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  Reviews by: Georg Dittié  

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Canon MP-E 65mm f/2.8 1-5x Macro Photo

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Review Date: Feb 17, 2008 Recommend? yes | Price paid: $1,200.00 | Rating: 10 

 
Pros: build quality, IQ, range, ring flash easy to mount
Cons:
you have to know what you are buying, a little bit heavy

This lens is my portable microscope and it is in my bag on any hike into nature. The lens ist only one of four neccessary parts to make successful macro images, a macro rail, a tripod and a ring flash are indispensable too.

Depth of field is incredible shallow like any microscope, correct focusing by hand is nearly impossible. With a tripod and a macro rail it's no matter of concern. The bulky barrel casts often shadows on the object, using a ring flash is a good idea !

Dont expect something like autofocus, chose the magnification and then move the whole lens with attached body an ring flash by the macro rail. That's the trick for wonderful results.

Image quality is superb, no color, no distortion or anything else.



 
Sigma 10-20mm F4-5.6 EX DC HSM

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Review Date: Apr 12, 2006 Recommend? no | Price paid: $450.00 | Rating: 5 

 
Pros: really ultrawide for APS-C sensor cameras amazingly low distortion
Cons:
zoom lens, a 10 mm prime would be better very bad (no ?) quality check after manufacturing plastic barrel with large tolerances

This lens makes me feel very ambivalent. It is the only ultra wide with no distortion for the Canon 10D, which cannot use EF-S lenses, but the image and particular the build quality are the worst I've ever seen from Sigma.

My copy is useless with full aperture at 10 mm. The right quarter of the image is not only soft, its defocused. The overall focus is allways to short, I have to focus it beyond the infinity mark to get usable images. I assume to large manufacturing tolerances of the plastic barrel of the lens.

The situation is less severe for 15mm and longer. With 20 mm the lens delivers nice and crisp images despite the focussing issue.

I don't expect perfect images from such an extreme retrofocus zoom lens, but I expect symmetrical images and nor a decentered and defocussed lens.

But there is a workaround: Switch the AF off. Stop the lens down at least to 8.0 Fix the focus ring with tape to the focus position which delivers the best image and use the lens as a fix focus design: The depth of field is incredible large at 10mm / 8.0 Focussing is not neccessary.

With theese settings the lens delivers an image quality which can be use up o 6*9" prints. CA ist visible, but not disturbing, same for vignetting (which is an principal issue for ultra wides !). The distortion ist amazingly low.

Since I lost the guarantee card and throw away the original box, I have no chance to return it, I have to live with the limitations.

I can't recommend this lens, to design a zoom lens in combination with an extreme retrofocus desing as an ultra wide is in my opinion still beyond our optical skills. A prime with better mechanics and a trace of quality check before delivery would be preferable.

The better alternative is to use the Sigma 15/2.8 fisheye with a defishing software afterwards. The 15/2.8 fisheye is a really decent lens and tack sharp from corner to corner, not to speak about the additional 3 stops !


 
Sigma 24-70mm f2.8 EX Aspherical DG DF

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Review Date: Dec 15, 2003 Recommend? yes | Price paid: $440.00 | Rating: 8 

 
Pros: tack sharp at f5.6 and slower, focus down to 40 cm, virtually no vignetting, very versatile, works perfectly with Canon 10D (except using the build in flash)
Cons:
soft wide open, severe astigmatism in the edges wide open, bulky, strange double MF switch, 82 mm filter thread, some flare

I expected less from a zoom like this: combining large aperture with a zoom factor 3 together with really satisfiying image quality is not an easy task. But Sigma manages it well.

The image quality stopped down to f5.6 is really amazing, from infinity to the macro distance. Despite the large number of lenses the contrast is very good. This comes together with virtually no vignetting. Only wide open the image quality is only average (and poor at the edges ...)

Its bulkiness disables the build in flash of the 10D - it throws its own shadow on the images at focal length of 40mm and shorter.

I can recommend this versatile lens to everybody who is not to lazy to carry a bulky lens around and who needs no build in flash.


 
Sigma 15mm f2.8 EX Diagonal Fisheye

15mm_Lg_1_
Review Date: Dec 15, 2003 Recommend? yes | Price paid: $425.00 | Rating: 10 

 
Pros: works perfect with Canon 10D, very sharp even wide open, smooth focussing
Cons:
very little flare, fisheye distortion has to be corrected with software.

This lens is the perfect solution for anybody who looks for a real wide angle lens for APS sized DSLRs. For theese cameras it's like a 20mm for analog ones. The image quality is really incredible, stopping down is only neccessary to reduce light. Particular at night it delivers pinpoint start from edge to edge and full contrast.

The typical fisheye distortion is no problem, it can be corrected with software or accepted, if the image contains no or very little straight lines. For star constellations the distortion is an advantage.


 
Sigma 8mm f4 EX Circular Fisheye

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Review Date: Dec 15, 2003 Recommend? yes | Price paid: $452.00 | Rating: 6 

 
Pros: real circular fisheye, the only AF on the market, works fine with the Canon 10D, build quality is ok, not too big and heavy
Cons:
blue image rim, visible decrease of sharpness and increasing color aberation with growing center distance

My opinion about this lens is ambivalent: This is the only full AF circular fisheye on the market with full stop functionality. The image circle is cropped by APS size chips, but this is not an disadvantage, the field of view is still breathtaking.
On the other hand the image quality is good only at the center and poor at the rim.
The lens suffers from severe color, the red and blue parts of the image are larger than the green part. Less important is the bluish rim itself. The sharpness decreases visibly from center to the rim.