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02-17-2018, 09:56 AM   #301
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QuoteOriginally posted by biz-engineer Quote
Nikon is better.
For the price tag, it has to.

02-17-2018, 10:03 AM   #302
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QuoteOriginally posted by biz-engineer Quote
But if we add a 1 stop ND filter in front of the lens, at ISO100 we get shutter speed twice as long, so it's like having ISO50?
But what benefit would you get other than being able to use wider aperture and/or slower shutter??
02-17-2018, 10:12 AM   #303
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QuoteOriginally posted by reh321 Quote
But what benefit would you get other than being able to use wider aperture and/or slower shutter??
Nothing. The synthetic low ISO settings on other cameras are just to avoid ND filters (or CPLs, which by conincidence just tend to kill about 1 stop of light).
If you look at sensor measurements you see that the lowest ISO usually is flat versus the setting one stop higher.
02-17-2018, 10:25 AM - 1 Like   #304
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QuoteOriginally posted by reh321 Quote
But what benefit would you get other than being able to use wider aperture and/or slower shutter??
QuoteOriginally posted by beholder3 Quote
Nothing. The synthetic low ISO settings on other cameras are just to avoid ND filters (or CPLs, which by conincidence just tend to kill about 1 stop of light).
If you look at sensor measurements you see that the lowest ISO usually is flat versus the setting one stop higher.
Not only that, using a simulated "low ISO" actually reduces the dynamic range ever so slightly. Base ISO will always give the least noise and best dynamic range...

02-17-2018, 10:28 AM - 2 Likes   #305
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QuoteOriginally posted by biz-engineer Quote
But if we add a 1 stop ND filter in front of the lens, at ISO100 we get shutter speed twice as long, so it's like having ISO50?
Yes, it is, and it's for the same reason that Leica M Monochrom cameras (without Bayer filter) have a higher base ISO than their standard counterparts. Yet the sensor is the same.

Leica M (Typ 240): ISO 200 is the base sensitivity.

Leica M Monochrom (Typ 246): ISO 320 is the base sensitivity.
02-17-2018, 11:03 AM   #306
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I know olympus had "low iso" setting that would overexpose native iso 200 and then correct that in camera, effectively giving a cleaner image and slower shutter speed. However it did have a chance to blow out highlights due to overexposure in the first place. I mean I don't see why we couldn't have it as an option, to have even less noise in right situations.
02-17-2018, 11:04 AM   #307
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QuoteOriginally posted by ogl Quote
Good news
Nikon D850 has real ISO64 (measured ISO44) and D810 (measured as ISO47)


But I don't want a Nikon.

02-17-2018, 11:08 AM - 7 Likes   #308
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The physics of ISO on digital is not like physics of ISO on film. Lower native base ISO on a digital sensor does not automatically imply finer grain, lower noise, or smoother transitions like it tends to on film. In fact, a lower base ISO can indicate a worse sensor.

It's easy enough to lower the base ISO of a sensor by increasing the density of the color filter material, using no microlenses, or designing a sensor with a poor fill factor. But none of that makes the picture any sharper or less noisy.

And some improvements in sensor technology such as a better quantum efficiency will increase the base ISO without increasing the noise. The result is a better sensor despite the higher ISO.

The only sensor design change that both reduces ISO and improves IQ is to increase the well-depth which is the ability of the pixel to store charge. Semiconductor physics makes that very hard to do and involves other trade-offs.

There are some tricks to operating the sensor closer to it's analog saturation point (pushing the utilized well-depth to the limits) that slightly increase some kinds of IQ but reduce others and require a bit of baking of the RAW because the sensor is no longer linear at the lowest ISO setting. Those weird non-linear measurements of actual vs. dial ISO on the Nikon D850 suggest that's what they are doing but it would take a more careful analysis to see what's really going on.

The bottom line is that Pentax could order ISO 25 sensors from Sony but the IQ at ISO 25 would be no better than the current K-1's ISO 100 performance and ISO6400 on the low-ISO sensor would look like ISO 25600 on the current K-1. It would be akin to installing a non-removable ND filter and what's the value of that?
02-17-2018, 11:34 AM - 7 Likes   #309
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QuoteOriginally posted by Kunzite Quote
So the technical expertise deciding that K-1 Mark II is no good can be resumed to two words: "baked" and "massaged".
I think most agree that a baked Raw file is gross like half cooked slimy porridge. But massage it a little, like a fine Kobe beef...and you can have something marvelous.

I'm personally concerned with the 'accelerator unit', this sounds like a modern convenience like a microwave, designed to give instant but bland and flavourless gratification. They should have called it the 'slow roaster unit' if they wanted to evoke sumptuous flavour and the kind of quality we're willing to wait for. I know I'd be willing to hold out a few extra seconds while my raw files simmer to perfection over a delicate mesquite smoke.
02-17-2018, 11:59 AM   #310
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I don't know what functions are incorporated in the accelerator unit, but if it speeds up the processing of the sensor data to the raw data it would be fine for the K-1.
If it improves the noise reduction without loosing details and dynamic range even in the raw data this would be fine too.
02-17-2018, 05:11 PM - 3 Likes   #311
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QuoteOriginally posted by BrianR Quote
They should have called it the 'slow roaster unit' if they wanted to evoke sumptuous flavour and the kind of quality we're willing to wait for.
Or for a bit more je ne sais quoi, Pentax could call it their sous vide unit.

"You can have your file(t) RAW if you wish, sir, but may I suggest the CONFIT"

"Mmmm, tasty! I'll have mine with a glass of Burgundy."

France is, after all, one of their biggest markets outside of Japan, isn't it?
02-17-2018, 05:45 PM - 7 Likes   #312
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QuoteOriginally posted by joergens.mi Quote
If it improves the noise reduction without loosing details and dynamic range even in the raw data this would be fine too.
Yep, I don't want any baking where some trade-off algorithm is applied based on all the data.

That stuff should be reserved for a JPG, IMHO. And yes, I do understand other brands such as Sony and the m43 guys are more guilty of this. Like BigMackCam, I shoot Sony too and understand his concerns about their compressed RAW files, where he confirmed edge artifacts were created under certain conditions.

Just give me the RAW and I'll selectively apply the corrections myself in post. I may be happy just to crush the blacks in a noisy background shadow, let highlights blow where they don't matter in a scene and even crop out an area rather than let a global setting affect other areas in the picture.

Or give me a menu item to switch it off and see the difference for myself.


Ah, that was an emotional purge, thanks in advance for tolerating it.

If there's no downside to a noise reduction method, fine!

Last edited by clackers; 02-17-2018 at 05:50 PM.
02-17-2018, 06:09 PM - 3 Likes   #313
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QuoteOriginally posted by clackers Quote
Or give me a menu item to switch it off and see the difference for myself.
Of course, this is the ideal solution... Bake the RAW file all you like, so long as that's selectable, and I can switch it off if I don't like, want or need it
02-17-2018, 07:43 PM   #314
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Baked is much healthier than fried.


Less trans fats and all.
02-17-2018, 08:57 PM - 1 Like   #315
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QuoteOriginally posted by photoptimist Quote

The bottom line is that Pentax could order ISO 25 sensors from Sony but the IQ at ISO 25 would be no better than the current K-1's ISO 100 performance and ISO6400 on the low-ISO sensor would look like ISO 25600 on the current K-1. It would be akin to installing a non-removable ND filter and what's the value of that?
How do you know it? It's absolutely unfounded what you said.

ISO80 of K-5IIs is the best ISO for this camera.
Nikon D850 and 810's ISO64 are the same.
Better DR, SBR18%, Tonal range, Colour Sensitivity in all aspects and e.t.c.

Not much higher, but HIGHER.

Last edited by ogl; 02-17-2018 at 09:07 PM.
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