[Ray Pulley]

Appearently, a version 1.03 is imminent, promised to fix the AF low light issue. This is news from after this thread started. You'll find clues within it.



I cannot check right now. Are you sure you looked up the AF spec rather than the metering spec? I asl because I remember the metering spec contains a reference to the lens which is logical too.

Yes,

The K10D and K20D both say EV -1 to 18 ISO 100 f1.4. The K5 does not mention f1.4 in the AF spec, only ISO 100, but all call this a brightness range, which I would normally think of as LV, not EV. LV does not make sense as it does not tell you much about how much light hit the AF system.

All of the service references I could find specify the AF adjustment process in LV, not EV, but that is because they use a calibrated light source that has to be set to make the test.

Anyway, as we all have seen over the years, what I call PEnglish or Pentax English often makes many things less than crystal clear.

So, given the ISO and f stop used on the older camera specs, at EV 0, f1.4, ISO 100, the shutter speed had to be 4 seconds.

Don't get me wrong, I tested my K5s with the FA50 f1.4 and did not see a huge difference from other lenses, but I only own fixed aperture lenses and only one slower than f2.8.

Ray

[Smeggypants]

So posters who claim to notice problems at EV4 are probably right.

My K-5 starts to FF just below EV4. Nothing 'probably' about it. It's a 'definitely'.

[Smeggypants]

Appearently, a version 1.03 is imminent, promised to fix the AF low light issue. This is news from after this thread started. You'll find clues within it.

Well, I'll believe it when I see it. The FW fix has been imminent for a month or so now.

I'm getting ready to buy a second K-5 body now, but won't until a fix is forthcoming.

[zackspeed]

I heard that the firmware will be available on 1st april.

Nope......sorry......

[ursamajor]

Appearently, a version 1.03 is imminent, promised to fix the AF low light issue.

Imminent? It's so from december...

[Eric Seavey]

I would like to express my appreciation to Falk for all his effort studying the FF problem.

Many of us have done tests and easily confirmed the issue and conditions at which it happens. The only problem with that is that the problem had not been quantified and compared against specifications. This is important because the only way an engineer at Pentax can effectively determine whether a problem is a real one or just unreasonable user expectations.

I read and understood Falk's report and am glad the FF issue has been quantified, supporting the need for this to be addressed.

[the swede]

I would like to express my appreciation to Falk for all his effort studying the FF problem.

Many of us have done tests and easily confirmed the issue and conditions at which it happens. The only problem with that is that the problem had not been quantified and compared against specifications. This is important because the only way an engineer at Pentax can effectively determine whether a problem is a real one or just unreasonable user expectations.

I read and understood Falk's report and am glad the FF issue has been quantified, supporting the need for this to be addressed.

Well written of you, an exellent post!

[normhead]

Question for falconeye on his FF report.
Quote:

The effect is real and can negatively impact the daily work of a photographer. On the other hand, it is possible to run into a low light tungsten situation without the problem.

No doubt a great effort and lots of time devoted to this, and thanks for that.. but could this statement not have also been written as

"The effect is real but may not negatively impact the daily work of a photographer. It is possible to run into a low light tungsten situation without the problem."

ANd to put this into context of what percentage of the average photographers work this might affect? As I just posted in another thread, the effect on me of this problem is zero. I work mostly outdoors, almost always in available light. I suspect that this is a relatively isolated problem that affects very few professional photographers and even fewer amateurs. But hey, I'm not the expert.

I'm always leery of technical reports of limited focus and relatively obscure problems being taken way out of context by undiscerning users.

Just askin
__________________

[Smeggypants]

Question for falconeye on his FF report.
Quote:

No doubt a great effort and lots of time devoted to this, and thanks for that.. but could this statement not have also been written as

The effect is real and can negatively impact the daily work of a photographer. On the other hand, it is possible to run into a low light tungsten situation without the problem.

"The effect is real but may not negatively impact the daily work of a photographer. It is possible to run into a low light tungsten situation without the problem."

Why? Falc's statement doesn't say it will definitely ( or always ) affect the work of a photographer, it just says it can. And indeed it can

I don't understand your reasoning?

ANd to put this into context of what percentage of the average photographers work this might affect? As I just posted in another thread, the effect on me of this problem is zero. I work mostly outdoors, almost always in available light. I suspect that this is a relatively isolated problem that affects very few professional photographers and even fewer amateurs. But hey, I'm not the expert.

I'm always leery of technical reports of limited focus and relatively obscure problems being taken way out of context by undiscerning users.

Just askin
__________________

So becuase it doesn't affect you it's a 'relatively obscure' problem and taken way out of context? And who are you to say who is undiscerning?

FWIW, I also work mostly outdoors, almost always in available light, and this front focus issue is a big problem for me.

And from what I've seen the FF issue certainly isn't relatively isolated.

I didn't have the sensor stain problem, but I wouldn't dare claim that the issue was relatively obscure or worse imply that those with the problem were undiscerning.

I also take issue with your claim it would affect 'fewer amateurs'. What rationale dictates that Amateurs take fewer photographs in lower light?

Surely if the problem doesn't affect you then why are you trying to minimise it for the rest of us? btw - have you actually compared the performance of your K-5's Phase and Contrast AF systems at EV2 ?

[Smeggypants]

According to page 358 of the manual, the metering spec is "EV0 to 22 (ISO 100 50mm f1.4)"

According to page 358 of the manual, the exposure compensation spec is "EV0 to 22 (ISO 100 50mm f1.4)"

[explosive]

ANd to put this into context of what percentage of the average photographers work this might affect? As I just posted in another thread, the effect on me of this problem is zero. I work mostly outdoors, almost always in available light. I suspect that this is a relatively isolated problem that affects very few professional photographers and even fewer amateurs. But hey, I'm not the expert.

I'm always leery of technical reports of limited focus and relatively obscure problems being taken way out of context by undiscerning users.

Just askin

Fine it doesn't affect your photography, but don't disregard a fairly major issue because of that.

My £100 P&S camera can take photos inside with ease. My £1,000 camera can't because it front focuses in low light - thats a fairly major problem.

Please don't put down a problem just because you never see it in your type of photography.

[dadipentak]

Please don't put down a problem just because you never see it in your type of photography.

I think that's right. This issue has not interfered with my photography or enthusiasm for the K-5 (yet--it might down the road) but I'm all in favor of its being resolved.

[explosive]

Oh it hasn't interfered with my enthusiasm for my K5 dadipentak. Its disappointed me when shooting inside and low light. Now I just wait patiently for the so called fix....

[Michaelina2]

According to page 358 of the manual, the exposure compensation spec is "EV0 to 22 (ISO 100 50mm f1.4)"

Easy... Simply move the goal post!

Admit there's a typo in the manual, adjust the spec, and BINGO... no problem!!

Cheers... M

[gazonk]

Easy... Simply move the goal post!

Admit there's a typo in the manual, adjust the spec, and BINGO... no problem!!

Cheers... M

Reminds me of "How many Microsoft Engineers does it take to change a light bulb?" "Zero, since Bill Gates will define darkness as a new standard".