SimCam

ScarySquirrel · 24 May 2007 at 18:59

I am newish to photography and one thing I was struggling to get to grips with was what settings you would use to obtain various levels of DOF. I found this though off another forum which has helped me understand it HUGELY so I thought I would post here as it might help others.

http://www.photonhead.com/simcam/shutteraperture.php

While I am here, can someone explain this please:

Shallow(or is it narrow?) Depth of Field = Foreground in focus, backgroud blurred or vice versa?

Deep(or wide? What is it referred to as?) depth of field = The opposite

divine` · 24 May 2007 at 19:16

ScarySquirrel said:
While I am here, can someone explain this please:

Shallow(or is it narrow?) Depth of Field = Foreground in focus, backgroud blurred or vice versa?

Deep(or wide? What is it referred to as?) depth of field = The opposite

Basically, the depth of field is the area around the point of focus that is still in focus.

So if you focussed on something 5m away and had a depth of field of 1m, then everything from 4.5m to 5.5m would be in focus, everything else getting progressively more out of focus the further from the focal point.

Deeper/Wider DoF will ensure more things are in focus, while a shallow/narrow DoF is good for drawing attention to a certain point in a photo.

ScarySquirrel · 24 May 2007 at 19:19

divine_madness said:
Basically, the depth of field is the area around the point of focus that is still in focus.

That part litterally made me say "OHHHHHHHHH" out loud.

That is all I needed to know and makes everything I have read in the past few weeks make complete sense. Thank you so much

^187 · 24 May 2007 at 19:29

ScarySquirrel said:
http://www.photonhead.com/simcam/shutteraperture.php

Lovely, Ive been having a play today on the very same subject, and dug myself into a little hole of confusion. That has helped me quite a bit, and I have seen the light (pun intended :>)

Thanks for that, gonna read through the rest of the site.

C.

ScarySquirrel · 24 May 2007 at 19:34

^187 said:
Thanks for that, gonna read through the rest of the site.

C.

Glad you said that, didn't even see the other guides, having a read through them now

Nicos Rex · 24 May 2007 at 20:14

To be a total pedant, depth of field is not symmetrical, it is divided 1/3 and 2/3 in front of and behind the nominal point of focus.

Thus to correct the above example, point of focus at 5m and dof of 1 m, the area from about 4.67 to 5.67 m would be in focus

divine` · 24 May 2007 at 20:47

ScarySquirrel said:
That part litterally made me say "OHHHHHHHHH" out loud.

That is all I needed to know and makes everything I have read in the past few weeks make complete sense. Thank you so much

Hehehe, I often find the simplest bits of information can suddenly throw a whole new light onto many more complex theories.

Nicos Rex said:
To be a total pedant, depth of field is not symmetrical, it is divided 1/3 and 2/3 in front of and behind the nominal point of focus.

Thus to correct the above example, point of focus at 5m and dof of 1 m, the area from about 4.67 to 5.67 m would be in focus

You are correct in that it is not symmetrical, however you are wrong in saying that it is split 1/3 and 2/3, the ratio changes dependent on focal length of the lens, focal distance and aperture (to name the main three).

However, seeing as I was giving a very basic outline I figured saying 50/50 would illustrate the point sufficiently without going into detail overload

In the example above, using a 50mm lens on a 400D, at F1.8 the split is 47/53 yet at F8 it would be 35/65.

*waits for someone really clever to come along and tell us all about hyperfocal distance and how that works*

ScarySquirrel · 24 May 2007 at 21:06

That's all too confusing for me, the first sentance to the first reply sorted me out

I have been playing around tonight indoors though and only seem to get shallow DOF on some of my shots.

Messiah Khan · 24 May 2007 at 21:09

ScarySquirrel said:
That's all too confusing for me, the first sentance to the first reply sorted me out

I have been playing around tonight indoors though and only seem to get shallow DOF on some of my shots.

You need a wide aperture(Low F number) to get shallower dof.

Nicos Rex · 24 May 2007 at 21:21

divine_madness said:
Hehehe, I often find the simplest bits of information can suddenly throw a whole new light onto many more complex theories.

You are correct in that it is not symmetrical, however you are wrong in saying that it is split 1/3 and 2/3, the ratio changes dependent on focal length of the lens, focal distance and aperture (to name the main three).

However, seeing as I was giving a very basic outline I figured saying 50/50 would illustrate the point sufficiently without going into detail overload

In the example above, using a 50mm lens on a 400D, at F1.8 the split is 47/53 yet at F8 it would be 35/65.

*waits for someone really clever to come along and tell us all about hyperfocal distance and how that works*

I stand corrected!

Comes from posting in haste information impropoperly remembered from a very long time ago......