And now for something completely different - the moon 11 march

[h0ughy]

I have on offer here two versions - the first is a 8 panel version using the DMK51 at prime with the ed127, the second is with the DMK51 and a 2.4 vixen barlow lens also on the 127ed- unfortunately the conditions deteriorated but it did make a 4000+ pixel image - unfortunately i put a 1024 version here

EDIT added a repro of the 8 panel version?

[pw]

First one looks crispy and detailed.

[RB]

A bit too dark for my liking Davo.
My aging eyes, you know......:P

[h0ughy]

yep the seeing was kind - it went on the boil after those:sadeyes:

[h0ughy]

sorry:shrug::help:

[strongmanmike]

Ahhh..?...The Moon... :zzz2:

:lol: ok, ok, sorry but I am only in Yr10 Physics remember, since I haven't photographed the moon in anywhere near this level of detail that was me trying desperately to make carefully constructed sarcasm and a cheeky comment to prevent you from seeing the real person in desperation of approval :sadeyes:

Seriously, I recon that's a great moon mozaic and yeah perhaps a tad dark but it looks like something from a movie , nice.

Mike

[h0ughy]

mmmm godzilla verses bambi eh?

the dynamic range killed it for me getting it brighter , the bright hotspots in the craters are bad enough now let alone when they bloom:P

I did try it for a trial and some hope of entering a certain competition but there is no way its good enough for that - toilet door maybe:thumbsup:

[alan meehan]

Dark but detailed Dave

[h0ughy]

In defence of the image - I deliberately didn’t set out to make it overly over processed. Instead I was trying to get a representation of the Albedo: from wikipaedia




Astronomical albedo[edit]The albedos of planets, satellites and asteroids can be used to infer much about their properties. The study of albedos, their dependence on wavelength, lighting angle ("phase angle"), and variation in time comprises a major part of the astronomical field of photometry. For small and far objects that cannot be resolved by telescopes, much of what we know comes from the study of their albedos. For example, the absolute albedo can indicate the surface ice content of outer Solar System objects, the variation of albedo with phase angle gives information about regolith properties, whereas unusually high radar albedo is indicative of high metal content in asteroids.

Enceladus, a moon of Saturn, has one of the highest known albedos of any body in the Solar System, with 99% of EM radiation reflected. Another notable high-albedo body is Eris, with an albedo of 0.96.[14] Many small objects in the outer Solar System[15] and asteroid belt have low albedos down to about 0.05.[16] A typical comet nucleus has an albedo of 0.04.[17] Such a dark surface is thought to be indicative of a primitive and heavily space weathered surface containing some organic compounds.

The overall albedo of the Moon is around 0.12, but it is strongly directional and non-Lambertian, displaying also a strong opposition effect.[18] Although such reflectance properties are different from those of any terrestrial terrains, they are typical of the regolith surfaces of airless Solar System bodies.

Two common albedos that are used in astronomy are the (V-band) geometric albedo (measuring brightness when illumination comes from directly behind the observer) and the Bond albedo (measuring total proportion of electromagnetic energy reflected). Their values can differ significantly, which is a common source of confusion.

In detailed studies, the directional reflectance properties of astronomical bodies are often expressed in terms of the five Hapke parameters which semi-empirically describe the variation of albedo with phase angle, including a characterization of the opposition effect of regolith surfaces.

[Varangian]

Moody moon - I like it!

[h0ughy]

thanks John - its not the norm

[h0ughy]

added a Sidonio (http://www.iceinspace.com.au/forum/attachment_browse.php?a=158650)

[Dennis]

Nice work David – beautiful detail and clarity. How many panes did you knit together in the x2.4 Barlow image?

Cheers

Dennis

[h0ughy]

32 panels Dennis, they started sharp then went to gooop as the next hour went on:sadeyes:

[Dennis]

Thanks Dave – that requires a lot of stamina and dedication to do that, not to mention the post capture processing and integration.:)

A truly herculean task, I admire your perseverance.:thumbsup:

Cheers

Dennis

PS – I’ll have a peek at the file you sent when the rellies have gone.:)

[Dennis]

Hi David

This is the best that I could do, in trying to lighten the overall tones. There is much posterisation in the dark regions, especially near the terminator.

Nice data set though!:)

Cheers

Dennis

[h0ughy]

i think it came down to the overall camera setting i maintained throughout the whole run. next time i will lighten it up at the risk of blowing out some areas:thanx:

[Dennis]

Hi David

For a single frame, I have found that looking at the histogram to keep the whites just below 100% (255) usually works for the extended brighter areas such as Tycho and Aristarchus. For the smaller bright craterlets or other small bright features, I don’t mind blowing them out in order to rescue detail in the darker parts of the image.

Of course this is fine on a single frame, but when you are trying to maintain consistency over 32 frames for a mosaic, this may require some frames to be exposed twice; once for the highlights and then for the darks so they can be stacked in PS.

Cheers

Dennis

[iceman]

Really nice Dave. Definitely a bit dark but sharp and moody :)