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02-12-2016, 05:45 PM - 1 Like   #1
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K-3 Auto Focus

I knew my K-3 focused better than my K-5 but did not realize how much better till today. My daughter has the K-5 now and we were out shooting at a 100+ year old Iron Furnace she was trying to get a shot and the K-5 just would not focus even with the assist lamp on (I have never had it on in the K-3). We were both shooting F/2.8 lens I shot the same pic yesterday had to shoot F/2.8 1 sec exposure at ISO 6400 so it is dark but was really surprised it would not lock focus.
Here is the shot



Here is another K-5 would focus on either K-3 locked with out hunting at all


02-12-2016, 05:55 PM   #2
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You must think I'm being a total idiot here !

So, you said ISO 6400 ?
I thought at first this was rather "excellent", with little or no noise to be seen.
Then I checked the Flickr link for the first shot: ... says ISO 400 at f4.5 15s exposure ??
Help me understand .... did you or your daughter shoot at ISO 6400 ?

Thanks !

JP
02-12-2016, 06:00 PM   #3
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Nope said I shot the same pic yesterday and had to shoot those settings took tripod today

---------- Post added 02-12-16 at 07:03 PM ----------

QuoteOriginally posted by jpzk Quote
You must think I'm being a total idiot here !

So, you said ISO 6400 ?
I thought at first this was rather "excellent", with little or no noise to be seen.
Then I checked the Flickr link for the first shot: ... says ISO 400 at f4.5 15s exposure ??
Help me understand .... did you or your daughter shoot at ISO 6400 ?

Thanks !

JP
This is the one from yesterday not super sharp but not a focus issue 1 sec exposure hand held issue
02-13-2016, 04:44 AM   #4
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So the K-3 focuses better in low-light than K-5, but only in situations where you typically have to use a tripod and deal with a stationary subject anyway. Otherwise you would just use flash, in which case the AF assist lamp of the flash would help the camera to focus anyway.

02-13-2016, 07:06 AM   #5
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QuoteOriginally posted by starbase218 Quote
So the K-3 focuses better in low-light than K-5, but only in situations where you typically have to use a tripod and deal with a stationary subject anyway. Otherwise you would just use flash, in which case the AF assist lamp of the flash would help the camera to focus anyway.
Tripod does not help when you can not see to focus manually which was the case yesterday and a flash would not have been the answer I have seen many instances of my K-3 focusing much better even in well lit shots than my K-5. The K-3 runs circles around the K-5 when it comes to focusing much more accurate especially in low light this was an extreme example but even in less extreme cases focus is much faster with less hunting.
02-13-2016, 01:55 PM   #6
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QuoteOriginally posted by hangman43 Quote
Tripod does not help when you can not see to focus manually which was the case yesterday and a flash would not have been the answer I have seen many instances of my K-3 focusing much better even in well lit shots than my K-5. The K-3 runs circles around the K-5 when it comes to focusing much more accurate especially in low light this was an extreme example but even in less extreme cases focus is much faster with less hunting.
You say liveview couldn't even provide an image for you to manually focus on, yet PDAF still worked?

Last edited by starbase218; 02-13-2016 at 01:58 PM. Reason: I misunderstood
02-13-2016, 06:06 PM   #7
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QuoteOriginally posted by starbase218 Quote
You say liveview couldn't even provide an image for you to manually focus on, yet PDAF still worked?
Yes tried live view was not enough light to get focus could barely see anything
02-13-2016, 08:46 PM   #8
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Thanks for posting

Thanks Hangman.

I still have my K5 to go with my K3. The K3 definitely is substantially faster and more reliable than the K5. I've done macro in zoo's and the K5 was hopeless. I wanted to have a two camera setup so I wouldn't have to change lenses. Had to give up on that and keep shooting the K3.

The K5 has incredible image quality but if you are a more demanding shooter, the AF can and does let it down, particularly indoors and moderate to low light.

I am not surprised by your findings. It's actually very true to life!

Howie Be

02-16-2016, 01:53 PM   #9
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QuoteOriginally posted by starbase218 Quote
You say liveview couldn't even provide an image for you to manually focus on, yet PDAF still worked?
You say this as if you think CDaf will focus in lower light levels than PDaf !!

CD af currently is no where near the low light sensitivity of PD af , That is why most manufacturers wont even give figures in the camera spec.

The ability of CD af to not need calibrating for accurate AF has lead to many false assumptions on it ability, It is still the poor cousin to PD af

CD is a one trick pony with no other advantage over PD than the calibration requirements.

Because of the high gain required for liveview it fails for even MF long before an f2.8 lens reaches -3EV
02-17-2016, 04:17 AM   #10
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QuoteOriginally posted by awaldram Quote
You say this as if you think CDaf will focus in lower light levels than PDaf !!
Err, no. I specifically mentioned manually focusing using liveview (probably magnified).

But yes, I would be surprised if PDAF would focus more reliably than manually focusing using liveview. Positively surprised, that is.
02-17-2016, 10:55 AM   #11
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QuoteOriginally posted by awaldram Quote
You say this as if you think CDaf will focus in lower light levels than PDaf !!

CD af currently is no where near the low light sensitivity of PD af, That is why most manufacturers wont even give figures in the camera spec.

The ability of CD af to not need calibrating for accurate AF has lead to many false assumptions on it ability, It is still the poor cousin to PD af

CD is a one trick pony with no other advantage over PD than the calibration requirements.

Because of the high gain required for liveview it fails for even MF long before an f2.8 lens reaches -3EV
I believe Panasonic claims focusing capability to -4 EV on their current MILCs.
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