Tag Archives: Depth of Field

Maybe we need to RETHINK how we think about Depth of Field

Maybe we need to RETHINK how we think about Depth of Field

It’s really about Magnification

We know some truths about Depth of Field (DOF). We know there are 3 things (actually 4 but the forth is controversial and not all agree and it would only apply if you switch cameras in between shots)

Anyway, there are 3 things that affect Depth of Field

  • Aperture
  • Distance to Subject
  • Focal Length

We know:

  • The Larger the aperture (lower f/ number),the shallower the Depth of Field
  • The closer we are to our subject, the shallower the Depth of Field
  • The longer the Focal Length, the shallower the Depth of Field

and of course the inverse of all would be true Continue reading »

Depth of Field – In Depth

Depth of Field – In Depth

Everything you wanted to know about Depth of Field and some things you didn’t but you will be glad you did

So you may think you understand Depth of Field (DOF) but do you? Let’s try to confirm what you do know and maybe show you a couple things you didn’t.

What is Depth of Field?

Let’s start with a definition: Depth of field is the total distance that is in “acceptable focus” from our actual point of focus. Let’s clarify that definition further because we artistic minded hate reading definitions.

When you focus on an object, you have a “point of focus” that is the only part that is 100% sharp and in focus, then you have a “field of acceptable focus” in front of and behind that point. That area is the total Depth of Field Continue reading »

Help! I’ve broken my Bokeh and I can’t get up!

Bokeh is a term used for the Quality of the  OOFF (Out Of Focus Field) in an image. NO IT IS NOT the term for an image with a shallow depth of field. That would be: An image with a shallow depth of field. LOL

But a great bokah in an image is a very desirable things. Most times when we shoot HDRs we really don’t worry about this because we are shooting for a very deep DOF. Bokeh would be irrelevant for most of our shoots.

But suppose we want to be different, we want to use our artistic side and we want to shoot a subject and then have a very shallow DOF. No problem shoot away BUT as nice as HDR will make the subject of your image it will have a totally detrimental effect to the OOFF area and destroy any great bokeh your lens may have.

Let me show you, For this image I used my Canon 70-200L 4.0 lens which is known for it’s excellent bokeh. I shot a day lillie in front of my home with 3 exposures and at 200mm f/7.1. Now you may say f/71. That’s not going to give you a very shallow DOF, actually it’s probably still not enough since my Focal Length was 200mm and my distance to subject was 5 feet, that still gives me just a few inches of DOF. Shooting wide open would have given me less than an inch of DOF.

I processed the images in Photomatix Pro 4.1 and used the Painterly preset, Just taking the strength down a notch and adding a bit to the black levels.

Here is that image

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Now some may say,” That looks great”. And to an untrained eye it may. Because HDR brings out detail and perceived sharpness it is applying that to the background to the same degree that it does out subject where we do want the fine detail visible. The same thing can occur when someone oversharpens a standard photograph and applies that sharpening equally to the background. You are sharpening something that is not meant to be sharp and it destroys the look of the image.

But now look at the OOFF of a standard image with the true Bokeh of that area.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Look at the softness and smooth transition of tone in the background. But we loose the extra tone and detail we may want in the our subject; the flower itself.

So is all lost? Not at all. Through the magic of Photoshop and our friend the layer mask, I took the HDR image and dragged it on top of my standard image and then just masked off the background to reveal the standard image background. Problem solved.

QUICK HINT: If you are dragging an image on top of another image and want to make sure that the two images are aligned. First start by dragging the image with the shift key held down. Then to fine tune the alignment, change the Layer mode on the top layer to “Difference” and the image should turn black, The better you align the images the more black the entire image will look especially on edges. Once you have the images aligned, return to Layer mode to normal.

This is the final image, HDR Subject, standard background with that creamy Bokeh