Program Line / Auto ISO Parameters guide?

Jeff Charles · 02-14-2012, 10:27 AM

I have been working to understand how my K-5's Program Line and Auto ISO Parameters interact. I have made progress by trying different combinations, but I'd like to find a guide or tutorial on the subject. Does one exist? I've searched, but have not found anything.

Jeff

rvannatta · 02-14-2012, 10:48 AM

Originally posted by Jeff Charles

I have been working to understand how my K-5's Program Line and Auto ISO Parameters interact. I have made progress by trying different combinations, but I'd like to find a guide or tutorial on the subject. Does one exist? I've searched, but have not found anything.

Jeff

Good luck. I've kinda given up undertand and want a little bit more predicitibility, so I simply dial in the ISO using the ISO button.

Fogel70 · 02-15-2012, 12:43 PM - **2 Likes**

These are my understanding on how PL works after some testings, but there are probably some things that I have missed.

In all PL except "Hi-Speed priority" auto ISO seems to work the same way, and ISO is selected to get shutter speed of 1/focal length*1.5*(Auto ISO mode).
(Auto ISO mode: Normal = 1, Slow = 0.5, Fast = 2)

In "Hi-Speed priority" PL the shutter speed do not wary with focal length, but as long as ISO can be raised it will keep shutter speed of 1/250s or faster.
(Auto ISO mode: Normal = 1/500 - 1/1000s, Slow = 1/250 - 1/500s, Fast = 1/1000s or faster) These are probably not the exact figures as there might be more factors that interact with "Hi-Speed priority" PL, and I might not remember the exact figures.

Also note that PL only fully works with P-Mode set to Program-Shift, not in Hyper-Program. In Hyper-Program the PL is only used when using default exposure settings, and if user override exposure settings the camera will go into Hyper-Av or Hyper-Tv modes which do not use PL. If using Program-Shift the chosen PL is still active when shifting exposure.

Jeff Charles · 02-16-2012, 09:44 AM

Originally posted by Fogel70

These are my understanding on how PL works after some testings, but there are probably some things that I have missed.

In all PL except "Hi-Speed priority" auto ISO seems to work the same way, and ISO is selected to get shutter speed of 1/focal length*1.5*(Auto ISO mode).
(Auto ISO mode: Normal = 1, Slow = 0.5, Fast = 2)

In "Hi-Speed priority" PL the shutter speed do not wary with focal length, but as long as ISO can be raised it will keep shutter speed of 1/250s or faster.
(Auto ISO mode: Normal = 1/500 - 1/1000s, Slow = 1/250 - 1/500s, Fast = 1/1000s or faster) These are probably not the exact figures as there might be more factors that interact with "Hi-Speed priority" PL, and I might not remember the exact figures.

Also note that PL only fully works with P-Mode set to Program-Shift, not in Hyper-Program. In Hyper-Program the PL is only used when using default exposure settings, and if user override exposure settings the camera will go into Hyper-Av or Hyper-Tv modes which do not use PL. If using Program-Shift the chosen PL is still active when shifting exposure.

Thanks. That helps. I've got nothing against automated features. I just like to understand exactly what they are doing. My goal is to set up User Modes for quick access in different situations.

I noticed that even after shifting to Hyper-Av, the Auto ISO Parameter is still effective, but it is not with Hyper-Tv.

Jeff

02-14-2012, 10:27 AM	#1
Jeff Charles Senior Member Join Date: Nov 2006 Location: Oaxaca, Mexico; Shohola PA, USA Posts: 219	Program Line / Auto ISO Parameters guide? I have been working to understand how my K-5's Program Line and Auto ISO Parameters interact. I have made progress by trying different combinations, but I'd like to find a guide or tutorial on the subject. Does one exist? I've searched, but have not found anything. Jeff

02-15-2012, 12:43 PM - 2 Likes	#3
Fogel70 Pentaxian Join Date: Sep 2009 Location: Stockholm, Sweden Photos: Albums Posts: 3,062	These are my understanding on how PL works after some testings, but there are probably some things that I have missed. In all PL except "Hi-Speed priority" auto ISO seems to work the same way, and ISO is selected to get shutter speed of 1/focal length1.5(Auto ISO mode). (Auto ISO mode: Normal = 1, Slow = 0.5, Fast = 2) In "Hi-Speed priority" PL the shutter speed do not wary with focal length, but as long as ISO can be raised it will keep shutter speed of 1/250s or faster. (Auto ISO mode: Normal = 1/500 - 1/1000s, Slow = 1/250 - 1/500s, Fast = 1/1000s or faster) These are probably not the exact figures as there might be more factors that interact with "Hi-Speed priority" PL, and I might not remember the exact figures. Also note that PL only fully works with P-Mode set to Program-Shift, not in Hyper-Program. In Hyper-Program the PL is only used when using default exposure settings, and if user override exposure settings the camera will go into Hyper-Av or Hyper-Tv modes which do not use PL. If using Program-Shift the chosen PL is still active when shifting exposure. Last edited by Fogel70; 02-15-2012 at 12:56 PM.

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02-14-2012, 10:48 AM	#2
rvannatta Pentaxian Join Date: Aug 2007 Location: Apiary, Oregon Photos: Gallery Posts: 1,181	Originally posted by Jeff Charles I have been working to understand how my K-5's Program Line and Auto ISO Parameters interact. I have made progress by trying different combinations, but I'd like to find a guide or tutorial on the subject. Does one exist? I've searched, but have not found anything. Jeff Good luck. I've kinda given up undertand and want a little bit more predicitibility, so I simply dial in the ISO using the ISO button.

02-16-2012, 09:44 AM	#4
Jeff Charles Senior Member Join Date: Nov 2006 Location: Oaxaca, Mexico; Shohola PA, USA Posts: 219 Original Poster	Originally posted by Fogel70 These are my understanding on how PL works after some testings, but there are probably some things that I have missed. In all PL except "Hi-Speed priority" auto ISO seems to work the same way, and ISO is selected to get shutter speed of 1/focal length1.5(Auto ISO mode). (Auto ISO mode: Normal = 1, Slow = 0.5, Fast = 2) In "Hi-Speed priority" PL the shutter speed do not wary with focal length, but as long as ISO can be raised it will keep shutter speed of 1/250s or faster. (Auto ISO mode: Normal = 1/500 - 1/1000s, Slow = 1/250 - 1/500s, Fast = 1/1000s or faster) These are probably not the exact figures as there might be more factors that interact with "Hi-Speed priority" PL, and I might not remember the exact figures. Also note that PL only fully works with P-Mode set to Program-Shift, not in Hyper-Program. In Hyper-Program the PL is only used when using default exposure settings, and if user override exposure settings the camera will go into Hyper-Av or Hyper-Tv modes which do not use PL. If using Program-Shift the chosen PL is still active when shifting exposure. Thanks. That helps. I've got nothing against automated features. I just like to understand exactly what they are doing. My goal is to set up User Modes for quick access in different situations. I noticed that even after shifting to Hyper-Av, the Auto ISO Parameter is still effective, but it is not with Hyper-Tv. Jeff