Missing something can't set ISO below 160?

vievetrick · 11-27-2010, 01:23 PM

Hi everyone, had some time today to play with the setting on the K5. I am having strange problem. More like I am simply missing the obvious. Yes I am using the manual Page 94-97. I can not get the ISO below 160

what am I missing

Pentak k5 iso setting | Flickr - Photo Sharing!

PS how can I embed a Flickr video here. I am batting 100 today for sure.

Kunzite · 11-27-2010, 01:31 PM

Menu/D-Range Setting: Highlight Correction is On.

Roberts · 11-27-2010, 01:33 PM

I think you turned on Highlight Correction function. Find it in Menu or INFO Menu and turn off.

vievetrick · 11-27-2010, 01:33 PM

I knew I would have the answer quick if I posted it here. That was it!! :-) Thanks a lot!! About to head out for some night shots and wanted ISO 100 at least. Thanks again. I knew it was something I tweaked and just couldn't figure out how to get back.

falconeye · 11-28-2010, 07:14 PM

Originally posted by vievetrick

I knew I would have the answer quick if I posted it here. That was it!! :-) Thanks a lot!! About to head out for some night shots and wanted ISO 100 at least. Thanks again. I knew it was something I tweaked and just couldn't figure out how to get back.

Just to confuse you a bit more ...

ISO 160 with Highlight correction ON still is ISO 80 actually. But only parts of the image which would overexpose at Highlight correction OFF benefit from the low ISO properties. All other parts would be 1 stop underexposed at ISO 80 which is why the camera tells you to be at ISO 160 (which is wrong actually and the core reason you cannot switch to 80: you already are in 80...).

If you want to shoot with high dynamic range (like a night scene), you actually may want to use Highlight correction ON with ISO 160 to get the full dynamic range of ISO 80 but with the extra headroom shifted 1 stop from the shadows towards the highlights. There still is ample headroom in the shadows left and less blown highlights. Of course, nothing a simple EV compensation wouldn't do too ...

**jpzk** · 11-28-2010, 08:17 PM

Originally posted by falconeye

Just to confuse you a bit more ...

ISO 160 with Highlight correction ON still is ISO 80 actually. But only parts of the image which would overexpose at Highlight correction OFF benefit from the low ISO properties. All other parts would be 1 stop underexposed at ISO 80 which is why the camera tells you to be at ISO 160 (which is wrong actually and the core reason you cannot switch to 80: you already are in 80...).

If you want to shoot with high dynamic range (like a night scene), you actually may want to use Highlight correction ON with ISO 160 to get the full dynamic range of ISO 80 but with the extra headroom shifted 1 stop from the shadows towards the highlights. There still is ample headroom in the shadows left and less blown highlights. Of course, nothing a simple EV compensation wouldn't do too ...

So Falk,
What would you set the K5 at to get a maximum DR for:
1. a well lit scene - outside/sunny day
2. an evening/night scene with lots of "Christmas lights".
Wouldn't it be as simple as just leaving the ISO settings at 80 (no highlights correction) and "play" with Ev comp.?

JP

falconeye · 11-29-2010, 09:03 AM

Originally posted by jpzk

Wouldn't it be as simple as just leaving the ISO settings at 80 (no highlights correction) and "play" with Ev comp.?

Yes, what I do actually.
But some are then confused by the underexposed-looking JPG preview and histogram.

**jpzk** · 11-29-2010, 11:42 AM

Originally posted by falconeye

Yes, what I do actually.
But some are then confused by the underexposed-looking JPG preview and histogram.

Alright then.
That answers my question.
Thanks.

JP

Rick Clark · 11-29-2010, 01:30 PM

Read page 96 of the user manual for ISO 160

Eruditass · 11-29-2010, 09:22 PM

Originally posted by falconeye

Just to confuse you a bit more ...

ISO 160 with Highlight correction ON still is ISO 80 actually. But only parts of the image which would overexpose at Highlight correction OFF benefit from the low ISO properties. All other parts would be 1 stop underexposed at ISO 80 which is why the camera tells you to be at ISO 160 (which is wrong actually and the core reason you cannot switch to 80: you already are in 80...).

I wouldn't call it ISO 80. The only part of the image that is ISO 80 is upper part of the highlights. The rest, including middle gray (which I feel, if anything, should determine the "sensitivity"), is boosted by one stop, making it ISO 160. It doesn't matter if it is done digitally, it's the final medium's sensitivity. Unless you want to call some of the higher ISO's whatever analog sensitivity it maxes out at.

In fact, it's probably closer to the film ISO 160 with its saturated highlight section.

falconeye · 11-30-2010, 03:33 AM

Originally posted by Eruditass

I wouldn't call it ISO 80. The only part of the image that is ISO 80 is upper part of the highlights. The rest, including middle gray (which I feel, if anything, should determine the "sensitivity"), is boosted by one stop, making it ISO 160. It doesn't matter if it is done digitally, it's the final medium's sensitivity. Unless you want to call some of the higher ISO's whatever analog sensitivity it maxes out at.

In fact, it's probably closer to the film ISO 160 with its saturated highlight section.

I agree.
It is still important to know though that the programmable analog gain is set to ISO 80, i.e. that the entire full well capacity is available rather than only half of it.

freddyhard · 12-10-2010, 07:14 AM

from what experience i have i found i got less highlights clipped when i had the dynamic range set to 200 on my K20. i imagine it would be the same with the K5, although users seem to disagree here. so what about the shadow correction setting, should that be left off as well?

falconeye · 12-10-2010, 07:46 AM

Originally posted by freddyhard

from what experience i have i found i got less highlights clipped when i had the dynamic range set to 200 on my K20.

Not for RAW and according to DxO. Both ISO 100 and 200 are measured to be about 86% of true ISO which is defined via the clipping level.

freddyhard · 12-10-2010, 08:47 AM

Originally posted by falconeye

Originally posted by freddyhard

from what experience i have i found i got less highlights clipped when i had the dynamic range set to 200 on my K20. i imagine it would be the same with the K5, although users seem to disagree here. so what about the shadow correction setting, should that be left off as well?

Not for RAW and according to DxO. Both ISO 100 and 200 are measured to be about 86% of true ISO which is defined via the clipping level.

a lot of my photos are action shots so i normally save as jpg's. i only use RAW when i cannot get the white balance or when i know the exposure will be tricky - infrared or sunsets. that said, i was asking about the shadow correction. should that be left off?

Eruditass · 12-10-2010, 08:53 AM

Originally posted by freddyhard

a lot of my photos are action shots so i normally save as jpg's. i only use RAW when i cannot get the white balance or when i know the exposure will be tricky - infrared or sunsets. that said, i was asking about the shadow correction. should that be left off?

Depends on what you want. It will only boost the shadows, having no affect on the highlights or midtones (save perceived contrast).

11-27-2010, 01:23 PM	#1
vievetrick Veteran Member Join Date: Sep 2006 Location: Easthampton - Massachusetts - USA Photos: Gallery Posts: 5,183	Missing something can't set ISO below 160? Hi everyone, had some time today to play with the setting on the K5. I am having strange problem. More like I am simply missing the obvious. Yes I am using the manual Page 94-97. I can not get the ISO below 160 what am I missing Pentak k5 iso setting \| Flickr - Photo Sharing! PS how can I embed a Flickr video here. I am batting 100 today for sure.

11-28-2010, 07:14 PM	#5
falconeye Veteran Member Join Date: Jan 2008 Location: Munich, Alps, Germany Photos: Gallery Posts: 6,871	Originally posted by vievetrick I knew I would have the answer quick if I posted it here. That was it!! :-) Thanks a lot!! About to head out for some night shots and wanted ISO 100 at least. Thanks again. I knew it was something I tweaked and just couldn't figure out how to get back. Just to confuse you a bit more ... ISO 160 with Highlight correction ON still is ISO 80 actually. But only parts of the image which would overexpose at Highlight correction OFF benefit from the low ISO properties. All other parts would be 1 stop underexposed at ISO 80 which is why the camera tells you to be at ISO 160 (which is wrong actually and the core reason you cannot switch to 80: you already are in 80...). If you want to shoot with high dynamic range (like a night scene), you actually may want to use Highlight correction ON with ISO 160 to get the full dynamic range of ISO 80 but with the extra headroom shifted 1 stop from the shadows towards the highlights. There still is ample headroom in the shadows left and less blown highlights. Of course, nothing a simple EV compensation wouldn't do too ... Last edited by falconeye; 11-28-2010 at 07:20 PM.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Architecture Structure 160	cdurfor	Post Your Photos!	1	11-07-2010 09:13 PM
For Sale - Sold: Pentax Bellows II M Set and Auto Extensions Tube Set K (US/CAN)	Nick	Sold Items	3	08-12-2010 07:07 PM
Setting ISO 160 on analog dial?	CSoars	Film SLRs and Compact Film Cameras	5	12-24-2008 03:28 PM
Why does ev compensation set off auto iso?	jake123	Pentax DSLR Discussion	12	02-29-2008 07:29 AM
How's this for $160...	SupremeMoFo	Photographic Technique	3	10-08-2007 07:02 AM

11-27-2010, 01:31 PM	#2
Kunzite Pentaxian Join Date: Apr 2007 Location: Romania Posts: 15,132	Menu/D-Range Setting: Highlight Correction is On.

11-27-2010, 01:33 PM	#3
Roberts Senior Member Join Date: Apr 2008 Location: Latvia Photos: Gallery Posts: 127	I think you turned on Highlight Correction function. Find it in Menu or INFO Menu and turn off.

11-28-2010, 08:17 PM	#6
jpzk Site Supporter Join Date: Jan 2009 Location: Québec Photos: Gallery \| Albums Posts: 8,251	Originally posted by falconeye Just to confuse you a bit more ... ISO 160 with Highlight correction ON still is ISO 80 actually. But only parts of the image which would overexpose at Highlight correction OFF benefit from the low ISO properties. All other parts would be 1 stop underexposed at ISO 80 which is why the camera tells you to be at ISO 160 (which is wrong actually and the core reason you cannot switch to 80: you already are in 80...). If you want to shoot with high dynamic range (like a night scene), you actually may want to use Highlight correction ON with ISO 160 to get the full dynamic range of ISO 80 but with the extra headroom shifted 1 stop from the shadows towards the highlights. There still is ample headroom in the shadows left and less blown highlights. Of course, nothing a simple EV compensation wouldn't do too ... So Falk, What would you set the K5 at to get a maximum DR for: 1. a well lit scene - outside/sunny day 2. an evening/night scene with lots of "Christmas lights". Wouldn't it be as simple as just leaving the ISO settings at 80 (no highlights correction) and "play" with Ev comp.? JP

11-29-2010, 09:03 AM	#7
falconeye Veteran Member Join Date: Jan 2008 Location: Munich, Alps, Germany Photos: Gallery Posts: 6,871	Originally posted by jpzk Wouldn't it be as simple as just leaving the ISO settings at 80 (no highlights correction) and "play" with Ev comp.? Yes, what I do actually. But some are then confused by the underexposed-looking JPG preview and histogram.

11-29-2010, 11:42 AM	#8
jpzk Site Supporter Join Date: Jan 2009 Location: Québec Photos: Gallery \| Albums Posts: 8,251	Originally posted by falconeye Yes, what I do actually. But some are then confused by the underexposed-looking JPG preview and histogram. Alright then. That answers my question. Thanks. JP

11-29-2010, 01:30 PM	#9
Rick Clark Senior Member Join Date: Nov 2010 Location: Provo, Utah Posts: 128	Read page 96 of the user manual for ISO 160

11-29-2010, 09:22 PM	#10
Eruditass Veteran Member Join Date: Jul 2009 Photos: Gallery Posts: 2,207	Originally posted by falconeye Just to confuse you a bit more ... ISO 160 with Highlight correction ON still is ISO 80 actually. But only parts of the image which would overexpose at Highlight correction OFF benefit from the low ISO properties. All other parts would be 1 stop underexposed at ISO 80 which is why the camera tells you to be at ISO 160 (which is wrong actually and the core reason you cannot switch to 80: you already are in 80...). I wouldn't call it ISO 80. The only part of the image that is ISO 80 is upper part of the highlights. The rest, including middle gray (which I feel, if anything, should determine the "sensitivity"), is boosted by one stop, making it ISO 160. It doesn't matter if it is done digitally, it's the final medium's sensitivity. Unless you want to call some of the higher ISO's whatever analog sensitivity it maxes out at. In fact, it's probably closer to the film ISO 160 with its saturated highlight section.

11-30-2010, 03:33 AM	#11
falconeye Veteran Member Join Date: Jan 2008 Location: Munich, Alps, Germany Photos: Gallery Posts: 6,871	Originally posted by Eruditass I wouldn't call it ISO 80. The only part of the image that is ISO 80 is upper part of the highlights. The rest, including middle gray (which I feel, if anything, should determine the "sensitivity"), is boosted by one stop, making it ISO 160. It doesn't matter if it is done digitally, it's the final medium's sensitivity. Unless you want to call some of the higher ISO's whatever analog sensitivity it maxes out at. In fact, it's probably closer to the film ISO 160 with its saturated highlight section. I agree. It is still important to know though that the programmable analog gain is set to ISO 80, i.e. that the entire full well capacity is available rather than only half of it.

12-10-2010, 07:14 AM	#12
freddyhard Inactive Account Join Date: Aug 2010 Posts: 10	from what experience i have i found i got less highlights clipped when i had the dynamic range set to 200 on my K20. i imagine it would be the same with the K5, although users seem to disagree here. so what about the shadow correction setting, should that be left off as well?

12-10-2010, 07:46 AM	#13
falconeye Veteran Member Join Date: Jan 2008 Location: Munich, Alps, Germany Photos: Gallery Posts: 6,871	Originally posted by freddyhard from what experience i have i found i got less highlights clipped when i had the dynamic range set to 200 on my K20. Not for RAW and according to DxO. Both ISO 100 and 200 are measured to be about 86% of true ISO which is defined via the clipping level.

12-10-2010, 08:47 AM	#14
freddyhard Inactive Account Join Date: Aug 2010 Posts: 10	Originally posted by falconeye Originally posted by freddyhard from what experience i have i found i got less highlights clipped when i had the dynamic range set to 200 on my K20. i imagine it would be the same with the K5, although users seem to disagree here. so what about the shadow correction setting, should that be left off as well? Not for RAW and according to DxO. Both ISO 100 and 200 are measured to be about 86% of true ISO which is defined via the clipping level. a lot of my photos are action shots so i normally save as jpg's. i only use RAW when i cannot get the white balance or when i know the exposure will be tricky - infrared or sunsets. that said, i was asking about the shadow correction. should that be left off?

12-10-2010, 08:53 AM	#15
Eruditass Veteran Member Join Date: Jul 2009 Photos: Gallery Posts: 2,207	Originally posted by freddyhard a lot of my photos are action shots so i normally save as jpg's. i only use RAW when i cannot get the white balance or when i know the exposure will be tricky - infrared or sunsets. that said, i was asking about the shadow correction. should that be left off? Depends on what you want. It will only boost the shadows, having no affect on the highlights or midtones (save perceived contrast).