M78

[RichLD]

@CCD Imager - slightly off topic but do you have a gallery or website, I'd love to see your other stuff!

Totally agree with your comments about PS BTW 

[CCD Imager]

Rich, no I don't. I used to have one for many years, but not for the last 3-4 years. I also have a whole bunch of images that I have still to process, bad aren't I!

Visiitng France has re-vitalized me though, so I may be posting more soon

[PatrickGilliland]

17 minutes ago, CCD Imager said:

Paddy, I can't argue with anything you have said. One point about the human eye is that it can distinguish upto 14 stops of light, whereas the best camera's only upto 11 stops (there is some marketing hype around tho!). I can't see camera's matching the dynamic range of our eye anytime soon. But one area we do fail in is with night vision, Our rods are pretty useless and being able to discern colour at a truely dark site is gone. However, the objects we image emit light at certain wavelengths represented by a colour, which  as astrophotographers, we should try to replicate. Currently Astrophotography is all about artistic license to do whatever you want, you can make faint detail bright and vice versa. I have watched the changes over the last 20 years and given that an astrophotographer has done the basics of getting an image at the scope, the highly processed images done by photoshop knowledgeable persons are the most admired around the globe. It is becoming an essential skill of the astrophotographer! I have 3 long standing astrophotographer friends who frown upon this - bodged, slider tweaker, Xmas tree lights and more. I've been called all names  I've tried to explain, but to no avail, I feel they are being left behind. They have excellent kit, great technical knowledge of astronomy, years of experience, yet only do the minimum processing. I sometimes think they are using their lack of photoshop skills as an excuse  OTOH, there are images out there that are glaringly over -processed, like Oxford St at Christmas, that will put off these doubters. My own opinion is to selectively process to make an image look better, but try and retain a sense of reality, You have now seen three I took from France, so you know where I am coming from

Adrian

Hi Adrian - it is interesting to hear of your friends, being left behind or sticking to there guns?  Write or wrong?  I am on board with the issues around doing what you want, this is a no-no i think.  The image must preserve relational integrity at least I try to do that.  Truth told I am a slave to the software though not the science and could be miles of the mark as a result.  I have been very guilty of the over processed path and still have some work to do there at times IMO.  Thought it interesting to assess reality when we still are limited by reality limiting equipment.  A true eye replication as you say could result in poor colourless images if the weaker characteristics prevail in the design.  If we take the stronger ones that provides more of everything but maybe less accuracy.  I think having a style, approach is spot on.  Your approach/style is different to mine and mine is different to others, the joys of the hobby.  But collectively we adhere to gross rules with our fine tweaks.  We should not fear challenging them though from time to time.

Paddy

[CCD Imager]

Paddy, its fair to say they are neither right nor wrong, but they are in a small minority these days and with their under-processed images, will gain few plaudits. Just look at the comments on my "saturated" core off M78 for example. It was already way over-processed  

[PatrickGilliland]

5 minutes ago, CCD Imager said:

Paddy, its fair to say they are neither right nor wrong, but they are in a small minority these days and with their under-processed images, will gain few plaudits. Just look at the comments on my "saturated" core off M78 for example. It was already way over-processed  

Well you have to respect their views then do what you need to do  I do love topics like this, interesting to learn from the views of others and if required adapt my own.  My views change the more I learn, will be interesting to see what they are when I finish my degree (I am still preparing to start that though) in Astronomy.  I already have i-SLoan filter ordered and a cheap spectrograph is on the shopping list, may have access to a space based x-ray scope next year as well.  Be interesting to see how these impact my version of reality.....   

[swag72]

An interesting discussion and one that I didn't quite decide on!! But it did spark an article and it was fun trying to decide what I felt was important and why. I think that all opinions are relevant at the end of the day even if we don't always like or agree on the image and how it's been presented. 

[George 47]

1 hour ago, CCD Imager said:

Paddy, its fair to say they are neither right nor wrong, but they are in a small minority these days and with their under-processed images, will gain few plaudits. Just look at the comments on my "saturated" core off M78 for example. It was already way over-processed  

I tend not to use PS and prefer PI as I sometimes find it easier to think in numbers but that is probably me. PS has a  huge learning curve and if you do not use it often then you forget where the thirteenth slider is positioned in the menu structure.

Keeping away from the extreme ends of the spectrum, Olly raised the more interesting question and that is what do you do with the data you have? If in your data there are arms in a galaxy that are fainter than the core is it a distortion of the data to make them brighter than the core? Is it a distortion if you selectively sharpen a feature you are interested in, but I am not? I am not arguing for bad images but what changes are acceptable and what are not.

And when those changes go to extremes then we are truly becoming artistic and the data was only a start point and reality fades. The boding has then begun.

And no Adrian it has nothing to do with learning the software as 2 of the guys you mention do have a small background in physics, chemistry, maths statistics and I have written professionally used software.....

[CCD Imager]

Precisely George, scientists not artists

[steppenwolf]

Quote

I do not claim to be right in anything I have said (firmly on the fence  ) but feel until such time we have a camera pointing at the skies that really can emulate the capability of the human eye

I enjoyed your discourse, Paddy! I don't think that such a camera will ever become available because a lot of the colour that we see is within the mind and has a variable relationship to the physical characteristics of the light's wavelength. Ambient lighting conditions play a part in our perception of light too although I guess this aspect could be incorporated in such a camera.

My own take on right and wrong is pretty simple really:-

1. Anything goes if it satisfies the imager providing:-

    nothing celestial is removed to enhance the image

    nothing that doesn't exist in the raw data is added to enhance the image

2. Never include someone else's data unless agreed by the originator and clearly identified as such in the image.

I enjoyed Sara's article in AN and it is a subject that Sara and I have discussed before as it has played on her mind since producing some fascinating Ha only full colour images. I do think that it is important to qualify how an image has been produced to prevent a false 'truth' from being generated by an image. Unfortunately, once in the public domain, it is difficult to ensure that this integrity is maintained by others but that is not the same as saying that such images shouldn't be produced kin the first place!

[swag72]

1 hour ago, CCD Imager said:

Precisely George, scientists not artists

So you have no time for the artists? Not being inflammatory...... genuinely interested in your view

[PatrickGilliland]

45 minutes ago, steppenwolf said:

I don't think that such a camera will ever become available

Agreed not in our lifetimes or budgets anyway!  Technology will improve, there is a upper limit to resolution of 130mp (I think) beyond that the eye won't be able to see it. Off the topic a little for moment: CCD have progressed slower than Moore's transistor law but they will get to this limit I suspect in the next decade.  Features such as HDR are already available, not sure how this works and if true or pseudo but these are the areas the R&D will shift to once the maximum resolution limit is approached.  Of course other factors come into play for AP cameras.  130Mp is just part of the issue the the µm size would have to be compatible with popular scope sizes.  In AP I suspect this will provide bigger chips (not a bad thing) but if done via smaller µm size it could soon become a problem.  The R&D budgets for AP will always be relatively low but if there was a bottomless pot a intelligent camera capable of initially reviewing its brightness and saturation for the given sub length, which then adjust its gain to a pre-defined threshold (say 90% well depth).  This would benefit also from the higher well depth charge capacities.  I see there are some research spectroscopy cameras (small chips and large µm though) with well depths > 500K.  A 8300 size chip with intellisense sub length would be pretty good I suspect.  With that sort of well depth and saturation based review capability I bet you could easily create HDR based parameters. EG discharge well X by Y if well Y is > n(X).   

1 hour ago, steppenwolf said:

Never include someone else's data unless agreed by the originator and clearly identified as such in the image.

Had not picked up picked up on this point?  I read it as an area was artificially created (Which i think would fail your point 1.2) .  If the earlier permission is a prerequisite of course, for both I would like declaration of what has been done.  I often create L detail through manipulation of RGB and small stretches, reapplying back to the L data if anything is found.  It's all in the data so don't see it as false data but I will declare as some may consider it to be an untrue representation of the object.  I don't mind if they do, in fact being up front about it may attract less positive feedback, in many cases though it's only the fact I declare it that makes it known to anyone.  This is a good example of working the existing data in a different way and maybe challenging the accepted approaches and boundaries.  Not artificially creating it, just finding in different places.  Recent publication seem to validate the approach but i still declare even this minor fact on how I obtained from the data in an alternate way.  Agree on false truth's, creating something that is not there I do not find appealing and as Sara points out it may verge on irresponsible why?  When we image something it is like a second dimension to the look back time.  As we see it now will never be replicated.  If I look back at something I imaged with a lookback time of .3 last year the actual look back time has to time coordinates.  Ones which will never be replicated.  Imagine Beetlejuice goes  SN in 3 months time and you want a reference image of the star and the local proximity.  A false representation of the 2D co-ords could lead to inaccurate research.  I for one think as 'amatuer' AP improves it will be more and more for science based observations that the limited number of pro scopes can not cover.  

Anyway enough rambling for today - of to do something constructive and take my son to watch 'Rogue One'  

Paddy

[CCD Imager]

1 hour ago, swag72 said:

So you have no time for the artists? Not being inflammatory...... genuinely interested in your view

I thought my comment might be construed as bias against scientists! I have spent areas of my working life as a scientist and also as an artist, so no bias towards either group. In fact I think its sometimes difficult for a scientist to have an artists instinct in life and vice versa. Like others here, I am neither fully against an artistic approach to imaging and understand the shouts from scientists bending good original data.

[CCD Imager]

Its a good job that camera's are lacking in area's of QE, resolution and dynamic range. A perfect camera would result in us all producing the same image with no processing needed!! 

[ollypenrice]

14 hours ago, CCD Imager said:

Its a good job that camera's are lacking in area's of QE, resolution and dynamic range. A perfect camera would result in us all producing the same image with no processing needed!! 

Now that's a very good point indeed!

Olly

[andrew s]

23 hours ago, CCD Imager said:

Its a good job that camera's are lacking in area's of QE, resolution and dynamic range. A perfect camera would result in us all producing the same image with no processing needed!!

I am not sure this is true. It is certainly true that an unprocessed image contains the most information available in the image. But and it is a big but we are not capable of seeing all the subtleties in the data captured by even a perfect linear detector with our visual system. We need to process the data to bring it out. 

For me valid processing just reveals things in the data in a way we can appreciate - e.g. false colour. while invalid processing adds artifacts not in the original data e.g. de-convolution halos.

However, for me artistic images can have any processing the creator of the image desires as long as they are happy with the result.

Regards Andrew