New Moon pictures

On 3 Jun 2004 07:22:21 -0700, (andrea tasselli)
wrote:

Good question, in a way. I can offer this as an answer: a number of
people processed the same raw image of jupiter and came to extremely
close results. This is quite telling if one consider they used most
likely different software and different methods, all unknown to each
other. Note also that different people see the same scene noting
different details as well as different hues so there is no such a
thing as an "objective" reality. If anything a digital image is closer
to objectivity than is human vision.

Yes, but in order to use a digital image you have to look at
it--using your human train of responses.
How is looking at a digital image more objective than looking at
one formed by the eyepiece? Two people could look at the same
digital image and note different details just as in the eyepiece.
The periodic smearing of detail in the eyepiece that observers have to

put up with has nothing to do with subjectivity; it produces an image
as optically "real" as anything can be. And although far from
perfect, the human eye is as objective a camera as anything can be;
the subjective aspect is rooted in what the brain does to the
information, regardless of how optically aberrated it might be.


Dan

(Dan Chaffee) wrote in message ...
On 3 Jun 2004 07:22:21 -0700, (andrea tasselli)
wrote:

Good question, in a way. I can offer this as an answer: a number of
people processed the same raw image of jupiter and came to extremely
close results. This is quite telling if one consider they used most
likely different software and different methods, all unknown to each
other. Note also that different people see the same scene noting
different details as well as different hues so there is no such a
thing as an "objective" reality. If anything a digital image is closer
to objectivity than is human vision.

Yes, but in order to use a digital image you have to look at
it--using your human train of responses.

Yes, but you don't need to evaluate it by try to seeing fleeting
details, do you? Numbers are numbers and you can study a graph, if you
want.

How is looking at a digital image more objective than looking at
one formed by the eyepiece?

Size and time. An image is forever fixed by a given response to a
given stimulus. And you could allucinate while looking in the EP.
Remember Pickering?

Two people could look at the same
digital image and note different details just as in the eyepiece.

They may evaluate the aestetical value in a different way but they
could hardly disagree (apart from the method used to obtain it)
whether a given value is a given value.

The periodic smearing of detail in the eyepiece that observers have to

put up with has nothing to do with subjectivity; it produces an image
as optically "real" as anything can be.

Yes, as for being perceived as real (actually far more "real" than any
image) because is the subject that perceives it using his/her senses
without resorting to any other medium (other than the telescope, of
course).

And although far from
perfect, the human eye is as objective a camera as anything can be;

Not in the least. The human eye is frought with (not only with optical
distortions within it) false perceptions and wrong estimation of
brightness. This is in reality more due to processing the information
perceived within the eye-brain system but since we can't really
separate the two we'll have to accept it as part of "seeing" process.

the subjective aspect is rooted in what the brain does to the
information, regardless of how optically aberrated it might be.

You can't separate the two, can you?

Andrea T.

On 4 Jun 2004 07:21:15 -0700, (andrea tasselli)
wrote:

\
How is looking at a digital image more objective than looking at
one formed by the eyepiece?

Size and time. An image is forever fixed by a given response to a
given stimulus. And you could allucinate while looking in the EP.
Remember Pickering?

You can hallucinate while looking at _anything_, eyepiece or not.

Two people could look at the same
digital image and note different details just as in the eyepiece.

They may evaluate the aestetical value in a different way but they
could hardly disagree (apart from the method used to obtain it)
whether a given value is a given value.

They most certainly can dissagree on value. Having been a painter
over half my life and having taught drawing and painting, I have seen
example after example of students looking at the same photograph they
were copying and each showing a different sensitivity in duplicating
the relative shading and luminousity on the subject in the reference
photograph.

And although far from
perfect, the human eye is as objective a camera as anything can be;

Not in the least. The human eye is frought with (not only with optical
distortions within it) false perceptions and wrong estimation of
brightness.

So if we take a ccd using a telescope with 5 wavelengthes of
undercorrection and 2 waves of astigmatism, the image will be less
objective than with the unaberrated scope? Again, I'm talking about
objectivity here, not accuracy.

This is in reality more due to processing the information
perceived within the eye-brain system but since we can't really
separate the two we'll have to accept it as part of "seeing" process.

...My point.

the subjective aspect is rooted in what the brain does to the
information, regardless of how optically aberrated it might be.

You can't separate the two, can you?

In a sense, you can. When a representational artist converts what
he/she sees into pigment and values, the training process forces a
restructuring of the incoming visual information of a real scene or
setup to the extent that the end product is in fact so similar to a
photogragh that only careful inspection of brushtrokes can give away
the difference. If the eye-brain relationship were so restricted as
you suggest, this should not be possible. Most artists today are
incapable of such work (or simply couldn't care less) for a number of
reasons, but there are a few.

Dan