Sigma 28-70 f2.8 manual focus distance scale jump

Started 3 months ago | Discussions
DimLS Regular Member • Posts: 168
Sigma 28-70 f2.8 manual focus distance scale jump
1

Hello,

I just got sigma 28-70 f2.8 for my Lumix S1. Everything is nice except from the following:

1 At manual focus mode, the focus is moving is small steps. I guess it’s the way it’s designed. I have seen it in 2 Olympus lenses as well.

2. Here is the main problem, at e.g. 35mm when rotating the focusing ring, the focus indicator is jumping from about 4m to 15m (and the opposite). I feel the real jump is smaller though. Then you are at 50mm it makes a smaller jump and somewhere at about 10m. So when going from 28 to 70mm the gap is gettin smaller. I think this is a problem.I sometimes use distance scale to focus.

3. This may  not be a design problem. The distance scale focus indicator shifts with focal length. E.g at 70mm when you focus to real distance 5 m it shows the focus indication to 5m. But then you go wider, for the same real distance the indicator shows 10m! This is a huge shift and can make the manual prefocus using the scale totally useless.

For point 2, do you see any similar operation?

Thank you

Panasonic S1
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rashid7
rashid7 Veteran Member • Posts: 6,292
Re: Sigma 28-70 f2.8 manual focus distance scale jump

Focus distance scales are to be taken w/ some skepticism, i believe.

I am interested in this lens, and if this is the worst of yours - I'd be pleased!

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OP DimLS Regular Member • Posts: 168
Re: Sigma 28-70 f2.8 manual focus distance scale jump

rashid7 wrote:

Focus distance scales are to be taken w/ some skepticism, i believe.

I am interested in this lens, and if this is the worst of yours - I'd be pleased!

You probably are right. The lens is amazing, in general very sharp all over the frame and focal lengths, and apertures? great contrast. Great haptics and very nice size. I was checking sharpness at 2.8 at edges and center, and double checked if I was at 50% magnification (I was at 100%)

I have yet to evaluate bokeh, focus reliability.

This lens should be a keeper, at least if you get a good copy

rashid7
rashid7 Veteran Member • Posts: 6,292
Re: Sigma 28-70 f2.8 manual focus distance scale jump

This is encouraging, thanks.  Mine on order from adorama since one month ago

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