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06-07-2009, 09:35 AM   #1
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ISO improvement question?

With the introduction of the K7 and the improving ISO, does this mean that the speed advantage of the 1.8 77LTD over the 2.4 of the70LTD is no longer much of a factor? In other words, could a 70 on the K7 produce results equal to that of the 77 on the 20? I'm guessing that it also means even lower light results for the 77 on the K7?
Thoughts would be appreciated as I'm thinking (in one chubby guys opinion) that the size of the DA LTD's is becoming more of a factor over the FA LTD's?
thx

06-07-2009, 10:46 AM   #2
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What improving ISO are you talking about?
The K7 I had in hand was worse in noise compared to the K20.
Of course I expect the final firmware to compensate for that.
But there isn't much improvement.
If there would be, one would expect to see ISO 12.800 at least.

Regarding FA77 vs. DA70:
The FA is about 0.8 EV steps faster.
That gives you a shallower DoF. That's important.

I am no fan of the Limiteds in general.
If you are after small lenses ok, but else?
The DA Limiteds are optimized for smallness.
The FA Limiteds are good, but not exceptionally good.
They were designed for film.
Today they are overpriced.
06-07-2009, 11:23 AM   #3
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QuoteOriginally posted by blende8 Quote
What improving ISO are you talking about?
The K7 I had in hand was worse in noise compared to the K20.
Of course I expect the final firmware to compensate for that.
But there isn't much improvement.
If there would be, one would expect to see ISO 12.800 at least.

Regarding FA77 vs. DA70:
The FA is about 0.8 EV steps faster.
That gives you a shallower DoF. That's important.

I am no fan of the Limiteds in general.
If you are after small lenses ok, but else?
The DA Limiteds are optimized for smallness.
The FA Limiteds are good, but not exceptionally good.
They were designed for film.
Today they are overpriced.
Thanks for the response. Re the ISO, many are claiming that the ISO is a large improvement on the K7. Untill the units are shipped, I guess we won't know for sure. However, it they are better, would this mean that the speed advantage of a 1.8 over the 2.4 is no longer much of a factor? Re tje FA Ltd's not being "exceptionally good", you are one of the first I have heard that from.
06-07-2009, 12:14 PM   #4
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Like Wieland says if you're after shallow DOF, increasing ISO won't change that. But if you are just after usably fast shutter speeds for "normal" use, I personally think the advantage of f/1.8 over f/2.4 is *already* not as great as you'd think, because "most" of time, the DOF 77mm at f/1.8 is unusably small. Great if you're specifically after that effect, but since you are talking about raising ISO, I'm assuming you are thinking more about more "ordinary" shots in low light. As it is, I'm already hesitant to use the DA70 at f/2.4 because DOf is shallow enough as it is.

So I'm guessing any improvements - assuming there are some - in K-7 high ISO performance will be mostly a non-factor here. Those who absolutely require that extra fraction of stop for DOF reasons will continue to choose the FA77, those who avoid (again, for DOF reasons) shooting wider than f/2.8 unless absolutely necessary will continue to consider the DA70 a sensible alternative, and those who base the decision largely on bokeh, edge sharpness, "rendering", focus speed, weight, CA, price, or other factors will continue to choose the lens that happens to win on their favorite metric (the convetional wisom seems to be that FA77 wins on bokeh and "rendering", DA70 on edge sharpness, focus speed, and CA; no question the DA70 wins on weight and price).

06-08-2009, 05:41 AM   #5
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Thx for the feedback Marc and Blend8. Points that I hadn't considered. (Never ending learning curve!)
As more and more items make it in the camera bag, the small size of the DA's certainly becomes more appealing....

Last edited by beaumont; 06-08-2009 at 05:47 AM.
06-08-2009, 07:55 AM   #6
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I think the other advantage not really mentioned is the viewfinder brightness.

In low light, I find the bright viewfinder of my F1.4 lenses (SMC 50mm, and Vivitar 85mm) is a big plus.
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