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06-24-2019, 07:28 PM   #16
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QuoteOriginally posted by reh321 Quote
the camera is trying to tell you something, and that something is conveyed by the text as well as by the color.

I was in Auto ISO, but because I was in Av mode, I was also in Auto Shutter Speed .... aperture is the only parameter the camera had to keep fixed, so it chose to vary shutter speed and keep ISO at the lowest possible value,
It's just not what my experience of Av mode does is all. You said;

"When I set my KP to Av mode, it keeps ISO at 100 and continually lowers shutter speed; when using LV and shutter speed gets down to 8" the three exposure parameters start flashing red"

Normally when my shutter speeds get down to around 1/50 or 1/25 (depending on lens attached), it halts and doesn't drop any lower, now what happens is the shutter speed stays fixed (for awhile) and the ISO starts to raise. Once my settings shift from say 1/25 ISO 100 to being 1/25 ISO 3200 (my self imposed Auto ISO limit) it would then drop the shutter speeds further down and keep the ISO still at 3200. All of this purposeful and how I want that mode to work for me.

If you're getting down to 8 second long exposures and ISO still at 100... that makes me believe you accidentally fixed ISO to being 100 and it had no choice other than to drop down to as low as 8 seconds...

QuoteOriginally posted by photoptimist Quote
Your KP is fine. It's the K-1 that has the bug. In LV mode, the K-1 does not warn the user that the light level is too low to be metered.

In LV mode with an f/2.8 lens, TAv set to 1sec f/2.8 putting the lens cap on pushes the ISO to 25600 but no higher. But there's no blinking and the histogram shows gross under-exposure. Changing the shutter speed or aperture causes the usual counter-adjustments of ISO with no blinking/red text, but the scene is still grossly under-exposed

In ordinary OVF metering with the K-1, TAv set to 1sec f/2.8 shows ISO climbing as the lens cap slowly goes on, seems to show valid exposures up to ISO 1600, starts blinking at ISO 2200, and gets no higher than ISO 4500 (and blinking) with the lens and OVF totally in the dark.

(NOTE: this behavior does depend on the max aperture of the lens -- whatever algorithms are used for AE in both LV and OVF know this aperture and use it to adjust the results)

P.S. The K-5 acts more like the KP for AE in LV mode -- if the scene gets too dark, the K-5 shows blinking red exposure values.
Excellent, this makes more sense, K-1 bug hehe. I wonder if the K-1ii is any different in this regard. Because yeah, we have KP users, K3, K-5 and Ks2 all doing the same thing. I'm just so used to using my K-1 (60,000 shutter actuations) that I seldom use the KP in scenarios like in my home panning around a room with dim lighting, it just struck me as odd to see that red flashing. I can sleep easier now that I know why.

Thanks again!

06-24-2019, 10:43 PM   #17
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QuoteOriginally posted by BruceBanner Quote
Have you any source to back this up? Not that I'm doubting you, but the K-1 has never ever went red blinky text. Same room dynamics and it wouldn't change from white text info, it simply worked within my ISO Parameters, when it hit 3200 ISO it stayed there and then when I made it worse it just dropped the shutter speed more and more but still never blinked red.
Changing the ISO or allowing it to change does not change the meter sensitivity nor the amount of light hitting the sensor. As for providing a reference, I am giving the benefit of almost 50 years working with TTL metered SLRs. ISO is a red herring here since exposure is simply how much light the film or sensor is exposed to. It has two components...how big an aperture and for how long.

You can test this out. Set fixed ISO at 100 and the exposure system to Av at lens maximum aperture. In live view, point the camera to incrementally darker subjects (ideally a subject of uniform brightness) until you get red blinkies for shutter, aperture, and ISO (all three at once). Look up the combination of shutter speed and aperture on the table in the EV article in the Wikipedia to get the lower limit of the live view meter expressed as EV100. LINK This test satisfies the first case. If all three blink, it is an issue of meter sensitivity/linearity.*

Now, leaving the aperture at maximum aperture, find a subject dim enough at ISO 100 to return a shutter speed of 4 seconds. Keeping the subject in the frame, close down the aperture until you get blinkies for the shutter setting only. The setting should read 30" and the actual metered EV would be at least one stop longer shutter speed if the camera supported such in Av mode. If this were a K1000 film camera, the dial would simply go no further, despite the meter quite happy. Do the same in Tv mode. If only one setting blinks, the required exposure in that mode is beyond the settings available for the camera as configured for the lens mounted.

Steve

* Back in the old days, Pentax included a table showing the ranges of shutter/aperture combinations that were within the meter's linear range. For example, the table on page 23 in the KX (film) manual indicates that a combination of f/22 at 1/1000s for ISO 100 is beyond the linear range of the SPD meter at the high end. The meter is only linear from EV 1 to EV 18. For the KM (film) with its CdS meter, the range is somewhat more limited with the low end effected as well. The Pentax CdS meters are only linear from EV 3 to EV 18.
06-25-2019, 12:29 AM - 2 Likes   #18
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QuoteOriginally posted by stevebrot Quote
Changing the ISO or allowing it to change does not change the meter sensitivity nor the amount of light hitting the sensor. As for providing a reference, I am giving the benefit of almost 50 years working with TTL metered SLRs. ISO is a red herring here since exposure is simply how much light the film or sensor is exposed to. It has two components...how big an aperture and for how long.

You can test this out. Set fixed ISO at 100 and the exposure system to Av at lens maximum aperture. In live view, point the camera to incrementally darker subjects (ideally a subject of uniform brightness) until you get red blinkies for shutter, aperture, and ISO (all three at once). Look up the combination of shutter speed and aperture on the table in the EV article in the Wikipedia to get the lower limit of the live view meter expressed as EV100. LINK This test satisfies the first case. If all three blink, it is an issue of meter sensitivity/linearity.*

Now, leaving the aperture at maximum aperture, find a subject dim enough at ISO 100 to return a shutter speed of 4 seconds. Keeping the subject in the frame, close down the aperture until you get blinkies for the shutter setting only. The setting should read 30" and the actual metered EV would be at least one stop longer shutter speed if the camera supported such in Av mode. If this were a K1000 film camera, the dial would simply go no further, despite the meter quite happy. Do the same in Tv mode. If only one setting blinks, the required exposure in that mode is beyond the settings available for the camera as configured for the lens mounted.

Steve

* Back in the old days, Pentax included a table showing the ranges of shutter/aperture combinations that were within the meter's linear range. For example, the table on page 23 in the KX (film) manual indicates that a combination of f/22 at 1/1000s for ISO 100 is beyond the linear range of the SPD meter at the high end. The meter is only linear from EV 1 to EV 18. For the KM (film) with its CdS meter, the range is somewhat more limited with the low end effected as well. The Pentax CdS meters are only linear from EV 3 to EV 18.
Yep thanks Steve, sorry you had to write all that down, I discovered early today that one exposure parameter blinking was user error, all three was AE metering struggling. And I didn't mean to be weird, like 'back up what yer saying', I kinda meant it in terms of whether anything like a sidenote about this was in a manual (as I'm talking about this on FB Pentax groups and it would just be easier to screen grab a blurb from the manual or something to put the conversation to an end/conclusion.
06-25-2019, 04:57 AM   #19
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QuoteOriginally posted by BruceBanner Quote
It's just not what my experience of Av mode does is all. You said;

"When I set my KP to Av mode, it keeps ISO at 100 and continually lowers shutter speed; when using LV and shutter speed gets down to 8" the three exposure parameters start flashing red"

Normally when my shutter speeds get down to around 1/50 or 1/25 (depending on lens attached), it halts and doesn't drop any lower, now what happens is the shutter speed stays fixed (for awhile) and the ISO starts to raise. Once my settings shift from say 1/25 ISO 100 to being 1/25 ISO 3200 (my self imposed Auto ISO limit) it would then drop the shutter speeds further down and keep the ISO still at 3200. All of this purposeful and how I want that mode to work for me.
After a good night's sleep, I have decided to limit my response - the untimely death of @CWRailwayman (*) reminds me of the futility of what I call "recreational arguing". We have now established
1. my methods are different than yours
2. my KP is set up differently than yours
3. to answer your original question, nothing is wrong with your KP
4. neither of us is likely to function in the "Red Zone" often, and we know we have to use manual methods when there


(*) In my early days here, when he had many times more posts here than I did, he tried to convince me that my fears of an EVF-less "Q" were unfounded. I knew from earlier experience that his methods wouldn't work for me, but I purchased a Q-7 anyway, and did find ways of making it useful for me.

06-25-2019, 06:48 AM   #20
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QuoteOriginally posted by BruceBanner Quote
I kinda meant it in terms of whether anything like a sidenote about this was in a manual
Ha! Ha! That would have been nice, but I could not find an outside reference and had to write down how I figured out what was going on back a few years ago when I first saw the blinkies on my K-3.


Steve
06-25-2019, 08:28 AM   #21
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QuoteOriginally posted by stevebrot Quote
Ha! Ha! That would have been nice, but I could not find an outside reference and had to write down how I figured out what was going on back a few years ago when I first saw the blinkies on my K-3.


Steve
From my simple minded analysis of the LV red blinking test, the camera might be telling something as simple as you need to engage your flash. I just tried all of this on my K-3 and got red blinking in LV but when using the viewfinder my flash symbol was blinking. If you look at the LV histogram its slammed up against the left side so obviously you need to do something to change the amount of light available and the camera is advising you of that. I realize that metering is different in LV than through the viewfinder

As soon as the left edge of the histogram leaves the left side the red blinkies turn off.

Last edited by Larrymc; 06-25-2019 at 08:40 AM.
06-25-2019, 01:41 PM   #22
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Larrymc, if it was saying use flash why would a f/5 say at 1/4 shutter and f/11 say 1". That explanation doesn't account for that. Light meter having problems does.
06-25-2019, 02:07 PM   #23
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QuoteOriginally posted by reh321 Quote
After a good night's sleep, I have decided to limit my response - the untimely death of @CWRailwayman (*) reminds me of the futility of what I call "recreational arguing". We have now established
1. my methods are different than yours
2. my KP is set up differently than yours
3. to answer your original question, nothing is wrong with your KP
4. neither of us is likely to function in the "Red Zone" often, and we know we have to use manual methods when there


(*) In my early days here, when he had many times more posts here than I did, he tried to convince me that my fears of an EVF-less "Q" were unfounded. I knew from earlier experience that his methods wouldn't work for me, but I purchased a Q-7 anyway, and did find ways of making it useful for me.
I didn't think we were 'recreationally arguing'

QuoteOriginally posted by stevebrot Quote
Ha! Ha! That would have been nice, but I could not find an outside reference and had to write down how I figured out what was going on back a few years ago when I first saw the blinkies on my K-3.


Steve
QuoteOriginally posted by Larrymc Quote
From my simple minded analysis of the LV red blinking test, the camera might be telling something as simple as you need to engage your flash. I just tried all of this on my K-3 and got red blinking in LV but when using the viewfinder my flash symbol was blinking. If you look at the LV histogram its slammed up against the left side so obviously you need to do something to change the amount of light available and the camera is advising you of that. I realize that metering is different in LV than through the viewfinder

As soon as the left edge of the histogram leaves the left side the red blinkies turn off.
QuoteOriginally posted by swanlefitte Quote
Larrymc, if it was saying use flash why would a f/5 say at 1/4 shutter and f/11 say 1". That explanation doesn't account for that. Light meter having problems does.
I think if the camera was hinting at flash needing used then it should maybe just blink that symbol or something. I dunno... after using the K-1 for so long and not seeing any text turn red and blinking at me... I kinda prefer that to the ever so slightly (but perhaps helpful) red blinking text across the screen. I think it's added to unnecessary confusion because many of us (myself definitely included) were associating red blinking text with an exposure issue caused my user. They had lots of options here to differentiate more easily, white blinking text for example, or yellow blinking text, or perhaps red but not blinking... but they chose the same thing and hence added confusion.

06-25-2019, 02:46 PM   #24
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QuoteOriginally posted by BruceBanner Quote
I didn't think we were 'recreationally arguing'
but continuing the discussion would be. I have told you about my experience .... you can make use of it or you can ignore it .... I have nothing more to say.
06-25-2019, 03:28 PM   #25
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QuoteOriginally posted by reh321 Quote
but continuing the discussion would be. I have told you about my experience .... you can make use of it or you can ignore it .... I have nothing more to say.
I'm detecting a little animosity here.

Your first comment in this thread had nothing to do with the blinking red text issue, but rather a statement about my ISO 3200 being conservative. It's presumptuous at best. I have various Av modes set up on my gear, what ISO I set myself at depends largely on what I shoot and whether I feel as though I can manage a drop of shutter speed in an effort to keep my ISO under control. Shooting an adult standing still at an event (which is what my paid income is for) I find 3200 the highest I want to go to, adults can stay fairly still for a shot, and if flash is used (and often is) and I mix ambient and flash together, then I find anything above 3200 ISO is degrading picture quality unnecessarily. Other Av modes and I have my ISO set higher, kids, concerts, whatever, it all depends. But none of this was even relevant to the red blinking text issue.

You then stated you changed your ISO parameters to being being 100-3200, but then you claim that it kept ISO at 100 and dropped down to 8 secs, and it was at this point that you encountered the blinking. My only point was that your ISO must have been fixed at 100 and not Autoing between 100-3200 because that behaviour is in line with what I have seen to be true in Av mode. If you were in Auto-ISO it would have maxed out at 3200 ISO and then lowered shutter speeds. I just cannot understand how you can have such a long shutter exposure (8 secs) and still have ISO at 100 unless you fixed it (albeit accidentally) in Av mode. But never did I call you a liar, or wrong, I'm simply asking if that may have been the case, and if not can you replicate that so that I can learn some more.

Furthermore, your assessment that the red blinking is correlated to the idea that they are warning you that you are below reasonable hand-held levels seems to be untrue.

All in all, I have found your advice not helpful, misinformed and wrong (unless of course you can show with greater evidence your stance is correct).

I don't know why people have such a hard time in saying "Woops... got that wrong... I see now how things are working." People that know me here know I admit I am wrong and am thankful for being educated correctly all the time. I don't like to presume that others are wrong and so give them a chance to properly explain and submit examples or screen grabs/videos or siting a reference etc etc.

So I'm sorry we got off on the wrong foot, I am sorry if you have taken anything I have said the wrong way, I am going to apologise right now and here if I have somehow inadvertently offended you, that was never my intention. I'm sorry.
06-25-2019, 03:36 PM - 3 Likes   #26
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Ah, the joys of communicating via internet forums instead of face-to-face... Let's take a breath and keep this friendly Thank you
06-25-2019, 05:06 PM   #27
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QuoteOriginally posted by BruceBanner Quote
I think if the camera was hinting at flash needing used then it should maybe just blink that symbol or something. I dunno... after using the K-1 for so long and not seeing any text turn red and blinking at me... I kinda prefer that to the ever so slightly (but perhaps helpful) red blinking text across the screen. I think it's added to unnecessary confusion because many of us (myself definitely included) were associating red blinking text with an exposure issue caused my user. They had lots of options here to differentiate more easily, white blinking text for example, or yellow blinking text, or perhaps red but not blinking... but they chose the same thing and hence added confusion.
In live view there is no flash symbol as there are in the "automatic" modes Green, P, Tv and Av when using the viewfinder and it will blink signalling the operator to activate the flash so my conclusion is the system is signalling to the operator that there is not enough light to reasonably take the shot or possibly that there is not enough light to achieve focus. Thus my conclusion. I guess my "WAG" is as good as anyother.
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