M240 firmware tweaks

[jaapv]

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My justification is this:

 

The times when I want long exposures like that, I'm doing something unusual like astrophotography. The little pin pricks of light of stars are arranged in a noise like pattern anyway. If there are a couple more dots from noise, no one will notice. Without the ability to disable dark frame subtraction it is hard to connect the dots in star trails. You get little gaps.

 

Or if I'm doing something in near darkness like light painting a shape with a LED.

 

I can probably come up with three or four other scenarios where minimizing noise is less of a concern then having frames that have no time gap between them. In the scenarios when I want to turn dark frame subtraction off, I'm off the reservation of normal photography. I know that, I'll accept the consequences.

 

I love Leica's great image quality but there are times when I am willing to accept lower image quality to achieve a goal. It is just like when I'm zone focusing, I'll accept some not tack focus images as a trade off for the time advantage of being able to get a shot off quickly.

Yes, but if you look at the LCD of an M8, you will see that it is not just a few spots; it is an unusable image. Leica would have to implement the smearing type of in-camera noise reduction like other brands in that case. I doubt whether that is even possible on the present cameras, it would be a complete rewrite of the firmware. I think we will have to live with the fact that this is a design decision and use another (brand) camera for those applications for the time being.

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[keithlaban.co.uk]

Is a further firmware tweak likely to happen?  

[jaapv]

Not really. With the successor on the horizon the Typ 240 is more or less a done deal, warts and all. Leica will add new lens codes when needed by an update, and possibly fix a bug  when absolutely needed.

Like they will most probably fix the battery age bug.

[Adam]

There is no sense whatsoever to make any claims about the Signal/Noise ratio characteristics of the current M10 sensor based on the performance of the M8 sensor. Not even apples to oranges.

[sblutter]

I'm new to the 240...

 

There's a lot of complaint about B exposure times available on the Forum. 

 

There's a T setting mentioned in the manual - works fine for me.  I didn't test it extensively as I'm not a stargazer:

 

"THE B SETTING / T FUNCTION
With the B setting, the shutter remains open for as long as the shutter
release button is held down (up to a maximum of 60s; depending on
the ISO setting).

In conjunction with the self-timer, a T function is also available: If
B is set and the self-timer is activated by tapping the shutter release
button (see also p. 150), the shutter opens automatically after the
selected delay time. It then remains open until you press the shutter
release button a second time – you do not need to hold the button
down. This enables you to largely prevent any blurring, even with long
exposures, by pressing the shutter release button.

In both cases, the exposure meter is disabled; after the shutter is
released however the digital display in the viewfinder counts the
elapsed exposure time in seconds, for guidance."

--

Doesn't that solve the problem Flash Gordon's desire for 15 minute exposures?  Am I missing something?

[ileicabeer]

Doesn't that solve the problem Flash Gordon's desire for 15 minute exposures? Am I missing something?

Unfortunately not, 60s is the maximum shutter speed.

[Adam]

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Regardless of the settings, the camera will limit exposures to 60s and then shoot a dark frame with the same exposure time as your shot and then subtract noise detected by the dark frame from your shot. By design the camera is set up to double any long time exposure and limit these to 60s. There is no way to turn that off.

 

Increasing ISO shortens the 60s limit.

 

There is no way to have a 15min exposure even when using a self timer.

[jaapv]

There is no sense whatsoever to make any claims about the Signal/Noise ratio characteristics of the current M10 sensor based on the performance of the M8 sensor. Not even apples to oranges.

You're missing the point here completely; the M8 is slow enough to show the actual functioning of a black frame reduction operation on the LCD as it happens. Nobody is comparing sensors.

 

I guess an M10 sensor might have a vastly longer setting, though, it being a chimera. The M(typ240), however, has indeed 60 seconds.

[Adam]

Nope, I am not missing your point. It was simple enough.

 

However, the way the original image looks, and how successfully black frame reduction is applied depends on the S/N characteristics of the sensor, not the speed at which correction is done. The M8 has a different sensor than the current M, whose S/N characteristics are most likely to be much better than that of the M8.

 

The fact that the M8 is slow enough for you to see the uncorrected image is irrelevant, as is the the quality of the image that you see in the M8's LCD. This is because whatever is visible on the M8 LCD tells us nothing about the quality of the uncorrected images on the current M, which many people, by the way, call an M10. 

 

The only chimera in this thread is your version of the current M, which for some inexplicable reason has an M8 sensor in it. We can call it M8 (typ 10). Let me know when it comes out, so we can all get the a la carte version.

 

The point is simple, in future firmware releases for the current M we should be able to turn off black frame reduction, and we should be able to have the option to apply it later. This is hardly an outlandish proposal. Obfuscating the discussion with anecdotes about the M8 does not help the conversation.

[jaapv]

You're conflating the method with the result. I fully agree that the M240 will certainly show different heat noise than the M9 or M8. However, whether that is more or less is an unknown to me. There must be a reason that CCDs still reign in astrophotography with large telescopes.

[Adam]

You're conflating the method with the result. I fully agree that the M240 will certainly show different heat noise than the M9 or M8. However, whether that is more or less is an unknown to me. There must be a reason that CCDs still reign in astrophotography with large telescopes.

 

Hardly, but you appear to be confused as to why the M8 is irrelevant to this conversation, even though you admit you have no clue how as to how the M8 S/N compares to the M10.

 

Since you do not have a clue how they compare, it is pointless to assume that the noise you see in the M8 is the same or comparable to the M10. The need for dark frame reduction in a M10 cannot be justified based on what you see in the M8.

 

As far as dark frame reduction.  You cannot extrapolate the effectiveness of this type noise reduction based on data from one type of sensor to how it will behave in another type of sensor since the effectiveness of dark frame reduction depends on the individual S/N characteristics and how they change over time due to heat, etc.

 

As far as CMOS vs CCD noise. There is a lot of documentation out there and it is easy to find, so there is no need for innuendo.  Roughly, CMOS heats up faster but also captures more information faster, in general CCD is better with higher ISO long exposures since noise is less random.

 

But it is very likely a new CMOS sensor (M10) will be better overall as far as noise than an old CCD one (M8)

 

Anyway, for purposes of bulb exposure the CCD vs CMOS debate is moot. Publications such as Sky and Telescope regularly advise serious astro-photography with CMOS. And by the way they advise dark frame reduction after the whole session, not after each image!

 

http://www.skyandtelescope.com/astronomy-resources/astrophotography-tips/deep-sky-with-your-dslr/

 

 

Again, bottom line: Leica should allow its users to have a true bulb mode, and it should allow us to choose when to implement  dark frame reduction. There are no technical reasons not to do so. The only possible motivation is a PR one - they do not want examples of noisy images out there. That is not a good enough reason to cripple the camera.

[jdlaing]

You'll never get a bulb mode. ever.

[Adam]

For emphasis I would go:

 

N.E.V.E.R

 

Italics, even with repetition make it sound weak, not very assertive. As if you had doubts

[jdlaing]

No doubts here.

[Adam]

Well you are wrong. Not to have doubts that is.

 

And, I hope you are wrong about Leica. But time will tell.

[jdlaing]

For emphasis I would go:

 

N.E.V.E.R

 

Italics, even with repetition make it sound weak, not very assertive. As if you had doubts

 

NEVER.     Heat is the reason.

[Adam]

Heat is not the reason.

 

Not unless Leica's sensor is unique in giving out way more heat than other full frame CMOS cameras. Other full frames allow Bulb mode and customized dark frame noise reduction so there is no obvious reason that Leica cannot do the same.

[jdlaing]

Leica camera innards are jammed in tighter than others. They are also fussier on image results. Way less of a heat sink. I got this from a design engineer. Black frame subtraction I could see but not pure bulb. 

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[Adam]

Thanks. OK, I'll settle for customized black frame, which is more important for me than bulb, and an explanation like yours for lack of bulb in the current M.

 

Maybe the next M will have bulb, I believe they managed to have it in the SL whose body is not that much bigger.

[jdlaing]

Anybody know if there is a bulb time limit on the SL?