Had another bash at startrails

blastman

blastman

blastman

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hey guys,

So after taking your advice, I decided that Sunday was the night that I'll make the magic happen! So, I setup my camera, pointed at the north star, dialled in the following settings and let it go!!

shutter speed: 30sec
F-Stop: 4.5
ISO: 200
Shot type: High burst
Remote shutter release cable used as it has a lock option.

200 images later, this is the result. Needless to say, I'm very happy with it :)

6046813143_36fd4d78c1_b.jpg


C&C welcome :)
 
BBQ chinmey pot is majorly distracting lol

but very nice trails, the sky seems very bright for a night time shot, was it mid to late evening? sky seems a tad too blue compared to most star trails i've seen :)
 
Wow, I'd love to be able to this. I have just started with photography and I am going to try this. I have a Nikon D3100, 18-55mm lens, but no tripod yet. Not sure if I need a remote.
 
Love it...

I disagree with Seraph... I think the BBQ chimney pot is a great part of the shot and I love the colour of it. Very well done :)
 
Thanks chaps.

It took me a while to get the chinenia in the shot and I'm pleased with it.

Once I got all 200 images into lightroom I processed one of them and then sync'ed the rest. Then used startrails to stack them all together.

I've been bitten by the bug now so expect some more!
 
I've just noticed two "notches" in a fair few of the star trails and I can't stop seeing them now :(

Have some pictures gone a miss when stacking ?
 
Dam, you saw them!

Yeah, images 8 and 23 had to be dropped as my.drunk brother in law a, threw a fag in and b, simply got in the way. Douche.
 
blastman said:
Dam, you saw them!

Yeah, images 8 and 23 had to be dropped as my.drunk brother in law a, threw a fag in and b, simply got in the way. Douche.
Click to expand...
PS is your friend:

Enlarge canvas.
Add vertical and horizontal guides to give exact middle point of canvas.
Move image such that the centre of rotation is over the cross-hairs.
Blur > Radial blur (probably lowest setting, but depends on image size).

That method includes any foreground / trees / etc, though so isn't exactly ideal. Best to do it and then use the blur layer to paint over the most obvious gaps with a layer mask, rather than revealing the whole thing. Your other alternative is to jump the sky to a separate layer beforehand, so that it doesn't include anything not-to-be-blurred. That's a better option, but extracting the sky can be a pain in itself.

There are better stand-alone programs that will fill gaps (and extend trajectories :p) if it's something that you're interested in doing more, but you'd have to pay for them.
 
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When you say you've stacked them, do you mean you put them in order and the software squashed them into 1 image ? :confused:

I always thought you just took 1 picture but left the lens open for X amount of minutes so it catches the light.

Looks very good tho.
 
yeah man looks cool

As above though, I thought you set your camera to bulb mode and use a remote lock shutter to get trails like that?

could be wrong as never tried lol

good effect though, I like the chiminea too
 
BTW You can buy an Intervalometer that works with most cameras for about ~15 quids. I use one with my EOS and it works as good as the "branded" one...
You specify the interval, the exposure time, the number of shots, set the camera in bulb mode and boom you can go away and let it shoot...

For your missing images, you could take image-1 and duplicate it, rotate it slightly using polaris as center, add a mask for just the sky and merge it back...

Here is a variation on star trails, this one is 20 minutes at low ISO (200). I light painted the tower with a blueish LED torch to make it pop out.

IMG_7751-Edit.jpg
 
All you need now is a mount that can track and it opens up widefield astrophotography..

If you want a camera only tracker - astrotrack is a good option - it's portable and light although expensive. Otherwise you're looking at telescope equatorial mounts which are bigger, heavier and expensive - for example skywatcher are a good brand.
 
Cyclone said:
When you say you've stacked them, do you mean you put them in order and the software squashed them into 1 image ? :confused:

I always thought you just took 1 picture but left the lens open for X amount of minutes so it catches the light.

Looks very good tho.
Click to expand...

You can't really do this due to noise. If you left the shutter open for 30-60mins you would have terrible noise even at ISO100.

Doing it in short bursts and stacking them results in a much cleaner image.
 
You can do it and the noise isn't the problem its the hot pixels.. Problem is to allow your camera to find them and remove them means doubling your exposure time so 4 hours becomes 8 hours.

Stacking is a much better solution because yes the images are cleaner and it allows you to customise the length of your exposure by choosing not to include the start or the end of the shoot due to clouds etc etc. Very easily open each file into one document in photoshop and change each layer apart from the base layer to overlay in the layers options.. Boom, stacked.. Or theres plenty of automatic mini applications out there to do this.
 
i used startrails.exe which is free and creates the stacked image as well as a time-lapse which is very cool.
 
hot pixels ppffftt.. not a problem - use a pixel defect map and apply it to each picture before stacking. The app will use the pixels around it to resolve the values.

What you do is take a set of images with the lens cap on. These are called "darks". Same duration as your star images so the voice signature is the same as your normal exposures. The hot pixels then appear (although stacking darks to become a dark master is better). Then use that dark master as the defect map.

Additionally due to DSLR amp noise, it's usually a good idea to allow a gap between each exposure to allow the camera to cool down. Alternatively you can put the camera in a peltier cooler 'fridge' that surrounds the camera.

The idea is to create a large "signal" by stacking images. The same elements (stars, moon, houses etc) in a picture then build up signal strength whereas the noise, because it differs between frames, then doesn't build as quickly. However for star trails the subject is always moving (so the signal doesn't stack as much) so the noise reduction isn't as good. So you'll probably find it better to use darks stacked.

You can use 'lights' for dust/aberration removal.
 
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BTW you can buy motorized mounts (equatorial, not Alt-Az) for /really/ cheap, I bought one last year with a rather not bad Newtonian 8" that is also not completely useless, the lot (with one motor) for barely over 100 quid...
Allright it's all chinese, but with a few hours of cleanup and adjustments, it works fairly well, especially for mounting a DSLR...
 
You can make a tracking mount too - called barn door trackers. They're basically a wedge with a hinge and a motor to move at the right rate. :)
 
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