig is perfectly balanced at the chosen focal length. This of course makes the whole setup heavier but the perfect balance makes hand held shooting very stable and overcomes much of the loss incurred by not having OSS available. I can shoot quite reliably down to 1/15 sec set up like this, especially working in the wider end of the focal length range.
Now for that little secret I mentioned earlier, the 28-135 and its sister the 28-85 both have their macro option set at the wide angle end of the range. There is a little sliding switch you move that allows you to then turn the focal length ring into the macro range.
Long ago I noticed something really odd happens when you do this on the Minolta 28-85. In this case the field curvature goes away (the 28-85 is almost a variable field curvature lens that can be dialed in via very small focal length variations) and the lens becomes close to flat field. Even more odd if you put the focus setting to the hard infinity stop and then go just ever so slightly into macro, the sharpness of the image improves markedly beyond the normal 28mm setting. In other words you use the macro zoom ring to focus for normal scenes.
Well the 28-135 doesn't change field curvature but it does get quite a lot sharper, in fact I swear that used in this way it is the sharpest lens I have ever used at that focal length and easily better in my opinion than the charming little 30mm Sigma. My general strategy is to go just into macro mode with the aperture set to f6.3, twist the zoom ring until everything just pops in the 14.8 magnified view and shoot. You do seem to lose a mm or so of focal length so its probably more like 29-30mm than 28mm but who cares. To make this easier I have actually etched a focus mark into the zoom ring so I can virtually set and forget.
Being an old school optic, the 28-135mm is low on contrast so images don't appear to have perhaps the immediate punch we see with modern glass, this is not a deficit to my mind but a bonus. When you look at how many elements there are in the lens it's no wonder its low on contrast, its one optically complex little baby and lets not forget its really a bit of an antique in the zoom world.
Lower contrast lenses tend to hold back the highlight and shadow tones a bit....kind of like the shoulder and toe effect we used to get with film. I look at it this way, it's easy to boost contrast and colour saturation but its far harder to reduce it if the file starts out being too hot. Given a choice I always prefer to work with lenses of slightly lower contrast, but before you get all “but Brad that’s just stupid” and start flaming me on a forum somewhere, remember I shoot RAW almost exclusively and cooked “Fuji Style” OOC looks don’t float my boat. Lets just say that Ken Rockwell and a lot of other photo web bloggers are diametrically opposed on this matter....my choice.
Certainly on the NEXs cropped APSC sensor there is no question about images being sharp right out to the corners at any focal length, compared to the std NEX 18-55 zoom the 28-135 is a revelation in the 35-55mm range where the kit zoom just gets progressively worse.
Colour is quite different to the kit lens, it has a warmth that is wonderfully pleasant, the kit lens is virtually neutral of course, like most modern lenses. This warmth is a characteristic of all the old Minolta AF glass, it is quite deliberate. Minolta designed all its early AF glass to have a consistent colour signature. It may not seem important today, but in the past when pro or serious photographers were shooting slide film, consistent colour with lens changes was a great bonus, remember there were no intermediate steps in which the colour could be fine tuned. In the old transparency days other than testing the film and then using CC filters to correct for each individual lens, photographers just had to put up with colour variances across images taken with different lenses.....unless you shot Minolta.
Minolta chose to go warm on the colour balance and I find the look lovely, it's a bit hard to describe, you just need to shoot some files and see it for yourself. Just a little aside here, many folk will claim that with digital you could get the same look via editing, in theory that sounds correct but in reality I have found that the subtle differences cannot be fully emulated or are very very difficult to duplicate. It is all part of the way a lens draws an image and trust me old AF Minolta glass draws in a certain way.
If you're really after a std lens colour look, you will need to fine tune the WB settings a bit, adding a little blue/cyan....or you can deal with it in post.........or just embrace it!
One practical point worth knowing is that should you tilt the lens down the weight of the front elements will cause the focal length to creep towards the tele end. The fix is easy though inelegant, stick a big wide rubber band across the junction between the zoom ring and the lens body. You can still zoom with a bit more pressure but otherwise it all stays put. Trust me you don't want creep because this is not a parafocal lens, as you zoom the focus shifts, a lot, which is again a difference between the 28-135 and its sister 28-85mm which remains in perfect focus throughout its entire range.
Currently I am devising a custom built lens handle with a remote release so I can trigger the shutter by squeezing the grip handle, I expect this to lower my usable shutter speed by another stop or so, but generally I have little problem getting fully sharp images at the 1/30 sec mark at say 60mm. I should point out that I am pretty practiced at this so for most folk 1/60 is probably more realistic.
Ultimately the proof is in the pudding. As I said I don't shoot jpegs, and frankly if you do on the NEX 5n or any other NEX variant this lens is likely not for you. Lets just say that there is a world of difference between what you can do with NEX raw and jpeg files, Sony just don’t know how to really nail in camera JPEGs, their processing does some pretty weird stuff to the lens clarity, seeming to magnify any resolution deficits, making average lenses perhaps look a lot more average than they really are. I suspect it is something to do with micro contrast....the jpeg engine just kills it, so unless the lens has very strong broad are contrast the images just look soft. This might explain why most folk rave about Zeiss glass on the NEX, which is really very punch in broad area contrast.
This is a lens for those who like it RAW. It's also a lens for those who are prepared to pay attention to keeping things really steady and taking the time to micro nail the focus in 14.8x magnified view. Remember the 28-135mm is “auto focus” ONLY if you use it with the dearer LA-EA2, which has an auto focus drive motor with the blade drive peg built in.
The NEX body does not have a focus drive motor built into it, thus the only older AF lenses that actually do “AF” in combo with the LA-EA1 are those late models with integrated focus motors.
Note also that because of the way the LA-EA1 adapter works you will not see the effect of the depth of field prior to exposure as you do with the standard kit lens, or indeed most other legacy optics when used with adapters.
If you do wish to use the 28-135 in stopped down mode to pre check DOF you will need to purchase one of the cheap adapters with a aperture lever on the lens adapter body. The downside of this route is you won't have any exif data recorded. Swings and roundabouts unfortunately, I will probably go down this route myself as seeing DOF pre-shot is very important to me and I can live without the EXIF data. All that really matters to me is “how does the shot look”!
If you are a methodical photographer who is prepared to work within the lenses limitations then this lens will reward in spades, the files are just beautiful to work with and the final edited look is superb. If on the other hand your approach to photography is more “Rockwell” like where editing is seen as an unnecessary evil then don’t buy the 28-135mm, you will be disappointed. Thats not a dig a Ken by the way, I appreciate lots of people don’t want to edit and like it punchy straight from the camera, I am just trying to make things as honestly clear as I can.
Buying a 28-135 is perhaps the real challenge, they are not that common and a good proportion of them have seen better days, and being very complex they don't like being dropped. Don't even think about one with a dented filter ring.
My advice wait until a gem comes along and pay a fair price, I figure about 400- $600.00. That's might sound a bit steep for an old school lens, but allow me to let you in on a dirty little secret, I have tested the 28-135mm against the Zeiss 24-70 f2.8 and the 28-135mm totally creamed the Zeiss, (unless you need 24mm of course or really must shoot at f2.8) and you won't buy a 24-70 f 2.8 any time soon for 400-$600.00! And that folks is meant to be a compliment also as the 24-70 is a fine lens, so don’t go stoking up the fires to burn me at the stake.
Bristlecone pine at Bryce Canyon - 75mm
Monument Valley USA - 28mm
Arizona - 100mm
Side view of "the Beast Rig" including hood, focus rail, grip and LCD viewfinder
"Beast Rig" from above