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Auto iso coming.


hansmezger

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It is correct.

 

 

Eh, no it isn't.

 

Perhaps you're confusing native iso settings (where analog electrical signal is amplified, i.e. a hardware 'push') and boosted iso setting (where digital data after that analog signal has been converted to digital is mathematically multiplied, i.e. a software 'push').

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No indeed.

 

Higher ISO settings amplify the sensor signals to create a digital RAW file.

(the more amplification, the more noise)

 

Post processing plays with the light values presented in the RAW file.

 

At least this is my understanding.

 

Nevertheless; where is the new firmware?

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Agree:

It is correct. [/quote.]

Leica M is 'ISO-free' in the range 200-1600.

Discussed here: Characterizing the Leica M240, part 3 | The Last Word

(For higher values on-sensor reduction of noise is implemented.)

Starting in the middle of the range, you have 1.5 stop in either direction,

or starting at ISO 400, 2 stops to 1600.

Signal-to-noise ratio is proportional to square-root of (N), N being number of photons reaching the individual pixels on the sensor. N is given by the aperture and time-settings,

independent of the ISO-setting. So if the aim is to keep aperture and time constant,

you dont achieve any noise improvement by varying the ISO.

 

 

If you experiment with some exposures and post processing

you will be able to determine it to be. [/quote.]

If you ARE able to see a difference in two such print, you rather have a

printer problem :)

Your printer does not give the same result although two identical files were sent out to it.:rolleyes:

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I believe this is incorrect. If it was true, you'd only ever need base iso, and pull exposure in the RAW-file in post. Obviously, that is not the same thing. At most RAW files, from even the best sensors, can be pushed 1-2 stops.

 

I think you may have misread my statement. I said that "our digital cameras really only have one true ISO, and the rest is pushing/pulling the exposure, whether in-camera or in the raw converter." My point is that there is no reason to shun the use of auto ISO, because, with digital, you're really only controlling the amount of light hitting the sensor with the aperture and shutter speed, and, unless you're shooting only at base ISO, the camera is providing the gain after the fact.

 

As to whether it is better to boost ISO in-camera, or in the raw converter, it is completely dependent on which sensor, raw converter and ISO settings you're talking about. Some cameras actually do better when boosted in the raw converter after a certain ISO. There's a long thread about this in regards to the M9, but that's a different topic.

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I think the analog vs digital gain issue is a bit more complicated than described in some dismissive comments above. I recommend reading all related posts in Jim Kasson's blog (very interesting).

 

In any case, all we want from Auto-ISO is the camera to balance the exposure given user-defined shutter speed and aperture.

I really don't care whether this is made pre or post ADC, as I expect respectable engineers to do that in-camera the way it makes more sense for the camera hardware.

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Frankly I couldn't give a damn what a photographer uses or how they use it. They will be judged by the images they create.

 

Exactly. I use auto-ISO all the time for colour with my Nikon D90.

 

It's a useful tool - I find it useful, especially as I don't use a tripod and have a 18-200 zoom. I set the minimum speed and it (the camera) does the rest, while I can concentrate on what I'm taking.

 

I realise this - and other such tools - isn't for everyone. But here's the thing... you, the photographer, gets to choose whether to use them or not.

 

It's called 'choice'. ;)

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I really don't care whether this is made pre or post ADC, as I expect respectable engineers to do that in-camera the way it makes more sense for the camera hardware.

 

Not to derail this thread any more, but, as Jim and many of us indicated in terms of the M9, it is not always better to use the camera hardware to boost ISO. It depends on the camera and raw converter being used.

 

Either way, a well thought out autoISO implementation is desirable.

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At this rate it seems like two poorly trained monkeys with ASR 33 teletypes and one seal balancing a ball on its nose are responsible for writing Leica firmware.

 

No one can blame Leica for strictly following IETF RFC-2795 procedures:

http://www.ietf.org/rfc/rfc2795.txt

 

It seems they are having issues finding an infinite number of monkeys, and unfortunately the firmware could not be completed by the end of January.

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I think you may have misread my statement. I said that "our digital cameras really only have one true ISO, and the rest is pushing/pulling the exposure, whether in-camera or in the raw converter." [...]

 

As to whether it is better to boost ISO in-camera, or in the raw converter, it is completely dependent on which sensor, raw converter and ISO settings you're talking about. Some cameras actually do better when boosted in the raw converter after a certain ISO. There's a long thread about this in regards to the M9, but that's a different topic.

 

 

Sorry I still don't know what you're on about as this is factually incorrect which I explained in my post. There's a huge difference in boosting sensor sensitivity in camera and to push RAW file in converter. The mere suggestion that it isn't is frankly absurd.

 

Regardless if different sensors respond differently to the two options, it still doesn't negate the hugely different nature of them.

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I think it needs to be remembered that our digital cameras really only have one true ISO, and the rest is pushing/pulling the exposure, whether in-camera or in the raw converter.

 

Allowing the camera to push the ISO automatically in-camera is a no-brainer, and autoISO with exposure compensation enabled in M mode is a logical implementation in a digital camera.

 

Do you know what that one value of ISO is for the m9 and the m240? I think you have made a really good point here.

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Sorry I still don't know what you're on about as this is factually incorrect which I explained in my post. There's a huge difference in boosting sensor sensitivity in camera and to push RAW file in converter. The mere suggestion that it isn't is frankly absurd.

 

Regardless if different sensors respond differently to the two options, it still doesn't negate the hugely different nature of them.

 

Of course there is a difference. One is using hardware amps (sometimes in conjunction with software,) and the other is purely software. I'm not sure why you think I'm suggesting otherwise.

 

My point is that there is no great philosophical reason not to have a fully featured autoISO option in the m240, even if you're a purist (my original point was directed at Gilgamesh.)

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I do not know the importance of the technical difficulty adding the option that many desire. Admittedly Leica are pretty stubborn and reluctant to change their views on issues "apparently" simple, for example, the years it took to encode the Apo-M 135 mm Telyt that although it should be used in M mode liveview, I still use the rangefinder with very reliable results.

 

Francisco.

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I do not know the importance of the technical difficulty adding the option that many desire. ...

Francisco.

 

Neither do I, particularly since this "option" restores the Auto ISO implementation found in all previous digital M bodies as well as the current M-E and Monochrom.

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