Bigma question? DG vs non DG

Does anyone know how by looking at the lens to tell if it is the DG version of the 50-500 or the older non DG version?

Looking at the product photos on Amazon, the DG (both OS and non-OS) have DG explicitly stated on the lens where it says:

Sigma
50-500mm 1:4-6.3 APO DG HSM

or

Sigma DG
50-500mm 1:4-6.3 APO HSM

(the latter is the OS version, since it says "Optical Stabilizer" further up the lens).

I can only presume the older non-DG version doesn't say that (can't find any images with my Google-Fu today).

shinksma

So if it is DG it will definately say DG on the lens?

What are the differences between DG and non DG? not talking about the OS version.

bentlax33 wrote in post #12903941
So if it is DG it will definately say DG on the lens?

What are the differences between DG and non DG? not talking about the OS version.

Here is a picture of the label on my DG model of the Sigma EX 50-500mm f/4-6.3 APO DG HSM. The non DG is older and sometimes called the RF (rear focus) model. The DG is also RF but isn't labeled as such.

To quote Sigma:
"The DG designation applied to certain newer Sigma lenses (mostly wide angle and wide zoom type lenses) indicates that the lens is especially suited for use with digital SLR cameras. The DG lenses feature improved (more even) light distribution from image center to edge, especially at maximum aperture, compared to conventional fast wide angle lenses."

I don't know if it actually made any difference in practice or not. The pictures that I have seen of the RF lens suggest that the older non-DG model had a different finish on the barrel and different ribbing on the focus and zoom rings.

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Sigma added the DG designation to some of their lenses as Digital SLRs became more popular. Some of the lenses were updated with special coating to help prevent flare. But from what I know most of the lenses were optically the same.

thanks. i actually ended up buying the non-dg version i was looking at but got the seller to knock another $100 off the price beause it was non dg. it's a decent performer on my 7D when I don't want to risk lugging my 120-300 around out to 400mm its definately sharp enough< then starts too fall apart a bit unless stopped down to F8. I'm happy with it for what i paid though. And it gets me to 500mm, which none of my othe leses will do. I might save up for the OS version as this one has left a very positive impression for being 3 versions old.