[BruceBanner]

Ah, I misinterpreted your 400 as a max rather than as a min, apologies. All I’m saying is that I don’t over-focus (sorry for the pun) on ISO, as it’s so comparatively good in today’s digital cameras - back in my film days, I used to agonise about pushing an ISO200 film to ISO400 for an entire roll. So I don’t chase ISO100, and with that as the lower end of the auto-ISO range don’t have an issue since if the camera needs to, it’ll lift it anyway to whatever the acceptable maximum is, given post-processing. And then if need be, thanks to the flexibility of hyper-P, if I need a minimum shutter speed, I can flip to Tv instantly.

Ah yes, but when, how and at what cost? If you're happy to kill ISO values 100-400 and have every shot taken at ISO 800 minimum, you get greater variables to play with, such as more room to move with stopping down on Aperture or Shutter Speeds, even in 'Auto ISO setting' modes.

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Last edited by BruceBanner; 05-28-2018 at 05:23 PM.

[microlight]

The cost entirely depends on the subject and conditions, and the trade-offs you make in order to get a shot you might otherwise not get. A peaceful landscape requires a different approach to a semi-dark club acoustic performance, for example. Do I use the long end of my zoom at 40mm/f2.8, or strap on a 50mm/f1.4 to give me two extra stops of ISO? Even though DR will suffer the higher you go as others have noted, it’s maximised by what our cameras give us in RAW files, and by what can be pulled out in PP. If I can get a static picture at ISO1600 whereas I’d get motion blur at ISO200, I’d go for the static image every time, and deal with noise later if necessary - or as Norm says, it might actually assist in the mood. As such, I don’t see the value in purposely setting the ISO minimum at 800, there are other ways to skin that particular feline, like the hyper-P method above. That’s not to say that your rationale wouldn’t work - go with it and see if it gives you what you’re looking for. By posting, you were asking for opinions, and that’s what you’re getting!

All in the best possible taste, of course!

[photoptimist]

...

So do I lol, I would never have my Auto ISO between 100-400 hehe
I'm talking about having it set at 400-6400 or 800-6400, thus allowing greater choice for shutter speeds and aperture choices (and hopefully more keepers).




Not disagreeing with any of that, I think you're perhaps not quite fully understanding my point. I'm talking about ditching ISO of 100, 200 and instead setting the lower limits to 400 or 800 because by having the lower limit at that level gives more control over the other exposure controls. Basically the K-1 (and KP) are so good at controlling noise that ISO 100-200 are essentially overkill (in certain scenarios). Scenarios whereby shutter speed or narrow apertures matter more than keeping the ISO to 100, 200 or even 400!
It goes without saying when doing landscape work and other shots where you're pixelshifting or seeking the highest quality, ISO 100 is needed (as well as likely tripod). Don't get me wrong, if possible I would always love to have an ISO 100 image, right now though I'm questioning my settings for those impromptu shots whereby perhaps I have missed a few nice candid moments because I chose to keep things at prioritising ISO 100, or felt I couldn't narrow the DoF due to increase noise creeping in etc.

Locking the ISO to 800-6400 creates a NARROWER choice for shutter speeds and aperture choices than does a wide ISO range such as 100-6400.

With a min ISO of 800, you'll be prevented from opening the aperture wider than f/5.6 in sunny situations. And at ISO 800 you can't select a slow shutter speed if you want some motion blur (e.g., falling autumn leaves). You lose 3-stops of choice by restricting the ISO to 800.

There's no reason to prioritize ISO 100 but there's also no reason to avoid 100 ISO.

[DeadJohn]

I agree that ISO 800 is good with the current sensors in Pentax cameras. Noise is well controlled. There's no reason to be afraid of ISO 800 and higher if that's what's needed. IMO the sample photo is a good portrait, but not a good test of noise performance because B&W hides a lot of noise as ISO climbs.


There are multiple approaches to the same problem of getting a fast enough shutter in dim light. I'll often underexpose with one stop lower ISO and adjust in Lightroom - I feel this offers improved dynamic range and never blows highlights.


In good light, typically outdoors, there's no reason not to use ISO 100 for action. A good action shot at ISO 800 might become an even better shot at ISO 400 or lower when there's enough light to maintain acceptably fast shutter speeds.


TAv is a great mode for action. Set your shutter speed (fast to freeze action, slower if you want motion blur*) and aperture (stop down for sharpness or extra depth of field, wide open if low light or you want thin depth of field), then let the camera dynamically adjust ISO for exposure. Be wary of overexposure in bright light - if I pick a slow shutter and wide aperture then the ISO pins itself at 100 and can't go any lower - it's easily managed if I periodically glance at the selected ISO and speed up the shutter when the camera consistently picks ISO 200 or lower.


(*) As an example of desirable blur, it's often for propeller aircraft and helis. Too fast of a shutter freezes the blades and looks bad IMO.

[BruceBanner]

The cost entirely depends on the subject and conditions, and the trade-offs you make in order to get a shot you might otherwise not get. A peaceful landscape requires a different approach to a semi-dark club acoustic performance, for example. Do I use the long end of my zoom at 40mm/f2.8, or strap on a 50mm/f1.4 to give me two extra stops of ISO? Even though DR will suffer the higher you go as others have noted, it’s maximised by what our cameras give us in RAW files, and by what can be pulled out in PP. If I can get a static picture at ISO1600 whereas I’d get motion blur at ISO200, I’d go for the static image every time, and deal with noise later if necessary - or as Norm says, it might actually assist in the mood. As such, I don’t see the value in purposely setting the ISO minimum at 800, there are other ways to skin that particular feline, like the hyper-P method above. That’s not to say that your rationale wouldn’t work - go with it and see if it gives you what you’re looking for. By posting, you were asking for opinions, and that’s what you’re getting!

All in the best possible taste, of course!

Which is why I was trying to explain the 'scenario' for where this discussion takes place, impromptu/action/quick candid moments, not landscape stuff.

The point of this thread is not to point out that we all would rather have a static higher noise image rather than a lower noise but blurred/ruined shot, the point is how do we make our equipment give us a higher percentage chance of getting those more difficult candid/impromptu shots (can changing the MIN ISO level amount be a clever method)? If you read on below I will explain more from where this question and point I am making which prompted this thread.

Locking the ISO to 800-6400 creates a NARROWER choice for shutter speeds and aperture choices than does a wide ISO range such as 100-6400.

With a min ISO of 800, you'll be prevented from opening the aperture wider than f/5.6 in sunny situations. And at ISO 800 you can't select a slow shutter speed if you want some motion blur (e.g., falling autumn leaves). You lose 3-stops of choice by restricting the ISO to 800.

There's no reason to prioritize ISO 100 but there's also no reason to avoid 100 ISO.

Ok, I shall try to explain what I have been seeing and experiencing with my Av mode by quickly demonstrating what is happening in my home as I point my camera towards a fixed point (it's tripodded);

A) I'm in Av mode, Auto ISO Setting 100-3200, Parameters set to Slow. In this mode and settings I am given the following = 1/50, f3.2, ISO 100

B) With the camera facing the exact same location I now simply make one small change to the settings, I raise the min Auto ISO Setting to 800 (800-3200 instead of 100-3200), I now get the following reading = 1/160, f3.2, ISO 800

C) One more time, this time I set the min Auto ISO Setting to 400 (400-3200 now), I now get the following = 1/80th, f3.2 ISO 400

The entire point to my thread is that currently I have been in using A) settings i.e. 100-3200, and in certain lighting conditions and impromptu situations I have fired off a shot and it's been clean but blurry due to the 1/50th shutter speed and an ISO of 100 etc. By simply stating to the device that I am happy to walk away with an image containing 400 or 800 ISO I am graced with faster and safer shutter speeds, and that is my entire point. I don't think my eye can really tell a huge difference between ISO 100-200 and the same between 200-400, I can probably see a difference between 100-400, and definitely between 100-800. It's funny to me because this topic starts to mirror my previous fascination with Audio (my previous 'obsession'), whereby I would do such things as ABX testing and determined upon repeat testing my ears could not tell the difference between a 320kbps MP3 file vs a 16 bit FLAC file, heck I even found it hard to hear a difference between 192kbps MP3 and 16 bit lossless FLAC, but there's a point where you can tell the difference, 128kbps MP3 files (and 160kbps) were noticeably worse in quality than compared to 320kbps, but why then do we really need FLAC if a large proportion in reality cannot hear the difference). Not meaning to steer the conversation off topic but I think you get my point, I'm pondering if having my settings seeking out 100 or 200 ISO has harmed my success rate when capturing certain candid moments (arguably the best moments!) when having it at 400 would give me more 'comfort'.

I navigated around this issue by changing the Auto ISO Parameters from Slow to Normal or Fast (assigned them as different User Modes), that way I could quickly change the minimum shutter speed I'd encounter at the expense of bringing more noise into the image, and maybe that's all I should really be doing, getting rid of Slow and Normal modes and only shoot Av mode with Fast parameters, on days I can get away with it I get ISO 100, in trickier lighting settings I at least get no motion blur but a noisier image I can live with...
Or perhaps leave it at Normal and have Auto ISO set between 400-3200, because I can't tell a huge difference between 100-400 anyway, and this gives me better shutter speeds to work with.

I agree that ISO 800 is good with the current sensors in Pentax cameras. Noise is well controlled. There's no reason to be afraid of ISO 800 and higher if that's what's needed. IMO the sample photo is a good portrait, but not a good test of noise performance because B&W hides a lot of noise as ISO climbs.


There are multiple approaches to the same problem of getting a fast enough shutter in dim light. I'll often underexpose with one stop lower ISO and adjust in Lightroom - I feel this offers improved dynamic range and never blows highlights.


In good light, typically outdoors, there's no reason not to use ISO 100 for action. A good action shot at ISO 800 might become an even better shot at ISO 400 or lower when there's enough light to maintain acceptably fast shutter speeds.


TAv is a great mode for action. Set your shutter speed (fast to freeze action, slower if you want motion blur*) and aperture (stop down for sharpness or extra depth of field, wide open if low light or you want thin depth of field), then let the camera dynamically adjust ISO for exposure. Be wary of overexposure in bright light - if I pick a slow shutter and wide aperture then the ISO pins itself at 100 and can't go any lower - it's easily managed if I periodically glance at the selected ISO and speed up the shutter when the camera consistently picks ISO 200 or lower.


(*) As an example of desirable blur, it's often for propeller aircraft and helis. Too fast of a shutter freezes the blades and looks bad IMO.

Before using Av mode a lot, I was a TAv junkie, so I really understand where you're coming from, however there were moments I would move from very light to very dark environments, the shutter speed and ISO would blink and I'd have a few moments to get my head together and get a better choice of settings for that new environment I walked into, this then meant I often missed a nice moment, too much fiddling.
With Av Mode, I had to only control one exposure control (aperture), I could navigate from light to dark environments and often not need to change a single thing, I could stipulate a shutter speed that I didn't want the Av mode to ever dip below, and just let the ISO fall where it may.

Perhaps a Tv mode might make more sense for the kind of scenario I am proposing. It's a mode I rarely use, but having a quick look right now, I could pretend I am in a impromptu setting, quickly adjust the shutter speed to 1/125, but it's only raising the aperture once it gets to ISO 100, if higher ISO is needed such as 200-800 it keeps the aperture wide open (too wide for some lenses like my FA50mm1.4).

[leekil]

You can change the program line (to "action") to prioritize faster shutter speeds, and that might do what you want but still allow you to use a 100-3200 ISO setting.

Or, use the TAv mode, and fix your shutter speed and aperture and let the ISO change through the 100-3200 range.

You could also use the DA 55, which seems to specially prioritize thin DOF, so it would therefore always kind of favor faster shutter speeds.

[MrB1]

Not negating the thread point but, for the same scene, A:1/50, f/3.2, ISO 100, and B: 1/160, f/3.2, ISO 800, the readings are not equivalent.

[BruceBanner]

You can change the program line (to "action") to prioritize faster shutter speeds, and that might do what you want but still allow you to use a 100-3200 ISO setting.

Or, use the TAv mode, and fix your shutter speed and aperture and let the ISO change through the 100-3200 range.

You could also use the DA 55, which seems to specially prioritize thin DOF, so it would therefore always kind of favor faster shutter speeds.

I'm not finding any difference (with exposure values) when in Av mode and choosing between Action or DoF under the Program Line. My understanding that the Program Line was more for when in Manual Mode and pressing the Green button, but we're not really doing that in Av mode?

TAv mode is an option yes, but a little more fiddly with more things to keep an eye on (as I said before).

[microlight]

I know exactly what you mean about the analogy with low bitrate mp3/FLAC (I went through the same thing), and I think that a similar philosophy works in photography. In other words, in the same way that having the maximum audio information available gives ‘space’ around the sound, rather than being ‘boxier’ and yes, compressed (even if the actual improvement is hard to put your finger - or eardrum - on), taking a RAW photo with a maximum defined sensitivity range enabled gives the IQ of being the best it can be in the circumstances under which the photo is taken. This is also why I use hyper-P, because as well as using an ISO range typically between 100 and 3200 (or 6400 depending on circumstance), I can switch between Av and Tv without taking my eye away from the viewfinder, and I’d really recommend that you give it a try.

Low ISO is only one part of a complex photographic equation that you rationalise on the fly, and yes, maybe over-focusing (sorry about the pun again) on achieving low ISO is diverting your real-time processing from from getting shots that you think you should have got. Additional tweaks such as setting the ISO speed change parameter or using the action program lines aren’t work-arounds; they’re there to modify the settings more to your liking.

Our cameras give us a huge - often bewilderingly huge - choice of settings and modes, so trying to keep it all simple can be increasingly difficult. Maybe another option for getting candid moments could be to switch out of auto-ISO mode altogether at times when you’re looking for this type of photo, and set a fixed ISO of say 800 or 1600 which would take away the variable of worrying about which auto-ISO range to set. (There are those here that wouldn’t touch auto-ISO with the proverbial barge-pole in any case!)

Lots of options in this thread, Bruce; hope you find one that works for you.

[BruceBanner]

I know exactly what you mean about the analogy with low bitrate mp3/FLAC (I went through the same thing), and I think that a similar philosophy works in photography. In other words, in the same way that having the maximum audio information available gives ‘space’ around the sound, rather than being ‘boxier’ and yes, compressed (even if the actual improvement is hard to put your finger - or eardrum - on), taking a RAW photo with a maximum defined sensitivity range enabled gives the IQ of being the best it can be in the circumstances under which the photo is taken. This is also why I use hyper-P, because as well as using an ISO range typically between 100 and 3200 (or 6400 depending on circumstance), I can switch between Av and Tv without taking my eye away from the viewfinder, and I’d really recommend that you give it a try.

Low ISO is only one part of a complex photographic equation that you rationalise on the fly, and yes, maybe over-focusing (sorry about the pun again) on achieving low ISO is diverting your real-time processing from from getting shots that you think you should have got. Additional tweaks such as setting the ISO speed change parameter or using the action program lines aren’t work-arounds; they’re there to modify the settings more to your liking.

Our cameras give us a huge - often bewilderingly huge - choice of settings and modes, so trying to keep it all simple can be increasingly difficult. Maybe another option for getting candid moments could be to switch out of auto-ISO mode altogether at times when you’re looking for this type of photo, and set a fixed ISO of say 800 or 1600 which would take away the variable of worrying about which auto-ISO range to set. (There are those here that wouldn’t touch auto-ISO with the proverbial barge-pole in any case!)

Lots of options in this thread, Bruce; hope you find one that works for you.

Glad to hear someone get the audio reference (I was worried it would be lost...)

I did try Program Mode (Hyper) for a few months, I found myself not using it a whole lot but I might go back to it, force myself to shoot with it for awhile because as you say, having the ability to toggle between Av and Tv without taking the eye away from the viewfinder was very useful.
IIRC what stumped me about that mode was again the kinda prioritising of the way Auto ISO would work. Example;

I'm in Hyper Av, i have f3.2 but noticed the shutter speed is gonna me too low, so i increase the shutter speed (now in Hyper Tv mode), but noticed the aperture dropped immediately to f1.4 just so AUTO Iso would stick to being 100 etc.

I think it might be about tinkering and getting that Hyper-P to play ball better, either by having a higher MIN Auto ISO level (such as 200 or 400) it might just give me that extra room I need. Or mess around with 'Fast' and 'Action' etc.

I wish to point out, its not that I strive for every shot to shoot at 100 ISO, it's just I have been selecting Auto ISO for a long time now, and the parameters being 100-3200 (or 6400 as you say on those tough lighting moments). It seems that the things I care about (shutter speed and aperture) suffer more than the camera just bumping the ISO up a notch, and it's how to control that aspect I'm trying to nail down.

[BarryE]

Our modern cameras do make us suffer, don't they ;-)

When a question is raised or advice requested, out comes a torrent of well meaning advice. I've tried to keep up with this thread, but somewhere through it I rather lost it. Not especially because of the complexity of the OP's question/request, more because I again felt that with so many options, I kept on reminding myself that at the heart of this thread is the basic shutter speed/aperture/ISO decision that the photographer - not the camera - needs to make. It's always been the same. Little has changed, just the convenience of PP to recover/enhance a less than perfect image, and the latitude we enjoy with digital.

Also, a critical piece of advice that is so often lost is, "what is the intended output". Screen ? Print ? Size ? Without knowing how an image is going to be used, it's always going to be a gamble. Photography is 'easy' in the Instagram/small screen world, when an image can be cropped and PPed massively, then any decision on ISO etc is mostly irrelevant. But, to capture a shot that a photo editor, stock supplier (not newsfeed), fine-art/gallery owner etc., requires is rarely unplanned.

The analogy with audio is clearly a good one. A music producer typically makes a recording at the best quality to capture all the data available. Why would they do anything else ? The user then picks how they want to consume the recording.

Each of us will have an approach to taking photos. When taking snap-shots for social media, friends & family, who really cares what the settings are provided they are close enough - the composition is probably more important. However, for non-snap-shots, like a record producer, I try (and mostly fail) to capture the maximum data data I can, coz I never really know how a successful image might be consumed. This inevitably means as low an ISO as I can manage, provided the other two sides of the Exposure Triangle are fully considered. The camera can't really do this as it can't read minds ...

This post will probably fall on barren ground, as I'm probably out of sync (again) with most folk here who tend to be more automated than me.

[BruceBanner]

Our modern cameras do make us suffer, don't they ;-)

When a question is raised or advice requested, out comes a torrent of well meaning advice. I've tried to keep up with this thread, but somewhere through it I rather lost it. Not especially because of the complexity of the OP's question/request, more because I again felt that with so many options, I kept on reminding myself that at the heart of this thread is the basic shutter speed/aperture/ISO decision that the photographer - not the camera - needs to make. It's always been the same. Little has changed, just the convenience of PP to recover/enhance a less than perfect image, and the latitude we enjoy with digital.

Also, a critical piece of advice that is so often lost is, "what is the intended output". Screen ? Print ? Size ? Without knowing how an image is going to be used, it's always going to be a gamble. Photography is 'easy' in the Instagram/small screen world, when an image can be cropped and PPed massively, then any decision on ISO etc is mostly irrelevant. But, to capture a shot that a photo editor, stock supplier (not newsfeed), fine-art/gallery owner etc., requires is rarely unplanned.

The analogy with audio is clearly a good one. A music producer typically makes a recording at the best quality to capture all the data available. Why would they do anything else ? The user then picks how they want to consume the recording.

Each of us will have an approach to taking photos. When taking snap-shots for social media, friends & family, who really cares what the settings are provided they are close enough - the composition is probably more important. However, for non-snap-shots, like a record producer, I try (and mostly fail) to capture the maximum data data I can, coz I never really know how a successful image might be consumed. This inevitably means as low an ISO as I can manage, provided the other two sides of the Exposure Triangle are fully considered. The camera can't really do this as it can't read minds ...

This post will probably fall on barren ground, as I'm probably out of sync (again) with most folk here who tend to be more automated than me.

Hey Barry, thanks for the response, some great points here.

I tend to use flickr, I used to allow downloading and viewing of my images in its original file size, I put a stop to that recently (only friends and families get that privilege). There are plenty of images I take that I feel aren't up to scratch for me to display on Flickr but I am quite happy to bump the image to Instagram, usually it's not ISO or noise that impacts this decision but rather sharpness of lack thereof. So yeah I fully understand the 'format' point you're bringing up.

My approach to taking photos of course changes from what I'm snapping to what I want to achieve. Landscape typically means Manual mode, People typically means Av mode. Av Mode lets me concentrate fully on composition/framing and the depth of the image, I then cross my fingers a little as to what the shutter speed and ISO report back. (Occasionally I get situations that allow me to chimp, when I get the chance to do that I then also use the EV +/- button for exposure compensation and shoot again). For the most part it gets it right, but my aforementioned example is where it gets it wrong, I'll repeat this part if you missed it;

"Ok, I shall try to explain what I have been seeing and experiencing with my Av mode by quickly demonstrating what is happening in my home as I point my camera towards a fixed point (it's tripodded);

A) I'm in Av mode, Auto ISO Setting 100-3200, Parameters set to Slow. In this mode and settings I am given the following = 1/50, f3.2, ISO 100

B) With the camera facing the exact same location I now simply make one small change to the settings, I raise the min Auto ISO Setting to 800 (800-3200 instead of 100-3200), I now get the following reading = 1/160, f3.2, ISO 800

C) One more time, this time I set the min Auto ISO Setting to 400 (400-3200 now), I now get the following = 1/80th, f3.2 ISO 400"

I believe I have been faced with too many situations where A occurred, it's all my own fault, I shouldn't have had 'Slow' set as the ISO Auto Parameters, had I had it at Normal or Fast I would have had faster shutter speeds albeit with more noise.
Or I could decide to stuff ISO 100 and just set 400 as my minimum, but then as you say there are benefits to low ISO in terms of print and also exposure in other circumstances (I might need ISO 100 for very bright sunny days and shooting f1.4-1.6!).

And you're right, the camera can't always know or read minds, but the options it has can help steer it more towards our scenarios and lighting conditions.
Right now I am exploring ways to try and ensure that scenario 'A' doesn't occur. It could be that I switch to 'Fast' for Auto ISO Parameters and never look back and that provides the fix. Or... have an Av mode set up but fix the ISO or have that Auto ISO range a little more restrictive (400-3200), call it 'indoor' Av mode etc.

"There's more than one way to skin a cat!" is the correct saying for this scenario I think

[leekil]

I'm not finding any difference (with exposure values) when in Av mode and choosing between Action or DoF under the Program Line. My understanding that the Program Line was more for when in Manual Mode and pressing the Green button, but we're not really doing that in Av mode?

TAv mode is an option yes, but a little more fiddly with more things to keep an eye on (as I said before).

The way the settings seem to work, based on some screwing around with them on a K-3 II just now, is that when you set the Auto ISO to Fast or Slow, it tends to change the priority of switching the ISO. If you have it set to Fast, it will be more likely to change the ISO to achieve the correct exposure and then start to change the shutter speed (in Av mode). Similarly, if it is set to Slow, it will change the shutter speed before it will change the ISO.

The Action mode does seem to prioritize the shutter speed; it does not totally maximize the shutter speed, but it will tend toward a reasonably high minimum shutter speed while adjusting the other non-fixed parameters moderately.

Note that the Aperture/shutter speed are constrained more by using Av mode. In P mode, the aperture will also change, helping to achieve the same results as described above, but with more flexibility. The shutter speeds will generally be higher in Action mode, as the aperture will be able to opened wider if it is not constrained. Similarly, if you use DOF mode, the shutter speed will not change as much, as it will try to use a smaller aperture. Again, it doesn't totally minimize the aperture, but it tries to use a smaller one, but also still balancing the other parameters that you have allowed it to set, to use reasonable values of them.

[MrB1]

Not negating the thread point but, for the same scene, A:1/50, f/3.2, ISO 100, and B: 1/160, f/3.2, ISO 800, the readings are not equivalent.

As these odd sets of readings have been quoted again - changing ISO 100 to ISO 800 is 3 stops so, for the same scene, one would expect the shutter speed to have increased by three stops, i.e. from 1/50s to 1/400s. Perhaps a typing error somewhere?

[sculptor666]

if you nail everything just right, iso 800 can be near iso 100 quality on the k-1... but if you don't nail everything, iso 100 gives is more forgiving in post.