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Old May 11, 2009, 4:24 PM   #1
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Default Tamron 90mm or Pentax 100mm Macro lens

Hi All

after having my K20d for less than a week, I am thinking of getting a Macro lens. After looking around here and elsewhere on the net, these two lenses seem to get very good write ups for their macro ability, and are about the same price. My question is - is there much difference in their non-macro ability? I've seen a few pictures from both being used as a fixed length telephoto lens but no-one seems to mention anything about them apart from for macro use.

Thanks

thedoctor
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Old May 11, 2009, 10:57 PM   #2
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I don't own either one of these lenses, my macro lens is the Vivitar Series One 105mm macro lens that I think was made by Kiron, and sold under a couple of names (and I love it). It was an unsold lens that I purchased from Trader Jim on ebay (he had a bunch of them), so cheaper than either of these lenses. It's also an "A" lens - manual focus/auto exposure.

But I have taken a few comparison shots with the Pentax 100mm and mine, and didn't see much difference between the two lenses. It would be a good choice. However, I've seen such awesome pictures posted around here with the Tamron 90mm that I suspect it may be a hair better than the Pentax. But I think the differences are going to be very slight and you'd probably love either one.
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Old May 11, 2009, 11:41 PM   #3
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I find that my best lens for macro work is my old Pentax 50mm "M" f/1.7. Due to its low-light capabilities I can set an aperture of smaller size than most lens, and get a reasonable depth of field. At its best the lens face will be a little less than twelve inches from the subject. The clarity can be quite good, and sizeable enlargements can fremain very sharp.
I know that specialized lenses can get closer, but will you be getting any better results?
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Old May 12, 2009, 10:56 PM   #4
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I own the Tamron 90mm f/2.8 macro lens. It does 1:1 macro, but I have yet to use its macro features. As a fixed-focal lens in non-macro mode, it's quite nice. It's surprisingly sharp, even at f/2.8. Focusing with my K20D is nice and snappy (albeit a bit loud due to the screw). I do find the manual clutch to be a bit annoying, as it alone does not enable manual focusing; you must still switch the focus to manual on the camera before the focus ring will work.

Here's a non-macro shot:


- Jason
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Old May 13, 2009, 3:48 PM   #5
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Quote:
Originally Posted by thedoctor View Post
Hi All

after having my K20d for less than a week, I am thinking of getting a Macro lens. After looking around here and elsewhere on the net, these two lenses seem to get very good write ups for their macro ability, and are about the same price. My question is - is there much difference in their non-macro ability? I've seen a few pictures from both being used as a fixed length telephoto lens but no-one seems to mention anything about them apart from for macro use.

Thanks

thedoctor
I have both . Just uploaded a heavily cropped image taken with DL and FA100mmF2.8 . Even at F19 the DoF is still little







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Old May 13, 2009, 5:42 PM   #6
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My experience with macro lens used in Non-Macro mode is they are among the sharpest lens on the market bar none. The DOF will be thin at low f/stops and close range but as a portrait lens they are too sharp. Not soft enough in other words. But for landscapes and general shooting they are very very good. You should be happy with either one of those.
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Old May 14, 2009, 12:36 PM   #7
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Hi thedoc,

Macro lenses -- the choice is always hard since they are pretty much equal in optical quality -- but in another sense, it's easy because they are all very good, so you can hardly lose. If you plan to use the lens a lot as a "normal" telephoto/portrait lens, one feature that you might look for is a focus limiter, in an autofocus lens. Dedicated macro lenses all have an extremely wide range of focusing distances, so the focus ring rotation from nearest to infinity (lock to lock) is very long. This can be very frustrating if the AF system fails to lock the first time. The only one that has a focus limiter that I'm sure of is the Pentax FA 100 macro. Unfortunately, this lens is only available on the used market as it was superceded by the D FA 100 macro which doesn't have a limiter.

Something else to consider might be weight. I personally own a D FA 100 macro, mainly because it's easily the lightest of the 100 macros made. Handholding for macro requires a lot of light, since you need to use the smaller apertures to gain greater depth of field. This, in many cases means the use of an external flash -- which means more weight -- which makes handholding that much harder. . .

Here's a weight breakdown of the major AF alternatives in 1:1 100mm macros.

Pentax D FA 100 macro 345g (12.2 oz)
Pentax FA 100 macro 600g (21.3 oz)
Tamron SP 90 macro 405g (14.3 oz)
Sigma EX 105 macro 457g (16.1 oz)

There are, of course, a wide range of great manual focus 100 macros, some of which have already been mentioned in this thread. One thing that you might want to consider if looking at these is that some of them are 1:2 native, and require an adapter (either an extension tube or add on lens) to get to 1:1.

Good luck in your search. There are a lot of quality choices out there.

Scott

Here's a sample "portrait" of an American Kestrel with the D FA 100 macro at f2.8 showing the very thin DOF.
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Last edited by snostorm; May 14, 2009 at 2:58 PM. Reason: added text
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Old May 14, 2009, 8:22 PM   #8
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Quote:
Originally Posted by snostorm View Post
The only one that has a focus limiter that I'm sure of is the Pentax FA 100 macro. Unfortunately, this lens is only available on the used market as it was superceded by the D FA 100 macro which doesn't have a limiter.
I just want to add that Tamron SP 90 macro also has a limiter too.


Nice shot of a American Kestrel



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