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07-02-2015, 02:38 PM - 1 Like   #1
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Auto ISO won't go below 200 please help

Just been playing with my just arrived K3 and noticed no matter how bright it is out, the ISO setting won't go below 200 ISO.
I have it set to go from ISO 100-6400. Tried resetting it with the green button but that doesn't work

Any ideas?

Thanks

Randy

07-02-2015, 02:43 PM   #2
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Shadow or maybe highlight corrections.

Something like that.
07-02-2015, 02:48 PM   #3
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Yes you are right. It won't go below 200 with the highlight correction on.
Thanks for the help!

Randy
07-02-2015, 02:49 PM - 1 Like   #4
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As above, turn off Highlight and Shadow correction under the D-range menu in the camera setup screen.

07-02-2015, 07:27 PM   #5
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QuoteOriginally posted by crewl1 Quote
turn off Highlight and Shadow correction under the D-range menu in the camera setup screen.
Plus, if you shoot RAW exclusively, those settings won't do anything for you anyhow.
07-06-2015, 09:22 PM - 1 Like   #6
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QuoteOriginally posted by rawr Quote
Plus, if you shoot RAW exclusively, those settings won't do anything for you anyhow.
Sadly, some folks still don't understand the reality of the situation. In RAW, when highlight compensation is activated, the system is directed to underexpose by one stop and institute a very natural highlight roll-off to prevent blown highlights. This comes at a minor penalty to shadow noise. When Auto HC is instituted on the K-3, you will never see it instituted unless considerable clipping occurs (not minor specular clipping), As such, assuming that you use a proper quality converter that picks up the marker (LR, C1, DxO, the OEM, and several others), you will safeguard at least somewhat against blow-outs in high contrast scenes - and get an added roughly .8 EV dynamic range improvement in the process. Frankly, I wish Auto HC was a bit more aggressive such as how it was implemented on the K-30, K-01 and others, but Pentax decided to err in the expose to the right side of things - on a sensor that does not really need it.

Only Shadow Compensation has no effect on the RAW images. This always has been the case with Pentax, so the whole mythology behind the incorrect notions started so many years ago really needs to be dispelled.
07-07-2015, 09:42 AM   #7
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QuoteOriginally posted by ScooterMaxi Jim Quote
Sadly, some folks still don't understand the reality of the situation. In RAW, when highlight compensation is activated, the system is directed to underexpose by one stop and institute a very natural highlight roll-off to prevent blown highlights. This comes at a minor penalty to shadow noise. When Auto HC is instituted on the K-3, you will never see it instituted unless considerable clipping occurs (not minor specular clipping), As such, assuming that you use a proper quality converter that picks up the marker (LR, C1, DxO, the OEM, and several others), you will safeguard at least somewhat against blow-outs in high contrast scenes - and get an added roughly .8 EV dynamic range improvement in the process. Frankly, I wish Auto HC was a bit more aggressive such as how it was implemented on the K-30, K-01 and others, but Pentax decided to err in the expose to the right side of things - on a sensor that does not really need it.

Only Shadow Compensation has no effect on the RAW images. This always has been the case with Pentax, so the whole mythology behind the incorrect notions started so many years ago really needs to be dispelled.
Why is the ISO bumped to 200 with highlight compensation on?

Thanks

Randy
07-07-2015, 09:46 AM   #8
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QuoteOriginally posted by slip Quote
Why is the ISO bumped to 200 with highlight compensation on?
To give "headroom" for the feature to work.


Steve

07-07-2015, 09:35 PM - 1 Like   #9
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Steve is correct - it allows for that gentle roll off on the top end with a trade off of some added noise in the shadows. In other words, you could decide to set ISO at 200, underexpose to prevent blown highlights, and pull out the proper roll off in conversion. Frankly, the Pentax roll off direction given to the converter is so good, I'd rather let the camera decide - knowing that it will execute the HC only when absolutely necessary, and I always play with the curve on every image anyways. Yes, you can do this yourself, as well, but what happens if that great shot gets literally blown because you didn't remember to dial in an extra stop of underexposure? No getting it back.

In any event, it has been observed that Nikon adds in HC without the user knowing it. The higher DR claimed for Nikon in the DxO tests closely parallel what Pentax does when HC is switched on in Pentax. Not that this is such a terrible thing, but Pentaxians often want to do things in a "pure" way, but that is such an odd notion in the modern digital age. When it comes down to it, all RAW images are baked in some way or another.
07-18-2015, 06:34 PM   #10
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Thank you, guys! I found the answers I needed reading this thread. Thank you for supporting and answering questions in this forum!

-Pat Lasley
Proud K100D Owner
Proud K-x Owner
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