Landscape as a background OOF?

[Stagecoach]

Since undertaking another scouting trip to plan shooting locations for a forthcoming race I have been pondering over whether to aim for sharper or softer backgrounds when I have the option. Apart from what I consider 'race portraits' shot with a longer FL I intend also shooting with a wider FL to emphasise the subject within the highland location and scenery.

Below is a typical image background focussed on what would be a 3/4 to full height subject in it shot at 36mm, f/4 (widest aperture). At the focal length used here f/8 gives me a sharp horizon from the test shots I took.

Imagining a sharp subject included, and taking account of the 'purpose' do you consider a greater DOF is preferable?



Grahame

[Manfred M]

If the images are about the racers, I would do everything to ensure that they stand out against the background. What does the background do if you shoot wide open and focus at a distance where the racer would be running.

[Stagecoach]

If the images are about the racers, I would do everything to ensure that they stand out against the background.

Generally I blur the backgrounds to achieve exactly that, other than in the case where I want a greater DOF for a deep group or the background provides additional interest.

What does the background do if you shoot wide open and focus at a distance where the racer would be running.

The above example is focussed on the plane the runner would be on in the road and shot wide open. It's the minimum DOF/max background blur I could achieve with the f/4.

[xpatUSA]

Grahame,

To get a 6ft tall runner to be about, say, 18mm (just over two-thirds picture height) in the image plane, the magnification has to be 1:100.

Therefore, a practical shooting distance for 36mm focal length would be dictated by that magnification -between three and four meters -about 3.6m. For the aforesaid 36mm focal length set at f/4 at 3.6m distance, -my DOF calculator gives the far focus as about 5.2m and the near focus as about 2.7m. So, a hyperfocal distance of about 11.5m and DOF of about 2.5m.

With the above settings and shooting distance, my blur calculator says that a point source at 10m distance would have a blur circle about 10 pixels diameter, guessing your sensor at 6um pixel pitch.

Based on all of that, your wide-open f/4 doesn't look too bad ...

... and I don't think that more DOF e.g. from f/8 would be preferable.

[Wavelength]

Scrolled down, until an exact triangle of the foreground road remained within the frame along with the background greenery; i felt that is a very fine scenery; so you may please keep such a crop to your collection.

[Manfred M]

Generally I blur the backgrounds to achieve exactly that, other than in the case where I want a greater DOF for a deep group or the background provides additional interest.



The above example is focussed on the plane the runner would be on in the road and shot wide open. It's the minimum DOF/max background blur I could achieve with the f/4.

I personally would prefer the background to be a bit softer; you are at the point where you've just taken the edge off the sharpness, but not enough to reduce the distraction. Tough call here. I look forward to seeing the finished images.

[Stagecoach]

Grahame,

To get a 6ft tall runner to be about, say, 18mm (just over two-thirds picture height) in the image plane, the magnification has to be 1:100.

Therefore, a practical shooting distance for 36mm focal length would be dictated by that magnification -between three and four meters -about 3.6m. For the aforesaid 36mm focal length set at f/4 at 3.6m distance, -my DOF calculator gives the far focus as about 5.2m and the near focus as about 2.7m. So, a hyperfocal distance of about 11.5m and DOF of about 2.5m.

With the above settings and shooting distance, my blur calculator says that a point source at 10m distance would have a blur circle about 10 pixels diameter, guessing your sensor at 6um pixel pitch.

I had not delved into the calculations Ted, it was far more fun spending 6 hours driving up and down many steep tracks and taking pics to see the results. But, the fun was short lived when I got home with the "what if something had happened to you alone up there in the dark" and then the "you better get that car cleaned, again"

Based on all of that, your wide-open f/4 doesn't look too bad ...

... and I don't think that more DOF e.g. from f/8 would be preferable.

That's one for 'not more DOF'.

[Stagecoach]

Scrolled down, until an exact triangle of the foreground road remained within the frame along with the background greenery; i felt that is a very fine scenery; so you may please keep such a crop to your collection.

Thanks Nandakumar. Framing is not my concern, it is whether sharp or softer backgrounds are preferable when trying to emphasise both subject and environment.

[Stagecoach]

I personally would prefer the background to be a bit softer; you are at the point where you've just taken the edge off the sharpness, but not enough to reduce the distraction. Tough call here.

This week I'll be taking another scout along the full route at the same time as the actual run to assess the lighting so I'll take the 28-75 f2.8 along on the D300 and do similar background OOF tests.

[xpatUSA]

If you had any latitude as to focusing distance that might be something to try out if you get bored.

This might be of interest, Grahame:

https://lewiscollard.com/technical/background-blur/
.

[William W]

Since undertaking another scouting trip to plan shooting locations for a forthcoming race I have been pondering over whether to aim for sharper or softer backgrounds when I have the option. Apart from what I consider 'race portraits' shot with a longer FL I intend also shooting with a wider FL to emphasise the subject within the highland location and scenery.

I suggest that you aim for a softer background, when you have the option.

More importantly, I think that, when using a W/A lens to 'emphasise the subject within the highland location and scenery' , then the placement of the main Subject relative to the Background's Texture and Colour is more important and generally will have a stronger effect for the purpose of separation.

For example, in your test shot, I would shot the Key Runner in front of the large mountain on the left or the dense shrubs on the right and re-frame the shot to accommodate that placement.

Whilst Shallow DoF is a good tool for separation, there are other tools you can use too: in this situation placing the Subject on the appropriate Background will be easier and more effective.

WW

[Stagecoach]

I suggest that you aim for a softer background, when you have the option.

Ok, that's another for softer. That puts me in the position of having to review which camera I use for long and short FLs. I'm planning no lens changes due to anticipated rain/damp or sun and dust.

More importantly, I think that, when using a W/A lens to 'emphasise the subject within the highland location and scenery' , then the placement of the main Subject relative to the Background's Texture and Colour is more important and generally will have a stronger effect for the purpose of separation.

For example, in your test shot, I would shot the Key Runner in front of the large mountain on the left or the dense shrubs on the right and re-frame the shot to accommodate that placement.

That's something I had not conciously thought of but certainly will now whilst positioning and preparing, where it's a possibility. What I will be attempting to do where possible is get in the long shots then quickly moving to a pre-planned position for the wide ones. Much will be just of single runners as they will be very separated over the course.

Whilst Shallow DoF is a good tool for separation, there are other tools you can use too: in this situation placing the Subject on the appropriate Background will be easier and more effective.

WW

Agree.

[William W]

you're doing good planning ... break a leg. regards.