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09-22-2012, 04:00 PM   #1
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New Sigma Lenses to Feature User Focus Range and Micro AF Adjust

New Sigma lens models will allow the user to set custom AF limits and adjust AF focus depending on focal length and subject distance!

That's an amazing announcement, AFAIC!

09-22-2012, 04:41 PM   #2
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QuoteOriginally posted by Class A Quote
New Sigma lens models will allow the user to set custom AF limits and adjust AF focus depending on focal length and subject distance!

That's an amazing announcement, AFAIC!

Pentax M lenses let you adjust the MF focus depending on the subject distance!
09-22-2012, 04:44 PM   #3
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QuoteOriginally posted by Class A Quote
New Sigma lens models will allow the user to set custom AF limits and adjust AF focus depending on focal length and subject distance!

That's an amazing announcement, AFAIC!
Really amazing. Pentax should allow us to do that too.
09-22-2012, 04:52 PM   #4
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I'm glad to see Sigma is keeping current and innovative. A selectable focus range would be extremely useful at airshows, for instance. As long as it's easy to set a long lens like a 150-500 to focus beyond x meters this would be quite attractive.

09-22-2012, 06:52 PM   #5
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No kidding! Have you seen the "rough example" of the (computer) interface to be able to micro-adjust focus for a zoom at different focal lengths and different focal distances!?



Just crazy good stuff. Sadly, I fully expect Sigma's "new" 120-300mm/2.8 with this function (also weather-sealed, with HSM & OS) will be just like the previous models and never be made with a K-mount on the back... We're just a small (and shrinking) marketshare, and I'm sure Sigma sees "no compelling business case" for Pentax users to buy a full-frame lens like that one. (And before you jump in - yes, I see the reasons to buy a lens like this for APS-C!)

Last edited by panoguy; 09-22-2012 at 06:58 PM.
09-22-2012, 07:55 PM   #6
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Neat stuff panoguy!

Unfortunately I agree though that we will never see it for Pentax.
09-22-2012, 08:01 PM   #7
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QuoteOriginally posted by Class A Quote
New Sigma lens models will allow the user to set custom AF limits and adjust AF focus depending on focal length and subject distance!

That's an amazing announcement, AFAIC!
This is just too cool !

I've logged to the link you provided and sure enough: you can even adjust according to your needs, in three ways: no focus limit, default focus limit or custom focus limit. That's quite a serious advancement!
And, it also says that this same software wil allow for BF/FF adjusting as well.

Thanks for sharing.

JP
09-23-2012, 05:54 AM   #8
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With current bodies, it will be a challenge to determine the focus adjust needed at infinity.
A LensAlign or Lenscal won't be much use for that.

What would be really nice would be some focus adjust assistance in the firmware.
You have your camera and lens set up on a tripod,
with the center spot aimed at a contrasty target.
Enter "focus adjust assistance" in the menu.
The camera compares phase-detect and contrast-detect focus for the target,
and tells you what adjustment is needed.

09-23-2012, 06:01 AM   #9
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I started a thread a last week regarding this.

Nice software there.. but I think the optics are still the old designs but with a new makeover physically and with the USB port.

I expect they'll update theri complete lineup with these features. It's a that I bought a 50, 85 & 150 just a few months ago.
09-23-2012, 06:02 AM   #10
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QuoteOriginally posted by lytrytyr Quote
With current bodies, it will be a challenge to determine the focus adjust needed at infinity.
A LensAlign or Lenscal won't be much use for that.

What would be really nice would be some focus adjust assistance in the firmware.
You have your camera and lens set up on a tripod,
with the center spot aimed at a contrasty target.
Enter "focus adjust assistance" in the menu.
The camera compares phase-detect and contrast-detect focus for the target,
and tells you what adjustment is needed.
The only trouble I have with that idea is that I have at least one lens which doesn't focus very well in Live View. I forget which one it is unfortunately.

It's definitely the way to go and Sigma are to be commended for this.
09-23-2012, 06:11 AM   #11
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QuoteOriginally posted by bossa Quote
The only trouble I have with that idea is that I have at least one lens which doesn't focus very well in Live View. I forget which one it is unfortunately.
Is that on the K5?
09-23-2012, 06:38 AM   #12
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QuoteOriginally posted by bossa Quote
I expect they'll update their complete lineup with these features.
The interview mentioned "Contemporary," "Art," and "Sport" categories.
Seemed like "Contemporary" meant "low-budget consumer lens,"
so I wouldn't expect the adjustment feature in those.
09-23-2012, 06:47 AM   #13
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Sigma rullez!
09-23-2012, 08:11 AM   #14
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QuoteOriginally posted by lytrytyr Quote
Is that on the K5?
I don't remember which lens/brand. I'll look at my test shots and get back to you.
09-23-2012, 08:59 AM   #15
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Impressive. They also recently announced more extensive MTF testing during production in the factory. Sigma is on the right track. The DP2M looks nice as well.

Last edited by jeffshaddix; 09-23-2012 at 09:13 AM.
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