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500mL
07-23-2008, 11:31 AM
Hey guys,

Just curious, I've been trying to do long exposure shots over the weekend but I couldn't figure out how to. How do I get it to go beyond 30secs? I did bulb but all I get is a black image. And what is mirror lock up? I see it as a feature but have no clue what it's for. Sorry for my ignorance about this, but I just started exploring more features I've never used on my D40/D80.
Thanks all!

-500mL

THANG0359
07-23-2008, 12:06 PM
500ml,

Just turn your dial to the manual mode and turn the shutter speed to bulb, that will allow you to leave the shutter open for as long as you would like, but that would mean that you would have to leave your finger on the shutter button for the amount of time you want it open. The other option is the ML-L3 remote that i use, press it once to open the shutter and again to release, which i think is much better. As for mirror lock up option, that is used when your sensor is dirty, you would use mirror lock up to allow you to actually see the camera's sensor which is reflective green piece and allow you to clean it by removing the dust, of course this is done without your lense mounted on your camera. Don't use it unless your sensor is dirty, you will know that when you see black dots on your pictures. hope that helps..

La

500mL
07-23-2008, 12:56 PM
500ml,

Just turn your dial to the manual mode and turn the shutter speed to bulb, that will allow you to leave the shutter open for as long as you would like, but that would mean that you would have to leave your finger on the shutter button for the amount of time you want it open. The other option is the ML-L3 remote that i use, press it once to open the shutter and again to release, which i think is much better. As for mirror lock up option, that is used when your sensor is dirty, you would use mirror lock up to allow you to actually see the camera's sensor which is reflective green piece and allow you to clean it by removing the dust, of course this is done without your lense mounted on your camera. Don't use it unless your sensor is dirty, you will know that when you see black dots on your pictures. hope that helps..

La

Thanks for your explanation.
That explains why I only see a black screen when I did bulb. I pressed it once but didn't hear the shutter close. I'll give it another shot next time.

As far as the mirror lock up feature, I knew it was for cleaning the sensor if black spots appear on your images. But is there another use for it while taking a picture, or not really?

DonSchap
07-23-2008, 01:31 PM
Mirror lock up is used when you have manually focused on your subject and you have all the settings ready for exposure, where you no longer need to look through the viewfinder for adjustment. It also assumes you will be using either a wired-shutter release or a wireless one. To minimize any kind of camera shake due to the camera's normal operation, locking the mirror up allows the camera to simply open the shutter in front the sensor, then close it again. No other movement should occur.

Long duration and nighttime exposures ... benefit mostly from this kind of preset imagery. You need your "ducks in a row" to preset the camera in such a way.

I hope this helps in your understanding of this feature.

toriaj
07-23-2008, 01:45 PM
Sounds like Don knows what he's talking about, but FWIW I've taken shots up to 30 minutes long and I've never used mirror lockup for that function.

If you don't have a remote, you can use Bulb by using a rubber band to hold down the shutter button. It's not convenient, and it's hard to do without shaking the camera (you do need to use a tripod) but it does work.

Prospero
08-02-2008, 03:52 PM
Mirror lock-up is not really usefull for very long exposures, but for exposures in the range between 1/30s and a couple of seconds.
In that range, the vibrations caused by the mirror slap last for a time span that is significant when compared to the length of the exposure.

With very long exposures (longer than 10 seconds) the vibrations caused by the mirror slap will be neglicable, because they happen in a very short time in which hardly any light is captured.
For the same reason, when doing bulb exposures lasting minutes, you can savely keep the shutter pressed down with elastic band like Tori said. Applying this will cause some camera shake in the first second, but with an exposure lasting minutes, you will never see the effect in the result. Still, a remote is much easier :)

erichlund
08-06-2008, 01:37 PM
If I recall my consumer cam specs correctly (and I do), the D40/D80 only use mirror lock up for sensor cleaning. They do not have a shooting mode. The one and three digit cameras do have a shooting version of mirror lockup, selectable on the mode dial.

Prospero
08-06-2008, 06:47 PM
The D40 and D50 indeed do not have mirror lock-up, but they can open the mirror for sensor cleaning.
The D80 does have a shutter delay function (custom function 31 I read somewhere). It will make sure the picture is taken 0.4 seconds after the mirror slaps up. This will help to reduce the impact of vibrations, but it may not always be enough.