best of Hubble images

In article , says...
"Paul Furman" wrote
Isn't that the result of terrestrial versus space based observing?

They are a pastiche of IR and visible images, taken with very narrow
band filters, false colored, hand-masked with lots of local contrast
adjustment, and then reassembled.

They have a technique that makes wisps of hydrogen gas
look like a solid cloud reflecting starlight from some off-camera
source. There is no off-camera source and the brightest parts
of the cloud in the manipulated image are the dim outer bits
in a more realistic view.

NASA has made V838 Monocerotis, where the gas is 'illuminated'
(the light source that makes it glow) is inside the ball
... http://www.noao.edu/outreach/aop/obs...8monharris.jpg
in real life ... look like a red (and just where did that shade of red come
from?) star peaking out from a rupturing solid sphere.
http://www.nasa.gov/images/content/1...84_946x710.jpg
where the 'surrounding' stars are brightly lighting up the sphere. There
are no surrounding stars.

Naw, it's the other end of the horse that fits this image.

But the heavy handed manipulation does wonders for funding. Who
wants to look at another dim purple wisp?

I think that is a little unfair. If you compare the two V838 Monocerotis images, it is clear that the nasa one is
showing features that are completely invisible in the noao image. The "bright" part of the cloud in the lower
resolution image has been supressed in the high res image to reveal structure closer to the central star. The structure
has not been 'invented' by a graphics artist - it is there and is real and the details provide useful information on
the dynamics of the system to astronomers and astrophysicists.

To claim the manipulation is heavy-handed is absurd. It would be equivalent to claiming that the false-colour
microwave-background-of-the-universe images are bogus because "Like, we can't see microwaves so the image should be
black, Dude". The nasa view is a 'map', showing the distribution of specific elements in specific electronic and
thermal states and as such is a useful tool. Incidentally, it is also an attractive image to my eye.

Mike

In article , says...
"Paul Furman" wrote
Oh well, I suppose it's rationalized as enhancing for better scientific
inspection.

Why do things have to be 'scientifically rationalized'?

Apart from being an oxymoron.

The purpose of 'science' is to explain what already is, without making
any judgement of value.

That it provide better bread and circus is the only
justification needed.

Painting in V838 makes for better circus, and better circus gets
congress to give NASA more bread. That colorizing job doesn't
contribute to understanding any more than solarizing a nude
study would bring.

To reiterate, the image you complained of, was showing structure invisible in the original. By way of comparison, look
at the difference between the previous two images and http://apod.nasa.gov/apod/ap040305.html which is closer to a
simple 'optical enhancement' of the low res image.

Mike

"Mike" wrote

To reiterate, the image you complained of

Mike, you seem to be the only one 'complaining'. If
you find my viewpoint reprehensible just drop my in your
kill file.

Try stating your _own_ viewpoint with out reference to
someone else's. Neither I, nor I imagine any other
readers, are interested in this sort of banter - especially
so when it is 'reiterated'.

--
Nicholas O. Lindan, Cleveland, Ohio
Darkroom Automation: F-Stop Timers, Enlarging Meters
http://www.darkroomautomation.com/index.htm
n o lindan at ix dot netcom dot com

Craig wrote:
On Tue, 26 Feb 2008 06:34:47 -0600, Ron Hunter wrote:

Troy Piggins wrote:
* Ron Hunter :
Troy Piggins wrote:
* Paul Furman :
http://www.dailymail.co.uk/pages/gal...n_page_id=1055
Not Hubble images, but check out some of this guy's photos. He
attaches his 20D to a telescope mount.

http://photography-on-the.net/forum/...d.php?t=450144
http://photography-on-the.net/forum/...d.php?t=450156
http://photography-on-the.net/forum/...d.php?t=419180
http://photography-on-the.net/forum/...d.php?t=451640

Amazing.
Nice images. Would like to know what kind of telescope he was using.
I think he usually posts details of what he took them with just
above the images. Doesn't he?

Only the camera information.

No, he also posts the Scope and Mount. He is using a 90mm Takahashi
Refractor on a Losmandy G-11 mount. he scope is around $2k and the mount
around $3200.

Thanks. For exposures of the length he mentions, a good mount would be
essential. Really pretty impressive pictures considering the equipment
used.

On Feb 27, 3:31 am, "Nicholas O. Lindan" wrote:

Neither I, nor I imagine any other
readers, are interested in this sort of banter - especially
so when it is 'reiterated'.

I, for one, found his posts in this thread to be well-thought out,
reasonable, informed and on topic, and also quite interesting.

On Tue, 26 Feb 2008 21:17:28 -0500, Pudentame wrote:

Nicholas O. Lindan wrote:
There seems to be lot of 'illumination' in these pictures
(i.e. - an awful lot of photoshopping).

You wouldn't think the Triffid shown here
http://img.dailymail.co.uk/img/galle...10_350x301.jpg

Has much in common with these other Triffids -
http://www.world-mysteries.com/mpl_p...bula_nasa1.jpg
http://www.cuyastro.org/images/cukras-triffid-full.jpg

At least the sombrero retains a bit of resemblance to its 'before' image:
Befo
http://photos.crosscountryadventures...ro360425es.jpg
After: http://img.dailymail.co.uk/img/galle...O1_350x175.jpg

I doubt NASA uses anything as mundane as Photoshop for the Hubble images.

What you're seeing is the difference in the resolving power of different
telescopes and the camera's attached to them.

Hubble vs. large ground based observatory (e.g. Hale or Keck ...) vs.
amateur astronomer w/DSLR.

Actually no. NASA uses PS as wellas a lot of custom image processing SW. As
for showing the differences, I'm going to point you to some hubble vs
Amateur mars shots for comparison. Also the 60yr old Hale telescope
recently (last year) produced the sharpest astro photo ever (besting Hubble
and Keck etc...) through the use of Adaptive optics.

http://www.digitalsky.org.uk/mars/20...Hubble-pbl.jpg

http://www.news.com/Lucky-camera-boo...3-6205940.html

http://www.accessmylibrary.com/coms2...6-33247391_ITM

On Tue, 26 Feb 2008 20:47:52 -0500, Pudentame wrote:

Nicholas O. Lindan wrote:
"Troy Piggins" wrote
http://photography-on-the.net/forum/...d.php?t=450144
http://photography-on-the.net/forum/...d.php?t=450156
http://photography-on-the.net/forum/...d.php?t=419180
http://photography-on-the.net/forum/...d.php?t=451640

Not bad. All taken with a 500mm f8 Apo-doublet:
http://www.adorama.com/TKTSK9001.htm...39901721249430


Why would it be f/8 instead of f/5.6?

It looks like Tak sells an F/8 and F/5.6. Based on other images he posted
It looks like he as the F/8 and a 1.6 focal reducer-corrector bringing the
effective F/ratio to 4.5.


When used for birds ...
http://www.anacortestelescope.com/ga...otos/14316.jpg

In full regalia:
http://www.anacortestelescope.com/product.asp?pid=1980

Craig wrote:
Also the 60yr old Hale telescope
recently (last year) produced the sharpest astro photo ever (besting Hubble
and Keck etc...) through the use of Adaptive optics.

Couldn't they use the same technology on hubble & do even better?

http://www.digitalsky.org.uk/mars/20...Hubble-pbl.jpg

http://www.news.com/Lucky-camera-boo...3-6205940.html

http://www.accessmylibrary.com/coms2...6-33247391_ITM

On Feb 27, 1:56*pm, Paul Furman wrote:
Craig wrote:
Also the 60yr old Hale telescope
recently (last year) produced the sharpest astro photo ever (besting Hubble
and Keck etc...) through the use of Adaptive optics.

Couldn't they use the same technology on hubble & do even better?

The main purpose of adaptive optics is to cancel out atmospheric
disturbances. Since Hubble is outside the atmosphere to begin with,
adaptive optics wouldn't help much.

Hubble's primary mirror is 2.4 meters, which is fairly small by
current land based standards. What you want to do is put a 6 to 10
meter telescope in orbit. Then you'll get some images to write home
about.

In message , Paul
Furman writes
Craig wrote:
Also the 60yr old Hale telescope
recently (last year) produced the sharpest astro photo ever (besting Hubble
and Keck etc...) through the use of Adaptive optics.

Couldn't they use the same technology on hubble & do even better?

No. The Hubble is truly diffraction limited but of very modest finite
aperture (small by comparison to many ground based scopes). But it is in
orbit so isn't affected at all by atmospheric seeing. You are lucky to
get below 1" arc resolution in a time exposure from a ground based
scope.

All ground based scopes suffer this affliction of seeing through
turbulent air thermals. Adaptive optics correction is only really useful
for larger ground based scopes (roughly 1m class and above). Although
tip-tilt correctors are now available to amateurs on more modest
apertures.

http://www.digitalsky.org.uk/mars/20...Hubble-pbl.jpg

http://www.news.com/Lucky-camera-boo...1397_3-6205940.
html
http://www.accessmylibrary.com/coms2...6-33247391_ITM

Some amateur folk with webcams, larger scopes and stacking software are
getting pretty close to Hubble quality images of the brighter planets
these days by sifting through thousands of short exposures for the
handful of lucky ones.

Regards,
--
Martin Brown

--
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