APOD: Alnitak, Alnilam, Mintaka (2013 Dec 12)

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Expand view Topic review: APOD: Alnitak, Alnilam, Mintaka (2013 Dec 12)

Re: APOD: Alnitak, Alnilam, Mintaka (2013 Dec 12)

by Ann » Wed Dec 18, 2013 12:51 am

Galaxian, I think everybody gets what you mean by now, and no one should be offended.

Personally, I am always very grateful when an astrophotographer signs his (or her) work. I like to search for pictures to post here, and sometimes it is extremely hard or impossible to find out who is the author of a great picture. Occasionally I spend quite some time trying to find the name of the rightful owner. But if the name is there on the picture itself, then I don't have to bother! :D

Ann

Re: APOD: Alnitak, Alnilam, Mintaka (2013 Dec 12)

by geckzilla » Wed Dec 18, 2013 12:30 am

No worries, I get what you mean. Some watermarks can be pretty obtrusive. The only way to delete your account is to have an admin do that and no one has convinced one of those lazy bums to do anything since the board was created.

Re: APOD: Alnitak, Alnilam, Mintaka (2013 Dec 12)

by Galaxian » Tue Dec 17, 2013 10:31 pm

owlice wrote:Galaxian,

It is extremely easy to see that APOD images are widely shared and often, used illegally. I have a Facebook friend who reposts images that market Greece as a travel destination; because I'm familiar with APOD, I have recognized some of the images as the work of certain photographers. I alert them to the use of their images when I see them, because these images are not 1.) identified as copyrighted images; 2.) credited to the copyright holders. Some think they can grab whatever appears anywhere and use it for whatever purpose they want without attributing anything to anyone and without paying for the use. This is wrong.
I agree. Totally. I create. I like getting paid for it. I would never use your work as my own.
owlice wrote:As pointed out, APOD suggests imagers sign their work: "We do recommend that you include a small copyright notice in a corner of your submitted images." This is to protect the photographers' interests. Rather than be bothered by the desire of a photographer to protect his work, I suggest you direct your annoyance where it belongs: to those who abuse the rights of others.
Last comment, I wasn't bothered by the photographer's desire to protect his work. I *encouraged* that. I was bothered by what I saw as a coffee-cup ring on the image. Had I the tools and skill to produce an image like that I would never have ...
Ah, I'm sorry I started this.
I'm sorry I started anything.
Anyone know how to delete an Asterisk profile?

Re: APOD: Alnitak, Alnilam, Mintaka (2013 Dec 12)

by Nitpicker » Sun Dec 15, 2013 11:14 am

geckzilla wrote:I don't necessarily think a "hack" is a bad thing. They certainly make my life easier. :D
Sometimes I also find it better to "hack" at my work -- normally for commercial reasons. But "hack" is certainly a loaded word.

Re: APOD: Alnitak, Alnilam, Mintaka (2013 Dec 12)

by geckzilla » Sat Dec 14, 2013 11:02 pm

I don't necessarily think a "hack" is a bad thing. They certainly make my life easier. :D

Re: APOD: Alnitak, Alnilam, Mintaka (2013 Dec 12)

by Nitpicker » Sat Dec 14, 2013 10:44 pm

Galaxian wrote:
Nitpicker wrote:
Galaxian wrote:Don't people know they can watermark images invisibly?
I didn't, or at least I don't think I use software which can and I might not know how to find it if it was there. Regardless, owners may do as they please, for whatever reasons. The fact that this APOD was selected might indicate that it is not a big issue to the APOD judges.
I thought most image manipulation software allowed one to add comments in the metadata, the file descriptor region? The simple, cheap ones I use do.
Ah, I didn't think you were talking about the metadata or Exif format embedded in the image file (which even Windows Explorer can view or delete). I thought you were talking about a trick [or hack if you are being impolite, like I was before] with the image pixels. Besides, I'm sure my image editing software is simpler and cheaper than yours. :ssmile:

Edit reason: incorrect quote tags

Re: APOD: Alnitak, Alnilam, Mintaka (2013 Dec 12)

by owlice » Sat Dec 14, 2013 9:12 pm

Galaxian,

It is extremely easy to see that APOD images are widely shared and often, used illegally. I have a Facebook friend who reposts images that market Greece as a travel destination; because I'm familiar with APOD, I have recognized some of the images as the work of certain photographers. I alert them to the use of their images when I see them, because these images are not 1.) identified as copyrighted images; 2.) credited to the copyright holders. Some think they can grab whatever appears anywhere and use it for whatever purpose they want without attributing anything to anyone and without paying for the use. This is wrong.

As pointed out, APOD suggests imagers sign their work: "We do recommend that you include a small copyright notice in a corner of your submitted images." This is to protect the photographers' interests. Rather than be bothered by the desire of a photographer to protect his work, I suggest you direct your annoyance where it belongs: to those who abuse the rights of others.

Re: APOD: Alnitak, Alnilam, Mintaka (2013 Dec 12)

by Galaxian » Sat Dec 14, 2013 8:33 pm

RBAndreo wrote:
Galaxian wrote:It would have been a beautiful image had not the creator decided to mar it with his ownership details. True, cutting off a chunk isn't too onerous but that rather spoils the owners original work and I'm not sure that's strictly legal. Don't people know they can watermark images invisibly?
Watermarks are used to avoid copyright infringements. In this case, the author simply wants to "sign" the image - which is what you don't like - and he chose one of the areas where it could less interfere with the view of the photograph as a whole (usually that's one of the lower corners). I know because I'm the author :ssmile: No need to start a debate, we all have our preferences.
Thank you for explaining and thank you for sharing.
It is a gorgeous image of a lovely part of our Galaxy but you are right, I'm petty and pouty and I want all my freebies to be perfect and I don't like signatures on images, or paintings. It's like the DOGs, digital online graphics, TV companies use as IDents and teasers. Five thousand SFX guys spend ten years getting something just right, two actors work their butts off to portray deep emotion in a blank room in front of a green screen and the dumb TV guys cut their heads off, run a crawler over the effects and generally ruin it. A small signature isn't in that class but it's still obtrusive to nitpickerry perfectionists.
Like me.
I don't feel right cutting off a signature, that feels vaguely like vandalism of a mild sort but if I could magically extinguish the TV DOGs I would.
And you're right, I shouldn't have mentioned it.
Bye.

Re: APOD: Alnitak, Alnilam, Mintaka (2013 Dec 12)

by Galaxian » Sat Dec 14, 2013 8:21 pm

Anthony Barreiro wrote:What a gloriously beautiful image. If I had created something like this, I would certainly sign my name to it. By the way, who does that Van Gogh guy think he is, scrawling his name on an otherwise perfectly beautiful picture of daisies? :lol2:
Okay. Point taken. I won't do it again. However, to be fair to modern creators, van Gogh didn't have electronic means of hiding copyright notices in his paintings. He could have used lemon juice or something equally invisible but those decay and become coloured. Anyway, van Gogh wasn't expecting us to have his paintings on our monitors, and he was hoping to get paid for every copy used. It is our very good fortune that APoD and the creators who so generously share their work are kinder to us.

Re: APOD: Alnitak, Alnilam, Mintaka (2013 Dec 12)

by Galaxian » Sat Dec 14, 2013 8:14 pm

geckzilla wrote:Also, silly graphics tricks. Not an "invisible" watermark but a very sneaky one just for fun. See if you can find it. Note: It might be completely obvious if you are red-green colorblind but I'm not sure about that.
Thanks for the hint. I was looking for something tiny and obscure. Your watermark is hardly either of those. It's cute, though.
http://en.wikipedia.org/wiki/Steganography and https://www.google.co.uk/search?q=watermark+images might be useful.

Re: APOD: Alnitak, Alnilam, Mintaka (2013 Dec 12)

by Galaxian » Sat Dec 14, 2013 8:06 pm

Nitpicker wrote:
Galaxian wrote:Don't people know they can watermark images invisibly?
I didn't, or at least I don't think I use software which can and I might not know how to find it if it was there. Regardless, owners may do as they please, for whatever reasons. The fact that this APOD was selected might indicate that it is not a big issue to the APOD judges.
I thought most image manipulation software allowed one to add comments in the metadata, the file descriptor region? The simple, cheap ones I use do.
Nitpicker wrote:Perhaps you would like to propose the details of a standard method for owners to assert their moral rights? Personally, the variation doesn't bother me at all.
I'm not entirely comfortable with that. I don't know what software real professionals use so I don't know how it works and what it can't do. In addition to which, unless its something I've been using for years the other guys will know more about their software than I will. Even if it is something I've used for years they probably use it more.

Re: APOD: Alnitak, Alnilam, Mintaka (2013 Dec 12)

by Galaxian » Sat Dec 14, 2013 7:58 pm

geckzilla wrote:Actually, people who submit images to APOD are encouraged to leave a small note in the corner like that.
Oh. Didn't know that. Sorry.
Why?

Re: APOD: Alnitak, Alnilam, Mintaka (2013 Dec 12)

by Nitpicker » Fri Dec 13, 2013 9:18 am

geckzilla wrote:
Nitpicker wrote:I'm not colourblind at all AFAIK, but my mind doesn't respond strongly to colour, either. I can make out a yellowish "Nitpicker!" in your original straya image. In my line of work, that would be called a hack and would be frowned upon. :ssmile:
Well, it's impossible for me to say without going to your house and looking at your screen to see if it's your monitor displaying it better for you or if you are more sensitive to blue than I am. I can see some slight yellowing but only because I put it there. I can't read it unless I look at the blue channel.]
I wouldn't say it jumped out at me. I had to zoom in before I could see it well enough, and it was still very low contrast. Interesting nonetheless, thanks geckzilla.

And thanks for the lovely picture, too, Mr Andreo.

Re: APOD: Alnitak, Alnilam, Mintaka (2013 Dec 12)

by Anthony Barreiro » Fri Dec 13, 2013 5:12 am

Ann, thank you for the lesson about stellar evolution. I really appreciate it. My initial love for Sigma Orionis grows from how interesting it looks through a little telescope, so it's great to learn more about it. I knew that A and B are young main sequence O stars, but I didn't know that they're less bright than they will be after they evolve off the main sequence. Of course it makes sense as you explain it. The fact that Sigma Ori might backlight the Horsehead nebula would be more personally exciting to somebody with a bigger telescope and a camera. :ssmile:

Re: APOD: Alnitak, Alnilam, Mintaka (2013 Dec 12)

by geckzilla » Fri Dec 13, 2013 2:46 am

Nitpicker wrote:I'm not colourblind at all AFAIK, but my mind doesn't respond strongly to colour, either. I can make out a yellowish "Nitpicker!" in your original straya image. In my line of work, that would be called a hack and would be frowned upon. :ssmile:
Well, it's impossible for me to say without going to your house and looking at your screen to see if it's your monitor displaying it better for you or if you are more sensitive to blue than I am. I can see some slight yellowing but only because I put it there. I can't read it unless I look at the blue channel.
RBAndreo wrote:Watermarks are used to avoid copyright infringements. In this case, the author simply wants to "sign" the image - which is what you don't like - and he chose one of the areas where it could less interfere with the view of the photograph as a whole (usually that's one of the lower corners). I know because I'm the author :ssmile: No need to start a debate, we all have our preferences.
Hello, Mr. Andreo. :)

Re: APOD: Alnitak, Alnilam, Mintaka (2013 Dec 12)

by Nitpicker » Fri Dec 13, 2013 2:42 am

geckzilla wrote:Also, silly graphics tricks. Not an "invisible" watermark but a very sneaky one just for fun. See if you can find it. Note: It might be completely obvious if you are red-green colorblind but I'm not sure about that.
straya.jpg
I'm not colourblind at all AFAIK, but my mind doesn't respond strongly to colour, either. I can make out a yellowish "Nitpicker!" in your original straya image. In my line of work, that would be called a hack and would be frowned upon. :ssmile:

Re: APOD: Alnitak, Alnilam, Mintaka (2013 Dec 12)

by RBAndreo » Fri Dec 13, 2013 2:32 am

Galaxian wrote:It would have been a beautiful image had not the creator decided to mar it with his ownership details. True, cutting off a chunk isn't too onerous but that rather spoils the owners original work and I'm not sure that's strictly legal. Don't people know they can watermark images invisibly?
Watermarks are used to avoid copyright infringements. In this case, the author simply wants to "sign" the image - which is what you don't like - and he chose one of the areas where it could less interfere with the view of the photograph as a whole (usually that's one of the lower corners). I know because I'm the author :ssmile: No need to start a debate, we all have our preferences.

Re: APOD: Alnitak, Alnilam, Mintaka (2013 Dec 12)

by Beyond » Fri Dec 13, 2013 1:59 am

Ha-ha, wadda watermark.

Re: APOD: Alnitak, Alnilam, Mintaka (2013 Dec 12)

by geckzilla » Fri Dec 13, 2013 1:35 am

rstevenson wrote: I had to do a little image manipulation, but I think I got it. :mrgreen:
Rob

Yup!
Alternatively, you don't have to do any color manipulation. You can simply view the blue channel for the image and it becomes clear as day.
I also studied red-green color blindness a little and came to the realization it works fine if you have that too. Now I think I can simulate what any red-green color blind person sees with the Photoshop channel mixer.

Re: APOD: Alnitak, Alnilam, Mintaka (2013 Dec 12)

by rstevenson » Fri Dec 13, 2013 1:22 am

geckzilla wrote:Also, silly graphics tricks. Not an "invisible" watermark but a very sneaky one just for fun. See if you can find it. Note: It might be completely obvious if you are red-green colorblind but I'm not sure about that.
I had to do a little image manipulation, but I think I got it. :mrgreen:
file.jpg
Rob

Re: APOD: Alnitak, Alnilam, Mintaka (2013 Dec 12)

by Ann » Fri Dec 13, 2013 1:17 am

Anthony Barreiro wrote:
Sigma Ori appears less bright that the three brightest stars of Orion's belt simply because it is further away. In reality it's hella bright and going to give future astronomers a very interesting supernova to observe.
I only partly agree. Yes, the brightest components of Sigma Orionis are very bright, and they will almost certianly produce a supernova in the future - or two!! But I don't agree that Sigma Orionis looks fainter than the Belt stars simply because it is farther away than Alnitak, Alnilam and Mintaka. In particular, I am not at all sure that it is necessarily farther away than Alnilam.

Stars grow brighter as they age, and that is true even for hot stars, before they turn into swollen giants or supergiants. Sigma Orionis is - as you pointed out - a young cluster, indeed so young that even its most massive member, Sigma Orionis A, is unevolved. It is still on the main sequence, fusing hydrogen in its core. And while it is an O-type star, it is about as cool as an O-type star can be, with a spectral classification of O9.5.

I have taken an intense interest in the properties of blue stars, and one thing that I think I have learnt is that you just can't guess the brightness of hot star from its spectral classification or B-V index. The best way to find out about its brightness is indeed to measure the exact distance to it. The distance to Sigma Orionis has not been well measured at all, for two reasons: The small cluster is far away, and the two brightest components are sufficiently well separated to be clearly resolved, and sufficiently close to one another to play hell with one another's parallaxes.

So we don't really know how far away Sigma Orionis is, although it is probably farther away than Alnitak and Mintaka. But in my opinion, Sigma Orionis is certainly fainter (and possibly no farther away) than Alnilam, at least. Alnilam appears to be an absolutely hugely bright and massive star. Unlike main sequence stars Sigma Orionis, Alnilam is evolved and classified as a supergiant of spectral class B0Ia. According to its (uncertain) Hipparcos parallax, Alnilam might be as bright as 64,000 times the Sun in visual light. That is an enormous brightness for a star as hot as spectral class B0, since it will radiate most of its energy as ultraviolet light. It must be admitted that Alnilam is not as hot as Sigma Orionis A. Jim Kaler estimates the temperature of Alnilam at 25,000 K, while Sigma Orionis A has a likely temperature of 32,000 K. However, Alnilam is certainly a much bigger star than Sigma Orionis A.

And we may compare Alnilam with Rigel. We are often taught that Rigel is a fantastically bright and massive blue supergiant. Yes, Rigel is impressive, but it pales when compared with Alnilam. The V magnitude of Rigel (11,500 K) may be some 49,000 times that of the Sun, compared with perhaps 64,000 times that of the Sun for Alnilam. But because Alnilam is more than twice as hot as Rigel, it emits many times more ultraviolet light than Rigel.

Alnilam, as far as I can understand, is one of the truly, truly bright hot stars that are moderately close to the Earth. Not many other nearby very hot stars stand out because of their high output of V light on top of their fantastic production of ultraviolet light. As for Sigma Orionis, it may well be quite bright (even in V light) for its spectral class, but I don't think that it will ever turn into an "Alnilam".

A final note on Sigma Orionis. David Malin claimed that it is Sigma Orionis that ionizes the red "curtain" of luminosity that provides a backdrop to the Horsehead Nebula. That's as good a claim to fame as anything - for Sigma Orionis, that is - if you ask me! :D

Ann

Re: APOD: Alnitak, Alnilam, Mintaka (2013 Dec 12)

by Anthony Barreiro » Fri Dec 13, 2013 12:28 am

What a gloriously beautiful image. If I had created something like this, I would certainly sign my name to it. By the way, who does that Van Gogh guy think he is, scrawling his name on an otherwise perfectly beautiful picture of daisies? :lol2:

On a more serious note, I want to shout out to one of my favorite multiple star systems, Sigma Orionis, the relatively bright star that's directly above the Horse's head in this image, forming a nearly equilateral triangle with the Horsehead and Alnitak. Sigma Ori is actually five incredibly big, hot, bright young stars all gravitationally bound to one another. Rogelio's picture shows the big hot binary AB pair as a single star, the C component of the system to the lower right, and the resolved DE pair to the upper right, and this is how it looks through a small telescope under decent observing conditions. Sigma Ori appears less bright that the three brightest stars of Orion's belt simply because it is further away. In reality it's hella bright and going to give future astronomers a very interesting supernova to observe.

Re: APOD: Alnitak, Alnilam, Mintaka (2013 Dec 12)

by geckzilla » Fri Dec 13, 2013 12:23 am

Also, silly graphics tricks. Not an "invisible" watermark but a very sneaky one just for fun. See if you can find it. Note: It might be completely obvious if you are red-green colorblind but I'm not sure about that.
straya.jpg

Re: APOD: Alnitak, Alnilam, Mintaka (2013 Dec 12)

by geckzilla » Thu Dec 12, 2013 10:32 pm

You can put copyright information in the EXIF headers but not everyone knows how to look at those. Leaving a name and website URL in one of the corners is the best way to ensure that anyone viewing the image out of its intended context will be able to easily determine the origin as long as it doesn't get cropped off. EXIF headers could serve as a backup in that case but sometimes image editing programs strip them too.

Re: APOD: Alnitak, Alnilam, Mintaka (2013 Dec 12)

by Nitpicker » Thu Dec 12, 2013 10:26 pm

Galaxian wrote:Don't people know they can watermark images invisibly?
I didn't, or at least I don't think I use software which can and I might not know how to find it if it was there. Regardless, owners may do as they please, for whatever reasons. The fact that this APOD was selected might indicate that it is not a big issue to the APOD judges.

Perhaps you would like to propose the details of a standard method for owners to assert their moral rights? Personally, the variation doesn't bother me at all.

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