Just another face in the crowd ... Finished my Eta

[marc4darkskies (Marcus)]

Originally Posted by alpal

I often wondered how we should present H-Alpha information.

The logical choice is red but you could equally make it a white colour
as gray scale so that it looked like opaque clouds & it wouldn't be wrong -
since you can't see infra red anyway.

It gets down to personal choice.

I make it red. But I make sure it doesn't swamp other colour signal clearly present in the RGB. Personal choice has a lot to do with it but I think there's a baseline level of public "acceptance" as to what colours are best for an object. The trick is balancing the two!

Originally Posted by Leonardo70

Congratulation Marc....a perfect image !!!!



All the best,
Leo

Don't know about "perfect" but thank you Leo, much appreciated!

[alan meehan (Alan)]

Wow Marcus what a beautiful shot congrats on iotw well deserved,the best photo of eta i have seen.
AL

[marc4darkskies (Marcus)]

Originally Posted by alan meehan

Wow Marcus what a beautiful shot congrats on iotw well deserved,the best photo of eta i have seen.
AL

Thanks Alan - glad you think so!

[alpal]

Originally Posted by marc4darkskies

I make it red. But I make sure it doesn't swamp other colour signal clearly present in the RGB.
Personal choice has a lot to do with it but I think there's a baseline level
of public "acceptance" as to what colours are best for an object.
The trick is balancing the two!

Hi Marcus,
I agree with your philosophy however it has got me thinking as
to how your pic would look if all Ha data was presented
just as gray scale & mixed with the colour?

I will try that one day when I have a CCD camera & an Ha filter.
At the moment I'm not buying anything until
this weather pattern ends.

[Tandum (Robin)]

Originally Posted by alpal

Hi Marcus,
Ha data was presented
just as gray scale & mixed with the colour?

What ever your smoking, I want some

[alpal]

Originally Posted by Tandum

What ever your smoking, I want some

Hello -
Marcus writes of

public "acceptance" as to what colours are best

This is agreeing with me that my idea is not wrong
as we can't see Ha anyway.

[rally]

Alpal,

The Ha band is in the visible spectrum !

Is is bright enough to see ? - I guess that depends on aperture.

Rally

PS I think the image is in fact Ha in grey scale and mixed with colour
Its LHa RHa G B - I assume ?

[alpal]

Originally Posted by rally

Alpal,

The Ha band is in the visible spectrum !

Is is bright enough to see ? - I guess that depends on aperture.

Rally

PS I think the image is in fact Ha in grey scale and mixed with colour
Its LHa RHa G B - I assume ?

I would assume that too.
Did Marcus say if he took raw luminance - no filter?

[risingmoon (Sandra)]

The picture is so unbelievably beautiful

[marc4darkskies (Marcus)]

Originally Posted by alpal

...we can't see Ha anyway.

Ha will appear a dark red to the human eye (if intense enough to trigger the eye's L cones). Our eye isn't very sensitive to it but we can see it. It's frequency is near the peak transmission of most red filters so it's typically combined with the red channel. Dark red doesn't really display well on monitors either so you can lose the contrast inherent in Ha signal if you don't render it with a bit brighter red tone. Personal taste creeps in here of course.

Originally Posted by rally

...PS I think the image is in fact Ha in grey scale and mixed with colour
Its LHa RHa G B - I assume ?

Yes. L+Ha, R+Ha, G, B+Ha in fact

Originally Posted by alpal

I would assume that too.
Did Marcus say if he took raw luminance - no filter?

Luminance Filter

Originally Posted by risingmoon

The picture is so unbelievably beautiful

Thankyou Sandra! Always glad when folks enjoy one of my images!

[Peter Ward]

Originally Posted by alpal

............

as we can't see Ha anyway.

Beg to Differ.

It's exactly the same wavelength as viewed through countless (H-alpha) solar telescopes. Easy to see...(and very red ).

[alpal]

Marcus,

Ha will appear a dark red to the human eye (if intense enough to trigger the eye's L cones). Our eye isn't very sensitive to it but we can see it. It's frequency is near the peak transmission of most red filters so it's typically combined with the red channel. Dark red doesn't really display well on monitors either so you can lose the contrast inherent in Ha signal if you don't render it with a bit brighter red tone. Personal taste creeps in here of course.

Thanks - I'm learning all the time.

[midnight (Darrin)]

Enjoyable image Marcus. The contrast and expanse of the little side "treasures" away from the centre make this a treat - esp at 100% view.

I found myself drawn more to the contrasting areas of dark "cloud" as the subject is a well known one. So congratulations for making this a lovelly image of a well known southern object.

Darrin...

[astronobob (Bob)]

That is fantasic Marcus , it is now in my best of the best astro images folder Hope you dont mind, all your credit of coarse : )

[David Fitz-Henr]

Excellent image as usual Marcus! A good FOV too showing most of the nebula at maximum detail - well done!

[marc4darkskies (Marcus)]

Originally Posted by midnight

Enjoyable image Marcus. The contrast and expanse of the little side "treasures" away from the centre make this a treat - esp at 100% view.

I found myself drawn more to the contrasting areas of dark "cloud" as the subject is a well known one. So congratulations for making this a lovelly image of a well known southern object.

Darrin...

Many thanks Darrin! Yes, the outer areas of neb have some interesting features that I was drawn to as well that aren't seen & appreciated very often!

Originally Posted by astronobob

That is fantasic Marcus , it is now in my best of the best astro images folder Hope you dont mind, all your credit of coarse : )

Cheers Bob, that's very flattering! I'm glad you think it's worthy!

Originally Posted by David Fitz-Henr

Excellent image as usual Marcus! A good FOV too showing most of the nebula at maximum detail - well done!

Thanks David! I'm pretty happy with the resolution I achieved at F5.5 (2.1 arcsec/pixel). Thankyou Mr Takahashi!