[Ropuchy]

Hello!

I've been browsing the Pentax site and saw that their K-1 Mk2 and KP have a maximum ISO of 819,200!
What are the benefits or drawbacks of having a sensor capable of such high ISO?
What's the use case for an ISO so high? Very long exposures, high f-stop, and very low light all at once?
Does having a sensor with this capability increase/decrease the effectiveness of lower ISOs?


Sorry if this question misses the point or something. I'm quite a newbie to digital photography and whatnot.

[Adam]

The highest ISO settings are mostly for bragging rights, but their presence implies good performance at lower settings.

You can see some examples here:

Pentax K-1 II vs K-1 Noise Performance - Hands-On Tests | PentaxForums.com

[pakinjapan]

so people can get that dream shot while the cap still on.

[UncleVanya]

I think it is useful when you absolutely want the shot and you'd rather sacrifice quality than miss it. Here's a shot of my dad made at ISO 25600 on a K-3. Given that the max ISO on the K-3 is 51200 and the K-1 is over 3 stops better than the K-1 this isn't much different than shooting a K-1 at ISO 204800 or higher.

[clackers]

Given that the max ISO on the K-3 is 51200 and the K-1 is over 3 stops better than the K-1 this isn't much different than shooting a K-1 at ISO 204800 or higher.

If you go to Imaging Resource "Comparometer" ? Digital Camera Image Comparison Page and choose the K-1 at ISO 204800 it's very bad, Brad!

And the ISO 51200 is a throwaway for mine, too, sadly.

[mikeSF]

a couple come to mind:

1) If you are shooting handheld and it is very dark, but you are willing to sacrifice image quality to have any image at all.

2) Stacking. Several successive high ISO images may be stacked and blended to create a less noisy composite image. I had the necessity to do this exactly once earlier this year and the results were surprisingly good.

_____
3) forgot to mention earlier, but yes, framing and focusing a night shot before shooting it "for real" is my normal work flow with high ISO. I'll jam it up to save time waiting for longer exposures to burn in.

[HarisF1]

The main example I would use is for composing an image in low light conditions (such as astrophotography). I'd much rather do a 1 second exposure at a throwaway 51200 ISO than wait 30 seconds at my intended final ISO setting.

When I did astro with my K-3 this was invaluable for focus checking.

[kiwi_jono]

I guess if you were caught in very poor light, without a tripod, then the highest levels might allow you capture something that you otherwise might not. But that said on the K-1, the highest I would normally consider using is 51200 (and then take a few shots and hope for one without blur).

With some PP NR (in RawTherapee) the best colour image quality I got with the K-1 and ISO 204800 was:


Obviously the results look better if you convert to black and white (where some noise can look interesting anyway).
The funny thing is it was a very dull day but I was shooting at 1/8000 and f8!

ISO 800K on the K-1 II looks a lot worse again (no idea why they bothered!)

[Excalibor]

I think it is useful when you absolutely want the shot and you'd rather sacrifice quality than miss it. Here's a shot of my dad made at ISO 25600 on a K-3. Given that the max ISO on the K-3 is 51200 and the K-1 is over 3 stops better than the K-1 this isn't much different than shooting a K-1 at ISO 204800 or higher.

Gorgeous portrait!

I agree wholeheartedly with you: it's better a noisy picture than no picture at all! High ISO allows that and it's amazing how technology empowers us...

Cheers!

P.S.- again, amazing portrait! And the b&w treatment in post was the right idea, to work with the noise instead of fighting it... Thumbs up!

Edit: mobile keyboard made noise a moose xD

[LensBeginner]

a couple come to mind:

1) If you are shooting handheld and it is very dark, but you are willing to sacrifice image quality to have any image at all.

2) Stacking. Several successive high ISO images may be stacked and blended to create a less noisy composite image. I had the necessity to do this exactly once earlier this year and the results were surprisingly good.

May I ask you what was the subject of point 2)? I'm curious
From "extremely high ISO", as the title said it's gonna be a chore... let's say the starting image is shot at ISO 204'800... you'll need to stack 25 images just to get to a level of noise comparable with ISO 6400 (5 stops)...

[alpheios]

Just as HarisF1 said before I think the main purpose is for composing and checking focus in the night. Since Pentax cameras have lots of features that are targeted at landscape and especially astro photographers that is probably what it's meant for. Of course ISOs that high are not usable for normal photography.
I do a lot of astro, nightscape and lightpainting stuff with my K-1 and having the ability to compose with liveview in almost pitch black darkness or taking a quick testshot to check and adjust compostion and focus without having to wait minutes for each exposure is a really helpful tool.

[kypfer]

How about street/surveillance photography at night? Being able to produce a recognisable image in a situation where a flash might be deemed "unsociable" could be considered an advantage in some circumstances!

[disconnekt]

To me, pretty much almost every Dslr that has come out the last ~4 or so years can produce good usable images at ISO 51,200, though some may need some small PP massageing to get it there. Anything over that to me is pretty much in the "Use In Case Of Emergency" type of situation.

[officiousbystander]

100 ISO when you want a beautiful image.
819,200 ISO when you need evidence.

[othar]

a couple come to mind:

1) If you are shooting handheld and it is very dark, but you are willing to sacrifice image quality to have any image at all.

2) Stacking. Several successive high ISO images may be stacked and blended to create a less noisy composite image. I had the necessity to do this exactly once earlier this year and the results were surprisingly good.

May I ask why it wasn't able to take a longer exposure instead (was the area shaking somehow?) because after stacking, any moving object in the picture would either be noisy as hell or just ghostlike thin, not quite the same but similar to what you get with a longer exposure anyhow.

Edit: I guess it might makes sense if you had no tripod with you to get a stable camera position, too.