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Old Jul 14, 2011, 01:59 PM   #76
mtbdudex
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Originally Posted by soLoredd View Post
Awesome work, mtbdude. You've inspired me to give this a shot soon (work is crazy right now). I really love the startrails.

Have you found a workflow that is OS X-only or are Windows apps still needed? I don't really want to shell out for a copy of Windows.
I gave up trying to find MacOSX stuff for stacking , like Deep Sky Stacker, or making Star Trails...........and in the astro forums every 2-3 months I see that Q asked.

But, with Mac's at 10% market share and rising maybe just maybe the authors of those WinTel programs will port them over.

For now, its a pain; I have to import from SD card to aperture, (for organization), I add keywords in aperture to organize the shots (lights/darks/flats/etc), export as TIFF into organized folders, then start up VMFusion, under windows access those folders, copy those to my WinXP desktop (can't access them correctly if tried to do across the OS's), run the WinTel programs, save to the MacOS desktop, import into Aperture....and upload to web hosting site.

whew, I got tired typing all the "excess" workflow.
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Old Jul 14, 2011, 02:07 PM   #77
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I haven't used it, but give this app a shot. I plan on trying it when I shoot some star trails.

http://www.markus-enzweiler.de/software/software.html
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Old Jul 14, 2011, 03:50 PM   #78
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I haven't used it, but give this app a shot. I plan on trying it when I shoot some star trails.

http://www.markus-enzweiler.de/software/software.html
ding-ding-ding! you get 3 gold stars for this find, definitley I'll try it out.

Heck, I have existing images that I can try it out to compare to the WinTel StarTrails program, http://www.startrails.de/html/software.html

Intresting both of them come from .de domain, kinda makes you wonder if there is some connection or not.

The WinTel version has NOT been updated since
05/30/2005: Version 1.1 (- minor changes)
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Old Jul 18, 2011, 01:51 AM   #79
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...Finally, another bonus nebula I see here? What is the name of this?
(faintly seen Bottom LH)
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Originally Posted by budman1961 View Post
The elusive Horsehead!
No, that's not the Horsehead. It's the Flame Nebula (NGC 2024), the Horsehead would appear below that bright star that is nearest to mtbdudex's "bonus nebula." The Flame nebula is surprisingly bright (photographically) and it shows up in a lot of the photos I take of the constellation Orion.

Here is a link to a picture that will identify both the Flame nebula and the Horsehead.

http://www.eso.org/public/images/eso0949k/

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Old Jul 18, 2011, 02:20 AM   #80
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I gave up trying to find MacOSX stuff for stacking , like Deep Sky Stacker, or making Star Trails...........and in the astro forums every 2-3 months I see that Q asked...
Keith's Image Stacker ( http://keithwiley.com/software/keithsImageStacker.shtml ) works on Mac OS X. However, I've never gotten very good results with that software's auto-alignment feature, but it does work well for stacking the images and for dark frame removal. The UI/control methods are a little difficult to grasp (for me anyway) but Keith has documented the software pretty well so I'd recommend that others at least give it a try. One other limitation, it can't handle images above a certain size, so worse case you may have to downsize your original images before you can stack them (I think the limit in the dimensions works out to something around 10M pixels per image -- not that small but less than some of the more recent DSLRs).

in any case, I'd like to compliment mtbdudex on his photos of M31 and the crescent moon with earthshine. Nice work, it's really amazing how good the night sky images are getting with the latest DSLRs (and given competent work by the photographer).
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Old Jul 18, 2011, 08:03 PM   #81
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Keith's Image Stacker ( http://keithwiley.com/software/keithsImageStacker.shtml ) works on Mac OS X. However, I've never gotten very good results with that software's auto-alignment feature, but it does work well for stacking the images and for dark frame removal. The UI/control methods are a little difficult to grasp (for me anyway) but Keith has documented the software pretty well so I'd recommend that others at least give it a try. One other limitation, it can't handle images above a certain size, so worse case you may have to downsize your original images before you can stack them (I think the limit in the dimensions works out to something around 10M pixels per image -- not that small but less than some of the more recent DSLRs).

in any case, I'd like to compliment mtbdudex on his photos of M31 and the crescent moon with earthshine. Nice work, it's really amazing how good the night sky images are getting with the latest DSLRs (and given competent work by the photographer).
Thx, its been a fun and learning journey.
Until you do more than jiust reada bout techniques, yuou truly don't learn and grasp the details.

Check this out, I just read about this little company called Pentax and their technology that might change how some astrophotography shots are taken.

Could get rid of the usage for barn door trackers or the simple eq mounts for DSLR's with lens.
I still see eq mounts for "real" telescopes.

Cool tech stuff.
http://www.dpreview.com/news/1106/11060310pentaxgps.asp
Quote:
2. ASTROTRACER for effortless astronomical photography
When mounted on the PENTAX K-5 or K-r camera body, the O-GPS1 also offers the advanced ASTROTRACER function,** which couples the unit with the camera’s SR (Shake Reduction) system and enables users to photograph celestial bodies. The unit can calculate the movement of stars, planets, and other bodies using the latitude obtained from GPS data and the camera’s alignment data (horizontal and vertical inclinations and aspect) obtained from its magnetic and acceleration sensors, then shifts the camera’s image sensor in synchronization with the movement of the objects.*** As a result, stars and other bodies are captured as solid points rather than blurry streaks, even during extended exposures. This is the ideal tool for those interested in astronomy and it makes taking images much simpler, as it eliminates the need for additional accessories such as equatorial telescopes.
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Old Jul 18, 2011, 08:07 PM   #82
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ding-ding-ding! you get 3 gold stars for this find, definitley I'll try it out.

Heck, I have existing images that I can try it out to compare to the WinTel StarTrails program, http://www.startrails.de/html/software.html

Intresting both of them come from .de domain, kinda makes you wonder if there is some connection or not.

The WinTel version has NOT been updated since
05/30/2005: Version 1.1 (- minor changes)
Just thought I'd mention that I'm a COMPLETE n00b at astrophotography and I only use a Mac with OSX at the moment, and that I just tried out the StarStaX program linked here for OSX.

For my very first ever attempt at star trails, I shot a whopping five frames at 2am this morning on my front porch, 70 degrees F, using my Nikon D7000, 35mm prime 1.8G@ f/2.0, 10 second exposures, ISO 100. I also shot four dark frames using lens cap, and no bias frames. (I think that's what you call the frames of light with a t-shirt over the lens, right?)

I installed StarStaX and processed them using the standard setup ("lighten") and got this result:

First, I'm blown away that the stars moved that much in just about one minute. I had no idea! The exposures went ten seconds, with about two or three seconds between exposures. I set it up with the built-in intervalometer on the camera, and hopefully I can get tighter intervals between exposures next time. Also, I wanted to see how ISO 100 worked as far as noise, etc. I'm thinking if I go with a higher ISO and exposures of maybe one or two seconds, I can get less of the dashed line effect on the star trails.

I have to say, I'm immediately hooked on this. I expected to have no stars show up at all, and totally trashy light pollution... not to mention how bright the moon was. I mean, there are obviously streetlamps on my block and everything, and I was just being totally lazy to try out the software. I cannot wait to head out to Moab, UT or outside of Leadville, CO to get some really dark skies and see what I can get!

Sorry to be such a goof... I'm just really excited.
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Wait a second... So you're telling me anything that happens in the sky is legal, and there's a giant crime-blimp flying around this place? I don't know how I missed that.

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Old Jul 18, 2011, 08:58 PM   #83
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Just thought I'd mention that I'm a COMPLETE n00b at astrophotography and I only use a Mac with OSX at the moment, and that I just tried out the StarStaX program linked here for OSX.

For my very first ever attempt at star trails, I shot a whopping five frames at 2am this morning on my front porch, 70 degrees F, using my Nikon D7000, 35mm prime 1.8G@ f/2.0, 10 second exposures, ISO 100. I also shot four dark frames using lens cap, and no bias frames. (I think that's what you call the frames of light with a t-shirt over the lens, right?)

I installed StarStaX and processed them using the standard setup ("lighten") and got this result:
Suburbia

First, I'm blown away that the stars moved that much in just about one minute. I had no idea! The exposures went ten seconds, with about two or three seconds between exposures. I set it up with the built-in intervalometer on the camera, and hopefully I can get tighter intervals between exposures next time. Also, I wanted to see how ISO 100 worked as far as noise, etc. I'm thinking if I go with a higher ISO and exposures of maybe one or two seconds, I can get less of the dashed line effect on the star trails.

I have to say, I'm immediately hooked on this. I expected to have no stars show up at all, and totally trashy light pollution... not to mention how bright the moon was. I mean, there are obviously streetlamps on my block and everything, and I was just being totally lazy to try out the software. I cannot wait to head out to Moab, UT or outside of Leadville, CO to get some really dark skies and see what I can get!

Sorry to be such a goof... I'm just really excited.
careful, you'll have red-eyes from lack of sleep....nice first attempt.

btw, once you have say 25-30 minutes of images put them into this free Mac OsX program for time lapse video of the stars moving
http://www.dayofthenewdan.com/projec...se-assembler-1
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Old Jul 18, 2011, 09:04 PM   #84
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Thanks!
I'm thinking the StarStaX software isn't going to help me get those shots like you have, with the ISS moving across the sky, but leaving the stars still. I was expecting the stars to be pretty much still (and thus just enhanced) in my first attempt, but it looks like I'd need to align the stars manually in Photoshop, and keep the image filled with sky only, no landscape... right? The Dark Sky software (DSS) does the alignment, does it not?
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Old Jul 19, 2011, 02:18 AM   #85
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As a follow-up on the identification of the Horsehead versus Flame nebula in Orion here is a badly over processed stack of images that clearly shows the Flame nebula just above and to the left of the leftmost star in Orion's belt (upper left third of image). You can clearly see the dark lane that bisects the Flame nebula. There is, however, no real hint of the Horsehead nebula.

Toward the bottom center of the image you can see a very overexposed white "blob" surrounded by some purple and blue haze the center of which is M42 (the Great Orion Nebula). Immediately above M42 are some bright stars with a blue haze and that is NGC 1973, 1975, and 1977 (sometimes called the Running Man Nebula).

This detail came from a stack of 16 images taken with a Nikon D300 using a 50mm prime lens at f/2. Each image was exposed for 4 seconds and the camera sensitivity was set to ISO 6400. The tonality in this image was stretched almost beyond the breaking point, but I did that just to highlight the Flame Nebula (i.e. I don't consider this a good example of deep sky image processing).
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Old Jul 19, 2011, 02:56 PM   #86
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If I'm going to stack wide-angle images, how do I figure out the optimal number of images and exposure times? That is- what's the difference between 20 2m and 40 1m images going to reveal? Are there minimums and maximums I should be shooting for? How do I figure my base exposure- do I shoot for the ambient conditions, or will stacking take care of that?

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Old Jul 19, 2011, 04:18 PM   #87
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If I'm going to stack wide-angle images, how do I figure out the optimal number of images and exposure times?...Paul
For wide-angle images I use stacking just to avoid having to use a guided exposure on an equatorial mount. Thus, the longest single exposure that I can use for a stack is determined by how much star/object movement I can tolerate in the captured image. That limit varies by the focal length of the lens and the area of sky that you are capturing (longer exposures are possible near the celestial poles, shorter are required near to the celestial equator -- i.e. zero degrees declination). This tolerance also depends upon the final scale that you plan on viewing the image.

For a normal lens (i.e. 50mm on a full-frame 35mm camera or about 35mm on an APS-C digital format) I'd say you shouldn't go much beyond 6 seconds if you want an image that shows little to no movement in the stars (as a general rule for images taken near to the celestial equator, longer exposures are possible nearer to the poles). However, you can go much longer than that if you plan on viewing the final image at a fairly small scale (at smaller viewing scales 10 to 15 seconds would probably still be okay).

Obviously, however, if you plan on guiding your exposure then the above limits on exposure time are changed. In that case, you will be using stacking mainly to reduce the amount of noise that will appear in your final image (and, perhaps, to help eliminate any tracking errors that could occur during long exposures). Stacking also helps to improve the dynamic range or effective contrast in your final image (signal-to-noise ratio).

The next question is what ISO setting to use and here there is a lot of variability. Generally speaking you don't want to use the highest ISO setting that your camera supports. The problem with the very highest ISO settings is noise (obviously) but you can also run into problems from city lights which can "fog" your high-ISO exposures pretty quickly. You can only determine the limits of your camera's ISO setting through testing under the same conditions of dark sky (or not) that you will be imaging. When photographing under very dark skies I usually capture my wide-field images anywhere from one to two stops down from the highest ISO setting.

Lastly, the lens aperture will also affect the quality of your image and how long you can expose. I usually stay pretty close to wide open on the lens aperture although to get better star images you may want to go down by about two full f-stops (this will depend somewhat on the maximum aperture setting on your lens, relatively "slow" zoom lenses may need to be left close to their maximum -- wide-open -- setting while fast, prime lenses can probably be stopped down to improve the image quality while still capturing plenty of light).
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Old Jul 19, 2011, 04:44 PM   #88
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For wide-angle images I use stacking just to avoid having to use a guided exposure on an equatorial mount. Thus, the longest single exposure that I can use for a stack is determined by how much star/object movement I can tolerate in the captured image. That limit varies by the focal length of the lens and the area of sky that you are capturing (longer exposures are possible near the celestial poles, shorter are required near to the celestial equator -- i.e. zero degrees declination). This tolerance also depends upon the final scale that you plan on viewing the image.

For a normal lens (i.e. 50mm on a full-frame 35mm camera or about 35mm on an APS-C digital format) I'd say you shouldn't go much beyond 6 seconds if you want an image that shows little to no movement in the stars (as a general rule for images taken near to the celestial equator, longer exposures are possible nearer to the poles). However, you can go much longer than that if you plan on viewing the final image at a fairly small scale (at smaller viewing scales 10 to 15 seconds would probably still be okay).

Obviously, however, if you plan on guiding your exposure then the above limits on exposure time are changed. In that case, you will be using stacking mainly to reduce the amount of noise that will appear in your final image (and, perhaps, to help eliminate any tracking errors that could occur during long exposures). Stacking also helps to improve the dynamic range or effective contrast in your final image (signal-to-noise ratio).

The next question is what ISO setting to use and here there is a lot of variability. Generally speaking you don't want to use the highest ISO setting that your camera supports. The problem with the very highest ISO settings is noise (obviously) but you can also run into problems from city lights which can "fog" your high-ISO exposures pretty quickly. You can only determine the limits of your camera's ISO setting through testing under the same conditions of dark sky (or not) that you will be imaging. When photographing under very dark skies I usually capture my wide-field images anywhere from one to two stops down from the highest ISO setting.

Lastly, the lens aperture will also affect the quality of your image and how long you can expose. I usually stay pretty close to wide open on the lens aperture although to get better star images you may want to go down by about two full f-stops (this will depend somewhat on the maximum aperture setting on your lens, relatively "slow" zoom lenses may need to be left close to their maximum -- wide-open -- setting while fast, prime lenses can probably be stopped down to improve the image quality while still capturing plenty of light).
Ok- that's starting to help- let's say I was going to shoot with a 50mm f/1.8 at ISO 800, can I just stack a bunch of six second exposures, or am I still constrained by exposure somehow? I'm not sure how the stacking affects exposure I guess- my intent is to hit Cherry Springs, which is a dark sky site, but I'm still trying to figure out if I'll get good results without an equatorial mount or at the least building a barn door hinge mount.

Is there a formula for exposure? Google gets me a few guidelines, but no hard rules.

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Old Jul 19, 2011, 08:27 PM   #89
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Top 10 in 2010 to shoot (Astronomy, non telescope)

Sharing here, I collected these shots over the course of 1+ year in 2010.
Originally posted @ Canon P.O.T.N Top 10 in 2010 to shoot (Astronomy, non telescope)

From that thread
Quote:
With your help I'd like to make a to do list for 2010, call it the "Top 10 in 2010" related to astronomy.

This would be for people with DSLR, tripod, at least a lens up to 200mm, etc, but without telescope.
(I don't have one, and no $$$$'s for one this year)

Just for ref my gear: T1i, kit lens 18-55 & 55-250, 50 1.4, tripod, remote.

Purpose is general neat/cool shots of the moon and cosmos, and to learn about the moon/cosmos AND photography techniques (image stacking, PP, etc).
I'd like to involve my 3 kids to whatever extent I can to encourage their appetite for space.
Therefore I've consolidated the responses from that thread into below
(thx members Bernoulli, chris.bailey, siriusdogstar, Celestron, Adrena1in, SteveInNZ, troypiggo, xs5875, CalPiker, Jeff, 67champ ).

You've help make my 2010 assignment list, thx people.

I'll continue talk about success/failures/learning/technique here, post photos in the photo forum.

Top 10 in 2010 to shoot (Astronomy, non telescope); underline links to the posts in the photo sharing section.
Green = done, Orange = expected, Red = missed.
1. Full Moon; zoom lens; T1i + 55-250 kit @ 250mm Moon shots: 70-200 f2.8 L mkII + 1.4x + 2.0x TC's stacked
560 via 70-200 + 2x + 1.4x TC


2. Moon at various Phases; put 7-9 images into photo collage
3. Lunar X; zoom lens; images here
3a Lunar "X" challenge thread , 3b Lunar "X" on the wanning??
3c "X" 11/13 16:13 EST, 21:13 UTC


4. Moon illuminated by Earthshine ; zoom lens Moon by earthshine

5. Creative moon shots; Moonrise over lake /clouds; wide lens
...5a "spider web" around the moon....

5b moonrise over the tree line , 5c Moon reflection window & ISS + STS-131 streaking
5d Full moon in clouds

5e Full Moon a rising over the lake..Oct 22, 2010
6. total lunar eclipse Dec 20/21 http://en.wikipedia.org/wiki/Decembe..._lunar_eclipse ; Cloudy with a chance of meatballs was the weather Total Lunar Eclipse / Solstice
7. ISS, Space Shuttle, Iridium Flares ;wide lens, long exposures; try zoom on ISS (my 250mm lens not enough reach); images here
7a ISS + STS 131 tomorrow morning..(4/9 6am EDT)
7b July-4-2010 ISS captured (six 20 sec exposures)
7c Oct 20, 2010 Iridium 56 -6mag

7d ISS taken 10-26-2010 (4) 25 sec exposures @ 15mm
[edit: topics 8-11 moved to post #2 ]

Studies done:
a) Exposure time to see where image movement becomes visible for 50mm and 85mm lens (considering cropping the image); my conclusion 50mm good for 8 sec and 85mm good for 5 sec, some CA study done also

b) Tip on are clouds present in atmosphere for moon shots http://photography-on-the.net/forum/showthread.php?p=12614828#post12614828

Resources used:
Baz's To help you with star trails and stacking
Troy's Get your astro software here

Tip on focus camera with live view:
I've had luck with live view, 10x, then manual focus until the brightest star you can find gets small/sharp as possible.
Sometimes that takes a back/forth on the focus ring until you find that center spot of focus.
Even if you have to crank up the ISO just to focus to show the star brightrest, then move it down for the actual shot.
Infinity marking on lens is a good start, but that varies on temp and zoom.
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Old Jul 19, 2011, 08:28 PM   #90
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Top 10 in 2010 to shoot (Astronomy, non telescope) - cont

added posts #8 - 11 to this post for 144pix preview images

8. Star Trails ; wide lens, long exposures, stacking; images here
8a Loghome star trail (my 1st)
8b Geminid meteor shower night & Star Trails

8c South/North star trails from this weekend (Fri/Sat 2-4-2011)
9. Milky Way/Orion-M42/M31-Andromeda ; wide lens, long exposures, stacking; images here
9a Shooting the Milky Way: C&C for success strategies

9b Milky way, star trails @ Northern Shore Lodge , 9c M31/Andromeda DSS 57 frames @ 10 sec, 85mm
9d M31/T1i/50mm/f1.4/via DSS

9e Orion/M42 via T1i/50mm lens/DSS

9f Orion/M42 via T1i/DSS @ 85mm
10. Meteor Showers; Lyrids Apr 22 , Perseids Aug 12/13, Geminids 12/14; wide lens; long exposures, stacking
10a Perseid meteor shot Tues 8/10 (caught 2) , 10b Aug 13, 2010 Perseid meteor's - captured 4
10c Geminid meteor shower
11. Jupiter and 4 moons ; 11a Jupiter and 4 moons (thx BlakeG! and GuitarFreak) late Thur Aug 26
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Old Jul 19, 2011, 08:29 PM   #91
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Ok- that's starting to help- let's say I was going to shoot with a 50mm f/1.8 at ISO 800, can I just stack a bunch of six second exposures, or am I still constrained by exposure somehow? I'm not sure how the stacking affects exposure I guess- my intent is to hit Cherry Springs, which is a dark sky site, but I'm still trying to figure out if I'll get good results without an equatorial mount or at the least building a barn door hinge mount.

Is there a formula for exposure? Google gets me a few guidelines, but no hard rules.

Paul
Paul;
Look at my studies a) I posted above, I experimented and got some results should help you.
from that post
Quote:
If I'm doing Astrophotography with 50mm lens in general I'd shoot up to 8 sec exposure IF I was going to also crop the full image (my T1i 15MP 4752 x 3178 image) to 1024 wide, if not then 10 or even 13 second may suffice, depends on how much "sky"/object you want to show in the crop.

Simple math for 85mm lens.
If I say 8 sec "works" for 50 mm lens can I do 50mm/85mm times 8 sec = 4.7 sec so 5 sec would be "my equivalent" acceptable for 85mm lens based on above.
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Old Jul 19, 2011, 09:20 PM   #92
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Originally Posted by compuwar View Post
Ok- that's starting to help- let's say I was going to shoot with a 50mm f/1.8 at ISO 800, can I just stack a bunch of six second exposures, or am I still constrained by exposure somehow? I'm not sure how the stacking affects exposure I guess- my intent is to hit Cherry Springs, which is a dark sky site, but I'm still trying to figure out if I'll get good results without an equatorial mount or at the least building a barn door hinge mount.

Is there a formula for exposure? Google gets me a few guidelines, but no hard rules.

Paul
The maximum total exposure (number of stacked images) is probably limited more by your patience than anything else. However, I doubt that you'll see much improvement once you go past 16 images (for wide-field star images, other rules apply for planetary work). From my experience it's hard to see much change unless you at least double the number of images in the stack. Thus, once at 16 you might have to go well beyond 32 images before you'd see a notable change. It also depends upon what you want to capture. If you just want to record stars then an eight image stack would be more than adequate. However, if you want to record nebula or the fainter portions of the Milky Way then you'll probably need more.

However, even with only 16 images in a stack, and depending upon your base exposure (ISO, aperture, single-frame exposure time) it's possible to overexpose on some of the brighter nebula. Just look at the image I posted of M42 -- it's badly overexposed, the nebula is just a white blob (it is also slightly out of focus, one of the problems when trying to use an AF lens which has no hard-stop for infinity focus).

Last edited by fpnc; Jul 19, 2011 at 09:29 PM. Reason: Added comment about focus
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Old Jul 22, 2011, 11:17 AM   #93
mtbdudex
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Location: SE Michigan
lots of fireflies & star trail (2+ hrs images)

I meant to capture about 45-55 minutes of 20 second exposures 2 days ago 10:40pm - 11:30pm, but fell asleep, woke up 3am.....and went outside to retrive the set-up.
The T1i battery had died, even though hot night the dew point was enough below the actual temp the lens stayed clear.

specs:
T1i + 15-85 @ 15mm, each 20 sec exposure, over 370 images, just over 2 hrs of images.
Captured as RAW, import into Aperture 3, no PP whatsoever, just export as TIFF for StarStax to make startrails. All done in Mac OsX.

The moon rose around 12:30am, and its reflection is seen in the 2 garage windows as it ascended.


Made a 15 second video clip
you can see the moonrise in the garage lower RH and upper middle window.
This video is between 10:45pm and 1am.

Link to YouTube HD 720p version, select 720p to see detail in the video clip:
(once you start it select the 360p and pull up to 720p.)


btw, anybody know how to link to YouTubeHD directly?
Other forums you simply add "HD" to the [you.tube]youtube#[/you.tube], like this[youtubeHD]youtube#[/youtubeHD] .
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Old Jul 22, 2011, 01:18 PM   #94
Deako
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Absolutely love this thread. I wish i didn't live in a light polluted area of Birmingham in the UK.

Have you managed to carry out any testing with StarStax yet?
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Old Jul 22, 2011, 05:50 PM   #95
Keleko
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Moon in the morning behind some thin clouds. 220mm, f/5.6, 1/80s


Cloudy Morning Moon by Gerg1967, on Flickr
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Old Jul 24, 2011, 05:37 PM   #96
fpnc
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Went out early this morning to capture the waning crescent moon and I noticed that the planet Jupiter was visible in the same area of the sky so I tried a few quick captures of the planet with my "lowly" 72mm aperture Astro-Tech telescope. The original single exposures even captured the four Galilean moons which I've labeled in this seven image stack.


Jupiter and Galilean Moons Additional details are available on Flickr.

Last edited by fpnc; Jul 24, 2011 at 10:00 PM. Reason: Added link to improved image on Flickr
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Old Jul 26, 2011, 04:56 AM   #97
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After my modest "success" with Jupiter I thought I would try some shots of Saturn this evening. I knew it would be tough because I calculated that I'd need about 4 more stops of exposure to compensate for the relative dimness of Saturn and to allow for greater magnification (since Saturn's planetary disk is quite a bit smaller than Jupiter's). I also didn't have very good observing conditions as Saturn is getting pretty low in the western sky and I didn't begin my session as early in the evening as I should have. Well, so much for the excuses.

You can see (faintly) the shadow of Saturn's rings on the planet's surface and perhaps just a hint of some duskiness on the upper (northern?) hemisphere. I'm certain that the slight break on the outer edge of the rings is NOT the Cassini division, I think it's just an artifact from the image processing.

Astro-Tech AT72ED using afocal projection with a 10mm eyepiece coupled to a 50mm prime lens on a Nikon D5100 (ISO 1600 at 1/15s -- stack of four images).
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Old Jul 27, 2011, 09:10 AM   #98
budman1961
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A few nebulas.....

I finally moved into the guiding world, here is the result! M17 the Omega Nebula, M20 the Trifid Nebula, and M27 the Dumbbell Nebula.

All were take with my Meade LX200 Classic 10" f6.3, Canon 1000D, no barlows or tricks. Exposures from 2 to 6 minutes (M20), 10 frames each. Enjoy!
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Old Jul 27, 2011, 02:34 PM   #99
fpnc
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Quote:
Originally Posted by budman1961 View Post
I finally moved into the guiding world, here is the result! M17 the Omega Nebula, M20 the Trifid Nebula, and M27 the Dumbbell Nebula.

All were take with my Meade LX200 Classic 10" f6.3, Canon 1000D, no barlows or tricks. Exposures from 2 to 6 minutes (M20), 10 frames each. Enjoy!
I can still remember the first time I saw a color image of the Trifid Nebula when I visited the 200" Palomar Observatory. I was amazed by the beauty and striking colors. Equally amazing is that now even amateur astronomers can take pictures that nearly rival what could be done on the Palomar telescopes back in the days before digital imaging and adaptive optics.
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Old Jul 27, 2011, 03:10 PM   #100
grooveattack
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also in the photo of the day thread
Taken at 3am while i couldn't sleep.
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