The method of calculating the optimum point

Optimum focus point (Hyperfocal Distance) for different digital cameras because it has the size sensors and different resolution, this will affect the definition, so you need to calculate and set up a table separate focus points Phone and your lens focal.


Depth of Field to the right of the Calculator, click the show advanced, you will see the following interface software

Step 1: Max Print Dimension (maximum print size)

This parameter shows the size of the photo. Depending on the resolution of your computer, the image can be printed out or displayed on the screen with different maximum sizes. You can use the availability for your machine as follows:

For example, the Sony A7R 36mp fill 25 inches

Step 2: Viewing Distance (Distance view photos)

From your eyes to the screen, or to print à How much?
Example: Viewing images on a 50cm screen, fill 50 cm.

EyeSight (Vision)

To default unchanged

Step 3: Camera Type (type camera)

Choosing the right kind of camera sensors in accordance with the coefficient of your computer. Example:

35mm Full Frame (Canon 1DX, 5D1-3, 6D, Nikon D600-800 / E, Sony A7 / R, A850-900 …)
Digital SLR with CF of 1.6x (The crop plant Canon: 7D, XXD, XXXD ….)
Digital SLR with CF of 1.5x (The crop plant Nikon: D300, D200, DXXXX …)
Digital SLR with CF of 1.3x (Canon 1D, 1D3 …)
For example, Sony A7R, select 35mm Full Frame

Step 4: Selected Aperture (Aperture capture)

Fill out the optimal aperture according to the focal length you use availability above, or the aperture you want to use.
For example, using the Nikon 14-24 lens, 16mm focal length is calculated, Full Frame Sony A7R is, according to the above optimum aperture f5.6. Choose F5.6.

Step 5: Lens Focal Length (Focal lens)

If you sài zoom lens, you see on the tube that shows the focal length, and look HFD for each focal length you need, by entering each focal length for each count.
For example, using the Nikon 14-24 Lens and are calculated for 16 mm focal length.

Focus Distance (Clause way to the focus point)

Temporarily you remain as the default, after you work out is Hyperfocal distance (optimum focus point), then enter your new parameters here to check if it will clarify the picture of what is the most recent and far The last to infinity or not. Speaking exactly is clarity with the nearest acceptable (Acceptable Nearest Sharpness) to have clarity farthest acceptable (Acceptable Sharpness Furthest) is.

Step 6: Click the calculate button to calculate

Step 7: Rounding results

You can see below how much Hyperfocal distance, rounded up to the unit parameters Dm (decimeters = inches) even.
For example, the results of Hyperfocal distance: 1.79 m, rounded 2 m

Step 8: Check Hyperfocal distance

Get rounding parameters, and entered into Focus Distance recently discussed above, click the Calculate button to check it clear to infinity or not, otherwise his rise through the 1 Dm (decimeters = inches).

For example, enter the Focus Distance: 2 m, click the Calculate button, see the following parameters, see the clear picture from almost 0.95 m to infinity, that’s it, recording parameters.

Nearest Acceptable Sharpness (clarity may be the closest acceptable): 0.95 m
Furthest Acceptable Sharpness (High-definition movie can be acceptable farthest): ∞ (infinity)
Total Depth of Field (Total-field): ∞ (infinity)

Tabulate how optimal focus for your computer

You repeat steps 1 through 8 for all combination of focal length and aperture you want to use, set up a table parameters as follows, then save or print your smartphone for easy viewing while shooting.

For example, full frame machines, 36mp, the distance is 50 cm photo viewer.

Focal length f/5.6 f/8.0 f/11
12 mm 1.0 m 0.8 m
14 mm 1.4 m 1.0 m
15 mm 1.6 m 1.2 m
16 mm 1.9 m 1.3 m
17 mm 1.5 m 1.1 m
18 mm 1.7 m 1.2 m
20 mm 2.0 m 1.5 m
21mm 1.6 m
24 mm 2.1 m
28 mm 2.9 m

How to simplify the focus

Along a focus point in an optimal export, you can close a gate smaller (larger f number) or increase the distance of optimum focus point without affecting the sharpness of an image, whereas it also increases the safety of that definition. So I gained focus and flexibility to tune used for export focus point coincides with the focal spot to remember. The following is a simplification for the focus above.

36mp full frame machine, at a distance of 50 cm photo viewer.

Focal length f/5.6 f/8.0 f/11
12 mm 1.2 m
14 mm 1.4 m
15 mm 1.5 mm
16 mm 1.6 m
17 mm 1.7 m
18 mm 1.8 m
19 mm 1.9 m
20 mm 2.0 m
21mm 2.1 m
24 mm 2.4 m
28 mm 2.8 m

Here’s the table of optimum focus shortened

The following is a shortened but his focus was preparation for the common resolution, all based on the distance of 50 cm photo viewer. Because I had to adjust the focus point to coincide with the focal length with decimeters-all to easy to remember, so you just need to remember what the focal length and aperture is being used.

Example: Machine 36 mp full frame 16mm focal length, use the f / 8 and AF in 16 dm / all or 1.6m

FULL FRAME machine

Select the nearest resolution full frame digital camera with your.

The focal The aperture Focus point
12-14 mm f/5.6 1.2 m.. 1.4 m
15-20 mm f/8 1.5 m. 2.0 m
21-28 mm f/11 2.1 m.. 2.8 m

[tab title = “24 mp”]

The focal The aperture Focus point
12-17 mm f/5.6 1.2 m.. 1.7 m
18-24 mm f/8 1.8 m. 2.4 m
28 mm f/11 2.8 m


[tab title = “20 mp”]

The focal The aperture Focus point
12-18 mm f/5.6 1.2 m.. 1.8 m
20-28 mm f/8 2.0 m. .. 2.8 m


[tab title = “16 mp”]

The focal The aperture Focus point
12-21mm f/5.6 1.2 m.. 2.1 m
24-28 mm f/8 2.4 m. 2.8 m



For 1.6 X and 1.5 X CROP machines

Choose the closest resolution camera with your crop. [tabs]
[tab title = “24 mp”]

The focal The aperture Focus point
8-11 mm f/5.6 0.8 m.. 1.1 m
12-15 mm f/8 1.2 m.. 1.5 m
16-20 mm f/11 1.6 m.. 2.0 m

[tab title = “20 mp”]

The focal The aperture Focus point
8-12 mm f/5.6 0.8 m.. 1.2 m
13-17 mm f/8 1.3 m. 1.7 m
18-20 mm f/11 1.8 m. 2.0 m


[tab title = “16 mp”]

The focal The aperture Focus point
8-13 mm f/5.6 0.8 m.. 1.3 m
14-18 mm f/8 1.4 m. 1.8 m
20 mm f/11 2.0 m

How to apply the optimal focus point beyond reality

When shooting you see his focus and aperture is used much then look in your parameters, then the focus at that distance.

Example: Use a 36mp full frame and transcripts of its focus as above, at f / 11 using 24mm is 2.4m, then you find something at that distance around you, not necessarily in the scene you want to capture . Rotate the machine into which objects, focus then turned back and watch plant layout and shooting.

Focus how best to use Live view and enlarge photos up to possible, if your phone has focus peaking function as Sony, use it to help you accurately focus more quickly.

2nd focus is how to use the autofocus function of the machine AF, AF lock is complete, AF Lock button strokes using, or turn off the AF button on the machine and on the lens, this does not exactly using Live view above .

3rd focus is how to focus manually, you have to rotate remotely close and see the lights in the view finder machine definition, the indicator light is displayed definition has recently discontinued.

Do not focus by watching the meter indicated on the lens, so that by 1 mm on both the 10m in the scene depending on the focal length you use, it can cause a very high degree xai blurring the image skewed If you do not make the distance his estimate is correct, should focus more than a few all for safety.

 Combining optimum focus point with the foreground

If the foreground is the focus of the layout, the combined AF optimal parameters you’ve calculated above, plus the right move for the foreground machine at that distance. So we had the optimum focus point, coincides with the focus point of the foreground, like the foreground will be very sharp focus, make eye hook viewers into the depths resulting in very efficient image.

 Check sharpness when shooting

This technique is based on an algorithm applied to the lens of photography, it is theoretical, so you need to check the actual shooting. You should click the Preview button Depth of The Field (see your machine manual), you’ll be in the near and far-field view finder as after shooting practice. Or better still, you take to try, then review and zoom in to inspect 100% focus from foreground to background.

Technical secondary benefit of optimum focus

When taking natural lens you remain so throughout the shoot, because you do not need to refocus for each photo, unless you change the focal length lens or aperture f shooting (or rotate the lens accidentally made a mistake strokes). This is an accompanying benefit, greatly saves time, helps you take advantage of extra time to seize the moment, and what shape your shot well from close to infinity focus. However you need to relocate the machine so that the distance of the optimum focus point coincides with the distance to your foreground.

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