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[deeky]

Yeah, I know a longer focal length will shallow the dof,.....

That is a very common misconception.

A longer focal length magnifies everything in a scene, including any blurred background. If you use a longer focal length, move further back to keep subject scale in the image frame the same, and use the same lens aperture, the DoF stays pretty much the same as it was at the shorter focal length. The now magnified background seems to be more blurry, but the blurred parts are now just magnified.

You can verify that by plugging numbers into an online DoF calculator.

Now lets consider what happens when a longer focal length is used.
We'll use a 1.6 crop factor image sensor, a 50 mm lens at f/4 and a 100 mm lens also at f/4.
We will keep our main subject scale in the image frame the same for both lenses, so we will use the 50 mm lens at 10 feet and the 100 mm lens at 20 feet.

For the 50 mm lens set to f/4 and a PoF 10 feet from the image sensor we get (PoF = Point of Focus)
Total DoF - 1.84 feet
DoF starts - 0.84 feet in front of the PoF (45%). (9.14 feet from the image sensor)
DoF ends - 1 foot behind the PoF (55%). (11 feet from the image sensor)

For the 100 mm lens set to f/4 and a PoF of 20 feet we get
Total DoF - 1.83 feet
DoF starts - 0.87 feet in front of the PoF (48%). (9.14 feet from the image sensor)
DoF ends - 0.95 feet behind the PoF (52%). (11 feet from the image sensor)

Note that the 50 mm and 100 mm Dof is very nearly identical, though there is a signficant change in the DoF distribution that makes it closer to 50%/50%.

I used this online DoF calculator - Online Depth of Field Calculator
And recommend this tutorial - Understanding Depth of Field in Photography

Fair enough - it's a perception thing and I understand that, but was speaking for the op who doesn't sound to be too far into this yet. I was trying to keep it simple for them but could have been clearer. Clarity and simplicity - often as reciprocal as shutter speed and aperture.

 

[ryanparker]

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[greybeard]

I really like #2. With PS you could blur the twigs in the background, adjust levels, crop a little from the left to de-center things a bit, and sharpen and brighten the eyes a touch. This photo could have some real IMPACT!