M16--The pillars

[Rodd]

I am always fascinated by this target, and am always surprised just how much focal length it takes to really get close in on the pillars.   This was taken with a 5" scope, so I was not expecting too much.  I know the stars need some work--believe me, they were much worse.  Kind of too late now anyway as I just have the JPEG.  Obviously this is a crop, and at first glance I say Woe--too big on the screen.  But each time I look I end up changing my mind on a down sample and size reduction.  I look the forward to capturing this with the C11--but its not an easy one for me to get--maybe next year.  EDIT: It reduces in size when you click on it.

TOA 130 with ASI 1600

Ha 49 5min

OIII 25 min

SII 25 min

Edited August 4, 2019 by Rodd

[geordie85]

Very nice. It's amazing that they appear so small, yet they're truly massive and dwarf our entire solar system. 

[vlaiv]

Who needs Hubble

PS right click / open in new window on image + click for 1:1 - it is larger than in browser window.

[tomato]

Very impressive,  I would love to give this target a proper go but it’s height above the horizon is always a challenge from my location.

[Rodd]

5 hours ago, geordie85 said:

Very nice. It's amazing that they appear so small, yet they're truly massive and dwarf our entire solar system. 

Thanks Geordie.  If I am not mistaken, I think I read somewhere that the tallest pillar is several light years long.  If that is true--it would stretch all the way to Alpha Centauri....that's amazing.  I can't remember if it was that long or a couple light years.  Either way.....HUGE

Rodd

[Rodd]

5 hours ago, vlaiv said:

Who needs Hubble

PS right click / open in new window on image + click for 1:1 - it is larger than in browser window.

I'll take it if they have no more use for it!!😀

Rodd

[Rodd]

1 hour ago, tomato said:

Very impressive,  I would love to give this target a proper go but it’s height above the horizon is always a challenge from my location.

Thanks Tomato--I kjnow teh feeling.  This and M17. M8 and M20 are that way for me.  I have a very short window.

Rodd

[geordie85]

30 minutes ago, Rodd said:

Thanks Geordie.  If I am not mistaken, I think I read somewhere that the tallest pillar is several light years long.  If that is true--it would stretch all the way to Alpha Centauri....that's amazing.  I can't remember if it was that long or a couple light years.  Either way.....HUGE

Rodd

Yeah, I think I read somewhere that the little nipples you see in the hubble image are the size of our solar system. 

Truely immense 

[MarsG76]

Excellent result.. I find that the pillars were quite small at 2000mm too.. so I'd estimate that 6000-8000mm focal length would be needed to get good detail and a good size of the pillars....

[vlaiv]

8 hours ago, MarsG76 said:

Excellent result.. I find that the pillars were quite small at 2000mm too.. so I'd estimate that 6000-8000mm focal length would be needed to get good detail and a good size of the pillars....

Image Rodd captured is about as good as it gets with amateur setups. Additional focal length is not going to help here as you'll just capture blurred image.

It is very, very hard for amateur setups to get any sort of additional detail below 1"/px. Pillars are some 4'40" high and 2'10" wide. If you sample at 1"/px you'll get their width at about 130px.

Rodd's image is already sampled at somewhere around 0.78"/px (estimate based on quick measurement of distance of two bright top stars), so this is pretty much biggest meaningful rendition of pillars on amateur setups.

[Rodd]

2 hours ago, vlaiv said:

Additional focal length is not going to help here as you'll just capture blurred image.

Not focal length alone, surely---but when I say longer focal length I mean combined with more aperture.  I guess I should have specified this, but I have always considered the native focal length of a scope the upper limit for deep space imaging (as opposed to planetary/lunar/solar).  The focal length of a system can be reduced well enough--but not increased effectively.  They do sell a 1.5x ex5tender for the TOA--but I have always envisioned that being useful for solar system work, either visual or imaging, and not deep space--at least not for my sky.

So, I might agree that for a 1,000mm focal length the image reveals about as much as one can expect--though the processing could certainly be improved...I pushed it pretty hard and there are numerous artifacts.  Also--the image might be a .78 arcsec/pix image, but the seeing was nowhere near this and the FWHM values are nowhere near this.  As I said...no where near diffraction limited performance.

Rodd

[wornish]

This discussion makes me realise I don't know enough about the interaction between all the variables when capturing a deep space images.  Focal Length, Pixel size, pixel scale, viewing, FWHM, diffraction limit etc.

I understand the basics but can't get my head around how each factor interplays.

Is there a post anywhere that explains all of this in relatively easy to understand terms?

[vlaiv]

20 minutes ago, wornish said:

This discussion makes me realise I don't know enough about the interaction between all the variables when capturing a deep space images.  Focal Length, Pixel size, pixel scale, viewing, FWHM, diffraction limit etc.

I understand the basics but can't get my head around how each factor interplays.

Is there a post anywhere that explains all of this in relatively easy to understand terms?

I don't think there is a single post, but there are a lot of posts that debate certain aspects / topics that you mention. I think it's been all covered, but not in the same place, it's scattered over the forums, mostly in Imaging section, so you'll have to do a bit of search, or maybe start a new thread that will put everything in one place?

[Rodd]

3 hours ago, wornish said:

This discussion makes me realise I don't know enough about the interaction between all the variables when capturing a deep space images.  Focal Length, Pixel size, pixel scale, viewing, FWHM, diffraction limit etc.

I understand the basics but can't get my head around how each factor interplays.

Is there a post anywhere that explains all of this in relatively easy to understand terms?

It certainly is difficult to envision how changing the various parameters (pixel size, sensor size, Focal length, resolution etc) in combination will manifest in your image.  Changing one at a time can get expensive.  This "discussion" is what lead me to the FSQ 106 with .6x reducer and ASI 1600 (not used in the above image).  It combined largish FOV, small pixels, fast focal length, higher than normal resolution for the FOV.   Can you imagine taking it a step farther and having a 50100 sensor with 3nm pixels at F3 and a focal length of 400?  It would be like a 10 panel mosaic using a high resolution long focal length rig......or would it.....a complicating factor is how the image is displayed on the computer--is there a resizing that goes on if the FOV is larger than the screen?  hard to figure without experimenting.

Rodd

[wornish]

47 minutes ago, Rodd said:

It certainly is difficult to envision how changing the various parameters (pixel size, sensor size, Focal length, resolution etc) in combination will manifest in your image.  Changing one at a time can get expensive.  This "discussion" is what lead me to the FSQ 106 with .6x reducer and ASI 1600 (not used in the above image).  It combined largish FOV, small pixels, fast focal length, higher than normal resolution for the FOV.   Can you imagine taking it a step farther and having a 50100 sensor with 3nm pixels at F3 and a focal length of 400?  It would be like a 10 panel mosaic using a high resolution long focal length rig......or would it.....a complicating factor is how the image is displayed on the computer--is there a resizing that goes on if the FOV is larger than the screen?  hard to figure without experimenting.

Rodd

Thanks for replying.  I agree.  

I currently have  the Esprit 100ED and the ASI1600MM-Pro camera the combination works well on my AZ-EQ6-GT mount.  Its not a permanent setup so each time I have to go through the polar alignment and guiding stuff before capturing anything.   I am getting better at gathering data and doing post processing. (not  at your level by some way but learning all the time.)

I was considering going for a reflector with more aperture and also longer focal length to capture smaller targets but it is becoming apparent that simply going for that might not give me what I am hoping for.  Not sure the mount can cope with a focal length of say 2350mm, so that would need upgrading.  Then the seeing where I am is not bad but not brilliant either.  So in the end would it be worth it?  

[Rodd]

40 minutes ago, wornish said:

Thanks for replying.  I agree.  

I currently have  the Esprit 100ED and the ASI1600MM-Pro camera the combination works well on my AZ-EQ6-GT mount.  Its not a permanent setup so each time I have to go through the polar alignment and guiding stuff before capturing anything.   I am getting better at gathering data and doing post processing. (not  at your level by some way but learning all the time.)

I was considering going for a reflector with more aperture and also longer focal length to capture smaller targets but it is becoming apparent that simply going for that might not give me what I am hoping for.  Not sure the mount can cope with a focal length of say 2350mm, so that would need upgrading.  Then the seeing where I am is not bad but not brilliant either.  So in the end would it be worth it?  

You also have to consider collimation, which in a reflector could take some time to get used to and depending on the quality of the reflector, for a system that is not permanent, might have to be done frequently.  Be careful...I have learned that aperture fever is a very difficult thing to cure!!!  I have a C11Edge with a .7x reducer--so not F10 (F7) with a FL of 1960--and do you know how much I use it?  Hardly ever.  The FOV is pretty restrictive and my seeing not very good--certainly not good enough to take advantage of the resolution it provides.  Then again, I am lazy and have limited clear sky time, so loosing a night in the switch is something I can't bring myself to do.  Also, I had some trouble with the STT-8300, which is the right camera for the scope, and a switch would require switch cameras and filters as well--a bigger chore for sure.  I have been hankering for the scale it provides though and will be switching to it once I check out the FSQ 106 to make sure the collimation issue has been fixed. 

I will say, do not attempt the reflector unless you are sure your mount can handle it (unless you have the money and the expense is no big deal for you).  Unless, you are also interested in lumar or planetary /solar imaging.  Then I'd say go for it.  With the aperture and a $300 camera you can take a walk on the Moon, or float near the rings of Saturn (rotating planets get complicated though to really do them justice, but the Moon is as easy as it gets).

To end--obtaining another scope can't be bad.....unless you have to get rid of one to obtain it.  then it is a replacement, and that is much more tricky unless you ensure that the whole system is compatible (mount, camera, scope, sky).

Good luck!

Rodd

[tomato]

For me, first and foremost is the mount, it can be seriously under used on forgiving FL set ups but when the focal length increases you can’t do much about guiding performance if your mount isn’t up to it.

Following Olly Penrice’s findings on large refractor/small pixel camera vs large aperture longer FL reflector for imaging smaller targets, I was persuaded to go the former route, with no regrets on the outcome.

But I do like what a large aperture well collimated RC can deliver on small targets, so one thing is for sure, unless you rigorously confine yourself to one type of object to image, this hobby can certainly be money hungry. 💷🔭🙄

Steve

[Rodd]

10 minutes ago, tomato said:

certainly be money hungry. 

More like starved!!!!

Rodd

[MarsG76]

On 05/08/2019 at 19:31, vlaiv said:

Image Rodd captured is about as good as it gets with amateur setups. Additional focal length is not going to help here as you'll just capture blurred image.

It is very, very hard for amateur setups to get any sort of additional detail below 1"/px. Pillars are some 4'40" high and 2'10" wide. If you sample at 1"/px you'll get their width at about 130px.

Rodd's image is already sampled at somewhere around 0.78"/px (estimate based on quick measurement of distance of two bright top stars), so this is pretty much biggest meaningful rendition of pillars on amateur setups.

I've have seen a image of the pillars taken by a fellow in Israel using a 16" RC scope during very dry conditions and obviously optimal seeing/atmospheric conditions, and his result was by far the best I have seen taken by a amateur... It was as close as I have ever seen comparing to the original hubble image..  I'll see if I can find it....

That said, Rodd's image is very excellent and this is most likley at the level where the dryness of the atmosphere will play a bigger role than normally expected.

 

 

[Rodd]

4 hours ago, MarsG76 said:

I've have seen a image of the pillars taken by a fellow in Israel using a 16" RC scope during very dry conditions and obviously optimal seeing/atmospheric conditions, and his result was by far the best I have seen taken by a amateur... It was as close as I have ever seen comparing to the original hubble image..  I'll see if I can find it....

That said, Rodd's image is very excellent and this is most likley at the level where the dryness of the atmosphere will play a bigger role than normally expected.

 

 

I’d say aperture and sky conditions.  A 16 inch scope will reveal, if not more detail (though it will) a........more resolved image. I have seen an image like what you referr to, maybe even the same one and there is no comparison

[vlaiv]

4 hours ago, MarsG76 said:

I've have seen a image of the pillars taken by a fellow in Israel using a 16" RC scope during very dry conditions and obviously optimal seeing/atmospheric conditions, and his result was by far the best I have seen taken by a amateur... It was as close as I have ever seen comparing to the original hubble image..  I'll see if I can find it....

That said, Rodd's image is very excellent and this is most likley at the level where the dryness of the atmosphere will play a bigger role than normally expected.

 

 

I'm sure it has to be really good and resolved image as most things that affect image resolution could have been right:

- enough aperture to provide resolving power

- desert conditions - dry air will minimize scatter (no halos around stars) and seeing was probably very stable (it does tend to be so in flat deserts on particular nights)

- mount used is probably top tier (needs to be high capacity to hold 16" RC scope) and guides very good.

[maw lod qan]

That's incredible.

Makes you wonder what's out there we'll never see?

[Rodd]

1 hour ago, maw lod qan said:

That's incredible.

Makes you wonder what's out there we'll never see?

Many things that we WILL see too.  Take SH2-129 (Flying Bat and Squid).  the squid (OIII) was not discovered until very recently by an amateur.  He thought he would try and see if there was anu OIII emission in the large Ha nebula that had been known for some time.  There sure was.   Finds of this caliber are few and far between--but I bet there are thousands of small planetary nebula and other less extensive objects (funny we call these things deep space objects when they are about as far away from being objects as can be envisioned!) scattered throuhgout the galaxy (and beyonddd!!!)

Rodd