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06-18-2007, 06:23 AM   #1
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Question about Macro

Ok, I wasn't getting any answers in my previous thread so I'll start this new one and see if anyone can help. I recently purchased a Sigma 70-210mm f4-5.6 lens to use with my K100D. The lens has been good in the test shots I have used it for so far, but on thing I was wondering is about the macro function. I have been kind of disappointed with the range of focus i.e. I can't stand as close to subjects as I want sometimes, and the focal length will not allow me to fill the frame with the subject. Can this be achieved with some kind of adapter, or should I start looking for another lens?

06-18-2007, 06:59 AM   #2
roy
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this is not a macro lens even tho it says so. probably highest mag. is 1:3-5. you can put diopters on it or extension tubes on it to get to 1:1 but why bother. it's not even close to being a macro lens. IQ will suffer if you do. best and cheapest way to go is get a 50mm f2 and a set of ETs..
06-18-2007, 10:20 AM   #3
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I think that is probably the Sigma lens that I used to have before I bought the 70-300. If I remember correctly it has a 52mm thread and there is a matched 'achromatic macro lens-AML) for it but it's been out of production for a while. I don't think it gets you to 1:1 but it is a cheap option if yu can find one. I have one and it's a two element lens that's roughly equivalent to a +2 dioptre. As roy says there is a reduction in quality but not as much with this one as the cheap ones that are sold on ebay. You could do worse than buy the cosina 100mm f3.5 macro lens which is dirt cheap and quite good quality. It was sold under a lot of different names like phoenix and vivitar and Pentax (though theirs has the smc coating). It is a 1:2 lens that if you are lucky comes with a matched adapter to give 1:1. I've used one for a while and there is a german on Ebay who is selling them for about 60. To see some photos taken with one do a search in flickr groups for cosina 100 macro. There is a group dedicated to the lens and there are many good photos on there.

Carl
06-18-2007, 04:26 PM   #4
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It actually has a 55mm thread, so I don't think it's the same as you had bottesini. Thanks for the info though. I'll probably just have to save my pennies to get a better lens for macro. Do I want to look for a 1:1? I don't have the lens with me now, but I think it's something like 1:4.2. What does this ratio mean anyhow?

06-18-2007, 04:58 PM   #5
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1:1 = real life reproduction
1:2 = 1/2 size
and so on.

If you don't need 1:1 macro and is on a budget, look for Pentax/Cosina/Promaster 100mm/f3.5 or Tamron/Sigma 70-300mm.

For 1:1 macro, choose one from the following (in increasing price order):
Sigma 105/2.8, Tamron 90/2.8, Pentax DFA 100/2.8
or
Sigma 50/2.8, Pentax DFA 50/2.8

cheers
Kenny
06-18-2007, 05:02 PM   #6
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QuoteOriginally posted by Moggman Quote
It actually has a 55mm thread, so I don't think it's the same as you had bottesini. Thanks for the info though. I'll probably just have to save my pennies to get a better lens for macro. Do I want to look for a 1:1? I don't have the lens with me now, but I think it's something like 1:4.2. What does this ratio mean anyhow?
The ratio refers to the macro magnification. So a 1:1 is life size (the image on the sensor/film is the same as the actual item being photographed). 1:4 is 1/4 life size and so on. I think from the very good info you have gotten so far, you may be well advised to look for a set of extension tubes and a 50mm f2 or better yet a f1.7. Be careful with buying a Takumar 1.4. Very tempting but the glass was treated with a radioactive element that yellowed over time. It can be cured but why bother. With those 2 pieces you could stay well under $150.00 and have a very good setup (which can be expanded as well).

The other option is the Cosinar/Vivitar/Phoenix 100mm with the diopter. I have this version and although it feels like a Fisher Price toy, it's a very good macro lens.
06-18-2007, 05:32 PM   #7
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I've got a 50mm f2 and although I've never tried using extension tubes with it I have used it for macro photography by holding it on my camera backwards. It works, although I doubt that it's 1:1 Possibly 1:2 though

There are adapter's to hold it on the camera backwards for you, and they're cheap.
06-19-2007, 04:30 AM   #8
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Little Laker knows of what he speaks Look for Reversing Rings, and they should be REALLY inexpensive. I did the "reversed 50mm" trick and you can get in REALLY close!

I now have the Sigma 105mm f/2.8 EX DG Macro and it's a great lens.

06-19-2007, 05:41 PM   #9
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you are best to get a true macro lens.

My combination is a 100mm Pentax SMC-M F4, which gives a 1/2 life scale reporduction without extension tubes.

I combine this with a 1.7x Autoficus TC which when you combine it with the digital correction factor gives better than 1:1 reproduction ratio plus autofocus over a reasonable range of focus.
06-19-2007, 07:06 PM   #10
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I have the Pentax 50mm DFA Macro. It's absolutely awesome. And it has the "quick shift AF override" which you only get on DFA lenses. I wouldn't even think about using anything other than either the 100mm or 50mm DFA Pentax macro lenses.

Plus the 50mm DFA is beautifully built, compact and lightweight, bla bla bla

I like it, OK?

What I don't like is that I'm totally hooked on the "quick shift" AF override feature which means despite the huge range of lenses (including old cheap ones), I only want Pentax DFA lenses! :-)
06-20-2007, 07:11 AM   #11
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If you use the reversing rings, do you lose control of the Aperture? my 70-210 has an aperture ring on it, so I could control it that way, but I was just wondering for reference.
06-20-2007, 08:42 AM   #12
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QuoteOriginally posted by Moggman Quote
If you use the reversing rings, do you lose control of the Aperture? my 70-210 has an aperture ring on it, so I could control it that way, but I was just wondering for reference.
If you use a long lens you negate much of the macro capability. Remember you are reversing the lens so everything is reversed. A long lens that normally zooms in to a subject will do the reverse mounted backwards. The most common lens to use is a 50mm. Partly due to weight and the wide aperture they offer.
You can still use the aperture to try and control DOF but that is somewhat limited.

I would never mount a reversing ring on a long lens that is usually heavier. You risk damaging or breaking the filter threads on the lens with so much weight so far from the reversed mount. The filter threads were designed for a lightweight filter not the entire weight of the lens.

Another good lens to try would be the F series 35-70 or 35-80. Both are fairly light and will offer some ability to vary the magnification and frame the shot.

Here's another DIY project. I offer it because maybe you can't find a reversing ring for a particular filter size or like me you're just cheap and want to try something new without spending any money before knowing if it will work. Note: he suggests breaking the glass of the filter to remove the glass. That's not required with many filters. If you look closely on many, you'll see they use a "C" clamp or split "O" ring to hold the glass in place. Use a small screwdriver and the glass comes out easily. Save those old scratched filters and you can use them as a stacked set as a hood as well.

- Sometimes these DIY things are cheap and handy and no I don't have any Duct tape on my camera and I don't use a stick with a screw as my monopod! Lol

DIY - Reverse Macro Ring | DIYPhotography.net

Last edited by Peter Zack; 06-20-2007 at 08:49 AM.
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