Differences between DC and EX lenses?

Can someone please explain the difference?

I've only used one Sigma lense which came with the second-hand camera and it is an EX lense.

http://www.sigma-imaging-uk.com/lenses/lens-tech.htm
DC Lenses

"These are special lenses designed so that the image circle matches the smaller size of the image sensor of most digital SLR cameras. Their specialized design gives these lenses the ideal properties for digital cameras, the compact and lightweight construction is an added bonus!"

EX Lenses

"The exterior of this lens is EX-finished to denote the superior build and optical quality, and to enhance its appearance."

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Thanks Thomas!

No - I think you have got that wrong. The DC lenses are designed to cover the smaller sensor (whereas the EX cover 35mm) and are not inferior - just worth remembering that they are more compact and lighter because of their stated coverage.

One would opt for the EX if there was any chance of ever using on, say, a 35mm film SA7 or, of course, if a full-frame Foveon sensor appears at any time. The DC lenses are a later addition to the range - virtually applies to all manufacturers - and are cheaper, smaller and lighter without being optically inferior.

However, many would opt for the EX because one would only be using the central part of the projected image circle.
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Zone8

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Zone8 said:

No - I think you have got that wrong. The DC lenses are designed
to cover the smaller sensor (whereas the EX cover 35mm) and are not
inferior - just worth remembering that they are more compact and
lighter because of their stated coverage.

Click to expand...

Well, you got that wrong too.

There are EX DC lenses : http://www.sigma-photo.com/lenses/lenses_all_details.asp?navigator=6

DC is for the camera format, EX is for the build quality.

Zone8 said:

The DC lenses are a later addition to the
range

Click to expand...

Short answer: yes, EX lenses are better.

I have the 18-50mmDC which is different from and not as good as 18-50mm EX. So think of EX as build quality. By the way, the 18-50mmDC physically attaches of course to the SA mount on my film 35mm Sigma SA7, but shows a black interior of the lens at most settings, thus isn't realistically usable on the fullsize 35mm film camera. So DC lenses are for "digital" in the sense they're not for fullsize 35mm film equivalent. Watch for the "DG" designations too, which refer special coatings optimized for digital DSLR use. sharpvision: The Sigma website, lenses section is the absolute best source for understanding specs, looking at diagrams of interior construction, showing you the differences. Learn much more about the DC, EX, DG designations before you buy!
Best regards, Sandy
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http://www.pbase.com/sandyfleischman

DC - covers only the smaller APSC-sensor
non DC - covers full format

EX - high grade optics from SIGMA
non EX - consumer grade/budget optics

Examples for EX and DC lenses:
10-20mm f4-5.6 EX DC HSM
18-50mm f2.8 EX DC
18-50mm f2.8 EX DC Macro
30mm f1.4 EX DC HSM
50-150 f2.8 EX DC HSM

Examples for DC lenses without EX finishing/quality:
17-70mm f2.8-4.5 DC Macro
18-125mm f3.5-5.6 DC
18-200mm f3.5-6.3 DC
18-200mm f3.5-6.3 DC OS
55-200mm f4-5.6 DC

Generally said:

• if you go for ultimate quality buy a prime lens
• EX optics will have better specification than non EX
• A zoom lens will have better quality the smaller the zoom range (2x is better than 10x)
• DC lenses will give you more distortions but considerably less weight than non DC lenses
• DC lenses are more affordable for comparable quality
• DC lenses are not suitable on Sigma FF cameras (analog Sigma cameras)

Some very affordable non EX optics with better than average quality according
to the opinions others:

• 17-70mm f2.8-4.5 DC Macro (near EX performance, gread walk around optics)
• 55-200mm f4-5.6 DC (best stopped down to f8.f11)
• 70-300mm f4-5.6 DG APO Macro (macro 1:2 for insects, avoid the non macro version)

regards

wolfgang

DC-digital compact- for sensors of 1.5 and up
DG digital with highest resolution-covers 24x36mm
OS-OPTIC STABILYZER
HSM hyper sonic motor autofocus
ASP aspherical
there are these combinations:

DC

EX DC(10-20 HSM, 30/1.4 hsm among others

APO EX DC HSM (50-150)

DG

EX DG(8 circ fisheye,15 diag. fisheye, 70-300, among others also with macro)

APO DG(70-300 MACRO among others

APO EX DG
(150macro/180macro/300/500/800/ 50-500/70-200/70-300/80-400(OS)
APO EX DG HSM(100-300/4 120-300/2.8 300-800/5.6 300/2.8 500/4.5 800/5.6

EX DG ASPHERICAL(12-24 / 12-24 hsm,15-30(non-macro?) 17-35/20/24macro/28macro
15-30 macro

EX fisheye-circular
EX fisheye-diagonal
EX asp hsm-14/2.8 only in pricelist-not in prospectus 2006.09 anymore

it would be nice to have a complete list, not listed like in official prospectus but like the above one.

there is a second tiger shot made with 300-800(without info about focallenght) shown at photokina. i didnt show that because i found the 150-macro-shot of g.borgemeister sharper.

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This one should easily go to 150 posts also....
Boris
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