Here's a brief look
at the Minolta AF 135mm F/2.8 lens. Scroll down for the main review.
Lens
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2556-600 Minolta AF 135mm F/2.8
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Box contents
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Front and rear caps, and user's manual.
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Cost
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No longer manufactured, and no replacement from Sony as of 2011. Original cost roughly $119-$309 depending on purchase
year and store.
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Build quality
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Good
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Additional information
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If you can't find a good copy of the Minolta AF 135/2.8, consider the Sony 85mm F/2.8 SAM, which is similar to this lens, although shorter in focal length, and is available brand new.
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Specifications below
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Optical configuration
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7 elements in 5 groups
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Angle of view
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18° full frame, 12° APS-C
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Aperture
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7 blades, straight
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Full frame and APS-C
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Yes, and APS-C equivalent to 202.5mm.
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Depth of field and focus scales?
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Yes.
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Minimum focus, image plane to subject
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38.25" (972mm)
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Minimum focus, end of lens barrel to subject
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33.25" (845mm) with hood in stored position
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Hard stop at infinity focus?
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Yes, and shows perfect focus at infinity.
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Length changes when focusing?
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No
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Focus ring turns in AF?
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Yes
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Filter size
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55mm
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Filter ring rotates?
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No
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Distance encoder?
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No
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Max magnification
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0.16x, or 1:6.25
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Min. F/stop
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F/32
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Sony teleconverter compatible?
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No
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Length changes when zooming?
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N/A
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Dimensions WxL (my measurements)
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2.5" x 3.26" 65mm x 83mm.
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Maximum extended length (my measurements)
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4.05" (103mm) hood extended only, lens does not extend.
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Weight bare (my scale)
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12.9oz (366g)
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Requisite product shots.

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Box and lens |

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Side shot with hood in up position |

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Front element |

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Backside mount. |
The Sony A580
and Sony A900 were used for this review. For a better understanding of terms and methods used in this review, go here. The Minolta AF 135mm F/2.8 is a compact lens, with
a nice build quality and cool built-in hood. It has a gloss black finish with ribbed rubber inserts around
most of the circumference. Also included is a focus distance window with ft and m
in those colors along with DOF hash marks at F/16 and F/32. It has an infra-red focus index mark,
the red dot at F/16 on the aperture scale. The lens is made in Japan. This lens has a medium focus throw, and
it focuses a little behind the subject using the A900, I dialed in -11 for the micro adjustment, your focusing may be different.
There's a little bit of slop on the focus ring if you wiggle it by hand when engaged, and none in actual
MF use. Manually, the ring is somewhat tough to manipulate with a finger and thumb, especially
with the hood all the way retracted. Just over a third of a turn gets you from close focus to infinity. The
focus ring turns in auto-focus mode, but thankfully, not the filter ring. The aperture shape is a nice heptagon from F/2.8-8, and flattens on one side noticeably as you
stop down to F/32. This lens has
the typical multi-coatings from the 1980s, which is a somewhat green/bluish/purple
cast, and as a result, you'll see a lot of colored blobs and/or arcs depending on angle and aperture.
The sun doesn't have to be in the image to make a mess of things, so be sure and block any intense light sources
which can wreak havoc with your pictures. The small, built-in hood doesn't do much good, use your
hand for keeping the sun out of the shot if possible. In the box is the lens, caps, and owner's manual
with a warranty card, no case or pouch.
Lens flare/ghosting. Below average control.
Don't frame your shot with the sun close by or you'll be sorry. See samples below.
Color fringing (CA). Below average control, but typical for a 1980s and 1990s
telephoto lens. I see the typical fast lens, wide-open axial color fringing at F/2.8, but diminishes greatly by F/4.
There is lateral color fringing also, but it's controlled fairly well.
Bokeh. A little distracting due to a colored ring around the highlights caused by spherochromatism, see the bokeh samples
below. The aperture shape starts to show up between F/4-5.6. Color. Same as other
Sony and Minolta lenses.
Close up filter. +4 tested, which allows you to get much closer, about 8"
or 203mm to subject from end of lens.
Coma. None.
Regular filters cause no additional
light fall-off problems. Filter size is 55mm. Sony lenses that use 55mm filters are; 100mm macro, 50mm macro,
50mm F/1.4, 35mm F/1.4 G, 18-70mm, 18-55mm, 55-200mm, 35mm F/1.8, and the 75-300mm.
Distortion. Very
straight on APS-C and full frame. Check out the cropped samples below.
Distortion example
directly below.

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No distortion. |
Bokeh crops next.
Bokeh, or background highlight blur is generally good, although
I see a slight ring around the highlights at all apertures. I see some spherochromatism, meaning green tinged out of
focus highlights in the background, and magenta tinged in the foreground. This isn't something to worry about.
Crops above were taken from the center of the image, focused about 25' (7.6m), with the background about 45' (13.7m) away.
Light fall-off.
When using an APS-C camera, there is no real light fall-off
to worry about. At close focus, the light fall-off is slightly stronger.
Focusing accuracy is crucial at F/2.8!

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Focused slightly behind the subject |

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Focused slightly in front of the subject |

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Focused correctly |
Accurate focusing is crucial for telephoto lenses at wide apertures, such as the 135mm F/2.8 here.
In the top crop, the camera focused slightly behind the house, you can see this by looking at the background foliage above
the house, it's sharper than the other two crops. The middle crop was focused slightly in front of the
subject, although this shots appears better because of the lack of magenta color fringing, it's really not quite as sharp
as it could be. The bottom crop is focused correctly on the house, you can see the foliage out front and
the metal window guard on the left is sharper here. The range of perfect focus is
super slim, and the differences in focusing accuracy in these crops highlights the limits of the camera's
AF system. I used the Sony A580 for this test, but even using the A900 with micro adjustments enabled still
isn't perfect all the time. The camera's AF system chose the focus for the above crops, each time slightly
different. The best way to see if you have your subject in perfect focus is to use live view,
focus check and magnified to the max. At smaller apertures, focusing isn't so critical, that's
why cheap cameras come bundled (kit) with slow lenses, it's not just the lower cost, it's because the AF system
doesn't have to be very good to produce sharp shots. This lens focused correctly when set
to the infinity hard-stop, but if you're at shorter distances, you'll want to do a focus check to be
sure of getting the sharpest shots. The above 100% crops were taken almost 200 yards (200m) away
from the camera, so infinity for this lens at F/2.8 is somewhere beyond that distance.
Mini comp with Sony 70-400mm.
Minolta AF 135mm, @ F/5.6
Center
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Sony 70-400mm @ 400mm, F/5.6
Center
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Mid-section
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Mid-section
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Corner
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Corner
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This comp shows the differences between the Minolta AF 135mm
F/2.8, and Sony 70-400mm F/4-5.6. All crops were taken at F/5.6. The crops show my boring stamp test chart from a lens to chart distance of about
17' or 5.2m. The Sony shows a little more contrast in the centers, and a little more
resolution at the mid-sections and corners. The Minolta holds up well considering it's over two decades old, and costs
about one fifth the price of the new Sony 70-400mm. Let's check out the macro capabilities
of this lens.
Below, check out the cropped image
(300kb) of the stamp. The sample shot was taken with the Sony A 580 16.2MP camera.
The subject is a standard US stamp, 0.87"x 1.0" or 22mm x 25mm. Also, note the macro shot was taken as
close to the subject as focusing allowed; in this case a somewhat long 33.25" (845mm), measured from the front of the
lens barrel to the subject. This lens has a reproduction size of 0.16x (1:6.25) which is one-sixth life size, that's
not all that close in today's world. Fortunately, the Minolta 135mm 2.8 produced a sharp close-focus shot. F/4-5.6
were the sharpest at close focus. F/2.8 produced a pretty sharp image, but axial color fringing and veiling haze were
present. As a side note; the "1996" on the bottom left of the stamp measures a mere 1mm wide.

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As close as you can get, F/4. Click for full image. |
Full frame section next. ______________________________________________________
Full frame results using the Sony A900 below. Check out the differences when using
a film or full frame camera below. I'm only pointing out the noticeable issues as compared to the APS-C bodies, so if
I don't show it here, the results are not significantly different enough to warrant posting an additional set of images in
this section. Light fall-off
Light fall-off is definitely stronger with full frame coverage.
I see moderate levels at F/2.8, however, by closing the aperture one stop, the dark corners begin to clear up nicely.
Full image below illustrating light fall-off from A900.
This full scene shows actual-use light fall-off. It's
really not noticeable in my opinion. This bright daylight landscape scene would normally be shot around F/5.6, and light
fall-off would begone. Data for the image is; F/2.8, 1250sec, +0.30eV, ISO 200. Ghosting.
F/5.6, sun out of shot
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F/5.6, sun out of shot
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Ghosting control is awful when the sun is near, or inside the image. Contrast has been wiped out.
Word to the wise; don't wave this lens around near the sun or any other bright light. The hood does no good in sunlight.
Color fringing.
Axial color fringing is strong at F/2.8,
but stopping down the aperture helps tremendously. The crops are from the center of the image, displayed at 100%.
Center
sharpness.
Below are crops from the image
centers.
Center sharpness looks very good in a real scene, although
many shots showed an abundance of color fringing, (mostly red) and veiling haze, especially test charts. If you look
closely, you can see F/5.6-8 is slightly sharper in the foreground leaves. Diffraction causes heavy softening at apertures
smaller than F/10. Distance to subject is about 400-500' or 120-150m.
Crops from the mid-sections.
There is some softness in the mid-sections at F/2.8-5.6, with
a noticeable improvement at F/8, at which point the mid-sections are almost as sharp as the centers. Corners.
F/2.8
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F/4
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F/5.6
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F/8
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F/5.6 from mid section
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F/5.6 from center
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The full frame corners are a little soft and dark at F/2.8,
but sharpen up nicely at F/8. I see the corners look almost sharper than the mid-sections, that's a little unusual,
and makes the lens better suited for a full frame camera as there is no penalty for using the lens' full image circle. Distortion next

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Flat on A900 |
I see almost no distortion with full frame coverage, again,
this is a bit unusual, as there is no distortion using an APS-C camera. No penalty for full frame here either!
Conclusion. The relatively small and light-weight Minolta
AF 135mm F/2.8 turned in a very good performance for a twenty-plus year old lens. Getting a good
copy for under $300 would be a steal, and a nice addition to a prime lovers bag of goodies. On an APS-C
camera, this lens is similar to a 200mm F/2.8 lens for full frame. Earning high marks are:
distortion control; it's flat on full frame and APS-C; center sharpness, where F/2.8 shows a surprising
amount of detail, (although there is some veiling haze and color fringing), and light fall-off: very
little on full frame at F/2.8. The Minolta AF 135/2.8 is a small lens that can be stored in your coat
pocket if you like hand-held low light shooting but aren't sure you need that much focal length. If you want something
even smaller, check out the Sony 85mm F/2.8 SAM, obviously it doesn't have quite the reach of 135mm, but you can get them new, and it performs a little better all the way
around.
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