Beginner Shallow dof and long shutter speed

[YellowPages]

Good evening,

If I use a wide aperture (1.8 or 2) and a long shutter speed, does it make more of the scene in focus and a deeper dof?

I know large aperture causes shallow dof but it's usually accompanied by a fast shutter speed. But if there is little light and I accompany it it with a long speed, does it make any difference? Or it changes nothing?

Thank you,

 

[woof woof]

The amount of time doesn't alter the depth of field. Aperture and camera to subject distance do (and arguably focal length too) but shutter speed doesn't.

Leaving the shutter open longer will/could change the exposure so assuming your aperture remains unchanged and the shutter speed changes (gets longer) you'll have to reduce your ISO setting and once you can't reduce it any more the shot will over expose... unless you put a ND filter on the lens... but all this is pointless as your dof will remain the same

 

[Dennyboy]

Depth of field won't change. 1.8 or f2 is the same whatever the shutter speed. Opening the aperture allows more light equalling more speed. To get a long exposure with a large aperture sometimes you have to reduce iso or even add a filter to stop the light entering. Low light as described equals a longer shutter speed required to allow the same light to achieve the correct exposure. http://www.techradar.com/how-to/pho...rture-shutter-speed-and-iso-explained-1320830

http://digital-photography-school.com/understanding-depth-field-beginners/

 

[YellowPages]

The amount of time doesn't alter the depth of field. Aperture and camera to subject distance do (and arguably focal length too) but shutter speed doesn't.

Leaving the shutter open longer will/could change the exposure so assuming your aperture remains unchanged and the shutter speed changes (gets longer) you'll have to reduce your ISO setting and once you can't reduce it any more the shot will over expose... unless you put a ND filter on the lens... but all this is pointless as your dof will remain the same

Depth of field won't change. 1.8 or f2 is the same whatever the shutter speed. Opening the aperture allows more light equalling more speed. To get a long exposure with a large aperture sometimes you have to reduce iso or even add a filter to stop the light entering. Low light as described equals a longer shutter speed required to allow the same light to achieve the correct exposure. http://www.techradar.com/how-to/pho...rture-shutter-speed-and-iso-explained-1320830

http://digital-photography-school.com/understanding-depth-field-beginners/

Thank you. For some reason it was puzzling me. But it makes sense that less light needs longer to create the same effect as more light for less time.

 

[juggler]

Good evening,

If I use a wide aperture (1.8 or 2) and a long shutter speed, does it make more of the scene in focus and a deeper dof?

I know large aperture causes shallow dof but it's usually accompanied by a fast shutter speed. But if there is little light and I accompany it it with a long speed, does it make any difference? Or it changes nothing?

Thank you,

Crudely..

A wide aperture will make anything you haven't focused on blurry
A long shutter speed will make anything moving blurry.

A wide aperture will make the image brighter.
A long shutter speed will make the image brighter
Increasing ISO will make the image brighter.

 

[mike weeks]

Crudely..

More precisely

A wide aperture will make anything you haven't focused on blurry

focal length also has an impact

A long shutter speed will make anything moving blurry.

How long is long?, better is lengthening the time the shutter is open will not freeze movement as much, shortening in will freeze more

A wide aperture will make the image brighter.

A wider aperture will make the image brighter without adjusting the other 2 members of the exposure triangle i.e. ISO and shutter speed

A long shutter speed will make the image brighter

Lengthening the shutter shutter open duration

Increasing ISO will make the image brighter.

 

[juggler]

More precisely focal length also has an impactHow long is long?, better is lengthening the time the shutter is open will not freeze movement as much, shortening in will freeze moreA wider aperture will make the image brighter without adjusting the other 2 members of the exposure triangle i.e. ISO and shutter speedLengthening the shutter shutter open duration

Of course there are a huge number of factors in play. I was trying to present things in the simplest possible terms, and to emphasise that there are two main causes of blurriness; something that the OP didn't originally seem to have got their around.