Macros

Discussion in 'Photography' started by Alan Browne, Mar 16, 2013.

1. PeterNGuest

Ah! but are the gravitational fields random. According to Einstein, they
are not.

PeterN, May 3, 2013

2. Wolfgang WeisselbergGuest

So you're basically saying that the gravitational fields are
ordered in such a way that photons from any random source stay
parallel, at least in a sizeable number of cases.

I'd like a single geometry designed by you where a bundle
of parallel light rays from a single direction are bend by
gravity sources in such a way that they remain exactly parallel.
You can freely place the gravity sources.

Kindly remember that any single gravity source will affect such
a bundle of exactly parallel rays differently, depending on the
mass of the gravity source and the (different!) distance from
the individual ray to the gravity source. In other words:
a bunch of parallel rays *will* be spread when it passes a
gravity source ...

Too hard?

-Wolfgang

Wolfgang Weisselberg, May 6, 2013

3. PeterNGuest

I I precisely understood how gravitational forces interact, I doubt I
would waste time responding to you.

PeterN, May 8, 2013
4. Martin BrownGuest

Trouble is that stars for the most part tend to be heavily concentrated
in galaxies, cluster of galaxies and super clusters of clusters.

The net result is that you can get strong lensing effects of very
distant sources by galaxies or clusters between us and the source.
Einstein rings were predicted long before they were observed.

http://hubblesite.org/hubble_discov...nstein_rings_natures_gravitational_lenses.pdf

Probably by far the prettiest one is the Hubble image of the horseshoe
ring around LRG 3-757 (sorry about the unromantic name for the latter)

http://nasa-image.blogspot.co.uk/2011/12/horseshoe-einstein-ring-from-hubble.html

That said most of the light rays from distant sources to an exceedingly
good approximation do remain parallel.

Martin Brown, May 8, 2013
5. J. ClarkeGuest

It's not a matter of "approval", it's a matter of soliciting the advice
of others to improve your own work. You're not obligated to take that

J. Clarke, May 8, 2013
6. Wolfgang WeisselbergGuest

If you precisely understood how gravitational forces
(and matter and space) interacts, you'd probably on the list
for the Nobel price.

If you "merely"[1] had a working understanding of how
gravitatonal forces act *and what that means* you'd be more
careful about "in such a way that photons from any random
source stay parallel", e.g. by making clear that they probably
won't stay perfectly parallel. ('probably' only because I
cannot guarantee that there can't be a setup where they *do*
stay parallel.)

-Wolfgang

[1] not that that is something small in any way

Wolfgang Weisselberg, May 8, 2013
7. Wolfgang WeisselbergGuest

And that *keeps* the rays *parallel*?

Yep, but the rays aren't parallel --- can't be, otherwise
they must look like they came from the very same point (due
to the distances involved).
Only for distances that are very short compared to the distance
from where they come.

But we were getting theoretical, not real-world 'close enough'.

-Wolfgang

Wolfgang Weisselberg, May 8, 2013
8. PeterNGuest

Spot on. Many photographic masterpieces, would not score well in CC
competitions. There are members who prepare images solely for CC
competitions. If that is what they want, than I say fine, but as you
correctly point out, there's a lot more to camera clubs than just
competitions. Here is an image that I like, but did not do well in CC
competition. But, I still like it.

<https://dl.dropboxusercontent.com/u/97242118/swooper.jpg>

PeterN, May 8, 2013
9. PeterNGuest

But the origins of the gravitational are not random. You certainly are
free to speculate what would happen if they were, but I would rather
concentrate on the far less esoteric topic, of how to improve my images.

PeterN, May 9, 2013
10. Wolfgang WeisselbergGuest

Did I get that right? You're basically saying that the
objects are both random and not random?

-Wolfgang

Wolfgang Weisselberg, May 11, 2013
11. PeterNGuest

PeterN, May 11, 2013
12. Wolfgang WeisselbergGuest

it as meaning "the gravitational influence/the gravitational
objects", because *that* makes sense, while "the gravitational"
does not, at least with my very limited knowledge of English ...

-Wolfgang

Wolfgang Weisselberg, May 13, 2013
13. PeterNGuest

IF the objects were truly random, ......
Then I said but, the objects are not random. Nothing contradictory
there. But yes I should have said the origins of the gravitational
fields are not random. I hope this clarifies.

BTW the authority for my statement is Einstein, and that is what I
remember him telling me. Since I was only about 11 at the time, I might
have misunderstood.

PeterN, May 14, 2013
14. Wolfgang WeisselbergGuest

You started to talk about "theoretical" and "randomly
distributed objects". Then you say "but they [the
theoretical randomly distributed objects] are not random".
Ok, the objects are not random, so your "If you want to get
theoretical" claim has been abandoned as indefensible.

So please construct a non-random arrangement of objects that
do keep the rays in parallel as they pass through it. Have fun!
Which statement? That "randomly distributed objects might
very well equalize each other"? That "Therefore the rays would
remain parallel"? That "the origins of the gravitational are
not random"? That you are not contradicting yourself?

-Wolfgang

Wolfgang Weisselberg, May 14, 2013
15. PeterNGuest

PeterN, May 15, 2013
16. Wolfgang WeisselbergGuest

[PeterN moved the goalposts and can't even tell us which
statement he claimed he had heard from Einstein himself]
Sour grapes, Peter? Very sour grapes, eh?

-Wolfgang

Wolfgang Weisselberg, May 16, 2013
17. PeterNGuest

No just not replying to troll questions.

PeterN, May 18, 2013
18. Wolfgang WeisselbergGuest

Yep, asking you what exactly Einstein told you is a troll
question *and* an insult.

But still, I'd like a configuration where gravity sources
(carefully placed by you) do *not* influence parallel light
rays to become non-parallel.

-Wolfgang

Wolfgang Weisselberg, May 20, 2013
19. J. ClarkeGuest

Wolfgang, I really do not understand why you are harping on this ad-
nauseum. If you think it has some real relevance to the issue of
starlight being treated as parallel rays then do explain the relevance.

J. Clarke, May 21, 2013
20. PeterNGuest

Go back and read. If you don't believe me, that is your problem.

I didn't say that in a random configuration that would be no influence.
I said there could be offsetting influences. But we already went that
route.

PeterN, May 21, 2013