Camera won't capture in bulb mode

Jessica Forster

Jessica Forster

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Jessica
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my camera cannon 100D won't take an image in the dark (I.e stars) if i focus the camera on a light subject the lens can see will start bulb mode but pointing it to the stars it won't do anything

What am I doing wrong? I'm in manual mode with f/11 on the basic zoom lens

Thanks in advance
 
How long are you leaving the shutter open?
 
Also, why f11? If this is a thought about setting then fair enough but I just thought I'd ask :D
 
It won't let me start the bulb mode let alone leave it open. So when I press the shutter to active bulb mode nothing happens
 
I've been reading up on Astro photography and the settings and that was a regular f. that came up to be on with a low ISO. Generally asking on here if my settings aren't correct and that's why it won't work
 
Are you changing to manual focus? If you're still trying to auto-focus, the camera would not lock onto anything so won't take the picture.
 
Where are you reading up? As that sounds like some pretty crap advice, I cannot think of a single situation that would warrent shooting at f/11 and low ISO for capturing stars, at those kind of values you'll be looking at 2 minute plus exposures

It sounds to me like your not locking your shutter open, if all your doing is pressing the shutter and then releasing it all your getting is a fraction of a second exposure, what you need is a cheap cable release for your camera that you can lock in the depressed position, this will then hold your shutter open until released to enable you to take multi second exposures in bulb

You want to be looking at a large aperture I'm guessing on your kit lens that will be either f/3.5 or f/4 depending on lens and the as high of an ISO as your comfortable using but on that camera likely about 800 will be as high as you'll want to go before it starts to get noisy

Check my signature an you'll find my guide to star trails this will help you with the basic fundamentals
 
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stevelmx5 said:
Are you changing to manual focus? If you're still trying to auto-focus, the camera would not lock onto anything so won't take the picture.
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Agree - I think your issue is focus. Switch the lens to MF - then you'll see that B will activate. The next challenge is that you have to learn how to manually focus, as it's not simply just turning the focus ring as far as it goes. Check this is the case first - then we can offer further advice once we know.
 
Some cameras won't release the shutter unless they either detect that something's in focus or they're set to fire regardless - have a look in the manual and/or menu to see if that's a reason for it not firing. To get focus set to close enough correct for stars, use the Moon as a target to either MF on of let the camera AF then tape the focus ring down after switching to MF. As Chris says, setting the camera to infinity (and beyond...) using the focus scale on the lens is unlikely to be accurate, hence the suggestion to use the Moon as a target.
 
Almost certainly it's because your camera is trying to autofocus and can't, so it locks the shutter. Mine does that (Canon 550D). The settings you want are - lens as wide open as it will go, 800 iso (higher than 800 and you're liable to get unacceptable long exposure noise, although some cameras handle it better than others), exposure length will then be for you to experiment with and will depend on iso and aperture. With a 18-135mm lens wide open at 800 iso I'll start seeing stars at around 10 secs. If the Moon is visible you can use it to autofocus, then switch the lens to manual without moving anything. If the Moon's not around you can sometimes use the most distant bright object you can see but unless you're on a hill this doesn't really work. The other alternative is to focus on a distant object in daylight, switch to manual focus and tape the focus ring so you can't accidentally move it. With a really long lens there are other methods but I'm guessing you're not using a really long lens. Lenses generally focus 'past' infinity - I think a/f lenses do it so they can actually find infinity focus. You will need the camera well locked down on a good tripod and use a cable or remote release.
 
She does mention using the shutter button.
As above^^^^no! Not for bulb. Get a lockable release. Cost only a few pounds.
And yes, manual focus.
 
T
mickledore said:
She does mention using the shutter button.
As above^^^^no! Not for bulb. Get a lockable release. Cost only a few pounds.
And yes, manual focus.
Click to expand...
thank you, I do know this however having I was only having a practice and getting the hang of bulb mode as it was a random trip to the beach at night and only took my camera out for the day
 
Jannyfox said:
Almost certainly it's because your camera is trying to autofocus and can't, so it locks the shutter. Mine does that (Canon 550D). The settings you want are - lens as wide open as it will go, 800 iso (higher than 800 and you're liable to get unacceptable long exposure noise, although some cameras handle it better than others), exposure length will then be for you to experiment with and will depend on iso and aperture. With a 18-135mm lens wide open at 800 iso I'll start seeing stars at around 10 secs. If the Moon is visible you can use it to autofocus, then switch the lens to manual without moving anything. If the Moon's not around you can sometimes use the most distant bright object you can see but unless you're on a hill this doesn't really work. The other alternative is to focus on a distant object in daylight, switch to manual focus and tape the focus ring so you can't accidentally move it. With a really long lens there are other methods but I'm guessing you're not using a really long lens. Lenses generally focus 'past' infinity - I think a/f lenses do it so they can actually find infinity focus. You will need the camera well locked down on a good tripod and use a cable or remote release.
Click to expand...

So helpful! Thank you
 
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