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lesson no 1 in star trails.........
- Thread starter Lynton
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:rules:
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- Name
- Ken
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do not , i repeat do not take 100 x 25 sec full size 16 mpx, 17mb jpegs and attempt to stack them...
you will melt the CPU.
Pictures of the CPU or it didn't happen
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- Julian
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Took my first star trails last night 103 images at 30 sec exposure each on full frame 21mp. Using starstax it was fine. Suggest your pc was way under powered ?!?!
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- Julian
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And here it is ......
Arghhhh racton
Ruin?
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- Julian
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jimmy83 said:
Yep, Racton Ruin
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Just out of interest - I'm trying to get pin sharp star shots - just managed it a few times.
Obviously the infinity focal point needs to be found on the lens, it's not always right at the end, but do you find 25 sec or 30 sec exposures are too long? I'm sure the stars move slightly giving a blur.
A quick test last night showed I'm having better results with 15 sec.
Obviously the infinity focal point needs to be found on the lens, it's not always right at the end, but do you find 25 sec or 30 sec exposures are too long? I'm sure the stars move slightly giving a blur.
A quick test last night showed I'm having better results with 15 sec.
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- Darren
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The Earth spins fast enough that you'll get motion blur. The shutter speed you can get away with depends on your focal length and camera format, you're supposed to be able to divide a number by your focal length and get roughly the longest shutter speed that you can use without getting blur.
For full frame it's 600/focal length=shutter speed.
For Canon APS-C it's 400/focal length=shutter speed.
E.g. A 50mm lens on a Canon 50D
400/50=8
Which means you can use an eight second shutter speed at that focal length before you get blur. A longer focal length would require a faster shutter speed while a shorter focal length would allow a longer shutter speed.
I've been finding that I have to go a lower than the speed I get from the maths, though it depends on how you're presenting your images. If you're putting 1024px images on the internet you'll get away with more blur than you would with a large print.
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- Chris
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Takes my laptop far longer to export 100 odd Jpegs (1920x1080) than it does to stack them using GIMP. In fact I can stack them, and then make a time-lapse of the trail with Quicktime faster then the lightroom export. And probably then get the kettle on!
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great shot!