Is The Mars Rover Cam Life-Blind?

What color is both chlorophyll A and B with both L256 and L456 uisng NASA's method of creating "almost" true color Jpegs for the press page?

If it is not orange, then what color is it?

ArchAngel, do you have BarryKearns
on "ignore?"

Sorry, I am not ignoring anyone.

I am trying to move past the point of the above question.

Originally posted by ArchAngel
Sorry, I am not ignoring anyone.

I am trying to move past the point of the above question.

Of course you're trying to "move past", because the explanations that I've pointed out illustrate how off-track you are.

So instead, you set up these straw-man arguments about L256 and L456, when I've already explained what plant life would look like under L356.

Why is it that you consistently fail to acknowledge that?

Originally posted by BarryKearns
...there are colors that your computer can never display...

Such as?

"Why is it that you consistently fail to acknowledge that?"

Because the images at the Press Page are either L256, or L456.

[Edited on 14-2-2004 by ArchAngel]

Do all forms of chlorophyll respond to light the same, and what form[s] are present in the differnent types of algae?

Originally posted by ArchAngel

Originally posted by BarryKearns
...there are colors that your computer can never display...

Such as?

Go back to Kano's original thread on the subject, which includes a nice composite picture of the human-vision color space, with a computer RGB space triangle spuerimposed over it.

Anything outside the triangle is a color that cannot be accurately represented.

Then realize that the triangle in this case is not a continuous structure... it is a set of discrete POINTS, 256 along each of the three triangular axes. Anything that doesn't land EXACTLY on one of those points (laid out in a 256x256x256 array) is a color that cannot be displayed.

We don't have names for them all, because there are an infinite number of them.

The useful analogy in this case is a comparison of the whole numbers to the set of "real" numbers. There are an infinite number of real numbers that cannot be represented as integers. Integers are a vanishingly small set when compared to the reals.

However, whole numbers are often a useful APPROXIMATION of a real number, despite the fact that the number cannot be accurately represented as a whole number.

[Edited on 2-14-2004 by BarryKearns]

Originally posted by ArchAngel
"Why is it that you consistently fail to acknowledge that?"

Because the images at the Press Page are either L256, or L456.

[Edited on 14-2-2004 by ArchAngel]

So now you're simply going to change your argument from "the Cam is color-blind" to "they are using poor mixes of filters for their public-display color composites"?

Those are NOT the same argument by a country mile.

Poor use of a tool does not mean that the tool is broken.

Do you want to scrap and retract your entire argument about the CAMERA being flawed, or would you like to stay on subject?

What color is both chlorophyll A and B with both L256 and L456 using NASA's method of creating 24bit color RGB Jpegs for the press page?

If it is not orange, then what color is it?

Before we go much further, ArchAngel, I have a question or two:

Do you realize that there are OTHER ways to use the data coming back from various filters in order to detect the presence or absence of something... beyond a simple RGB mix and then gawking at it with your eyes?

Do you recognize that there are other frequency signatures beyond the limited subset that humans see, which are useful for distinguishing one type of object from another... even something like chlorophyll?

Do you recognize that single-channel data can be compared to other single-channel data, even if they are NEVER combined into a human-friendly composite, and still provide useful signals for detection?

Are you aware that some of the most successful tests for chlorophyll concentrations ON EARTH using hyperspectral imagery come from a comparison of frequency responses OUTSIDE THE HUMAN VISION RANGE?

Originally posted by ArchAngel
What color is both chlorophyll A and B with both L256 and L456 using NASA's method of creating 24bit color RGB Jpegs for the press page?

If it is not orange, then what color is it?

You're asking a non-sequitur question for this thread.

The Pancam does not create color mixes for press pages.

It is the Pancam that you claimed was "life-blind", not the NASA color team.

Would you like to retract that, or are you going to take a consistently Orwellian stand and pretend that the argument in progress is actually a completely different one?

Do you realize that there are OTHER ways to use the data coming back from various filters in order to detect the presence or absence of something..

I understand that is true, and hoped to use it to look, but the strong red absorption data is missing.

Different types of blue-green algae will look different colors using different filter combinations.

In some cases it would make our imaginary algae look the same color as the martian dust....

The Pancam does not create color mixes for press pages.

The images on the press page are created from data obtained from the pancam.

You're asking a non-sequitur question for this thread.

The answer to the question is the very foundation of the thread.

Originally posted by ArchAngel

The Pancam does not create color mixes for press pages.

The images on the press page are created from data obtained from the pancam.

Yes, but I say again... poor use of a tool does not mean that the tool is BROKEN.

You're changing the argument 90% of the way through. Frankly, I consider that a rather scummy debating tactic.

Those images were created using a small SUBSET of the data from the Pancam, and has been presented in a particular way. That presentation is not the "fault" of the Pancam.

If you'd like to stay on-topic, please remove any arguments related to how the team has CHOSEN to use the tool, and CHOSEN to present the data... and instead stick to the capabilities of the tool if used properly.

Your claim is that the Pancam is "life-blind", yet what we seem to be seeing is that your definition is shrinking in wide swaths with subsequent posts.

It is only "life-blind" if it cannot detect ANY life... not if there is one hypothetical lifeform that might not show up the way you want to see it, in some particular presentation form.

There are a great many ways to use the Pancam to detect a wide, wide variety of forms of life (despite the fact that this is not the primary mission).

Is it theoretically possible that there might exist some hypothetical form of life on Mars that is not detectable using the tool? Sure, almost anything is possible.

Is it likely? I seriously doubt it, and doubt it completely if the sole evidence is what you've presented so far. It would have to be ridiculously well-engineered life to somehow "fall into the cracks" yet have no other components that were detectable at all.

It would be magical, anti-Pancam algae... Cornell kryptonite.

"Yes, but I say again... poor use of a tool does not mean that the tool is BROKEN"

For creating the Press Page images the cam is blind to many of the most basic forms of life.

Originally posted by ArchAngel
"Yes, but I say again... poor use of a tool does not mean that the tool is BROKEN"

For creating the Press Page images the cam is blind to many of the most basic forms of life.

Do you not consider chlorophyll A to be an indicator of many of the most basic forms of life?

Why do you seem fixated on only one of the two response peaks for one type of chlorophyll, and ignore that three of those four peaks are REMARKABLY well-detected?

Why act as if the press-release combinations are the only way to detect life... even life that might have chlorophyll B in it (and from your argument, I guess all Martian life must be composed of nothing BUT exclusively chlorophyll B)?

Do you think that the methods the team chose to use are the ONLY method possible for creating press release images, if they were focused on trying to show pictures of chlorophll-laden objects?

I keep mentioning that a tool is not to blame for the poor results when it is mis-used... do you understand what that means?


[Edited on 2-14-2004 by BarryKearns]

Why do you seem fixated on only one of the two response peaks for one type of chlorophyll, and ignore that three of those four peaks are REMARKABLY well-detected?

Some life only has chlorophyll B. It looks orange to the cam with either L256, or L456.

Chlorophyll a becomes orange when you use L256.

Originally posted by ArchAngel

Why do you seem fixated on only one of the two response peaks for one type of chlorophyll, and ignore that three of those four peaks are REMARKABLY well-detected?

Some life only has chlorophyll B. It looks orange to the cam with either L256, or L456.

Chlorophyll a becomes orange when you use L256.

Brilliant. So if it can't detect ALL POSSIBLE LIFE FORMS in any given presentation form, it must be "life-blind", right?