Editing Astronomy Images

[Celestron]

Everyone please keep in mind that Astronomy images are not like other images of other catagories . Astronomy helps everyone to learn about Deep Space Objects which include Galaxies , Nebulaes , Star Clusters ( Open & Globular) , Dark Matter , Dark Nebulaes , Planets in our Solar System , Man-Made Objects that orbit within our Solar System , Our Sun , Effects of the Sun which cause Auroras , and etc., etc....... .

The best way to demostrate this is to image space objects and share with people interested in space and Astronomy for Man-Kind . This is the whole purpose of the Astronomy section being added as a catagory of it's own here on P.O.T.N. that are imaged with a Canon product preferably with a Canon camera since this forum does belong to CANON .

Seems over this past year the most popular Space Object has been Earths very own Moon . However PLEASE when you take a picture of anything that has to do with space PLEASE keep your image as original as possible . Slight editing as needed to ehance an image and not over exaggerating an image is permissable which also includes sharpening as needed , saturation as needed ( but not over saturation ) , stacking composite images to add data and signal . Changing colors of an object should not be permissable , such as coloring the Moon for example to solid blue or red or green . I think you understand what is being mentioned .

If we produce images any other way they are no longer considered original astronomy images which changes their classification to Art and should be placed in the Art catagory instead of the Astronomy catagory . Please help all of us interested in Astronomy imaging to keep your images original for this Astronomy section .

Just because you can use the Hue/Saturation tool in PhotoShop to make the moon look like it has three different colors does not mean the Moon is actually three different colors cause it isn't !! If you are not color blind you can look up at the moon any given night of the year and see it's bright and projected in a grayscale color and every time you take a picture of the moon if your camera isn't broken it will produce a grayscale colored moon image . If your camera produces a Purple Moon then you better send it in to Canon for repairs .

It's been argued over and over but color enhancement is caused when you edit an image and change the colors yourself . If an object in space is of different colors such as Galaxies , Nebulaes and Star Clusters and Single Stars they will show up in your image colored depending how much signal and data you have collected .

If you have problems determining colors of an object then look that object up in other Astronomy Websites posted by Amateur Astronomers or Astronomy websites throughout the web .

And last but least PLEASE POST YOUR IMAGE IN THE RIGHT CATAGORY whether it's Astronomy , Landscape , WildLife , or Art , etc...... . If you do this then the MODERATORS will not have to move your topic accordingly to the right section . This topic is not to upset members , it's a reminder what the Canon Forum is all about !! If it didn't matter then there would only be one catagory .... "Pictures from Canon Cameras" !

Thank you for abiding by the rules and enjoy the forum !! Hopefully the MODERATORS will make this a "STICKY" PLEASE .

[aVisage]

Maybe change the topic of your thread to be representitive of it's contents. I was expecting to find an interesting resource or some questions that might answer something similar i was pondering.

'Why you should resist over-editing astronomy pics' or something. Otherwise I had no idea what you were on about till the 3rd paragraph.

[chris.bailey]

Ron

I understand the sentiment of your post but I am not sure I wholly concur. Many of our beloved space onjects have emissions that our outside of the visible colour spectrum. We tend to represent these by 'shifting' them into the visible range. This, to a degree, is false colouring. There are some fantastic Hubble Pallette images around whch bare little resemblance to reality in the usual sense of the word.

Multi Colour Moons are, I agree, stretching things a little, but in Astro Photography a degree of latitude is needed.

[DonR]

Hi Ron,

Deep sky photos would be drab indeed if they were shown as the eye sees them. Even the great Orion Nebula appears mostly gray through the largest telescopes, with at the most a slight green cast - and that's not because the red color seen in photos is entirely outside of the visible spectrum, it's because the human eye isn't sensitive to low levels of color. Even if an astronaut were close to the great nebula it would appear gray and faint to the eye, and the closer the astronaut approached the fainter it would appear. Astrophotography is all about displaying celestial objects in ways that the eye can't see.

Removing the IR blocking filter from a DSLR and using narrow-band filters result in changing the "natural" color balance of deep space objects, but even photographing them with an unmodified color camera, digital or film, results in images that are more colorful than the eye can see with or without a telescope.

The moon, which is a favorite subject for this forum, isn't gray at all. If you increase the saturation of a photograph of a gray object, the result is a gray object. The Milky Way too is multi-colored, containing virtually every color in the spectrum, but your unaided eye can't see those colors even from the darkest places on earth or from space beyond the earth's atmosphere. Displaying the colors of the universe beyond earth are the province of photography because the human eye alone isn't capable of it.

If another photographer's representation of a subject doesn't please you, you are free to say so or to silently disapprove, but I respectfully suggest that you should not try to force your notions of correctness on other photographers.

Don

[Celestron]

Chris - Don , i think you totally missed my point of this topic . I don't know your astronomy experience and how long you have been doing this hobby and i don't claim to be an expert in the field but i have been in it for 10+ years and around the block for quite some time . I don't take perfect images and i don't post like the pros that have pro equip. I'm not the smartest but i'm not a beginner so over the years i have looked and seen thousands of images , read hundreds of editing techniques , been in plenty of discussions about what is true colors , and been members of several astronomy forums , have had several images web published and one in Sky&Telescope magazine published . So i do know a little what an image is or should look like .

I can tell alot of times what quality of a scope an image has been taking with by seeing the quality of the image produced because there is alot of expert editers out there . So i know when an image has been over done or color changed that doesn't seem right . I also know that special editing is needed to bring out special spectrum colors of certain images but when that is done the imager of such images usually states the reason and explains his technique to a certain degree of understanding . I've looked at the Orion nebulae a thousand times and i know it is grayscale to most eyes through a telescope but even myself have detected a slight green tint from M42 and to me it's one of the most gorgeous nebulaes in our sky trhrought a telescope .

But i have also imaged it several times and from a camera color will be produced in some way or other . I've imaged M31 several times and stacking alot of images bring out some color but i find it hard for me to bring out the nice colors properly because of my editing technique and software i use (mainly PS7) and i'm no expert but i do know that M42 has a standard and most accepted color of a red shade with a lighter chest area and if i see M42 that is yellow with a green chest then you know as well thats not what it should look like . M45s' most accepted color is a shade of blue as we all know but if someone post it as a purple color we also know this isn't right .

Now if someone did a spectrum image of either one and it shows other colors and it is stated the reason then that is acceptable for the reason . And last but least as far as the colors of the moon , comon' guys ..... , you know when you look at the moon with the naked eye you don't see brown , or red , or purple....(lol) . You see it in grayscale color cause no human can see color beyond a few miles into space unless it's an airplane flying overhead and you see the bright color blinking lights . And when you take a picture of the moon then why doesn't brown , red , green or purple colors show in your un-edited image ?? Dark or bright the moon always comes out a grayscale color unless you have some type distortion in the sky like fog , smoke , or low horizon shots where your not seeing the moon clearly . I;ve taken moon shots with film where the moon was in clouds passing and the clouds came out orangish color with blue but the moon was still grayscale color . I think by now you get my point of my original post i hope .

The whole point is i'm asking that imagers please post images close as possible to original as you can . Don't post a picture of a over-saturated Blue Moon just because your trying to be funny ! It's called a Blue Moon for the astronomy reason of it being the Second Full Moon of a given month and i'm using this as an example . How is members here going to learn what astronomy imaging is all about if everything is accepted no matter what it looks like ?? If you wish to do so then just post your images in the Art Gallery section or whatever other section it may go with . But PLEASE !! Lets' keep this astronomy section clean and proper and HONEST .

[Celestron]

Maybe change the topic of your thread to be representitive of it's contents. I was expecting to find an interesting resource or some questions that might answer something similar i was pondering.

'Why you should resist over-editing astronomy pics' or something. Otherwise I had no idea what you were on about till the 3rd paragraph.

Sorry you did not find what you were expecting , my apologies . But the title is fitting for the reason of this topic . Not to teach you how edit your images , it's to help you understand to not over do something that is not there . If you did a landscape image you should not oversaturate the whole image in one color just cause it looks neat to you then post it in the Landscape Section and hope to get good comments would you ? You would want that image to be as best looking of that landscape as you saw it with your naked eyes . If you took a picture of a big grizzly at YellowStone NP you wouldn't change the color to purple and post it in the WildLife section would you ?? Not unless you wanted to get bad comments . Why take a good image of anything and change the way it looks by over editing or over-saturated ?? Do i make things more understandable now ?? Thanks for reading and post some good images and have fun !

[DonR]

Well said, Ron, but the fact is that nearly all astrophotography represents the photographer's interpretation of the subject. Your experience includes some deep sky imaging, as I see from your home page, so no doubt you understand that unprocessed long exposures of the night sky taken from most locations on earth do not have a natural or pleasing color balance. It is the photographer's job to balance the colors, and the task is complicated by many variables, incuding the degree of light pollution, the spectral response of the film or digital sensor, type of filter used if any, and the color response of the digital photographer's monitor and graphics card. If the photographer's goal is to present an image that matches the colors seen in most other photographers' images of the same subject, that's fine, and most astronomy image processing software can do that pretty much automatically. If the photographer's goal is to enhance the colors of a subject that has low saturation, or even to present false colors, I don't see anything wrong with that.

Many images of the moon display distinct, evenly distributed yellow to orange casts, and even if these were the colors recorded by the camera due to atmospheric refraction, they are not the true colors of the moon. Recently many photographers, including I, have followed a procedure published in Sky and Telescope magazine to increase the saturation of lunar images without changing the color balance. The results look nothing at all like the moon we see with our unaided eyes or even through a telescope, but nevertheless they represent, if done carefully, the true colors of the moon's surface. In much the same way, the red color seen in most images of M42 and other emission nebulae represent the true colors of these objects, even though nobody will ever see those colors with their unaided eyes or through any telescope. As long as the photographer is not misrepresenting the subject or making false claims about the image, this is perfectly acceptable IMHO in any forum dealing with astrophotography imaging.

[Bernoulli]

I'd like to see more folks (even me) post their unedited moon pictures along with whatever processed version they've made. I know that means another upload, but it would serve to show what you can get straight out of the camera and would help distinguish between what's real and what's invented in PP.

Also, I agree with Ron's particular peeve about Canon cameras only. There are plenty of astronomy forums for showing off your webcam pictures so let's stick to Canon for this site. And always tell us what equipment you used and how you used it.

[Sorarse]

I understand what Celestron is saying, but this is principally a photography forum that just happens to have an astronomy sub-forum.

I am not an astronomer, and I haven't spent years studying images that true astronomers have produced, so if I happened to produce an image after a few hours of gathering data from one of the lesser Messier objects, I wouldn't have a clue if my rendition of that object was true to life or not. What is important to me is whether I am happy with the end result. If others happen to like it, then that's a bonus. But is it right that I shouldn't post it here if it doesn't meet with someone else's interpretation of what it should look like?

[Celestron]

Well said, Ron, but the fact is that nearly all astrophotography represents the photographer's interpretation of the subject. Your experience includes some deep sky imaging, as I see from your home page, so no doubt you understand that unprocessed long exposures of the night sky taken from most locations on earth do not have a natural or pleasing color balance. It is the photographer's job to balance the colors, and the task is complicated by many variables, incuding the degree of light pollution, the spectral response of the film or digital sensor, type of filter used if any, and the color response of the digital photographer's monitor and graphics card. If the photographer's goal is to present an image that matches the colors seen in most other photographers' images of the same subject, that's fine, and most astronomy image processing software can do that pretty much automatically. If the photographer's goal is to enhance the colors of a subject that has low saturation, or even to present false colors, I don't see anything wrong with that.

Many images of the moon display distinct, evenly distributed yellow to orange casts, and even if these were the colors recorded by the camera due to atmospheric refraction, they are not the true colors of the moon. Recently many photographers, including I, have followed a procedure published in Sky and Telescope magazine to increase the saturation of lunar images without changing the color balance. The results look nothing at all like the moon we see with our unaided eyes or even through a telescope, but nevertheless they represent, if done carefully, the true colors of the moon's surface. In much the same way, the red color seen in most images of M42 and other emission nebulae represent the true colors of these objects, even though nobody will ever see those colors with their unaided eyes or through any telescope. As long as the photographer is not misrepresenting the subject or making false claims about the image, this is perfectly acceptable IMHO in any forum dealing with astrophotography imaging.


I understand what your saying Don but what i don't understand is why change an image to something not really acceptable that new members don't know is not true ? I know there is techniques and ways to bring out different colors o the moon but solid blue (for example) ?? Comon' , get real ! Ive seen the moon images that Rick has produced but they have become acceptable throughtout the astronomy hobby and he happens to be very good at it because it doesn't make it look like art .

[Celestron]

I understand what Celestron is saying, but this is principally a photography forum that just happens to have an astronomy sub-forum.

I am not an astronomer, and I haven't spent years studying images that true astronomers have produced, so if I happened to produce an image after a few hours of gathering data from one of the lesser Messier objects, I wouldn't have a clue if my rendition of that object was true to life or not. What is important to me is whether I am happy with the end result. If others happen to like it, then that's a bonus. But is it right that I shouldn't post it here if it doesn't meet with someone else's interpretation of what it should look like?


When you take alot of images and stack them the color you see from stacking is primarily already close to it's true color . Slight enhancement to better the image is acceptable to make it pleasing to you and to the posting for others to enjoy . If you take a picture of M42 and stack it and it comes out red , you wouldn't use the HUE/Saturation tool in PS to change it to green would you ?? Thats a point i'm making . Your also right that this is a sub-forum of a Principle Photograhy Forum and now that i think about it it seems a few of us amateur astronomers perhaps made a mistake to get this Astronomy Section started . Perhaps i'm posting in the wrong section as is . Have fun Sorarse and everyone else .

[Bernoulli]

I'm not sure I'm being praised or blamed here so let me respond either way.

I'm probably the most single-minded post-processor in this sub-forum; I process Moon pictures to maximize information in the image. That's because I do so much of that at work but with another moon - Iapetus. One of my grad students, along with some folks at JPL, are taking all the images of Iapetus we can find (from Voyager and Cassini) and are stitching them together to form the best map of the moon we can get. I guess the workflow habits follow me home, but that's what I'm after in PP.

I'm in broad agreement with Ron on this issue, but I look at as the difference between photography and art. This is a photography forum and any processing that inserts color or features that aren't there has no place in this forum, IMHO.

[Celestron]

I'm not sure I'm being praised or blamed here so let me respond either way.

I'm probably the most single-minded post-processor in this sub-forum; I process Moon pictures to maximize information in the image. That's because I do so much of that at work but with another moon - Iapetus. One of my grad students, along with some folks at JPL, are taking all the images of Iapetus we can find (from Voyager and Cassini) and are stitching them together to form the best map of the moon we can get. I guess the workflow habits follow me home, but that's what I'm after in PP.

I'm in broad agreement with Ron on this issue, but I look at as the difference between photography and art. This is a photography forum and any processing that inserts color or features that aren't there has no place in this forum, IMHO.


Thanks Rick , you get Praised ! You do understand what i'm trying to get across and everyone has their right to their own opinion and and interpretation . I was using you for an example of PP of the moon . You do a great job PP and i really like your work and i also like the fact that when you started doing this you explained what and why you were doing it and took it seriously in your work and i commend you for that along with your school work ! I also know that others do understand what i'm talking about but seem to not want to agree and they have their right so i'm going to just leave it alone for now and let everyone enjoy whatever they post in the astronomy section as they see fit . There is a UK Imaging forum (http://ukastroimaging.co.uk/forums/index.php) i've been a member of for years and these guys take everything serious and produce so many images of all DSOs' including planets that i can't even keep up with them in commenting their image but at least they try sincerely to produce the best image they can and they don't over do it . Check it out sometime when you get a chance ! Keep up the good work Rick !

[aVisage]

When you take alot of images and stack them the color you see from stacking is primarily already close to it's true color . Slight enhancement to better the image is acceptable to make it pleasing to you and to the posting for others to enjoy . If you take a picture of M42 and stack it and it comes out red , you wouldn't use the HUE/Saturation tool in PS to change it to green would you ?? Thats a point i'm making .

So the picture of the moon I posted in the other thread, which came out of the camera with a significant red cast to it, i shouldn't have adjusted the white balance in post using hue/sat as that's made it art and not astro photography? Where do you draw the line, who decides what "slight enhancement" is?

You should probably get emailing NASA and tell them to knock it off if this sort of thing upsets you.
http://apod.nasa.gov/apod/ap060907.html
http://apod.nasa.gov/apod/ap060216.html
http://apod.nasa.gov/apod/ap020316.html
If anything increasing the saturation of the colours of the moon seems demonstrative of a scientific technique for showing the elemental makeup of the moons landscape. Surely that would make it relevant to this forum, even if you personally find the pictures aesthetically displeasing.

[Celestron]

So the picture of the moon I posted in the other thread, which came out of the camera with a significant red cast to it, i shouldn't have adjusted the white balance in post using hue/sat as that's made it art and not astro photography? Where do you draw the line, who decides what "slight enhancement" is?

You should probably get emailing NASA and tell them to knock it off if this sort of thing upsets you.
http://apod.nasa.gov/apod/ap060907.html
http://apod.nasa.gov/apod/ap060216.html
http://apod.nasa.gov/apod/ap020316.html
If anything increasing the saturation of the colours of the moon seems demonstrative of a scientific technique for showing the elemental makeup of the moons landscape. Surely that would make it relevant to this forum, even if you personally find the pictures aesthetically displeasing.


Yes i'm aware of these images . I also know Noel Carboni (http://ncarboni.home.att.net/) and about this image . He's works for NASA editing images taken from the Hubble Space Telescope and he is partners with another Pro Amateur Astronomer , Greg Parker (http://www.newforestobservatory.com/) and edits more than 90% of his images for him . In one of your links is Noels' image of the moon with stars behind it and NO bright moon but a false color moon . If you read the discription below each of your links you will find the moon was either false color or colors greatly exaggerated . Re-read the other postings i made and try to understand my point . Have a great day !

[SteveInNZ]

I understand what you're saying Ron, but on the whole I have to disagree. I find images like Rick's oversaturated moon shots particularly interesting and I would hate to discourage them. I really can't see any ethical difference between those and M42 showing the trapezium and any hint of red in the same image. It's the astro version of the HDR debate I guess.
I have no interest in artificially colored moons. To each their own. I just click the back button if it's not to my taste.

I find this forum encouraging as it is (blue moons and all) so I'd rather keep it as is. Most other astrophotgraphy forums can be rather intimidating. There's no doubt that this one is encouraging others to give it a try while at the same time keeping the more capable imagers here. That seems a pretty good overall result to me.

I tend to agree on the Canon thing.

Steve.

[Nighthound]

This is a good discussion point Ron and I think the replies thus far are in fundamental agreement. I completely agree with your basis for this post as well.

The subject only becomes muddy due to the fact that we're talking about photography which is art. As we all know art is subjective and there in lies a broad spectrum of interpretation. In astrophotography, especially deep-sky it's even more complicated since we photograph subjects that no one has actually seen with eyes built for the job.

-----------------

FROM A DEEP-SKY PERSPECTIVE:
I believe authenticity in astrophotography relies on staying true to the data collected. Understanding that the data will have flaws and correction of those flaws, i.e. color balance, which I feel is an example of "ethical" data manipulation. The color imbalance occurred in large part from light pollution, so removing it or reducing it brings the data closer to it's raw form before entering Earth's atmosphere. So in essence we are correcting the data to be more natural even though we could never actually view it that way. We add saturation to counter the low level of color due to the low levels of light which I feel is "ethical" and also plays into the art aspect of making an image more colorful and pretty to look at. I suppose NASA has equipment that can determine the accurate level of color saturation and over the years images like those from the Hubble have helped set standards for color accuracy. Over time the high-end astrophotographers that fall into the "pro" category have also fine tuned and helped to set the standards of how objects we image should look. Knowing what we know and more importantly don't know about space, there's always going to be a degree of doubt on what we perceive to be accurate. So we rely on what we know now and have for reference, striving to match that is what I do.

FROM A SOLAR SYSTEM PERSPECTIVE:
The sun-drenched Lunar surface has until recent years been depicted as an almost grayscale objects as Ron mentioned. The lack of color in this case is not due to faint light but rather the amount of pigment. In recent years the arrival of saturation-enhanced Lunar images offers a fresh look at the Moon. I find it very interesting to see the saturated renditions that reveal the various colors we cannot see regardless of the devices or filters we use. Traditional?, no but interesting and educational. Producing a Lunar image that is color enhanced to make it other than true to its content moves it from astrophotogaphy into astro illustration in my opinion. It doesn't make it any less a photograph, it's just not true to the data collected as are the traditional and saturated methods.

--------------------

As far as cameras go, from what I've been able to gather this site does not prohibit the use of non-Canon cameras. Also, POTN is not owned by Canon the corporation. This thread covers both points:
http://photography-on-the.net/forum/showthread.php?t=606953&highlight=canon+sponsor+potn

Many people using dedicated astro CCD cameras started out using DSLRs. They may not fall into the majority here but they still bring a lot of knowledge to the table. Their current work using a dedicated astro camera offers insight and inspiration for those that will follow the same path one day.

I have no objection to the use of non-Canon cameras. I'm concerned most about whether or not the image presented by a member is a means to others learning or advancing their skills. Show me a sculpture and I won't ask which brand chisel you used. I'm more concerned about how you did it, how long it took, etc., etc. I hope that we won't lose sight of the fact that we are fortunate to have a place here at POTN for sharing, learning and enjoying this hobby in a diverse forum.

I haven't noticed anyone posting web cam images but the best planetary images I've ever seen (outside NASA) were taken using web cams. I don't shoot planetary but someone starting out that does would benefit from someone's posts that elaborate on the methods used. Again . . . sharing, learning and fun.

[Celestron]

I understand what you're saying Ron, but on the whole I have to disagree. I find images like Rick's oversaturated moon shots particularly interesting and I would hate to discourage them. I really can't see any ethical difference between those and M42 showing the trapezium and any hint of red in the same image. It's the astro version of the HDR debate I guess.
I have no interest in artificially colored moons. To each their own. I just click the back button if it's not to my taste.

I find this forum encouraging as it is (blue moons and all) so I'd rather keep it as is. Most other astrophotgraphy forums can be rather intimidating. There's no doubt that this one is encouraging others to give it a try while at the same time keeping the more capable imagers here. That seems a pretty good overall result to me.

I tend to agree on the Canon thing.

Steve.


Sorry you disagree Steve , it's your right to . BTW did you notice how i've commented on your images you posted here ? I noticed your moon mosaics were pretty much original and i also commented there . Did i perhaps comment in the wrong way . i'm not sure ?? Perhaps if they were solid purple would i have commented differently , i'm not sure ? But the ones you did post were great including your DSO image .

[Celestron]

This is a good discussion point Ron and I think the replies thus far are in fundamental agreement. I completely agree with your basis for this post as well.

Thanks Steve


The subject only becomes muddy due to the fact that we're talking about photography which is art. As we all know art is subjective and there in lies a broad spectrum of interpretation. In astrophotography, especially deep-sky it's even more complicated since we photograph subjects that no one has actually seen with eyes built for the job.

-----------------

FROM A DEEP-SKY PERSPECTIVE:
I believe authenticity in astrophotography relies on staying true to the data collected. Understanding that the data will have flaws and correction of those flaws, i.e. color balance, which I feel is an example of "ethical" data manipulation. The color imbalance occurred in large part from light pollution, so removing it or reducing it brings the data closer to it's raw form before entering Earth's atmosphere. So in essence we are correcting the data to be more natural even though we could never actually view it that way. We add saturation to counter the low level of color due to the low levels of light which I feel is "ethical" and also plays into the art aspect of making an image more colorful and pretty to look at. I suppose NASA has equipment that can determine the accurate level of color saturation and over the years images like those from the Hubble have helped set standards for color accuracy. Over time the high-end astrophotographers that fall into the "pro" category have also fine tuned and helped to set the standards of how objects we image should look. Knowing what we know and more importantly don't know about space, there's always going to be a degree of doubt on what we perceive to be accurate. So we rely on what we know now and have for reference, striving to match that is what I do.

FROM A SOLAR SYSTEM PERSPECTIVE:
The sun-drenched Lunar surface has until recent years been depicted as an almost grayscale objects as Ron mentioned. The lack of color in this case is not due to faint light but rather the amount of pigment. In recent years the arrival of saturation-enhanced Lunar images offers a fresh look at the Moon. I find it very interesting to see the saturated renditions that reveal the various colors we cannot see regardless of the devices or filters we use. Traditional?, no but interesting and educational. Producing a Lunar image that is color enhanced to make it other than true to its content moves it from astrophotogaphy into astro illustration in my opinion. It doesn't make it any less a photograph, it's just not true to the data collected as are the traditional and saturated methods.

I agree Steve with your statement and maybe you just say it better than me only in a longer more pro way where i say things in a short simple way hoping everyone understands but i'm learning they don't .

--------------------


As far as cameras go, from what I've been able to gather this site does not prohibit the use of non-Canon cameras. Also, POTN is not owned by Canon the corporation. This thread covers both points:
http://photography-on-the.net/forum/showthread.php?t=606953&highlight=canon+sponsor+potn


I did not know this and perhaps the name Canon Forum should be removed ?? This was the only reason i mentioned we should keep this section to Canon cameras .

Many people using dedicated astro CCD cameras started out using DSLRs. They may not fall into the majority here but they still bring a lot of knowledge to the table. Their current work using a dedicated astro camera offers insight and inspiration for those that will follow the same path one day.

I have no objection to the use of non-Canon cameras. I'm concerned most about whether or not the image presented by a member is a means to others learning or advancing their skills. Show me a sculpture and I won't ask which brand chisel you used. I'm more concerned about how you did it, how long it took, etc., etc. I hope that we won't lose sight of the fact that we are fortunate to have a place here at POTN for sharing, learning and enjoying this hobby in a diverse forum.

I haven't noticed anyone posting web cam images but the best planetary images I've ever seen (outside NASA) were taken using web cams. I don't shoot planetary but someone starting out that does would benefit from someone's posts that elaborate on the methods used. Again . . . sharing, learning and fun.

I'm aware and agree with this last part about the webcams . I have seen their work since the first time i heard of the Philips webcam 740k which took possibly the VERY BEST planet images EVER and Philips could have doubled their cost or tripled the cost and made a killing but they chose to retire the 740k and come out with a 840k and so forth but never again to produce the same quality images as the 740k . And as you say with quote : "sharing , learning and fun"....... , i believe i also mentioned keep posting and have fun ! Thanks Steve for your comments , i knew you would eventually get involved here ;) !

[SteveInNZ]

Sorry you disagree Steve , it's your right to . BTW did you notice how i've commented on your images you posted here ? I noticed your moon mosaics were pretty much original and i also commented there . Did i perhaps comment in the wrong way . i'm not sure ?? Perhaps if they were solid purple would i have commented differently , i'm not sure ? But the ones you did post were great including your DSO image .

No need to be sorry, any more than I may have one sugar with my coffee and you may prefer two. Simply different tastes. Just sharing my view which in this case, differs from yours.
Since you mention those mosaics - I entered one of them in a landscape photo contest and despite having mountains and a sea, the arty-farty judge said it didn't qualify.

Steve.

[chris.bailey]

Ron,

My point was that even amongst respected Astrophotographers there is a degree of interpretation. Take these three image of Messier 42

http://ollypenrice.smugmug.com/Photography/astronomy/lesgrangesastrophotos1/10818447_ogKjJ#754460731_neWK5-A-LB

http://i.telegraph.co.uk/telegraph/multimedia/archive/01372/abstract_1372994i.jpg

http://www.astropix.com/HTML/SHOWCASE/M42.HTM

~quite a variation in colour interpretation between them but each has its merits.

In one of Noel Carbonis articles, even he suggests there are no absolute hard and fast rules and a lot of his images have a degree of artistic licence as to what looks good for him. His processing tools even include the ability to add false star spikes, whats that if it isnt dressing up reality as art?

I myself have struggled to get correct debayer colour offset settings for my Cooled OSC CCD and have had wildy different values from authoratative sources which yield markedly differing end results.

As I said I agree with your sentiment but would counter that with the need to have some latitude in what is considered as honest.

Clear Skies

Chris

[Celestron]

Ron,

My point was that even amongst respected Astrophotographers there is a degree of interpretation. Take these three image of Messier 42

http://ollypenrice.smugmug.com/Photography/astronomy/lesgrangesastrophotos1/10818447_ogKjJ#754460731_neWK5-A-LB

http://i.telegraph.co.uk/telegraph/multimedia/archive/01372/abstract_1372994i.jpg

http://www.astropix.com/HTML/SHOWCASE/M42.HTM

~quite a variation in colour interpretation between them but each has its merits.





Chris


I give up trying to explain my OP . All 3 links you provided has a degree shade of red as i mentioned above that M42 would have some degree of red in it . These are not far off to extremes of color degrading or changing as i have explained above as matter of fact i have seen all 3 and know they are what has been provided and accepted by the astronomy class since they were first posted . Have a great day Chris ! .

[hollis_f]

no human can see color beyond a few miles into space unless it's an airplane flying overhead and you see the bright color blinking lights

Or Mars, or the GRS (or should that be the GSDSOGS - Great Slightly Different Shade of Grey Spot) or many stars. Even M42 through a bright scope with dark skies looks green and purple.

[Celestron]

Or Mars, or the GRS (or should that be the GSDSOGS - Great Slightly Different Shade of Grey Spot) or many stars. Even M42 through a bright scope with dark skies looks green and purple.


In a bright scope if M42 looks green or purple to you then you better check your optics , It's probably CA caused by the optics :lol: . However in binos' , scopes or whatever object you look trhrought to see space objects ....., your still not using a naked eye ....... :eyes:smile::idea:

[hollis_f]

In a bright scope if M42 looks green or purple to you then you better check your optics , It's probably CA caused by the optics

Or it could be because the human eye is much more sensitive to green than it is to red. Here's an image (http://www.astropix.com/HTML/SHOW_DIG/TRAPEZIUM.HTM) that's very similar to what I see, although I see it as being a smidge greener than this.

This is using one of the scopes at COAA - and I doubt they have problems with their optics.

[Celestron]

Or it could be because the human eye is much more sensitive to green than it is to red. Here's an image (http://www.astropix.com/HTML/SHOW_DIG/TRAPEZIUM.HTM) that's very similar to what I see, although I see it as being a smidge greener than this.

This is using one of the scopes at COAA - and I doubt they have problems with their optics.


Must be some excellent optics . I have a Celestron C8 and i have detected slight faint greenish hue while observing M42 in a 32mm Plossi EP without a barlow and only on nights that were very good seeing between midnight and 2:00am . I've never detected purple hue at anytime . However i still stand to my quote above , your not looking at M42 with the naked eye and seeing color . Your using an optic device and that optic device is projecting an image to the EP or camera you are visually looking throught or at . If an EP the image is a matter of an inch or two from your eye plain and a camera or screen is a matter of a few inches from your eye plain . Take away those devices and put you in say a bortle scale dark sky at even 8-9 you will see M42 better with the naked eye and you should be able to see M31 very well including the outskirts of the galaxie , BUT you still will not see color in any of those objects with the naked eye .

[Nighthound]

Frank and Ron, you've raised another variable to this astro visual equation. No two sets of eyes are the same nor are the brain centers that interpret the color signals. Even if we were seeing the exact same color, how we each read the color may vary.

Since the subject has moved to color perception I thought these were interesting reads:

http://www.cambridgeincolour.com/tutorials/color-perception.htm

http://www.cambridgeincolour.com/tutorials/camera-sensors.htm

[Bernoulli]

This discussion is getting fun.

The reason we humans see as we do comes from the needs of our ancestors. As far as color goes, we are trichromats (seeing in three color bands) because our tree-living predecessors had the need to distinguish between mature (bad) and immature (tasty) leaves for dinner. This discrimination is most easily made in the red-green area and that's one place we have good color distinction.

On the other hand, Sophie, who is pictured in my avatar on to the left, never had ancestors with this need and can only see in two bands. She's a dichromat and she has the typical canine red-green color blindness compared to us. But what she loses in color sensing she makes up for in vision in dim light. I don't think she would consider herself disadvantaged. But she does see the world very differently from us.

So my philosophical point is, should we hold evolution against us? I don't mind the camera expanding my vision either in resolution, light-gathering power or color balance.

I can only imagine what Soph could see if she looked into the eyepiece of a big dob pointed at the Trapezium!

[chris.bailey]

I then must have shunned the needs of my ancestors as I never ever see leaves as being a tasty dinner :-)

[Celestron]

I give up trying to explain my OP . All 3 links you provided has a degree shade of red as i mentioned above that M42 would have some degree of red in it . These are not far off to extremes of color degrading or changing as i have explained above as matter of fact i have seen all 3 and know they are what has been provided and accepted by the astronomy class since they were first posted . Have a great day Chris ! .



I KNEW I SHOULD HAVE STOPPED HERE !!

[SteveInNZ]

I KNEW I SHOULD HAVE STOPPED HERE !!

:D You've gotta love the internet - What started as a dislike for artificial coloring is evolving into "do vegetarians make better astrophotgraphers". ;)

Steve.

[Bernoulli]

I then must have shunned the needs of my ancestors as I never ever see leaves as being a tasty dinner :-)

I find that red/green receptor to be handy when selecting wines.