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05-16-2009, 06:40 AM   #16
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Sigma 70 macro is by far the best lens I've ever used (despite the fact that it isn't an overly expensive lens) and instantly became my favourite lens. It's application as a macro is excellent, and it's other uses (portrait, etc.) are simply stellar.

The only downside is that it is a bit heavy for full day use, but the quality of the images outway this minor fact by a total landslide.

I find I use it equally as a people shooter/portrait as my 77 ltd, which is excellent in it's own right.

Can't go wrong with the Sigma 70 - that's for sure.

c[_]

05-21-2009, 06:59 PM   #17
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I keep coming back to this image, it is outstanding. It is so smooth and detailed and evenly-lit, it looks like a computer rendering. The lack of CA is really key point of this lens.


QuoteOriginally posted by larryinlc Quote
or actually, a close-up and not a true macro shot. As some of you know, I love to photograph watches. With all the angles and shiny parts, it's a challenge. I had the chance to use my new Sigma 70mm macro and I will say this....it's terrific!! Perfect working distance, razor sharp, and a joy to handle. I think this will be my macro lens benchmark from this day forward. It's that good and it'll be hard to beat. Sharp at nearly all apetures too.



Larry
06-07-2009, 06:29 AM   #18
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Bump

I've recently had a my first burst of LBA -- supplementing my kit lens with a DA40 and now a Sigma 10-20.

I've starting thinking that my next lens should be a 70mm prime: but which one? Judging by these pix and comments, the Sigma wins out over the DA70!
06-11-2009, 06:06 AM   #19
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Beautiful image. I also have this lens and I love it.


07-06-2009, 03:08 AM   #20
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QuoteOriginally posted by larryinlc Quote
or actually, a close-up and not a true macro shot.
Awesome image! So clean and crisp.
No critique, but I could imagine this shot to benefit from a less sterile background. Perhaps a classy old brownish cloth. Probably not what you wanted but I see that beautiful image in my head and thought I'd share.
07-06-2009, 05:27 AM   #21
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Guys, look at review here. They claim that sigma 70mm has bigger magnification ratio than 1:1.


They say: "Finally, at the close-focusing distance of 10 inches, the maximum magnification ratio came in at 1:0.91 -- significantly greater than Sigma's 1:1 claim."


Sigma Sigma 70mm f/2.8 EX DG Macro AF - Lens Review from Experts at Popular Photography- Photo Tips



Its just so good that i cant wait to go shooting with it
07-06-2009, 06:11 AM   #22
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The watch photo is superb!
07-06-2009, 07:10 AM   #23
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QuoteOriginally posted by Marc Sabatella Quote
I guess that depends on what aspect you find difficult. The Raynox gives you very little control over working distance period. Maximum focus distance is fixed at something around 6 inches or so (I forget the specifics; longer for the 150 than the 250). Minimum focus distance is determined by the lens' own focusing characteristics, but in general, its not that much closer than the maximum......

So, prime + Raynox = fixed working distance, fixed magnification. Zoom + Raynox = fixed working distance, variable magnification. Whereas a true macro prime gives you a range of working distances, with magnification directly (well, inversely) related to working distance. Only a macro zoom would allow you control working distance and magnification independently.
I want to expand quantitatively on Marc's important comments. The following applies to thin-lens optics.

In the situation where a close-up lens is attached to a camera lens focused at infinity:

Working_distance_mm = 1000/diopter_strength

The focal length of the camera's lens doesn't matter.

For example, a Raynox DCR 150 (4.8 diopter) close-up lens gives a working distance of 1000/4.8 = 208mm = 8.2". So if 200mm (8") is a good working distance for your purpose, choose a roughly 5 diopter close-up lens. If you need 400mm (16") you'll want a 2.5 diopter close-up lens, etc.

The focal length of the camera's lens in combination with the close-up lens determines the magnification.

Magnification=Focal_length/Working_distance

So, continuing the Raynox 150 example, a 200mm lens yields about a 1:1 magnification, while a 50mm lens yields a 1:4 magnification. A nice magnification range I think, with a reasonable working distance. A 100mm macro lens at 1:1 would have a 200mm working distance for comparison.

Compare this with a Raynox DCR 250 (8 diopter) close-up attachment which has a working distance of 125mm (5.12"); closer, however a shorter camera lens is required for magnification.

It looks to me like a Canon 250D or Raynox DCR 150 (or any other good achromat in the 4-5 diopter range) would work well in combination with a long zoom lens for hand-held macro work.

Dave

Disclaimer; the above is approximate & neglects things like the actual location of a complex lens' principal plane, lens hoods, lens recess, etc. Still, I believe it is reasonable guidance for choosing close-up supplemental lenses for macro work.

In real life, the working distances estimated above are maximums, and the magnifications are minimums. For maximum magnification estimates, the lens' effective extension while focusing must be taken into account (but the effect isn't large for normal lenses.)


Last edited by newarts; 07-06-2009 at 07:32 AM.
07-06-2009, 03:43 PM   #24
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QuoteOriginally posted by newarts Quote
I want to expand quantitatively on Marc's important comments.
Thanks a lot, Dave.

I think you should submit this as an "article" to the knowledge base. Add some calculations for extension tubes, if you like, but I think it is a nice reference already.
07-06-2009, 07:13 PM   #25
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Here's another photo taken with the 70mm from a little while back. For me, this is the perfect lens for watch movements. I should also mention that these photos are not intended to be art. As a member of the NAWCC, I shoot these old movements for identification purposes. I do like to make them look nice though and all those shiney parts, angles and engraving make it a real challenge.



Larry

Last edited by larryinlc; 07-06-2009 at 07:20 PM.
07-06-2009, 07:50 PM   #26
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QuoteOriginally posted by larryinlc Quote
Here's another photo taken with the 70mm from a little while back.
That's like a 3D scan. Only better.

QuoteOriginally posted by larryinlc Quote
I should also mention that these photos are not intended to be art.
You fail.

Great job with the lighting and, if that's possible, you made me want the lens even more badly.
07-06-2009, 07:55 PM   #27
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QuoteOriginally posted by larryinlc Quote
Here's another photo taken with the 70mm from a little while back. For me, this is the perfect lens for watch movements. I should also mention that these photos are not intended to be art. As a member of the NAWCC, I shoot these old movements for identification purposes. I do like to make them look nice though and all those shiney parts, angles and engraving make it a real challenge.



Larry

Larry, the detail and luster of the metal is wonderful, nice capture.



.
04-19-2010, 11:16 AM   #28
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I just ordered one on Ebay for $350, with tax and shipping the total came to $400. Cheapest price I've found in Canada is at henry's for $649 + Tax. So I'm quite happy with it. Now just have to wait for the shipment ...

Will post some shots when I get it. First investment after purchasing the ist DL about 4 years ago and learning photography with the kit 18-55 lens. So I'm excited...
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