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NeGRit0

macrumors 6502a
Apr 19, 2008
941
185
Las Vegas, Nv

NeGRit0

macrumors 6502a
Apr 19, 2008
941
185
Las Vegas, Nv
Anyone want to try this out a good opportunity is coming up.

http://science.nasa.gov/science-news/science-at-nasa/2010/05aug_perseids/

With this, does anyone know if it matters what part of the world you are in? it says look northeast around midnight when its changing from aug 12th to aug 13th, but no mention of a particular time zone or anything like that. I would really hate to miss this opportunity, and any help or thoughts are greatly appreciated.

Found my answer on this site... list best times for almost anywhere in the world. Good luck to all! =o)

http://www.tabwin.com/perseids/
 

joepunk

macrumors 68030
Aug 5, 2004
2,553
13
a profane existence
Cool, thanks for the site even though it doesn't have much info for Washington State. I really want to try to see this meteor shower but dread having to travel an hour or two away from any city/town light pollution.
 

NeGRit0

macrumors 6502a
Apr 19, 2008
941
185
Las Vegas, Nv
Cool, thanks for the site even though it doesn't have much info for Washington State. I really want to try to see this meteor shower but dread having to travel an hour or two away from any city/town light pollution.

I live in Vegas, so i feel your pain. I'm driving about an hour an a half away and up a mountain. This will be my first time even seeing a meteor shower, I'm stoked for this.
 

mtbdudex

macrumors 68030
Original poster
Aug 28, 2007
2,670
4,116
SE Michigan
Talk about luck and timing!
I just came back from 4 day vacation in northern part of Michigan's lower peninsula, Hillman, about 1 hr south of Mackinac bridge.
This was a test shot Tues Aug 10th of Milky Way multiple exposure I was preparing for, as the 20 sec exposure went off I saw these 2 streaks and hoped they were in my field of view.

YES! For orientation, north (Polaris) is Top/Left and just off this field of view, south is sorta bottom/RH.
This is single image shot with 15-85 @ 15mm, ISO 800, f 3.5, no stacking.
_MG_1153%20-%20Version%202.jpg


Definitely active skies, in the 35 minutes I was shooting saw 9 meteorites, 1 brilliant with flower trail.
Good luck with clear skies and capturing some.
Dark skies (and no light pollution) helps.
I went outside just now here in SE Michigan, hoping to set-up camera for some images, too hazy skies so processing all the images from vacation (instead of sleeping).
 

paulg

macrumors member
Mar 18, 2004
36
0
UK
I really want to capture this but just looked at the weather forecast.
Cloudy rainy England.
I look forward to seeing the more fortunate people's images.
good luck
p
 

joepunk

macrumors 68030
Aug 5, 2004
2,553
13
a profane existence
Talk about luck and timing!...

YES! For orientation, north (Polaris) is Top/Left and just off this field of view, south is sorta bottom/RH.
This is single image shot with 15-85 @ 15mm, ISO 800, f 3.5, no stacking.

Definitely active skies, in the 35 minutes I was shooting saw 9 meteorites, 1 brilliant with flower trail.

Very cool
 

mtbdudex

macrumors 68030
Original poster
Aug 28, 2007
2,670
4,116
SE Michigan
Nice, I'm gunna see what I can get tonight. As a general rule of thumb for astrophotography, what are good apertures and ISO's to use for say, 20 second exposures?

for wide field astrophotography:

as a start:
Manual mode
wb = daylight
ISO =800 (more than that and you get sensor noise issues except on newest models like 7d)
aperture = as wide as you can get! Gather all that light
how wide? I shoot @ 15mm wide on my 15-85 lens, I've heard too wide (say 10mm) and shorter meteorite streaks don't get captured often or hard to distinguish
focus = set to infinity (different techniques to achieve)

take a test shot at 20 sec & 25 sec, see how light pollution makes your picture "glow" at horizon, go from there. More than 25 sec and you'll see star trails to begin.

If you "stack" then need to take dark frames.
(there are whole tutorials on stacking.....)

enjoy!
 

mtbdudex

macrumors 68030
Original poster
Aug 28, 2007
2,670
4,116
SE Michigan
Milky way, star trails @ Northern Shore Lodge, Hillman Mich Aug 8 - 11 2010

From 8/8-8/11 vacation at the Northern shore lodge Hillman Michigan, http://northernshorelodge.com/index.htm

All these shots are single exposures except the star trails.
For the Milky way shots, I did take multiple shots for DSS later this weekend, will be interesting to compare the added depth/clarity DSS gives vs single exposure shown below.
I'll post those in this thread as they are done.

#1: Lodge @ night, 25 sec exposure:
_MG_0885.jpg


#2: Aug 8 star trail-lodge, same framing as prior, just stacked (75) 20 second exposures. You can see some whispy clouds caused gaps in star trails.:
Aug%208%20star%20trail-lodge.jpg


#3: Milky way due south with Ess lake shoreline, this is single 30 sec exposure, you can see whispy clouds here:
_MG_0651.jpg


#4: Another single 30 sec exposure due south on Ess lake side, this showing more of Milky way with trees just on LH lower side, still slight clouds.
_MG_0656.jpg


#5: This is Long lake side, another single 30 sec exposure, almost North slight east view of Milky way, tree on RH side for reference.
_MG_0846.jpg


#6: One of my favorite shots from this nightime series, this is Long lake side, I like this shot as is....30 second exposure captured some ligh pollution even way up north.
_MG_1148.jpg


#7: Another Long lake side shot, 30 sec exposure
_MG_1151.jpg


#8: The Milky way directly overhead from Long lake side, it darker there than by the lodge.
_MG_1156.jpg


Like I stated at start of this post, for the Milky way shots I did take multiple shots for DSS later this weekend, will be interesting to compare the added depth/clarity DSS gives vs single exposure shown above.
I'll post those in this thread as they are done.
 

mtbdudex

macrumors 68030
Original poster
Aug 28, 2007
2,670
4,116
SE Michigan
I've identified 4 meteorites so far in my shots, for 3+ hours effort..... I saw more but not in my lens field of view.
Dew set in at 3:45 am-ish while I was in the home processing other astrophotography photos from prior shooting sessions, came out to check and had to wipe the lens, seemed the lens would stay clear only 9-12 minutes before moisture built up on it again.
I gave up at 5:30am-ish just as early morning dawn was peaking.
Went back to bed, got 75 minutes more of sleep, had to go to work.

Will post the "keepers" this weekend after some PP.

When I was up north darker skies led to much more prominent meteorite trails than the 4 I captured this morning, and I live in sorta rural / countryside area, not exactly suburbs.

fwiw, next time I'd try ISO 1600 to capture the less bright streaks better
 

NeGRit0

macrumors 6502a
Apr 19, 2008
941
185
Las Vegas, Nv
No meteors, but more trails....




Exif Info:
Camera Canon EOS Digital Rebel XTi
Exposure 20 min
Aperture f/5.6
Focal Length 18 mm
ISO Speed 100
 

joepunk

macrumors 68030
Aug 5, 2004
2,553
13
a profane existence
Mukilteo Light House Beach Park Area, WA
Nikon D50, used my 28mm f/2 and zenitar 16mm f/2.8 fisheye

@30 sec. ASA400

Saw some meteors but non in the camera field of view. Went back home after the park bench and I got wet from sprinklers. To much light pollution for longer exposers.
 

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NeGRit0

macrumors 6502a
Apr 19, 2008
941
185
Las Vegas, Nv
Mukilteo Light House Beach Park Area, WA
Nikon D50, used my 28mm f/2 and zenitar 16mm f/2.8 fisheye

@30 sec. ASA400

Saw some meteors but non in the camera field of view. Went back home after the park bench and I got wet from sprinklers. To much light pollution for longer exposers.

Not bad. If you use a shorter exposure you could get star points, as opposed to the slight dashes...
 

Carnivor

macrumors regular
Feb 24, 2008
217
0
Ok, I live in a very light polluted area of the UK, and am very jealous of some of the sky qualities in the pics so far, So anyway, I thought i'd chip in....

I've been experimenting with star trails as part of my astrophotography hobby.

I use various PC apps to assemble what I capture through the SLR, and the SLR attached to my Newtonian Reflector. There are a few good free ones around, but you have to try what your after in each app to find which produces the best results.


So Pic 1, This is a 100 frames stacked image, the advantage being you can use short exposures (8s) and combine them to enhance what the eye can't at first see. (that will make sence on pic 2), but for this pic I havent done that.


Startrails.jpg


As you see, you get the star trail effect (excuse the break in the lines thats where clouds went past and I had to drop the frames, it also explains the photoshop effect you see on the right hand side, also the adjacent line is IIS going over ( that was my original target) and you can see the dotted lines which are aircraft)

So onto pic 2, the same set of 100 pictures, but this time i've opted to stack the stars by aligning them, eliminating (mostly) the rotation.

Notice how the terrible streetlight glow almost disappears and the amount of detail in the sky is dramatically improved.

Starsaligned.jpg


You also get to experience how much the planet spins rather than the stars rotate.

The next pair of pics are the same 2 processes but i've managed to get an arty farty leaf in with the pole star. It was a clearer night for it!

Startrails2_2.jpg


110Stars%20Aligned.jpg


All this was done with just a Nikon P5100 pocket digital camera, set to take pics 8s each every 10 seconds. I can only get 110 odd pics out of it in 1 battery, and some clever free software.

http://www.astronomie.be/registax/index.html

http://deepskystacker.free.fr/english/index.html

Most of it is windows software im afraid, but I also use Starry Night Pro Plus 6 on the mac for my planning. I can connect my scope to it and it will track objects etc, with my D60 connected to the scope you can get right in there!! Focus then becomes the issue, as you connect the scope directly to the camera body and cant see sod all though the viewfinder so its a bit hit and miss.

So far i've discovered this is a very difficult form of photography....

M92-2.jpg


But M92 didn't come out to badly I suppose...
 

mtbdudex

macrumors 68030
Original poster
Aug 28, 2007
2,670
4,116
SE Michigan
Ok, I live in a very light polluted area of the UK, and am very jealous of some of the sky qualities in the pics so far, So anyway, I thought i'd chip in....


But M92 didn't come out to badly I suppose...

Carnivor, I like everything you are doing and showing, thx for sharing.
Good fun stuff.
 

mtbdudex

macrumors 68030
Original poster
Aug 28, 2007
2,670
4,116
SE Michigan
M31/Andromeda DSS 57 frames @ 10 sec, 85mm

Located M31, this is 1 of many test shots took @ 15mm trying to center it onto the frame. Centered above the peak of our home.
_MG_3742.jpg


Then as I had almost centered, went to take a shot at 50mm, this effect happened....lens creep!
That what happens when you shoot almost straight up.
Kinda cool, almost Star Trek looking...
_MG_3744.jpg


Here is my DSS output from those shots taken Wed 9/15 @ 5am in the morning, I'm excited at 1st capture of M31, not sure what to make of the "quality" of this capture.
Seems at 85mm lens 10 sec is slightly too much, star trailing shows somewhat, I'd try 6 second exposures next time.
57 light images shot with my 15-85 lens @ 85mm, 1600 ISO, 10 seconds each + 10 dark frames
10%20sec%20RAW.jpg


cropped shows the stars as "egg shape" instead of point star due to sky rotation, I'm wondering if M31 would show more clarity at 6 seconds.
(I had 2 airplanes in these images, and forgot to delete those frames, shows in the crop as a streak.)
10%20sec%20RAW%20-%20Version%202.jpg
 

jr24

macrumors regular
Apr 6, 2010
101
0
usa
this is such a fascinating thread! i love it! i really want to learn/experiment with the whole star trail picture-taking deal. it's always been mesmerizing to me. definitely going to bookmark the thread to follow along and to look at all the links.
 

mtbdudex

macrumors 68030
Original poster
Aug 28, 2007
2,670
4,116
SE Michigan
M31/Andromeda take 2

Tues 10/5 I used T1i/Canon 50mm 1.4 prime.

My method: Manual focus on Jupiter (got as small/defined circle as possible), found M31, used ISO800, 4 sec exp, f1/4 (wide open!).
133 light frames, 31 dark frames, 20 bias frames:

1 light frame with exif data for reference straight from camera:
_MG_4351.jpg


A few hour later, DSS churned its magic:
(again 133 light frames, just under 9 minutes total exposure time)
M31%2010-5-10%20v2.jpg


Crop of M31:
M31%2010-5-10%20v2%20-%20Version%202.jpg


This is straight outta DSS - I applied 15% color saturation there to bring some color back, imported into Apple Aperture 3, no PP except slight edge sharpen.
 

mtbdudex

macrumors 68030
Original poster
Aug 28, 2007
2,670
4,116
SE Michigan
MilkyWay: single 30 sec then CS5 vs DSS

Finally got around to processing shots I took 8-10-2010 of Milky Way while in Hillman, MI, about 1 hour away from Mackinaw bridge, very dark skies.
Below is comparison of single 30 sec exposure direct as is then with CS5 PP applied vs DSS 19 minute stacking

Here is single shot of Milkyway directly overhead 11pm-ish, taken with my T1i, Canon 15-85 at 15mm, ISO1600, 30 sec
#1 direct from camera as shot no PP
_MG_1156%20-%20Version%202.jpg


#2 same shot as above, used CS5 for some PP:
(yea, that's a tree on top LH)
_MG_1156%20-%20Version%202%20with%20CS5.jpg


Here is via DSS, 15mm, 57 light images @ ISO800, 20 sec each + 24 dark frames + 30 Bias frames, slight re-frame from above to not get tree in shot:
#3 DSS output (19 minutes total exposure)
MilkyWay_8-10-2010%20v1.jpg


This seems to be my best direct overhead MilkyWay via DSS to date...no matter what I do that lone star gets blow bright/fuzzy in PP ( I could do some local burn to darken it I suppose)

#4 crop version just to remove some DSS edge artifacts and overexposed lone star:
MilkyWay_8-10-2010%20v1.jpg
 

Shacklebolt

macrumors 6502a
Sep 2, 2004
596
0
Tues 10/5 I used T1i/Canon 50mm 1.4 prime.

My method: Manual focus on Jupiter (got as small/defined circle as possible), found M31, used ISO800, 4 sec exp, f1/4 (wide open!).
133 light frames, 31 dark frames, 20 bias frames:

1 light frame with exif data for reference straight from camera:
_MG_4351.jpg


A few hour later, DSS churned its magic:
(again 133 light frames, just under 9 minutes total exposure time)
M31%2010-5-10%20v2.jpg


Crop of M31:
M31%2010-5-10%20v2%20-%20Version%202.jpg


This is straight outta DSS - I applied 15% color saturation there to bring some color back, imported into Apple Aperture 3, no PP except slight edge sharpen.

Great shots everyone, but this in particular is awesome.
 

svndmvn

Guest
Nov 6, 2007
1,301
0
Italy
Finally got around to processing shots I took 8-10-2010 of Milky Way while in Hillman, MI, about 1 hour away from Mackinaw bridge, very dark skies.
Below is comparison of single 30 sec exposure direct as is then with CS5 PP applied vs DSS 19 minute stacking

Here is single shot of Milkyway directly overhead 11pm-ish, taken with my T1i, Canon 15-85 at 15mm, ISO1600, 30 sec
#1 direct from camera as shot no PP

#2 same shot as above, used CS5 for some PP:
(yea, that's a tree on top LH)Here is via DSS, 15mm, 57 light images @ ISO800, 20 sec each + 24 dark frames + 30 Bias frames, slight re-frame from above to not get tree in shot:
#3 DSS output (19 minutes total exposure)

This seems to be my best direct overhead MilkyWay via DSS to date...no matter what I do that lone star gets blow bright/fuzzy in PP ( I could do some local burn to darken it I suppose)

#4 crop version just to remove some DSS edge artifacts and overexposed lone star:

Awesome shots as always!
What kind of PP did you do in CS5 for the single exposure?
About the DSS, do you need to move your camera between shots to follow the stars?
Would that stacking be possible in photoshop as well? Is there any Mac software that gets you that kind of results?
Thanks
 

mtbdudex

macrumors 68030
Original poster
Aug 28, 2007
2,670
4,116
SE Michigan
What kind of PP did you do in CS5 for the single exposure? Histrogram stretch
http://astrochat.co.uk/forum/viewtopic.php?t=13241
and
this whole paragraph from another forum
Here are some screen shots of the curves and levels I'm talking about.
First, here is the type of curve that will bring up shadows yet preserve your stars...

http://www.allaboutastro.com/article...-log-curve.jpg


Yes, it brightens the background, but that will be reset by the following levels adjustment...

http://www.allaboutastro.com/article...vels-reset.jpg


Notice the red arrow. I just dragged the slider a little closer to the hill. Go too close to the hill and you'll overly darken the background.
At the end of the process, you might end up with something like this...

http://www.allaboutastro.com/article...djustments.jpg


Notice two things. One, there's a lot of information in the background that would have disappeared if you left your background black. Two, notice the histogram, how it now gently slopes on the left, yet the hill doesn't extend much further on the right than it did. Because I adjusted curves, the histogram is redistributed, meaning that the shadows now have more of the values than before. Essentially, I've just awoken half of the image that wasn't there in the first place.


In that last one, I did some other tricks to increase contrast in the details, but that's something you'll have to learn later. As a result, the final image is something that I could live with...I'd likely darken the darkest parts a bit more, but that's being picky.

About the DSS, do you need to move your camera between shots to follow the stars? No, that is what DSS does, it aligns your shots for the earth rotation
Would that stacking be possible in photoshop as well? Yes, but for 100's of images not pratical, plus the earth rotation get tricky to align on
Is there any Mac software that gets you that kind of results? That would be sweet, but I'm not aware of any and others have searched as well. Seems astrophotography is so niche that only WinTel stuff is out there. I use VMWare Fusion and WinXP just for this........http://www.vmware.com/products/fusion/
 
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