Ngc300

[Shiraz]

Hi

Have had pretty bright skies over the last month, but finally got some that was dark enough to find some detail in NGC300. I was initially concerned by the noisiness of the image, but part of the problem seems to be that the galaxy is close enough to resolve some finer detail and this looks grainy - at least that is my excuse....

Could have done with a bit of Ha to bring out the star formation regions, but I have already spent enough (often fruitless) time pursuing this galaxy - next time maybe.

Thanks for looking. Regards Ray

GSO 200mm F4 with RCC1
SX HR694
NEQ6
cropped and downsized x0.8 to fit

[strongmanmike]

Wow look at all those details :cheers: yep at 20' across it's a big close face on galaxy so you can sure resolve some stars in there :thumbsup: Excellent balance but a minor point does it look a tad bichrome? (Yellow and cyan/blue) ...maybe, so I agree some Ha may well have added something. Never the less a magnificent version of this galaxy...probably the best posted on here this season too :)

MIke

[Larryp]

Very nice!

[naskies]

That's a great looking galaxy there, Ray!

[Shiraz]

Sprung.. The attached image is how it came out of the processing with no messing with the colour - I tried to be smart and push the blue a bit to enhance the bright regions and compensate for galactic extinction. Thanks for the feedback Mike


Thanks Laurie

regards Ray

[Shiraz]

Thanks Dave regards ray

[tilbrook@rbe.ne]

Outstanding Ray!:thumbsup:

Glorious feast for the eyes, nicely balanced and detailed.

Between you Mike and David with his Bunyip we are spoiled on this forum!!

Cheers,

Justin.

[strongmanmike]

No I prefer the first version...you should consider getting back out for just some Ha, can do it from the city too, say 2hr of Ha then blend it into the Red and recombine...that's what I would do anyway :P..thne again, perhaps there is little Ha in NGC 300 :question:

Mike

[Shiraz]

yep, you are right :thumbsup: - I will get some Ha and do it properly, like I should have done in the first place. There are definitely some Ha regions in there.

[Shiraz]

thanks Justin. very generous comment that is appreciated. regards ray

[astronobob]

A mighty nice looking result Ray, Tight stars and detail, wow. I prefere your 1st Rendition also :thumbsup: I know nothing about narrowbands etc, but looking forward to the Ha added if you get to, extra cool !

[gregbradley]

Oh wow. That took my breath away. That is a stunning NGC300. That is really an amazing result from an 8 inch GSO Newt. Unbelievable.

Greg.

[gregbradley]

Arrrgghhh tread carefully there! I would not blend Ha into the red channel as you lose control. Ha will dominate and you'll get one of those silly M33 with pink splotches everywhere! Lightly does it and Ha as a separate layer in lighten mode so you retain control.

You've got a masterpiece galaxy image here so don't spoil it!
Greg.

[RickS]

A lovely NGC300, Ray! What were your integration times?

[pluto]

That's an excellent image, thanks for sharing :)

[marc4darkskies]

Nicely done Ray - some great detail in there!

Cheers, Marcus

[Paul Haese]

Yep better than my effort Ray. Though you are using 4 more inches than I am at present. I like the detail and the image scale. Well done.

[Lee]

Lovely work Ray... love the negative version....

[Shiraz]

Hi Bob - thanks


Hi Greg - thanks for the comment. At 8 inch aperure, the atmosphere dominates and optics become less important. The biggest issue with the GSO was getting the mechanical system sorted - everything bends slightly.


thanks Greg - yes, there is always the risk of stuffing it up - will be careful :)


Thanks Rick. about 3.5 hours lum, about 5 hours RGB total all at 1.17 arc sec (1x1), 200 sec. will go back and check exactly how much in each colour, but red was the problem child due to sodium light pollution and it required a lot of time.


thank you Hugh - it is great to have something to post


Thanks Marcus


thanks Paul. aperture sure helps, but the biggest problem was getting enough good seeing in combination with dark skies. I am going to have to find a better dark site than this one if I am going to image this sort of stuff.


Thanks Lee. I like the negative version as well - somehow we seem to be able to see detail better when it is reversed - don't know why

Regards Ray

[Lee]

I think you can stretch more and increase the contrast before it becomes undesirably clipped.... ??

[Peter.M]

That's what she said

I couldn't help myself. Great image of a great target!

[PRejto]

That's a cracker of an image!! I tried this a year ago but from light polluted Sydney I think it was a lost cause before I started.

I'll be curious to see the Ha blend when and if.

Peter

[naskies]

I was thinking about this today on my way to/from classes today, and remembered that I'd read about it during my visual system module at uni last year.

The short answer is that it's physiologically wired into our retinas.

Our retinas have separate and different circuits, retinal ganglion cells, for detecting a "white dot on black background" (so-called ON retinal ganglion cells) versus a "black dot on white background" (OFF cells). The photosensitive rods and cones that we all know about feed their output (eventually) to the retinal ganglion cells.

It sounds a bit absurd, but the different types of cells are used to detect object edges - see the red/green computer simulation diagram at the bottom:

http://en.wikipedia.org/wiki/Receptive_field

When viewing low contrast scenes, ON cells can detect both decreasing light ("grey dot on black background" turns into a "white dot on black background") and increasing light ("black dot on a white background" becomes "grey dot on a white background") changes. However, OFF cells can only detect decreasing changes in contrast.

Therefore, with low-contrast images - looking at faint structures in astro images - our eyes are more sensitive to light decrements (i.e. black detail on a white background as with inverted astro images) because both the ON and OFF pathways are triggered.

Here's an article that describes the technical detail behind the mechanisms (warning: it's not an accessible read for non-physiologists), but receptive fields in general are discussed in most vision texts.

http://www.jneurosci.org/content/23/7/2645.full.pdf

[Paul Haese]

Yeah it took me a few years to find my spot.

[strongmanmike]

Oi! what's wrong with red splodges :mad2: :shrug:...some people love'em :D

Don't listen to him Ray dooooon't.. get out there blend, BLEND BLEND I say! :rofl:

Mike

[Nicola]

Excellent details! :thumbsup:

[Shiraz]

will have a play around and post a revised version if I can do any better.


:lol: thanks Peter


Thanks Peter. It is pretty hard imaging faint objects in light pollution - can't imagine what it must be like in Sydney


Thanks very much for that Dave - very clear explanation. So there is a physiological basis for our ability to see dark detail against a light background - fascinating. Now for an hypothesis on why. Maybe our eyes have the same structure as those of smaller creatures that had a need to see predatory birds against the bright sky. I was watching Meerkats at the zoo and they maintain a constant watch on the sky responding to birds and aircraft with alarm. Physics dictates that most objects at a distance end up as dark spots against a bright sky and mammalian visual systems have evolved to be very sensitive to that threat - maybe?.


It was OK over here, but then Viterra decided that the whole town needed to be able to bask in the glow of the floodlighting on their silos and the local council decided that the hospital helipad needed Sodium lighting that burned off the surrounding grass as part of its task.


Two experts with differing opinions - unprecedented :P. Probably will tread warily until I get a better understanding of what I am trying to do



thank you Nicola

[Rigel003]

Fantastic photo of a magnificent galaxy, Ray. It's like a southern version of M101. Just beautiful.

[Shiraz]

thanks very much Graeme Regards ray

[multiweb]

Superb shot Ray. Missed that one. Shows me what can be done with that scope. Pretty high standard. :thumbsup:

[jjjnettie]

Beautiful!

[Shiraz]

thanks Marc. The scopes are pretty good optically, but a real PITA to manage mechanically - everything bends and shifts a little.


Thanks very much Jeanette

regards ray

[Ross G]

Great looking photo Ray.

Sharp, detailed with great colour.

Nicely composed.

Probably the best photo I have seen of this galaxy.

Ross.

[Shiraz]

Hi Ross. thanks for your generous comment. Regards ray

[strongmanmike]

Yeah? well just you wait till he adds (oh, I mean blends) that Ha in Rossco! :cheers:

:P