Star Trails - Any tips?

bwana

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Oh wow ... Not sure what I was saying ;)

Apart from noise being an issue, the 28mm isn't sharp - so trees or anything in the foreground isn't sharp :/

EDIT : Rather, not as sharp as I hoped when focusing far
I don't think noise is a by-product of the lens. Also check the aperture you're shooting at. Few lenses are at their sharpest wide open. You may find stopping it down goes a long way.

You also need to decide if you want to be a photographer or a pixel peeper. ;)

EDIT: Remember also that if you're shooting in RAW you have to do sharpening since the camera isn't doing it for you.

EDIT2: you mentioned elsewhere you were relying on manual focusing. Make sure your diopter is correctly set. I put a drop of the missus' white nail polish on mine so I can quickly see if it has been nudged out of place.
 
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Dolby

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It's a Canon 28mm F2.8.

I find it clear within a few meters - but thereafter it becomes soft. I'll try stopping it down - but when I take star trails I try on F11 or so. It's still not sharp enough ... and it's not pixel peeping ;) I'll show you an example tonight.

So far I've only shot JPEG ... but now I'm tempted to try RAW.

Regarding the other EDIT, I'm going to have to Google because I have no idea what you're talking about ;) Is it the viewfinder thumb dial thing? I use the screen to manual focus ... on a tripid ... and zoomed at 10x to fine tune.
 

Quantum Theory

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If your depth of field is too shallow and you focus to infinity, the foreground will be out of focus.
 

Dolby

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If your depth of field is too shallow and you focus to infinity, the foreground will be out of focus.

I generally use F11 or higher for star trails - and the house I want in clear focus is about 30m away. My mother wouldn't notice it as being out of focus - but I reckon most of you would and, importantly, I do ;)
 

bwana

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I generally use F11 or higher for star trails - and the house I want in clear focus is about 30m away. My mother wouldn't notice it as being out of focus - but I reckon most of you would and, importantly, I do ;)
And you're focusing on the house or the stars?
 

Dolby

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The house

bwana - you have any examples of star trails?
 

bwana

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The house

bwana - you have any examples of star trails?
I suppose if you're having problems getting a house in focus then there is a problem somewhere.

I was just thinking earlier it might be fun experimenting with star trails but my sissy-sticks aren't particularly sturdy* so trying to find a night still enough could be problematic.

* new question - how sturdy are yours?
 

Dolby

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* new question - how sturdy are yours?

Average, I guess ;)

It is about 20 years old ... so I guess I need a new one. But at 28mm over such a long period, a tiny shake should be almost negligable though?
 

koffiejunkie

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Speaking of tripods, for star trails, as long as you don't change the tripod's position, slight vibrations doesn't really make a difference.
 

koffiejunkie

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That looks sharp enough, at least at 1024x768. But seriously, you shouldn't check out http://www.dofmaster.com/dofjs.html, calculate the hyperfocal distance, and set the lens to that, or slightly further out. Your shot will be in focus.

And you really need to find a place with less light pollution :)
 

Dolby

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I'm going to Clarens in a week and a hhalf - 3 days after new moon ;)

This was just an attempt - but I thought the foreground (house, tree) aren't sharp enough. It felt like the ring should have got .5cm further to ssharpen.

PS Resized because even though it daid 100% uploaded, it wasn't working :/

Maybe I'm being too analk
 

creeper

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Also remember that a small f stop can lead to softness. My general setting for star trails are

F8
Iso100
Mirror lock up. + tripod + remote release. Remember to let the mirror come to rest and then open the shutter
30min
Full battery
Extra battery (if it is cold, place in underwear as it will ensure that the battery works to it's full potential)
 

B.K

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Here is one I did the other night

65 30s exposures (stacked)

Nikon D3100, 35mm f11 ISO400 (Thought I had set that to ISO100 :( )

Startrails-35mm-01.jpg
 

Dolby

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So max is not the sharpest - generally 2 or 3 stops more ... But then it declines?
 
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