V.slow shutter speed leading the extremely over exposed shots?

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Dub

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Hi

I've had a read around and I have a vague idea but I'd just like to make sure that what I'm thinking is correct.

I've got a sony A390, set to S and it was on the slowest shutter speed.

What I was taking was a picture of a car and wanted to do was the highlight the amount of people walking around the car.

It was an outdoor picture, the sky was overcast and quite bright and creative style set to portrait.

The outcome was this:
http://i.imgur.com/6aE3i.jpg
:bonk::thumbsdown:

Any help would be appreicated.

So my questions are what did I do wrong and what should I have done?
Also, I'm guessing that no amount of post processing could fix this?

Thanks a lot in advance!
 
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If you have shutter priority and set it too slow for the ambient light level then this can happen. I think the shutter speed flashes in the display if it is way off.

Without exif it is hard to tell. What iso did you have set? What aperture?

In bright light you'd probably need a neutral density filter to lower the light level sufficiently to use the slower shutter speed you were after.
 
You have simply used a shutter speed that is way too long for the bright conditions.

You would need to use ND filters to be able to do what you are after. And even the shutter speed you have picked would still be too fast to get the movement you are after as the people in the background are not that blurred.

You will need to put ISO on lowest, use a large aperture number and an ND filter or a combination of those.
 
Ernesto has got is bang on - ND filters will increase the exposure time once you've selected a narrow aperture (something like f/16) and the lowest ISO possible.

You'll obviously be using a tripod but just be wary of people brushing past that could knock it and change the composition mid-shot.... you'll be able to tell if this has happen, as the stationary part of the shot (the car) will look shaky.

Also, if you have the function, use mirror lock-up; this means when the shutter is pressed the mirror is raised but several milliseconds pass before the shutter moves, meaning that any mirror slap vibrations have passed and won't register as movement on the shot.
 
Thanks for the responses.

I did have the ISO set to lowest and I don't remember the aperture setting but I think i'll need to invest in a ND filter to be doing this again!
 
If you haven't got a ND filter, you can achieve the slowest shutter speed possible for the prevailing conditions by a) setting the ISO to it's lowest value and b) set the aperture to it's smallest opening, i.e. largest number, with the camera in Av mode.

The camera will choose the shutter speed to get a correct exposure, but by following the above steps, it will be as slow as you can get away with. If the shutter speed isn't as long as you require or would prefer, you will then need to start thinking about ND filters.
 
DUB - remember, diffraction happoens at high f-numbers (f/22 etc) and can actually decrease the IQ.... I'm no expert at diffraction but I think on crop bodies f/16 is about as high as you want to go. Bear that in mind when setting your shutter speed at ISO 100 as you may still be left wanting for less light hitting the sensor, which is where a good quality ND filter will help.
 
I remember having the same problem wanting to take long exposure pics of a waterfall, I was gutted as I didnt realise that a ND filter was needed to get the exposure correct, I purchased a cheap one to start off with and was really pleased with the results - I would also definitely recommend :)
 
If you don't have an ND filter, but do have a CPL, you can use the fact that a CPL will drop about 2 stops to get part way there.
 
Most blurred/movement people/crowd shots are done at night. Much easier. And even then you want an ND filter. For broad daylight you'd want something like the big stopper.

http://www.amazon.co.uk/Single-Coat...HP7U/ref=sr_1_2?ie=UTF8&qid=1348491892&sr=8-2

Obviously one with the right filter thread for your lens. Shoot manual, set the exposure, ISO and aperture manually. ISO down to 100, aperture down to f/16 or f/22 - focus the shot before you add the filter and switch the lens to manual focus, without touching the focus ring. It's trial and error after that, to see what exposure length works best.
 
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