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04-14-2010, 10:01 PM   #1
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Thinking on a new Macro lens. Advice?

I'm thinking on picking up myself a new macro lens and would like some advice.
I'm currently taking a closer look at these:

Tamron 90mm SP AF 2.8 Di Macro

Pentax D FA 100mm 2.8 Macro

Both look good spec-wise and review-wise which of course, makes the decision harder

I'm currently using a Pentax M 50mm 1.7 on a set of tubes and getting great results from that, but I would like to be able to get great macros out in the field and then be able to catch more regular range shots without having to change lenses.
Also, in terms of the studio setup macros, is it a feasible notion to put the tubes on either of the above lenses for ridiculous magnification? And if so, how much mag could I get and how close would my subject be from the lens?
I found these lenses rated high on a few review sites but are there some others I should also look at?

Sorry for all the questions, hope I'm not confusing people

04-15-2010, 12:55 AM   #2
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What range do you think you want? I guess if you're doing a studio then I would say that you only really need 1:1 magnification, anything more than that will probably not be very useful to you. There's also the Sigma 50mm f/2.8 lens which is a bit cheaper than those if price is an issue, but I've heard great things about that Tamron.
04-15-2010, 03:10 AM   #3
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If a lens is dedicated to macro work, in studio or field, it needn't be AF. I have a great old M42 Vivitar 90/2.8 macro that works just fine. If you want to use it for other purposes also - portraits, general short-tele work, grab shots - AF is nice to have, and most modern macros in the 90-105 range are excellent.

But don't put a macro lens on tubes. LOTS of tubes are needed to gain magnification on a longer macro. My 90, fully extended for 1:1, is already out 180mm. To go to 2:1 I'd need another 90mm of tubes; for 3:1, I'm extended out to 360mm. That's pretty precarious, with a lot of weight hanging out there.

For crazy magnification, use a thread-reversal ring to stack lenses. Magnification is the ratio of the primary to the secondary. With a 105mm primary and a 35mm secondary reversed on it, magnification is 105/35 or 3:1. Put a 24mm secondary on a 135mm primary and you're over 5.6:1. The gotcha: the primary must be wide open or your image is just a little circle. The secondary needs a manual aperture ring; that's where you set f-stops, and you can't tell exactly what that f-stop means, because its no longer at its designed focal length. So just take test exposures, lots of test shots, lots of chimping. At least you're not paying for film.

Oh yeah, working distance at great magnification is VERY VERY close. Use a good tripod. Use a K20D or other cam you can tether, and fine-tune the focus in a large monitor. You'll quickly learn which lenses are suitable as secondaries.

Last edited by RioRico; 04-15-2010 at 03:15 AM.
04-15-2010, 05:02 AM   #4
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It depends what you want to do with it, on the subject side of reality, I mean. I have several macro lenses, all manuals: SMC Takumar 50/4 macro (1:2), Bellows-Takumar 100/4 (1:2, but only of use on a bellows, which seems to be disqualifying this lens for you), SMC Pentax-A 100/4, and, bought only recently, the Vivitar 55/2.8 (1:1). All lenses are very sharp, but I must say working with the Vivitar is just extraordinary. The extra magnification is great, and working with a larger aperture is often *the* question of getting or missing a shot.

I think macro work asks for manual operation. AF is hunting too often when making close ups! So, if it's only for macro, you might as well choose a (cheaper) MF lens.... And in that case, I would highly recommend the Vivitar 55/2.8!!

Much is said about a ~50 or a ~100mm macro lens, or probably even longer. I like the 50mm work, because of the OOF rendering. But for insects and other small critters, 50mm might be a little threatening, since you have to approach real close....

In case you want to see some examples made with the Viv, you could see this, or this thread.

04-15-2010, 08:02 AM   #5
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To get back to your original question, either lens you mention will work well but the Tamron offers the best bang for the buck.
04-15-2010, 11:02 AM   #6
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QuoteOriginally posted by Ouroboros Quote
I'm thinking on picking up myself a new macro lens and would like some advice.
I'm currently taking a closer look at these:

Tamron 90mm SP AF 2.8 Di Macro

Pentax D FA 100mm 2.8 Macro

Both look good spec-wise and review-wise which of course, makes the decision harder

I'm currently using a Pentax M 50mm 1.7 on a set of tubes and getting great results from that, but I would like to be able to get great macros out in the field and then be able to catch more regular range shots without having to change lenses.
Also, in terms of the studio setup macros, is it a feasible notion to put the tubes on either of the above lenses for ridiculous magnification? And if so, how much mag could I get and how close would my subject be from the lens?
I found these lenses rated high on a few review sites but are there some others I should also look at?

Sorry for all the questions, hope I'm not confusing people
I had a version of the Tamron and now have the Pentax (WR) 100mm lens. Both are great lenses but I sold the tamron a long time ago. To get 1:1 Magnification out of the Pentax, or any other macro, you're pretty much right on top of the subject. My Personal preference is for the Pentax because it's body size is about half (maybe a little more than) that of the Tamron. That said, what I would Like to have had on the Pentax, is an aperture ring. It isn't a deal breaker for me because I have both digital and film cameras that can control the auto aperture. Both being full frame lenses, if you want to shoot film, that may be a deciding factor for you.

04-15-2010, 11:02 AM   #7
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QuoteOriginally posted by RioRico Quote
If a lens is dedicated to macro work, in studio or field, it needn't be AF. I have a great old M42 Vivitar 90/2.8 macro that works just fine.
I agree 100% with this. My macro is the M 100/4, and I never miss AF using it. In fact, I much prefer catch-in-focus when chasing bugs around the yard.
QuoteQuote:
If you want to use it for other purposes also - portraits, general short-tele work, grab shots - AF is nice to have, and most modern macros in the 90-105 range are excellent.

But don't put a macro lens on tubes. LOTS of tubes are needed to gain magnification on a longer macro. My 90, fully extended for 1:1, is already out 180mm. To go to 2:1 I'd need another 90mm of tubes; for 3:1, I'm extended out to 360mm. That's pretty precarious, with a lot of weight hanging out there.

For crazy magnification, use a thread-reversal ring to stack lenses. Magnification is the ratio of the primary to the secondary. With a 105mm primary and a 35mm secondary reversed on it, magnification is 105/35 or 3:1. Put a 24mm secondary on a 135mm primary and you're over 5.6:1. The gotcha: the primary must be wide open or your image is just a little circle. The secondary needs a manual aperture ring; that's where you set f-stops, and you can't tell exactly what that f-stop means, because its no longer at its designed focal length. So just take test exposures, lots of test shots, lots of chimping. At least you're not paying for film.

Oh yeah, working distance at great magnification is VERY VERY close. Use a good tripod. Use a K20D or other cam you can tether, and fine-tune the focus in a large monitor. You'll quickly learn which lenses are suitable as secondaries.
If one uses a reversed lens, the working distance is the registration distance (lens mount to film/sensor plane) for any lens mounted on any other lens, or on the camera directly. It does not change at all, no matter the lens. If you think about what you are doing with the lens, you are substituting the subject for the film plane. And working distance is VERY, VERY close indeed! You have to pay attention to the aperture levers while working, you are so close. My favourite reversal was with an M 28/3.5 reversed on the mount rather than on another lens. It gives slightly greater than 2X magnification. Perfect for jewelry and such. Not so good for bugs. They don't like big shiny things 40 odd mm away from them.
04-15-2010, 01:54 PM   #8
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Those are both great lenses, as is the Vivitar Series I 105mm, also marketed by Kiron and Lester Dine (dental folk) in similar versions. You will find glowing reviews of all in the reviews database. I only mention it because it is what I use.

Depending on your subject you will need to carefully consider lighting. A ring flash can be a great boon as you will want apertures like f/22 for 1:1 work. Unless you are under direct sun, extra flash sure helps.

04-15-2010, 02:12 PM   #9
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Hm.... I would get the Pentax 100 WR.

It is constructed like one of those limited lens!

04-15-2010, 02:47 PM   #10
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I haven't used either the Tamron 90/2.8 or the Pentax DFA 100/2.8 WR, but I've heard great things about both of them. Bokeh with the Pentax WR is supposed to be great--there's a previous thread with examples; the rounded blades help in that regard.

That said, I just picked up a Kiron 105/2.8, and I love it. Its build quality is great, and the focus is superb. Yes, it lacks AF, but in a macro, that's okay with me. I wish it were WR, but one can't have everything.

But I don't think you could go wrong with the Tamron. It was on my short list of macros I'd hop on when the time was right. But then the Kiron showed up, and it was pretty much at the top of my list, so I went with it instead.
04-15-2010, 02:53 PM   #11
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QuoteOriginally posted by Canada_Rockies Quote
My macro is the M 100/4, and I never miss AF using it. In fact, I much prefer catch-in-focus when chasing bugs around the yard.
I haven't really tried catch-in-focus yet, but I'll be trying it soon. Hopefully it will work not only with insects and such, but with other quick-moving subjects--say, our five-year-old. . . .
QuoteOriginally posted by Canada_Rockies Quote
My favourite reversal was with an M 28/3.5 reversed on the mount rather than on another lens. It gives slightly greater than 2X magnification. Perfect for jewelry and such.
Another good tip. I love my M28/3.5, so this is yet another good thing about it. When I get a 49mm RR, I'll have to give it a try!
04-15-2010, 02:55 PM   #12
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DFA100mm f2.8 WR as a Macro..

04-15-2010, 02:59 PM   #13
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DFA 100mm f2.8 WR Macro, @f2.8



04-15-2010, 03:01 PM   #14
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DFA 100mm f2.8 as a short telephoto



04-15-2010, 03:03 PM   #15
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DFA 100mm f2.8 WR coupled to a Pentax-F 1.7x AF adapter



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