Highest acceptable ISO

jtstgeorge · 03-26-2019, 07:05 PM

Just wondering what the highest ISO everyone finds acceptable on thier k1 or k1 ii.

derekkite · 03-26-2019, 07:42 PM - **1 Like**

On the K1 II I have the iso range set to 12400. On the K1 it was set to half that. That is in TAV mode as high as the iso will go, and typically I stay below it except in situations where I can get a decent exposure at those high numbers.

rawr · 03-26-2019, 07:50 PM - **2 Likes**

Originally posted by jtstgeorge

what the highest ISO everyone finds acceptable on thier k1

Personally, I'm comfortable with the quality of K-1 images when shot at IS0 6400-12800 (or above, except for ridiculous ISO's like 25600), depending on the scene. I probably wouldn't shoot landscapes at ISO 6400, but for gigs or sports it's usually good.

By the standards of testing company DxO, ISO 3280 is the ceiling.

Pentax K-1 : Tests and Reviews - DxOMark

Up to ISO 3280, according to DxO you can be sure of excellent image quality with the K-1, defined as "a SNR of 30dB while keeping a good dynamic range of 9 EVs and a color depth of 18bits". Beyond ISO 3280, expect to see a slow, progressive decline in image quality.

"How far can ISO be increased while maintaining decent image quality? The DxOMark low-light ISO metric will give you this information.

The SNR indicates how much noise is present in an image compared to the actual image information (signal). The higher the SNR value, the better the image quality, as detail is not drowned out by noise. The SNR is given in dB, which is a logarithmic scale: an increase of 6 dB corresponds to doubling the SNR, which in turn equates to half the noise for the same signal. A SNR value of 30dB means excellent image quality. We have therefore defined low-light ISO as the highest ISO setting for a camera that allows it to achieve a SNR of 30dB while keeping a good dynamic range of 9 EVs and a color depth of 18bits."
DxOMark camera sensor testing protocol and scores - DxOMark

**interested_observer** · 03-26-2019, 10:10 PM

Obviously, the lower the better - since both dynamic range and coloring is better. I like to shoot in the night (especially in the Arizona summer), so light is important (what there is of it), and having excellent dynamic range lets me open up the shadows for details. That needs to be traded against just how long you want to push your exposure (especially if you are stitching). With my K5, it was ISO 1600, but with the K1 - I can use ISO 800 and get wonderful color and pull the shadow details out, and that was astro landscapes.

Now setting up the shot, I will turn up the ISO to 12,800 or 51,200 to do a 1 second shot to check level, and framing, then turn it back down for the shot. With my K5 as somewhat of a test shot, I used ISO 4000 one night and the foreground detail was wonderful (an old desert wash), so it all depends on a lot of factors.

The other thing is, the way I shoot - I get the white dot thermal noise. So, I need to make a decision as to using LENR or take some dark frames for post processing, or just tolerate it. That's just way out in the desert at nigh shooting astro. Dammed if you do and dammed if you don't. Shooting cityscapes, with some ambient light present - things go just fine. You have to make some real time decisions, trade offs, suck it up - and just shoot it. Perhaps shooting it several time, with slightly different setting.

MoiVous · 03-27-2019, 03:39 AM

It all depends on what you are doing.

I have a K1 mk II (upgraded from mk 1) and shoot a lot of street images - day and night, and have TAv set to 25600 maximum ISO for the night shots, and maximum 1600 in Av mode for daytime.
Yes there is noise at 25600, but for what I'm doing (including B&W conversion in Silver Efex) the noise is acceptable - I'm after an impression of the life around me. The K1 mk 1 had much more noise at that ISO.

Here is one at 16000 ISO:

Adults only

And another at 25600 ISO

Bar keep

To me these are acceptable and capture the moment - better than any smart phone BTW.

If I'm shooting portraits or macro or landscape etc I'll limit my ISO to 1600 or maybe 3200 with people - I can accept the level of noise in those images. It's not a lot different from film days - low ISO for the detail, push process and get plenty of grain with high ISO film for reportage or texture or to get the shot.

You will have to look at the images you create and find your level of acceptance. There is no hard and fast rule IMHO

Pikselisiirto · 03-27-2019, 05:24 AM

Personally I try to avoid lighting conditions which do not allow me to expose enough to saturate ISO 100. This is simply because saturated exposure at ISO 100 offers highest possible image quality. Even more with successful pixel shift. It is a bit waste because K-1 seems to be tuned towards higher ISO. I wish it had ISO 64 or lower, but still the best value camera out there for my needs. D810 costed almost a grand more at that time and it does not have pixel shift.

There is barrier when raising ISO is worser than software "gain" at lower ISO. When K-1 reach that barrier or is it just better to use highest possible ISO, if you can't expose enough?

**Merv-O** · 03-27-2019, 07:40 AM

I set my K-1 and KP to max out at 6400. With good post-processing I can suppress most SNR issues with some ambient light in the shot itself. RAW files pull out more obviously. If I can have a hand-held situation of 1/25 or faster than I can shoot well. The SR in both cameras is A1. On my K-5ii I go to 3200 and the pictures are fine for my needs. Obviously I wouldn't enlarge them to beyond 11x14, but rarely have occasion to regardless.
REH, on a different thread took pictures in the pitch dark at 254,000--the max setting on the KP and they were more than decent considering the extreme ISO. The IQ of these newer Pentax models is surprisingly good and the AF with newer issued lenses is a good as anyone.
I think it's fun to be a Pentaxian....

vector · 03-27-2019, 08:46 AM

I was just testing this out the other day. I have a bad tendency to want to keep my ISO as low as possible, preferably max of 800, but at the cost of shutter speed. Slow shutter speed is wrecking more images for me than ISO noise so I decided to spend a few hours testing it out. Did a bunch of shots on a tripod and handheld, repeated with K1 and K3. I concluded that in a low light situation 12800 is still very usable on my K1. I also concluded that 12800 on the K1 is better than 6400 on my K3. So I am retraining myself to let the ISO run 1600-6400 for indoors, low light stuff, and even push to 12800 to keep that shutter speed up. At higher ISO what I am really losing is the ability to crop as the detail degrades, but at normal viewing sizes it is quite good.

**Erictator** · 03-27-2019, 02:01 PM

Like others here, the lower the better... BUT... and there is a lot of buts here... it depends on some other factors for me.

I set my auto iso to stay below 3200... because that is a number I can "think" in from my film days and I know I can make the RAW look good in PP. BUT... I prefer the look of ISO 800 or less, especially if I'll be doing any heavy cropping.

BUT... I find there is a big difference between using ISO 3200 in dark situations with a lot of shadow, where I might find the noise objectionable, opposed to using ISO 3200 in daylight just to get the shutter speed up to freeze action. In daylight, the grain from ISO 3200 is negligible, and might even add the appearance of more detail to a patterned subject. In the dark situations, spot metering becomes essential for me with AF spot linked to AE spot, then I can just expose for the subject and let the blacks go black and they look fine. It all really just depends... well, for me anyway.
Eric

Fenwoodian · 03-27-2019, 03:12 PM

.
I own many different camera systems. I use my K-1s for my serious/professional captures. Each K-1 is always set to base ISO. Then from base ISO, I will adjust shutter speed and aperture accordingly.

I'm all about capturing the best possible image file (for making large prints). I can detect image degradation at any ISO above base, and that's simply not acceptable to me - ever.

If an image is not important enough to do optimally, I'll substitute a smaller sensor camera for my full frame K-1.

jtstgeorge · 03-27-2019, 07:30 PM

Originally posted by interested_observer

Obviously, the lower the better - since both dynamic range and coloring is better. I like to shoot in the night (especially in the Arizona summer), so light is important (what there is of it), and having excellent dynamic range lets me open up the shadows for details. That needs to be traded against just how long you want to push your exposure (especially if you are stitching). With my K5, it was ISO 1600, but with the K1 - I can use ISO 800 and get wonderful color and pull the shadow details out, and that was astro landscapes.

Now setting up the shot, I will turn up the ISO to 12,800 or 51,200 to do a 1 second shot to check level, and framing, then turn it back down for the shot. With my K5 as somewhat of a test shot, I used ISO 4000 one night and the foreground detail was wonderful (an old desert wash), so it all depends on a lot of factors.

The other thing is, the way I shoot - I get the white dot thermal noise. So, I need to make a decision as to using LENR or take some dark frames for post processing, or just tolerate it. That's just way out in the desert at nigh shooting astro. Dammed if you do and dammed if you don't. Shooting cityscapes, with some ambient light present - things go just fine. You have to make some real time decisions, trade offs, suck it up - and just shoot it. Perhaps shooting it several time, with slightly different setting.

great tip

rawr · 03-28-2019, 12:19 AM

FWIW, Imaging Resource have a handy display of the High ISO NR performance of the K-1, stepping the ISO up from ISO 100 to ISO 204k, and showing the effects of the in-camera JPEG noise reduction settings ON/OFF/RAW along the way:

Pentax K-1 Review - High ISO NR

The same test should be interesting with the K-1 II, once they complete their review of that camera.

**Rondec** · 03-28-2019, 02:33 AM

I don't usually shoot over 25K iso. The biggest issue isn't so much noise, but dynamic range. There's just a lot less detail and things sort of look washed out.

This is a shot of New Orleans I took at iso 10,000. It is decent, but honestly, it would have been way better if I had had a tripod a long.

jeromebertrem · 03-28-2019, 05:47 AM

As a amateur I keep the ISO as low as possible and up it only when needed. But I am still learning. :-)

Anyway, is there a situation imaginable where one would use max ISO 819200??

rawr · 03-28-2019, 01:24 PM

Originally posted by jeromebertrem

Anyway, is there a situation imaginable where one would use max ISO 819200??

I guess Ricoh had some usage cases in mind when they built that capability into the camera. Maybe it can work with long exposures or multi-exposures?

Super-high ISO is also simply a feature race and spec sheet padding game played between camera makers. I think Canon started it off when it claimed ISO 204,800 capabilities in the EOS-1 DX in 2011, to fight against Nikon's high ISO D3 and D4 series of cameras, which also claimed ridiculous high ISO capabilities, and everyone has been doing the same ever since. Now even smartphones (eg Huawei P30 Pro) are claiming ISO 409 600.

03-26-2019, 07:05 PM	#1
jtstgeorge New Member Join Date: Jan 2016 Location: St George, Utah Photos: Gallery Posts: 24	Highest acceptable ISO Just wondering what the highest ISO everyone finds acceptable on thier k1 or k1 ii.

03-27-2019, 03:39 AM	#5
MoiVous Veteran Member Join Date: Sep 2008 Location: Adelaide, South Australia Photos: Gallery Posts: 677	It all depends on what you are doing. I have a K1 mk II (upgraded from mk 1) and shoot a lot of street images - day and night, and have TAv set to 25600 maximum ISO for the night shots, and maximum 1600 in Av mode for daytime. Yes there is noise at 25600, but for what I'm doing (including B&W conversion in Silver Efex) the noise is acceptable - I'm after an impression of the life around me. The K1 mk 1 had much more noise at that ISO. Here is one at 16000 ISO: Adults only And another at 25600 ISO Bar keep To me these are acceptable and capture the moment - better than any smart phone BTW. If I'm shooting portraits or macro or landscape etc I'll limit my ISO to 1600 or maybe 3200 with people - I can accept the level of noise in those images. It's not a lot different from film days - low ISO for the detail, push process and get plenty of grain with high ISO film for reportage or texture or to get the shot. You will have to look at the images you create and find your level of acceptance. There is no hard and fast rule IMHO Last edited by MoiVous; 03-27-2019 at 03:55 AM.

03-27-2019, 03:12 PM	#10
Fenwoodian Pentaxian Join Date: Apr 2015 Location: USA Photos: Gallery \| Albums Posts: 2,874	. I own many different camera systems. I use my K-1s for my serious/professional captures. Each K-1 is always set to base ISO. Then from base ISO, I will adjust shutter speed and aperture accordingly. I'm all about capturing the best possible image file (for making large prints). I can detect image degradation at any ISO above base, and that's simply not acceptable to me - ever. If an image is not important enough to do optimally, I'll substitute a smaller sensor camera for my full frame K-1. Last edited by Fenwoodian; 03-27-2019 at 03:18 PM.

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03-26-2019, 07:42 PM - 1 Like	#2
derekkite Pentaxian Join Date: Sep 2011 Location: Nelson B.C. Posts: 3,782	On the K1 II I have the iso range set to 12400. On the K1 it was set to half that. That is in TAV mode as high as the iso will go, and typically I stay below it except in situations where I can get a decent exposure at those high numbers.

03-26-2019, 07:50 PM - 2 Likes	#3
rawr Veteran Member Join Date: Jun 2009 Posts: 11,913	Originally posted by jtstgeorge what the highest ISO everyone finds acceptable on thier k1 Personally, I'm comfortable with the quality of K-1 images when shot at IS0 6400-12800 (or above, except for ridiculous ISO's like 25600), depending on the scene. I probably wouldn't shoot landscapes at ISO 6400, but for gigs or sports it's usually good. By the standards of testing company DxO, ISO 3280 is the ceiling. Pentax K-1 : Tests and Reviews - DxOMark Up to ISO 3280, according to DxO you can be sure of excellent image quality with the K-1, defined as "a SNR of 30dB while keeping a good dynamic range of 9 EVs and a color depth of 18bits". Beyond ISO 3280, expect to see a slow, progressive decline in image quality. "How far can ISO be increased while maintaining decent image quality? The DxOMark low-light ISO metric will give you this information. The SNR indicates how much noise is present in an image compared to the actual image information (signal). The higher the SNR value, the better the image quality, as detail is not drowned out by noise. The SNR is given in dB, which is a logarithmic scale: an increase of 6 dB corresponds to doubling the SNR, which in turn equates to half the noise for the same signal. A SNR value of 30dB means excellent image quality. We have therefore defined low-light ISO as the highest ISO setting for a camera that allows it to achieve a SNR of 30dB while keeping a good dynamic range of 9 EVs and a color depth of 18bits." DxOMark camera sensor testing protocol and scores - DxOMark

03-26-2019, 10:10 PM	#4
interested_observer Loyal Site Supporter Join Date: Jun 2009 Location: Tumbleweed, Arizona Photos: Gallery \| Albums Posts: 5,707	Obviously, the lower the better - since both dynamic range and coloring is better. I like to shoot in the night (especially in the Arizona summer), so light is important (what there is of it), and having excellent dynamic range lets me open up the shadows for details. That needs to be traded against just how long you want to push your exposure (especially if you are stitching). With my K5, it was ISO 1600, but with the K1 - I can use ISO 800 and get wonderful color and pull the shadow details out, and that was astro landscapes. Now setting up the shot, I will turn up the ISO to 12,800 or 51,200 to do a 1 second shot to check level, and framing, then turn it back down for the shot. With my K5 as somewhat of a test shot, I used ISO 4000 one night and the foreground detail was wonderful (an old desert wash), so it all depends on a lot of factors. The other thing is, the way I shoot - I get the white dot thermal noise. So, I need to make a decision as to using LENR or take some dark frames for post processing, or just tolerate it. That's just way out in the desert at nigh shooting astro. Dammed if you do and dammed if you don't. Shooting cityscapes, with some ambient light present - things go just fine. You have to make some real time decisions, trade offs, suck it up - and just shoot it. Perhaps shooting it several time, with slightly different setting.

03-27-2019, 05:24 AM	#6
Pikselisiirto Forum Member Join Date: Aug 2018 Posts: 57	Personally I try to avoid lighting conditions which do not allow me to expose enough to saturate ISO 100. This is simply because saturated exposure at ISO 100 offers highest possible image quality. Even more with successful pixel shift. It is a bit waste because K-1 seems to be tuned towards higher ISO. I wish it had ISO 64 or lower, but still the best value camera out there for my needs. D810 costed almost a grand more at that time and it does not have pixel shift. There is barrier when raising ISO is worser than software "gain" at lower ISO. When K-1 reach that barrier or is it just better to use highest possible ISO, if you can't expose enough?

03-27-2019, 07:40 AM	#7
Merv-O Loyal Site Supporter Join Date: Aug 2018 Location: Philadelphia Photos: Albums Posts: 2,098	I set my K-1 and KP to max out at 6400. With good post-processing I can suppress most SNR issues with some ambient light in the shot itself. RAW files pull out more obviously. If I can have a hand-held situation of 1/25 or faster than I can shoot well. The SR in both cameras is A1. On my K-5ii I go to 3200 and the pictures are fine for my needs. Obviously I wouldn't enlarge them to beyond 11x14, but rarely have occasion to regardless. REH, on a different thread took pictures in the pitch dark at 254,000--the max setting on the KP and they were more than decent considering the extreme ISO. The IQ of these newer Pentax models is surprisingly good and the AF with newer issued lenses is a good as anyone. I think it's fun to be a Pentaxian....

03-27-2019, 08:46 AM	#8
vector Pentaxian Join Date: May 2015 Location: Alberta Posts: 713	I was just testing this out the other day. I have a bad tendency to want to keep my ISO as low as possible, preferably max of 800, but at the cost of shutter speed. Slow shutter speed is wrecking more images for me than ISO noise so I decided to spend a few hours testing it out. Did a bunch of shots on a tripod and handheld, repeated with K1 and K3. I concluded that in a low light situation 12800 is still very usable on my K1. I also concluded that 12800 on the K1 is better than 6400 on my K3. So I am retraining myself to let the ISO run 1600-6400 for indoors, low light stuff, and even push to 12800 to keep that shutter speed up. At higher ISO what I am really losing is the ability to crop as the detail degrades, but at normal viewing sizes it is quite good.

03-27-2019, 02:01 PM	#9
Erictator Site Supporter Join Date: Jul 2011 Photos: Gallery \| Albums Posts: 3,345	Like others here, the lower the better... BUT... and there is a lot of buts here... it depends on some other factors for me. I set my auto iso to stay below 3200... because that is a number I can "think" in from my film days and I know I can make the RAW look good in PP. BUT... I prefer the look of ISO 800 or less, especially if I'll be doing any heavy cropping. BUT... I find there is a big difference between using ISO 3200 in dark situations with a lot of shadow, where I might find the noise objectionable, opposed to using ISO 3200 in daylight just to get the shutter speed up to freeze action. In daylight, the grain from ISO 3200 is negligible, and might even add the appearance of more detail to a patterned subject. In the dark situations, spot metering becomes essential for me with AF spot linked to AE spot, then I can just expose for the subject and let the blacks go black and they look fine. It all really just depends... well, for me anyway. Eric

03-27-2019, 07:30 PM	#11
jtstgeorge New Member Join Date: Jan 2016 Location: St George, Utah Photos: Gallery Posts: 24 Original Poster	Originally posted by interested_observer Obviously, the lower the better - since both dynamic range and coloring is better. I like to shoot in the night (especially in the Arizona summer), so light is important (what there is of it), and having excellent dynamic range lets me open up the shadows for details. That needs to be traded against just how long you want to push your exposure (especially if you are stitching). With my K5, it was ISO 1600, but with the K1 - I can use ISO 800 and get wonderful color and pull the shadow details out, and that was astro landscapes. Now setting up the shot, I will turn up the ISO to 12,800 or 51,200 to do a 1 second shot to check level, and framing, then turn it back down for the shot. With my K5 as somewhat of a test shot, I used ISO 4000 one night and the foreground detail was wonderful (an old desert wash), so it all depends on a lot of factors. The other thing is, the way I shoot - I get the white dot thermal noise. So, I need to make a decision as to using LENR or take some dark frames for post processing, or just tolerate it. That's just way out in the desert at nigh shooting astro. Dammed if you do and dammed if you don't. Shooting cityscapes, with some ambient light present - things go just fine. You have to make some real time decisions, trade offs, suck it up - and just shoot it. Perhaps shooting it several time, with slightly different setting. great tip

03-28-2019, 12:19 AM	#12
rawr Veteran Member Join Date: Jun 2009 Posts: 11,913	FWIW, Imaging Resource have a handy display of the High ISO NR performance of the K-1, stepping the ISO up from ISO 100 to ISO 204k, and showing the effects of the in-camera JPEG noise reduction settings ON/OFF/RAW along the way: Pentax K-1 Review - High ISO NR The same test should be interesting with the K-1 II, once they complete their review of that camera.

03-28-2019, 02:33 AM	#13
Rondec Loyal Site Supporter Join Date: Mar 2009 Location: Gladys, Virginia Photos: Gallery Posts: 27,653	I don't usually shoot over 25K iso. The biggest issue isn't so much noise, but dynamic range. There's just a lot less detail and things sort of look washed out. This is a shot of New Orleans I took at iso 10,000. It is decent, but honestly, it would have been way better if I had had a tripod a long.

03-28-2019, 05:47 AM	#14
jeromebertrem Forum Member Join Date: Nov 2013 Location: Brussels Photos: Albums Posts: 55	As a amateur I keep the ISO as low as possible and up it only when needed. But I am still learning. :-) Anyway, is there a situation imaginable where one would use max ISO 819200??

03-28-2019, 01:24 PM	#15
rawr Veteran Member Join Date: Jun 2009 Posts: 11,913	Originally posted by jeromebertrem Anyway, is there a situation imaginable where one would use max ISO 819200?? I guess Ricoh had some usage cases in mind when they built that capability into the camera. Maybe it can work with long exposures or multi-exposures? Super-high ISO is also simply a feature race and spec sheet padding game played between camera makers. I think Canon started it off when it claimed ISO 204,800 capabilities in the EOS-1 DX in 2011, to fight against Nikon's high ISO D3 and D4 series of cameras, which also claimed ridiculous high ISO capabilities, and everyone has been doing the same ever since. Now even smartphones (eg Huawei P30 Pro) are claiming ISO 409 600.