Approve the Cookies
This website uses cookies to improve your user experience. By using this site, you agree to our use of cookies. Read More.
OK
Index  •   • New posts  •   • RTAT  •   • 'Best of'  •   • Gallery  •   • Gear  •   • Reviews
New posts  •   • RTAT  •   • 'Best of'  •   • Gallery  •   • Gear  •   • Reviews
Register to forums    Log in

 
FORUMS Photo Sharing & Visual Enjoyment Astronomy & Celestial
Thread started 27 Oct 2010 (Wednesday) 15:45
Prev/next
sponsored links
(this ad will go away when you log in as registered member)

You don't need a telescope

 
Pagman
I just hold the thing :-)
Pagman's Avatar
Joined Dec 2011
Nov 12, 2017 19:54 |  #2146

MalVeauX wrote in post #18495004 (external link)
Finding a DSO requires navigation (degrees, etc). It's easier starting out to simply star hop. Find your DSO in stellarium. See what stars are near it that you can identify easily and quickly. Use them as guide points to get where you want to be. Depends how dark your skies are too. I can find Andromeda with my naked eye just looking up, but I'm under fairly dark skies. On my short scope (400mm), I use a laser pointer that is aligned with the scope to point it in the direction of an object I want to look at it quickly put it on it. Eventually you learn the sky and you can easily move from object to object based on common stars (like constellations).

Ex, here I'm pointing my laser at M42 before I move to my scope to look through as they're aligned. But I can literally see M42 with my naked eye, along with M31, so it's easier.

QUOTED IMAGE
[IMAGE'S LINK: https://flic.kr/p/RjL6​Ln] (external link)ST80_GreenLaser (external link) by Martin Wise (external link), on Flickr

Very best,


Sincerely Thank you martin for all your help, its a facinating hobby and without your help, it would be a nightmare working my way through it.

P.


Nikon D7100, Nikkor 300 f4 IF ED :-)

LOG IN TO REPLY
sponsored links
(this ad will go away when you log in as registered member)
Tareq
"I am very lazy, a normal consumer"
Tareq's Avatar
17,693 posts
Gallery: 2 photos
Joined Jan 2006
Ajman - UAE
Post has been edited 28 days ago by Tareq.
Nov 13, 2017 04:31 |  #2147

Astronomy or astrophotography became an addicted hobby for me this year, i spent a lot so far and still spending, but now i am stopping as my budget is suffering so i will continue next year.

I learnt with Stellarium and i bought one very simple cheap book in Arabic about the sky, this helped me a lot about finding DSO, i kept looking at popular targets or objects, searched them via stellarium and i see which constellation each are within then i go out to find the stars that i can recognize in each constellation, i look at brighter stars ofcourse, i live in a heavy light pollution, but i could manage to find targets even if i can't see them with naked eyes or even with my binocular and scope.

Now i am focusing more about my equipment and about techniques for getting images for stacking then processing, i already completely the set of software i can use in astrophotography, and later i hope to finish/complete my set of equipment too, i have something now that i can use for a while then i will see what i need later.

Talking about that M45 in this thread, so you have 140 frames for stacking, each frame is 1 second, that is translated into 2 minutes and 20 seconds, then what about a single frame or exposure that is 3 minutes or even 5 minutes? what if i take frames of about 10-15 and each frame is only 2 minutes? So if i have more frames to stack it will be better than a single frame same exposure long of the stacked ones?

Should i try to upload PNG files of a target i am taking and someone here can check out how good it is?

I am using filters, one i already have, and other filters i ordered and waiting them soon i hope.


Galleries:
http://hamrani.deviant​art.com/gallery/external link
Gear List
Facebookexternal link

LOG IN TO REPLY
J-Blake
Great Googley Moogley!
J-Blake's Avatar
Joined Dec 2009
Westminster, CO
Nov 13, 2017 07:52 |  #2148

MalVeauX wrote in post #18495004 (external link)
Finding a DSO requires navigation (degrees, etc). It's easier starting out to simply star hop. Find your DSO in stellarium. See what stars are near it that you can identify easily and quickly. Use them as guide points to get where you want to be. Depends how dark your skies are too. I can find Andromeda with my naked eye just looking up, but I'm under fairly dark skies. On my short scope (400mm), I use a laser pointer that is aligned with the scope to point it in the direction of an object I want to look at it quickly put it on it. Eventually you learn the sky and you can easily move from object to object based on common stars (like constellations).

Ex, here I'm pointing my laser at M42 before I move to my scope to look through as they're aligned. But I can literally see M42 with my naked eye, along with M31 (not in the same part of the sky, but easy to spot with naked eye), so it's easier.

QUOTED IMAGE
[IMAGE'S LINK: https://flic.kr/p/RjL6​Ln] (external link)ST80_GreenLaser (external link) by Martin Wise (external link), on Flickr

Very best,

Martin, I've been reading you're recent posts helping Pagman with his quest and have to extend a big thank you for detailing your process. I have marked this section for return later to go through all the great information you're sharing. I've wanted to try shots like this and felt I was not geared properly, but you've opened my eyes. Thanks for taking the time and sharing!


Jon
So much to learn, so little time.
A few worthy shotsexternal link

LOG IN TO REPLY
Tyguy
Senior Member
Tyguy's Avatar
Joined Sep 2014
Calgary, Canada
Nov 21, 2017 11:28 |  #2149

Pagman wrote in post #18494965 (external link)
I added anoter 100 or so frames at 1sec f4 Iso 6400 last night as there was a clear winters sky, I stacked them with my previous ones and ended up with about 140 stacked lights.
I worked on the final Tiff in both PS2 and LR5 here is my best so far.

P.

I'm impressed that you did this without tracking. Bravo!

A tracking mount would be very beneficial. Most DIY tracking mounts are motor driven and require some knowledge of robotics to build. There are simpler ones which are hand-cranked, basically two pieces of wood, a hinge, and some threaded rod.


-Tyler
flickr (external link)

LOG IN TO REPLY
Pagman
I just hold the thing :-)
Pagman's Avatar
Joined Dec 2011
Nov 24, 2017 16:44 |  #2150

Had another go outside in the cold tonight, I couldn't find Andromeda (still) despite searching with my camera and 300mm lens, in all the right places, perhaps its just not dark enough here.
Anyway what I did get was this - its 20 x 1 sec frames at Iso 6400 and f4.

P.

HOSTED PHOTO
please log in to view hosted photos in full size.

Nikon D7100, Nikkor 300 f4 IF ED :-)

LOG IN TO REPLY
MalVeauX
"Looks rough and well used"
MalVeauX's Avatar
Joined Feb 2013
Florida
Post has been edited 17 days ago by MalVeauX.
Nov 24, 2017 16:55 |  #2151

Pagman wrote in post #18503427 (external link)
Had another go outside in the cold tonight, I couldn't find Andromeda (still) despite searching with my camera and 300mm lens, in all the right places, perhaps its just not dark enough here.
Anyway what I did get was this - its 20 x 1 sec frames at Iso 6400 and f4.

P.

If you have another, wider lens, you could use that to find Andromeda first. Center it up. Then switch to the 300. It will be hard to put a 300mm, both on full frame or APS-C, on Andromeda without any means other than exposing and seeing if it's there.

Another method to get you there is to align a laser pointer to your lens (like the photo I posted a bit ago). Then, just use guide stars to get into the general area where Andromeda should be, like someone posted for you, and use the laser pointer to ensure you're pointed at the right area, then expose with your lens and see where you are. Should be right on it, or close enough to know where to go from there. Cheap laser pointer will do the job, nothing fancy, you just have to mount it to your system and align it to the lens. Save you a ton of time. Give your eyes time to adjust to the dark, 30 minutes should do, then scan for guide stars and orient yourself to where M31 should be, the general area, and use your peripheral vision to look for a feint fuzzy bright patch, that will be M31.

You probably won't get enough exposure at 1 second, F4 ISO 6400 to see the surrounding galaxy, but you should at least see the core of Andromeda and a glow around it.

Very best,


My Flickr (external link) :: My Astrobin (external link) :: Canon 17-40L For Sale

LOG IN TO REPLY
andicus
Member
196 posts
Joined Aug 2009
Post has been last edited 17 days ago by andicus. 3 edits done in total.
Nov 24, 2017 17:03 |  #2152

I used Astrometry.net to plate solve your image. You're up near Cassiopeia.

You can see your image superimposed in the WorldWide Telescope, here:

http://www.worldwidete​lescope.org ...rometry.net/image/4​188064 (external link)

Sorry for the giant link, but this forum doesn't allow TinyURL links.

If you haven't used WorldWide Telescope before, you can drag to scroll, and mouse wheel to zoom in and out.

You can see M31 about 3 or so fields below your image.

Hope this helps!


Canon EOS 7D, EOS Digital Rebel XTi / EOS 400D / Kiss Digital X | Canon EF 50mm f/1.4 USM, EF 70-200mm f/2.8L USM, EF-S 55-250mm f/4-5.6 IS |

LOG IN TO REPLY
MalVeauX
"Looks rough and well used"
MalVeauX's Avatar
Joined Feb 2013
Florida
Nov 24, 2017 17:19 |  #2153

Tareq wrote in post #18495196 (external link)
Talking about that M45 in this thread, so you have 140 frames for stacking, each frame is 1 second, that is translated into 2 minutes and 20 seconds, then what about a single frame or exposure that is 3 minutes or even 5 minutes? what if i take frames of about 10-15 and each frame is only 2 minutes? So if i have more frames to stack it will be better than a single frame same exposure long of the stacked ones?.

Quality of signal is important, so a longer exposure time will yield more signal than a shorter exposure time will. Stacking simply reduces random noise and keeps constant signal. But if your signal is already really weak, it's not going to get stronger, it's just not going be lost as noise. As the noise is reduced, the signal to the noise's ratio becomes more favorable to the signal.

You simply cannot get much signal from a 1 second exposure compared to a longer exposure (on the order of several minutes). There are extreme imagers who do capture 2~3 second exposures of feint galaxies, and stack them, but they're stacking on the order of several thousand images to achieve it, not just a few or even a hundred (and generally are using small sensor USB cameras, not dSLR's, and especially take advantage of monochrome sensors).

You will get far more out of a 2 minute exposure, 10~15 of them, than even 120 exposures of 1 second. Again, the number of images being stacked primarily reduces random noise. But to get better signal and more of it, you simply need to expose longer.

Bottom line: expose for as long as your system can tolerate. Get more higher quality signal. Get lots of them if you can. I'd rather have 30 x 3~4 minute exposures than 1,000 x 5 second exposures.

++++++++++

For example, here's a single 3 minute exposure at F6 and ISO 800. You can see the flame nebula pretty well on its own from just this one single non-processed non-stacked exposure (this is literally unprocessed beyond converting to JPG). You can see the feint outline of the Horse Head nebula too to the right of it. Just an outline really. And it's surrounded with dust other trails, but you can't really see those here from this single exposure.

Single exposure, 180 seconds, F6, ISO 800:

HOSTED PHOTO
please log in to view hosted photos in full size.

Here's the stack of 37 x 180 seconds, or 111 minutes, just a little shy of two hours of exposure time with the histogram stretched and some minor processing:

IMAGE: https://farm1.staticflickr.com/458/32116881900_7aaff6e996_c.jpg
[IMAGE'S LINK: https://flic.kr/p/QW4q​47] (external link)FlameHorseHead_0123201​7 (external link) by Martin Wise (external link), on Flickr

And here's the same data after extensive processing to pull out all the data in the near-2-hours of signal that was captured (the dust primarily around the nebula that I wanted to extract). Because as always, there's rarely ever truly black space out there, with enough signal you'll find there's dust every where.

IMAGE: https://farm1.staticflickr.com/568/31911833773_e5290d605c_c.jpg
[IMAGE'S LINK: https://flic.kr/p/QBWu​oz] (external link)FlameHorseHead_ReProc_​01232017 (external link) by Martin Wise (external link), on Flickr

Very best,

My Flickr (external link) :: My Astrobin (external link) :: Canon 17-40L For Sale

LOG IN TO REPLY
Pagman
I just hold the thing :-)
Pagman's Avatar
Joined Dec 2011
Nov 24, 2017 18:40 |  #2154

I used Stellarium and had it open as a guide befor I set up outside (cam/tripod/chair) I used the large box of stars at Pegasus as a guide then moves along to my left (UK alignment) counting three stars including the last one in the box, then went a little way up as shown on stella, as I couldn't see anything with my cam (even starting off using my VF) I decided to set it up on the tripod and get it braced aswel as possible (the head on my tripod tends to make the weight of my cam/lens move even when tightened up as tight as my hand can), so I let the adjustment handle drop and trap against the top of the legs support.
Then it was just a matter of using the 10sec self timmer - using the shutt button and wait a moment a second before each frame.

P.


Nikon D7100, Nikkor 300 f4 IF ED :-)

LOG IN TO REPLY
Unbalanced
As one of the gluttons for punishment, I'm glad to see Chet's back
Unbalanced's Avatar
Joined Nov 2009
Colorado
Nov 24, 2017 19:42 |  #2155

MalVeauX wrote in post #18503448 (external link)
Quality of signal is important, so a longer exposure time will yield more signal than a shorter exposure time will. Stacking simply reduces random noise and keeps constant signal. But if your signal is already really weak, it's not going to get stronger, it's just not going be lost as noise. As the noise is reduced, the signal to the noise's ratio becomes more favorable to the signal.

You simply cannot get much signal from a 1 second exposure compared to a longer exposure (on the order of several minutes). There are extreme imagers who do capture 2~3 second exposures of feint galaxies, and stack them, but they're stacking on the order of several thousand images to achieve it, not just a few or even a hundred (and generally are using small sensor USB cameras, not dSLR's, and especially take advantage of monochrome sensors).

You will get far more out of a 2 minute exposure, 10~15 of them, than even 120 exposures of 1 second. Again, the number of images being stacked primarily reduces random noise. But to get better signal and more of it, you simply need to expose longer.

Bottom line: expose for as long as your system can tolerate. Get more higher quality signal. Get lots of them if you can. I'd rather have 30 x 3~4 minute exposures than 1,000 x 5 second exposures.

++++++++++

For example, here's a single 3 minute exposure at F6 and ISO 800. You can see the flame nebula pretty well on its own from just this one single non-processed non-stacked exposure (this is literally unprocessed beyond converting to JPG). You can see the feint outline of the Horse Head nebula too to the right of it. Just an outline really. And it's surrounded with dust other trails, but you can't really see those here from this single exposure.

Single exposure, 180 seconds, F6, ISO 800:

thumbnailHosted photo: posted by MalVeauX in
./showthread.php?p=185​03448&i=i90532755
forum: Astronomy & Celestial

Here's the stack of 37 x 180 seconds, or 111 minutes, just a little shy of two hours of exposure time with the histogram stretched and some minor processing:

QUOTED IMAGE
[IMAGE'S LINK: https://flic.kr/p/QW4q​47] (external link)FlameHorseHead_0123201​7 (external link) by Martin Wise (external link), on Flickr

And here's the same data after extensive processing to pull out all the data in the near-2-hours of signal that was captured (the dust primarily around the nebula that I wanted to extract). Because as always, there's rarely ever truly black space out there, with enough signal you'll find there's dust every where.

QUOTED IMAGE
[IMAGE'S LINK: https://flic.kr/p/QBWu​oz] (external link)FlameHorseHead_ReProc_​01232017 (external link) by Martin Wise (external link), on Flickr

Very best,

^^^^^^^

~THIS~ is awesome!

Thank you Mr. Wise.

Slowly amassing my setup. I so want to do this.

I appreciate all of the info you've shared.

Quick question: When you say 'extensive processing', what kind of time do you have in that image? It is killer, by the way. :-)


The crux of the biscuit is the apostrophe.
flickr (external link)

LOG IN TO REPLY
MalVeauX
"Looks rough and well used"
MalVeauX's Avatar
Joined Feb 2013
Florida
Nov 24, 2017 19:52 |  #2156

Unbalanced wrote in post #18503509 (external link)
^^^^^^^

Quick question: When you say 'extensive processing', what kind of time do you have in that image? It is killer, by the way. :-)

I say extensive because if you take into account the time for stacking, producing a final stacked image to further process, then start processing it, it will likely take at least 60 minutes total time realistically unless you have a workflow down. The reason is, you have to actually measure carefully the image to find the levels and curves values that you're going to push/pull which are unique to the image. Basically I can process all my images in about an hour or so.

I used the above examples because they literally were created using near-exactly the step by step processes in order of that video tutorial I linked (on how to process RGB dSLR images). That video is saved to my computer and when I process a DSO, I open that video and watch each segment, pause, do it, watch, pause, do it (for the parts in software I have that apply to what I'm doing).

A lot of the processing is subtle and subjective, so you do a lot of "on" and "off" with layers to see the difference.

But those three links I posted before hand, those alone are all you need to go from having a camera to producing great DSO images.

Very best,


My Flickr (external link) :: My Astrobin (external link) :: Canon 17-40L For Sale

LOG IN TO REPLY
Unbalanced
As one of the gluttons for punishment, I'm glad to see Chet's back
Unbalanced's Avatar
Joined Nov 2009
Colorado
Nov 24, 2017 22:26 as a reply to MalVeauX's post |  #2157

Thank you, my friend.

I hope to be able to work up something that nice.

It may be a while, but I'll certainly post 'em up.


The crux of the biscuit is the apostrophe.
flickr (external link)

LOG IN TO REPLY
Davenn
Senior Member
Davenn's Avatar
Joined Jun 2013
Sydney, Australia
Nov 25, 2017 02:55 |  #2158

Pagman wrote in post #18503427 (external link)
Had another go outside in the cold tonight, I couldn't find Andromeda (still) despite searching with my camera and 300mm lens, in all the right places, ...............
P.

unfortunately not quite the "right places"

it seems you appear to be getting lost during your star hopping on the way to location
As Andicus said, you are quite some distance away from where you should be

it's all practice buddy :-)
I learned to star hop to objects long before there were home computers, let alone planetarium programs like Stellarium
It is a very good skill to learn and keep in practice :-)


forget the 300mm lens, don't use anything bigger than 100mm and preferably something around 50mm
and practice using that to get you into the right area .... M31 will show up with a 50mm lens
But as Mal said, 1 sec exp's even stacked will be difficult, you need to start getting out to ~ 30 sec exp's stacked


Dave


A picture is worth 1000 words ;)
Canon 5D3, 6D, 700D, a bunch of lenses and other bits, ohhh and some Pentax stuff ;)

LOG IN TO REPLY
Pagman
I just hold the thing :-)
Pagman's Avatar
Joined Dec 2011
Nov 25, 2017 17:17 |  #2159

Davenn wrote in post #18503658 (external link)
unfortunately not quite the "right places"

it seems you appear to be getting lost during your star hopping on the way to location
As Andicus said, you are quite some distance away from where you should be

it's all practice buddy :-)
I learned to star hop to objects long before there were home computers, let alone planetarium programs like Stellarium
It is a very good skill to learn and keep in practice :-)

forget the 300mm lens, don't use anything bigger than 100mm and preferably something around 50mm
and practice using that to get you into the right area .... M31 will show up with a 50mm lens
But as Mal said, 1 sec exp's even stacked will be difficult, you need to start getting out to ~ 30 sec exp's stacked

Dave


Hi dave, I just have the one lens - my 300mm that has to do my different subjects - Bif, Planes and DSO.
Finding where Andomeda should have been was quite easy as I was able to follow and count the path using stars from Pegasus towards Andromeda, then two stars upwards, but as I couldn't see anything I assumed I was in the wrong area, I re tried this several times, but got my camera/lens locked slightly higher and just shot away several frames to see what I might get.

P.


Nikon D7100, Nikkor 300 f4 IF ED :-)

LOG IN TO REPLY
Tareq
"I am very lazy, a normal consumer"
Tareq's Avatar
17,693 posts
Gallery: 2 photos
Joined Jan 2006
Ajman - UAE
Nov 25, 2017 23:54 |  #2160

MalVeauX wrote in post #18503448 (external link)
Quality of signal is important, so a longer exposure time will yield more signal than a shorter exposure time will. Stacking simply reduces random noise and keeps constant signal. But if your signal is already really weak, it's not going to get stronger, it's just not going be lost as noise. As the noise is reduced, the signal to the noise's ratio becomes more favorable to the signal.

You simply cannot get much signal from a 1 second exposure compared to a longer exposure (on the order of several minutes). There are extreme imagers who do capture 2~3 second exposures of feint galaxies, and stack them, but they're stacking on the order of several thousand images to achieve it, not just a few or even a hundred (and generally are using small sensor USB cameras, not dSLR's, and especially take advantage of monochrome sensors).

You will get far more out of a 2 minute exposure, 10~15 of them, than even 120 exposures of 1 second. Again, the number of images being stacked primarily reduces random noise. But to get better signal and more of it, you simply need to expose longer.

Bottom line: expose for as long as your system can tolerate. Get more higher quality signal. Get lots of them if you can. I'd rather have 30 x 3~4 minute exposures than 1,000 x 5 second exposures.

++++++++++

For example, here's a single 3 minute exposure at F6 and ISO 800. You can see the flame nebula pretty well on its own from just this one single non-processed non-stacked exposure (this is literally unprocessed beyond converting to JPG). You can see the feint outline of the Horse Head nebula too to the right of it. Just an outline really. And it's surrounded with dust other trails, but you can't really see those here from this single exposure.

Single exposure, 180 seconds, F6, ISO 800:

thumbnailHosted photo: posted by MalVeauX in
./showthread.php?p=185​03448&i=i90532755
forum: Astronomy & Celestial

Here's the stack of 37 x 180 seconds, or 111 minutes, just a little shy of two hours of exposure time with the histogram stretched and some minor processing:

QUOTED IMAGE
[IMAGE'S LINK: https://flic.kr/p/QW4q​47] (external link)FlameHorseHead_0123201​7 (external link) by Martin Wise (external link), on Flickr

And here's the same data after extensive processing to pull out all the data in the near-2-hours of signal that was captured (the dust primarily around the nebula that I wanted to extract). Because as always, there's rarely ever truly black space out there, with enough signal you'll find there's dust every where.

QUOTED IMAGE
[IMAGE'S LINK: https://flic.kr/p/QBWu​oz] (external link)FlameHorseHead_ReProc_​01232017 (external link) by Martin Wise (external link), on Flickr

Very best,

Thank you very much!

Then i am doing fine, all what i need is to take my time in taking long exposures and subs calibrations so it will help me better in stacking and processing to yield better results.

And about the horse head, i already found out about the exposure needed, i tried in one night with Ha filter for about 5 minutes of a single exposure, i took about 5, i wanted to take more but i stopped immediately because the image has an issue that isn't the exposure, if that issue didn't happen i was going to have enough exposures for stacking, and i wasn't planning to shoot longer than 5 minutes of single exposure regardless it can be done, i was just testing, and happy to see the horse head area even not that much clear, way better than the first image you posted, and it is a mono, but i just want to know how long is long enough, and i feel it is all about that signal noise ratio, as long i have it good then i am all set, and my camera is COOLED, so that also helps.

Can't wait to use my LRGB filters beside Ha and see the results, waiting little more items to keep going.


Galleries:
http://hamrani.deviant​art.com/gallery/external link
Gear List
Facebookexternal link

LOG IN TO REPLY
sponsored links
(this ad will go away when you log in as registered member)

570,758 views & 507 likes for this thread
You don't need a telescope
FORUMS Photo Sharing & Visual Enjoyment Astronomy & Celestial


Not a member yet? Click here to register to the forums.
Registered members get all the features: search, following threads, own gear list and ratings, likes, more forums, private messaging, thread follow, notifications, own gallery, settings, view hosted photos, own reviews and more...


AAA

Send feedback to staff    •   Jump to forum...    •   Rules    •   Index    •   New posts    •   RTAT    •   'Best of'    •   Gallery    •   Gear    •   Reviews    •   Polls

COOKIES DISCLAIMER: This website uses cookies to improve your user experience. By using this site, you agree to our use of cookies. Privacy policy and cookie usage info.

POWERED BY AMASS 1.4version 1.4
made in Finland
by Pekka Saarinen
for photography-on-the.net
Spent 0.00381 for 6 database queries.
PAGE COMPLETED IN 0.09s
Latest registered member is Ishani
771 guests, 328 members online
Simultaneous users record so far is 6430, that happened on Dec 03, 2017