[BruceBanner]

Ok, so I'm not sure where to put this subject matter in terms of category so I've chosen 'Action' as in terms of difficult, quick or impromptu shooting rather than any other scenario.
On the weekend I took an image at ISO 800 that I felt was very sharp and clean, please see below;



I was in Av mode, and this was a total impromptu shot, the f5 aperture was left over from shooting someone else in a different location/scene, but you can see I had a shutter speed of just 1/40th, and with kids that's dangerously low, basically I got lucky here.

But it made me think... I was really impressed with the image quality at ISO 800, am I 'damaging' my potential success shot rate by insisting on getting those images captured at the 100-400 ISO level, when really ISO 400-1600 is perfectly acceptable? I think I have been put off with 1600-3200 ISO in the past as that's usually what I get when shooting concerts and public speakers, but I feel as though the noise of ISO changes its impact depending upon what is being photographed (such as closeness of the subject etc, further away the grain/noise feels more pronounced, closer in (like above) and it comes off as almost completely clean).

I have been exploring Av Mode recently. Currently I have it bound to 3 User Modes, each mode is the exact same settings wise except in the Menu 1>ISO Auto Setting>AUTO ISO Parameters is set to Slow (User Mode 1), Normal (User Mode 2) or Fast (User Mode 3). If you're unaware of what this does, it changes the minimum shutter speed encountered before bumping up the ISO, the shutter speed only drops further if/when encountering the need for correct exposure past the (Maximum) ISO Range set.
So if the subject is relatively still (or posing), I have been tending to use User Mode 1 (Av) and AUTO ISO set to Slow, if the subjects are little people that fidget and move a lot more then I toggle to User Mode 3 (av) where AUTO ISO Parameters are set to Fast.

Example;

K-1+DFA 100, ISO Parameter Slow = 1/60th shutter speed. If I set my Max ISO to 3200 then once it hits that limit the shutter speed will drop below 1/60. When ISO Parameter is set to Fast shutter speed will not drop below 1/250th.

Interestingly enough the KP takes this process one step further and allows you to actually specify the exact shutter speed met, rather than with a general 'Slow', 'Normal' and 'Fast'. Neat.

So... having taken this shot on the weekend I am starting to evaluate my necessity in having those shots taken at very low ISO's such as 100 and 200 etc. I can set the Minimum ISO Range as well as Maximum. Perhaps if I chose a minimum of 400 or 800 I would obtain more shots with higher shutter speeds, rather than letting the shutter speed get down so low as to keep the ISO at 100 etc. It's kinda another way of approaching how Av mode works, Slow, Normal and Fast or just play with the Min ISO more.
I created these 3 Av User Modes with variable AUTO ISO Parameters because changing them requires a bit of menu diving which is a PIA, however I have noticed that you can press the INFO button during shooting which takes you to that handy quick selection shortcut whereby you can't have AUTO ISO Parameters for quick selection change, but you can however have ISO AUTO MIN and MAX for quick on the fly adjustment!

It wasn't my intention to always have 3 of my User Modes bound to Av mode with only a slight deviation between them, it was just a trialling process, but the idea of having one Av mode whereby you can make quick ISO AUTO MIN adjustments appears to me to be a decent streamlined compromise.

My real purpose of this thread is to see if anyone else has felt similar, that ISO 100 is unnecessarily clean for certain situations (like overkill basically) but by having it there (even in an Auto ISO situation) has harmed the outcome of certain shots because motion blur or being scared to bump the aperture up slightly (at the expense of shutter speed) ruined the shot?

Of course I understand that ISO 100 is necessary for lots of situations such as landscape work etc, pixel shift and super resolution bla bla, which is why I dumped this question/point into the 'Action' category.

Thoughts people?

Cheers,

Bruce

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Last edited by BruceBanner; 05-28-2018 at 04:49 AM.

[photoptimist]

Any limit on the exposure parameters (e.g., never using anything other than 100-400 ISO) certainly does damage the chance of success. The nice shot you showed would almost certainly have had either motion blur (from a 1/20 sec shutter time and a child) or lack adequate depth of field (from using f/3.5).

The greater the usable ISO range, the greater the opportunities to freeze motion, increase depth of field, or shoot in dim light when you need to. Just a one-stop improvement in ISO range provides the opportunity to reduce motion blur by 50% or increase depth of field by 70%.

Max ISO is a personal preference. For us old users of 1000 ASA print film, 51200 ISO on the K-1 ain't half bad.

[BruceBanner]

Any limit on the exposure parameters (e.g., never using anything other than 100-400 ISO) certainly does damage the chance of success. The nice shot you showed would almost certainly have had either motion blur (from a 1/20 sec shutter time and a child) or lack adequate depth of field (from using f/3.5).

The greater the usable ISO range, the greater the opportunities to freeze motion, increase depth of field, or shoot in dim light when you need to. Just a one-stop improvement in ISO range provides the opportunity to reduce motion blur by 50% or increase depth of field by 70%.

Max ISO is a personal preference. For us old users of 1000 ASA print film, 51200 ISO on the K-1 ain't half bad.

So I'm coming at things from the other perspective, actually limiting the MIN ISO, setting it to something like 400 or 800 as it's MIN (and max ISO something like 3200 or 6400 etc). Basically might I get a higher success of shots/moments in those impromptu 'action' situations rather than letting the shutter speed get too low at the cost of keeping the ISO down at 100-400.
It's another experiment I think I shall embark on, shooting with my ISO no lower than 400-800 etc.

[aaacb]

Most pictures with people that I take with my digital camera (k3ii) end up in pp at iso 800+: concerts, sometimes sports, or out in the city. So every now and then when I have someone pose for a portrait, I'm amazed just how clean everything is.

But between (unintentional) motion blur and a little noise, I will always choose noise. It limits how large I can print (I should print more) or zoom into my images, but at least there's some smaller size where things look as I intended. Of course, minimal motion blur is also hidden by smaller prints, but for 2-3 stops under and with moving people that motion blur is not going to be minimal.

[BruceBanner]

Most pictures with people that I take with my digital camera (k3ii) end up in pp at iso 800+: concerts, sometimes sports, or out in the city. So every now and then when I have someone pose for a portrait, I'm amazed just how clean everything is.

But between (unintentional) motion blur and a little noise, I will always choose noise. It limits how large I can print (I should print more) or zoom into my images, but at least there's some smaller size where things look as I intended. Of course, minimal motion blur is also hidden by smaller prints, but for 2-3 stops under and with moving people that motion blur is not going to be minimal.

Have you ever purposefully set AUTO Iso and have a minimum set above 100?

[aaacb]

Have you ever purposefully set AUTO Iso and have a minimum set above 100?

Yes, when I was shooting sports outdoors during daytime for a college newspaper and I had to send jpegs sooner than I had time to process raw. I had minimum 400. I sometimes, but rarely, do this for "street" photos with zone focus because it means I don't need to worry about other settings to get small aperture and fast shutter.

[honey bo bo]

ISO 100 Too Clean?

K-3 all with built in Flash as control and or bounced slave (ceiling) See Exif for ISO Varies 800 - 3200 . I have just recently had made 12" X 16 " Canvas prints and they would go a lot bigger without any problem for Mothers Day

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Last edited by honey bo bo; 08-07-2018 at 04:31 AM.

[leekil]

I suggest you determine the highest ISO that you think is acceptable, and set your auto ISO for 100-(your top), and go from there. This has enabled you to expand your range. Then set your auto ISO program settings appropriately for the best aperture and shutter speed results with that ISO range.

For example, on the K20D, my auto ISO range was 100-1600. On the K-5, it was 100-3200, and on the K-1 100-6400. If I am in a lighting situation where those ranges are not sufficient, and I can't add more light, I will manually set it to the next ISO level up, like 12800 on the K-1 for example. But I try to avoid that.

[BruceBanner]

I suggest you determine the highest ISO that you think is acceptable, and set your auto ISO for 100-(your top), and go from there. This has enabled you to expand your range. Then set your auto ISO program settings appropriately for the best aperture and shutter speed results with that ISO range.

For example, on the K20D, my auto ISO range was 100-1600. On the K-5, it was 100-3200, and on the K-1 100-6400. If I am in a lighting situation where those ranges are not sufficient, and I can't add more light, I will manually set it to the next ISO level up, like 12800 on the K-1 for example. But I try to avoid that.

Yep that's what I'm thinking.

Currently I have been using 100-3200 for regular stuff, but in lowlight problem situations (concerts) I would go up to 6400 (and have a good minus 1.7 or more ev). What drops as I say is the shutter speed, instead of say getting the 1/60th, once it passes the max ISO it drops further, I tend to prefer that situation and spam the shutter vs going up to 12800 and staying at the 1/60th.

But yeh this is more for the 'regular' shooting conditions, I'm really wondering if I have been missing out on great deal of shots because I have been pursuing the 100 ISO too much. I think 400 ISO would be a fine starting point for the K-1, possibly 800 for the KP!

EDIT: I also noticed just now (for the first time), that if you press the Info button and navigate to ISO AUTO MIN and hit 'OK' it actually takes you to a menu whereby you can adjust both the min and max but also the Auto ISO Parameter Range as well (Slow, Normal, Fast)! That's neat!

[microlight]

Yes, I do think that restricting the range to a max of 400 limits what you can do, especially if you happen to be working with in in-camera JPG. This isn’t something I worry about as the limit is kind of artificial anyway for a RAW shooter. What do I mean? I normally use hyper-P which allows instant transition between Av and Tv, and auto-ISO with the min/max set at 100/6400 but with slow transition, so that it tries to keep the ISO as low as possible. (BTW, I have a telephoto user mode that sets Tav, such that the only variable is ISO, which if it was set at that limited range would only be useable in the brightest of light.)

What - 6400 can be acceptable from a K-3II, I hear you say in astonishment! First, I agree that a static picture with noise is better than a blurry picture with less noise. Then when shooting RAW, post-processing using a good noise reduction and sharpening technique can effectively reduce noise to a level that’s non-intrusive. So the ISO set in camera is to me less of a restriction.

[BruceBanner]

Yes, I do think that restricting the range to a max of 400 limits what you can do,

...

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).

... especially if you happen to be working with in in-camera JPG. This isn’t something I worry about as the limit is kind of artificial anyway for a RAW shooter. What do I mean? I normally use hyper-P which allows instant transition between Av and Tv, and auto-ISO with the min/max set at 100/6400 but with slow transition, so that it tries to keep the ISO as low as possible. (BTW, I have a telephoto user mode that sets Tav, such that the only variable is ISO, which if it was set at that limited range would only be useable in the brightest of light.)

What - 6400 can be acceptable from a K-3II, I hear you say in astonishment! First, I agree that a static picture with noise is better than a blurry picture with less noise. Then when shooting RAW, post-processing using a good noise reduction and sharpening technique can effectively reduce noise to a level that’s non-intrusive. So the ISO set in camera is to me less of a restriction.

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.

[BarryE]

For me I try and keep as low as possible as anything above 400 (or even 200) on K-1 and you can start to see slight differences in the tonal qualities, dynamic range and colour rendering when printing large. Yes the differences are small and yes the papers reduced gamut is important, but in test after test I can see differences, which for me can degrade the 3D quality of an image, especially when shooting into the light. If folk have never properly looked, perhaps thinking noise issues only, then maybe a close look may show up differences that they'd prefer not to bake into your images. **Obviously, ISO needs to be higher in poor light and/or with moving subjects, nevertheless it's worth trying to keep it low, I feel - time to bracket ...?

It's liberating to not have this mindset and let the ISO go where it wants, but in the back of my mind I try and keep the ISO low as I want to know I've captured as much RAW data as I can for later processing and printing.

[microlight]

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.

[normhead]

The biggest disadvantages of high ISO are noise and loss of dynamic range. Indoors, the dynamic range part is negated by the low contrast conditions that don't have a lot of dynamic range even shooting at ISO 100. You just get a histogram with the left and right edges of the curve falling well within the edges of the graph. A sure sign you didn't use all the dynamic range the camera is capable of. So that leaves the added noise. As long as you're OK with the noise levels high ISO leads to no particular disadvantage.

But in images like these
The CameraVille image quality comparison K-1 vs K-1 MKII - Page 2 - PentaxForums.com
Any noise is just part of the mood.

[LensBeginner]

As @normhead pointed out, DR is something you get less of as you raise the ISO.


We have this boon, that Pentax cameras are generally pretty much ISO-invariant, and there are lots of situations where you need the shutter speed, but also the DR (e.g. night shots with dark streets and lights from lamp posts, neon signs...).


In those situations I'd rather shoot RAW, keep the ISO low(er), expose for the brightest details I want to preserve (i.e. no point in preserving specular highlights, or the filament of a light bulb, but one would want to keep some strongly lit area with some detail), and underexpose the rest accordingly.