Spiral versus Ellipse in Virgo

[Placidus]

Quite a contrast. The beautiful grand design half-face-on spiral with tightly wound arms at top left is NGC 5364. It has a pin-point core.

The very unusual orange-coloured elliptical at top right is NGC 5363. Close inspection shows fine branching dust-lanes, suggesting it has been munching on a spiral not so long ago. It seems to have three nuclei.

The thumbnail is a crop. The full image (https://photos.smugmug.com/Category/Astrophotography-at-Placidus/i-Vx3Pjdm/0/6365fb92/O/Virgo%20Quartet%20NGC%205364%20et%2 0al.jpg) is 30 min arc across, 0.55 sec arc/pixel, showing another beautiful yellow near-edge-on spiral at bottom right, and at least 50 other galaxies in the far distance.

L 7.5 hrs, RGB 1.5 hrs each, all in 30 min subs. Aspen CG16M on 20" PlaneWave on MI-750 fork.

Acquisition and processing with our own Selene and GoodLook 64.

[Bassnut]

Sharp and clean Mike, soo many galaxys.

[Slawomir]

Really beautiful image M&T.

One can even get an impression of the spiral galaxy being younger and vibrant, spinning happily through space, while the elliptical, aged, experienced, watching from a distance and slowly munching on a TimTam...

There is also an interesting apparently small object near the bottom of the image at around 5.30 o'clock - perhaps colliding galaxies :question:

[billdan]

Lovely image M&T, great colours in the spiral galaxy, all that action in 30 arcmins, just amazing.

Bill

[strongmanmike]

Out at my Observatory, so only looking at this on my cheap'ol Samsung Galaxy mob phone :sadeyes:....but I can tell this is a lovely image guys :thumbsup: Ill be honset, the dotty dec/wavelettonised detail in the spiral is juuust noticable but otherwise, lovely processing and great contrast between the galaxy morphologies, can't wait to have a really good look on a proper screen tomorrow, the fine dust lane in the Eliptical looks great and interesting :thumbsup:

Oh and thanks for not posting yet another Fighting Dragons image :scared:
:lol:...I do like a nice Dragon, buuut.....:scared2:
Mike

[gregbradley]

Wow, that is really nice. I imaged that one a while ago and loved its form.

That's one of your best. Love it. Fabulous colour and to get that fine dust in the elliptical is the icing on the cake.

Greg.

[Placidus]

Thanks, Fred. Not as many galaxies per field as around Grus perhaps, but lots and lots.



Thanks Suavi. We enjoyed the poetry most apt. The little fellow at 5:30 is quite blue. We wondered (with little basis other than colour and lack of clear shape) if it was an irregular dwarf.



Thanks Bill. It was a bit of a squeeze getting the four main galaxies in the field, but the contrast was very tempting.



Thanks Mike! Very glad you like it. We promise to keep away from that bit of Ara this season.



Thanks for the very welcome encouragement, Greg. We'd love to know more about that elliptical.

Very best,
M & T

[marc4darkskies]

Very beautiful image M&T! :thumbsup: I love galaxy groups and this one is a cracker!

Faint vertical bands across the frame though - some camera artefacts? Also a bit of a green cast going on - bottom left especially.

[strongmanmike]

Still on the mob phone out here...but gee, Im really enjoyin this one, come back to it a couple'a times, a great grouping.

Mike

[cometcatcher]

A beautiful pair that's for sure. Wonderful image.

[Atmos]

Really nice shot you've got there. It kinda has everything, young galaxies, old galaxies, active and "dead" galaxies :)

[RickS]

Lovely image, M&T :thumbsup: Some very photogenic galaxies of all (apparent) sizes.

Astroplanner claims these galaxies are actually in Hercules?

Cheers,
Rick.

[Placidus]

Thanks Marcus. The banding is patterned readout noise. It would go away if we did many more hours. We can also process it out. Will revisit.



Thanks Mike, we're much encouraged.



Thanks, Kevin!



Cheers, Colin. A nice description.



Hi, Rick. Thanks for spotting that. Mike's bad typing. The NGC numbers were out by 1000. This is now fixed in the original post, so they are now safely back in northern Virgo.

Best,
Mike and Trish

[RickS]

Thanks, I'm sure they'll be much happier there :lol:

[Retrograde]

Another cracking image M & T. Gives me a real 'floating in intergalactic space' feeling.

[Paul Haese]

Nice field of view Mike. Colour is superb and the detail is excellent. A very nice image.

[strongmanmike]

Ok looking at it on the proper screen at home now and yep still an awesome field, the good thing about a genuinely big scope, always has that much more grandeur about it, great colours in the galaxies too. I love those faint curved arms extending off the ends of the edge on spiral just above the blue star lower left :thumbsup: I can see the warts Marcus referred to, they were not noticeably on the mobile phone screen last night and the uniform dot like decon/wavelettes detail is more noticeable in the spiral too, still a very pleasurable view though and I enjoyed viewing it out under the stars last night too :thumbsup:

Mike

[Placidus]

Here is a link to the Answer in the Back of the Book (https://www.noao.edu/image_gallery/html/im1130.html). A big mosaic using the NOAO Kitt Peak 4 metre scope. They have a 10 MB version (https://www.noao.edu/image_gallery/images/d7/ngc5364.jpg).

NOAO says that the two galaxies are starting to interact gravitationally.



Thanks, Pete.



Thanks, Paul. The NOAO image looks distinctly, perhaps implausibly, redder than ours, but they are using B, G, and I filters.



Thanks, Mike. I think I misunderstood which vertical banding Marcus was referring to. There is some faint fat banding which is camera noise. There are also a large number of very fine not-quite-vertical lines, which are courtesy of Qantas. They seemed to keep adjusting the flight path to follow our scope. There were so many that the usual statistical outlier rejection did not completely get rid of them. Luckily this is not normally a problem.

We were rather delighted to see that comparing back to back with the 4 metre scope, we didn't come out too shabbily.

Many of the intense blue dot-like star-forming regions in the spiral arms in our image resolve in their image into several smaller sub-dots, but the dots are in the right place. The dust lanes in the elliptical match up nicely too.

What they do have is hugely more resolvable background galaxies, which in our image just look like stars.

Very best,
M

[Andy01]

I'm enjoying seeing the contrasting galaxy types, but compositionally I'm struggling with this image.
Mabye it's just me but my eye keeps darting about from side to side, up and down with no particular point of focus or "hero" to on which to rest.
Neverless, the colours and details are very cool. :thumbsup:

[strongmanmike]

Oh I am sure your image compares very nicely to that big'ol 4m, it's beautiful :thumbsup:

I think the problem with decon/wavelettes filters is that both can easily force all the HII and star cluster details (in the case of galaxies) into uniformly round dots and it is this effect that my eyes are so highly tuned :face: to notice....it just doesn't look real to me :shrug:

Mike

[Placidus]

That's clealy put, Mike. I think I understand better now. When used even more recklessly, wavelet sharpening and decon in particular can produce what I call a "glassy" look - high contrast but nothing to do with what's up there. We try to stop short of that, because it's pretty ugly. But I think you're saying, quite reasonably, that one should stop even further short.

Is it possible to use subtle sharpening or local contrast enhancement without either putting things in the image that aren't in the sky, or taking out of the image things that are really there?

MBJ

[Geoff45]

Beautiful field there Mike and Trish. Regarding decon. My test for the right amount of decon is that Mike S fails to comment on it.

[traveller]

Beautiful shot M&T. Plenty of background galaxies to keep the viewer engaged.
Bo

[DJT]

A lovely image MnT. I enjoyed swimming around in the large version, so many galaxies, with the two stars being standouts in terms of details.

Well done!

[strongmanmike]

:lol:...oh well, we do see less worms and dots these days...:face:

Seriously though, there was a time I recall a fixation on noise levels in images being pointed out in every post reply...but noise is not an intentionally added applied option but rather a function of less than optimal exposure time or over stretching, so IMO at least...it is much less of a processing crime :eyepop:. However, (over) applying a filter to artificially alter the details and completely changing the look of an image, well!..THAT is a serious crime...that needs reporting to the correct authorities! :mad2:

:rofl:

[SimmoW]

Wow a really deep image chock full of activity M&T.

I'd call your pic more of an 'Avengers' shot, no single hero in this baby. Love that elliptical, the dust lane teasing the eyes, is it really there? Yes it is!

With all the mosaics out there, why not make it even bigger, do an Avengers versus Justice League battle scene... make me chuckle 'this is a 4 by 4 panel mosaic comprising 23 arcsecs' :lol: :lol:

[Placidus]

Thanks Geoff.



Cheers, Bo. Glad you like it.



Thank you David!



We shall be ever more gentle.



Thanks Simmo.

Best,
Steed and Emma.

[SimmoW]

Haha, oh Diana Rigg, what a class act!