Saturday, 14 February 2009

Subject Isolation

Do I need a better portrait lens than my EF 50 F1.4 or EF 100mm F2.8? Bokeh, is it pleasing enough and can I separate the subject enough from the background (subject isolation)? Do penguins' feet freeze? Does anything eat wasps and are polar bears lonely? Will we survive the credit crunch?

These and even more pressing questions keep us awake at night. Don't they?

Well, get the books based on a column in The Scientist and I can help you sleep better by answering the lens questions :-)

First of all, what are we talking about with regards to "Bokeh" and "Subject Isolation"? I don't know, I just sound like I know what I am talking about! :-)

Bokeh - Simply put is a term to describe the out of focus or blurred out background of an image, where the main subject is in sharp focus.

Subject Isolation - Is the result of "good bokeh" from a narrow depth of field.

The "EF 70-200 F2.8L IS" will work very well as a telephoto lens for portraits. I wanted to test these two primes that I own to see if I needed to get the EF 85 F1.8 (can't justify the £1,700 price tag on the EF 85 F1.2L).

You've probably deduced that I'm shooting on a Canon ;-)

So here they are. My conclusion is at the end of these images.

The camera is left at the same place at the end of the hallway. First I put the 50mm on the camera and take a series of shots with the deodorant can, I mean subject, at receding distances. I then put on the 100mm and take the same series of shots.

The 50mm F1.4 lens @F1.4

The 100mm F2.8 Macro lens @ F2.8

The 50mm would be great in a close environment, within 2 metres of the shooter as it would allow more of the subject into the frame. The 100mm would be better suited for medium length, over 2 metres distance.

Bokeh wise they both provide similar results in quality. The further away the subject the greater the DOF and so Subject Isolation, a function of Aperture, Subject Distance and Background Distance to the Subject, reduces.

Are they good enough then? They are but I don't want to be as close to the subject as the 50mm requires. I want the same Bokeh and Subject Isolation as the 50mm gives at close distance (the first image) but with a greater reach without being in the subjects face. The 100mm would not work in a close environment, say a small room but would be great outside.

So something in-between might work? ;-)

No comments:

Post a Comment

My Website: