Sony RX100 M4: Hyperfocal Distance

On this page, I present a hyperfocal distance (HFD) table for the Sony RX100 M4 that was calculated using Excel. The calculations are based on formulae that I found on the DOFMaster Website and described on page Calculating Hyperfocal Distance and Depth of Field. Since the Sony RX100 M4 displays the distance in manual focus mode only on a coarse scale, the usefulness of the table is rather limited.

Note that the tables can also be used for a simplified version of the Merklinger method for determining depth of field, where distance is set to infinity. Then, the hyperfocal distance is the "near limit" according to the conventional approach based on the circle of confusion (the Merklinger approach does not provide such a near limit). Since you just read the values from the table and do not set anything, there are no problems involved here.

See the notes on page A Small Glossary of Photography Terms regarding the validity of depth of field and hyperfocal distance calculations as well as of the circle of confusion, on which these calculations are based.

Note: For details, see my general page Calculating Hyperfocal Distance and Depth of Field.

Introduction

The hyperfocal distance is useful for shooting with manual focus and aperture. When you set a lens to the hyperfocal distance, everything will be sharp from half the hyperfocal distance to infinity. Sharpness is defined by the circle of confusion (coc). Sony sets is set to 0.011 mm for the RX100 M4's 1" sensor.

The hyperfocal distance depends on three factors:

Focal length (the exact length, not the equivalent length),
Aperture (f-number),
Circle of confusion (coc).

I present the formulae for calculating the hyperfocal distance on page Calculating Hyperfocal Distance and Depth of Field.

You can calculate the hyperfocal distance for a given focal length and aperture using DOFMaster. Set the circle of confusion to 0.011 mm for all focal lengths.

Examples:

8.8 mm, f/2, 0.011 mm: 3.53 m (1.765 m to infinity); 8.8 mm, f/5.6, 0.011 mm: 1.25 (0.625 m to infinity)
25.7 mm, f/2.8, 0.011 mm: 21.25 m (10.625 m to infinity); 25.7 mm, f/8, 0.011 mm: 7.53 m (3.765 m to infinity)

For the Sony RX100 M4, you can also determine the hyperfocal distance "after the fact" by inspecting an image's Exif data using ExifTool or other tools that use the ExifTool engine. They are listed in the "Composite" section, which are useful parameters that ExifTool calculates from other data. Here, a circle of confusion of 0.011 mm is listed.

Figure 1: Inspecting Exif data in GraphicConverter for the hyperfocal distance and the circle of confusion

Note that the Exif Tool dta differ slightly from my own calculations (for unknown reason). In the following, I present my own calculations of the hyperfocal distance and offer them in tabular and graphical format.

Table

The following table shows the hyperfocal distance for the Sony RX100 M4 based on a circle of confusion (coc) of 0.011 mm and one-third f-numbers.

		Focal Length
		2.69	2.69	2.70	2.70	2.70	Crop Factor
f-Number		24	28	35	50	70	Equivalent
Nominal*	Exact	8.8	10.2	12.8	18.5	25.7	Actual*
1.8	1.78	3.96	5.32	8.73	17.48	33.72
2	2.00	3.53	4.74	7.46	15.58	30.05
2.2	2.24	3.14	4.22	6.65	13.88	26.77
2.5	2.52	2.80	3.76	5.92	12.37	23.85
2.8	2.83	2.50	3.35	5.28	11.02	21.25
3.2	3.17	2.23	2.99	4.70	9.82	18.94
3.5	3.56	1.98	2.66	4.19	8.75	16.88
4	4.00	1.77	2.37	3.74	7.80	15.04
4.5	4.49	1.58	2.12	3.33	6.95	13.40
5.0	5.04	1.41	1.89	2.97	6.19	11.94
5.6	5.66	1.25	1.68	2.65	5.52	10.64
6.3	6.35	1.12	1.50	2.36	4.92	9.48
7.1	7.13	1.00	1.34	2.10	4.38	8.45
8	8.00	0.89	1.19	1.87	3.91	7.53
9	8.98	0.79	1.06	1.67	3.48	6.71
10	10.08	0.71	0.95	1.49	3.11	5.98
11	11.31	0.63	0.85	1.33	2.77	5.33
Circle of confusion		0.011	0.011	0.011	0.011	0.011

*) According to the camera when used with step zoom (EXIF data used)

Note that only the light gray values can be used on the Sony RX 100 M4. The darker gray values are out of the scope of the lens because of its variable aperture.
(I determined the following maximum aperture values for the Sony RX100 M4 (equivalent focal lengths): 24 mm: f/1.8, 28 mm: f/2.5, 35 mm: f/2.8, 50 mm: f/2.8, 70 mm; f/2.8 (f/2.8 starts slightly beow 35 mm)).

Also remember that sharpness extends from half the hyperfocal distance to infinity.

Diagram

Tables show exact numbers, but are hard to read. I therefore also created a graphic from the table (coc = 0.011 mm):

Figure 2: Diagram of hyperfocal distances depending on focal length and f-number for the Sony RX100 M4 (coc = 0.011 mm)

Conclusions

All in all, I find the usefulness of these calculations rather limited, particularly considering the distance distance scale of the Sony RX100 M4. But see the chapter below for how you can overcome this limitation. Nevertheless, here are some of my "key findings":

70 mm (equiv. = 25.7 mm): Using the hyperfocal distance makes only sense for landscape photos (from f5.6 and smaller)
50 mm (equiv. = 18.5 mm): Using the hyperfocal distance makes mostly sense for landscape and city photos
35 mm (equiv. = 12.8 mm): At f/4 you can set the distance to about 4 m (2 m to infinity), at f/5.6 to about 3 m (1.5 m to infinity), at f/8 to about 2 m (1 m to infinity)
28 mm (equiv. = 10.2 mm): At f/3.2 you can set the distance to about 3 m (1.5 m to infinity), at f/5 you can set the distance to about 2 m (1 m to infinity), and at f/10 to about 1 m (0.5 m to infinity)
24 mm (equiv. = 8.8 mm): At f/3.5 you can set the distance to about 2 m (1 m to infinity), and at f/7.1 to about 1 m (0.5 m to infinity)

Setting the Hyperfocal Distance (or any Fixed Distance)

Regrettably, the Sony RX100 M4 does only have a coarse distance scale when in manual focus mode. Therefore, the question arises how you can set the hyperfocal, or any other fixed distance on this camera. This is described, a little lengthy, in the following.

Setting A Fixed Distance

A Russian Sony RX100 M1 user described his approach to this challenge to me in an email. It is based on what Alexander S. White writes in his book about the RX100 M1 in section AF/MF Control Toggle and how he uses this function for zone focusing (the same applies to the RX100 M4). The simple idea is to focus on a target at the wanted distance (which may be known or unknown...) using AF. Then you switch to MF. While White mentions this in the context of the AF/MF Control Toggle function*, you can actually do so either using the

AF/MF Control Toggle function, or the
Focus Mode function.

Both functions set the camera to the same (fixed) distance as AF did. They can both be assigned to the left or right button on the control wheel. The Focus Mode function can also be called via the menu (Shooting menu, page 4) or the Fn button if Focus Mode is included in the Fn button menu.

*) In his text, White does not make clear which of the two functions he uses. Only the context suggests that he uses the AF/MF Control Toggle function.

Of course, you can also set a fixed distance using MF, potentially assisted by the Focus Peaking and/or the Focus Magnifier/Manual Focus Assist functions. A tripod may also help to achieve more consistent results.

Unknown Distance versus Known Distance

In many cases, it is not needed that you know the value of the distance. You simply expect your target objects at a certain location and focus on this location. This is typically the case for sports photography, photos of children outdoors and indoors, other indoor shots, and street photography (although some street photographers prefer to set distance to a fixed known value).

In other situations, however, you want to know the exact focus distance. Using the hyperfocal distance is such a case, but some street photographers also like to set a fixed known distance for which they know the depth of field.

Since the Sony RX100 M1 does not offer a distance scale, the only way to ensure this, is to select a target at a known distance (you may have measured the distance to the target using a measuring tape or using other aids). This is what the Russian RX100 M1 user did, and he also found out that you have to use the Focus Mode function, not the AF/MF Control Toggle function.

Addendum: The Interplay of the AF/MF Control Toggle and the Focus Mode Functions

The Focus Mode function allows you to select between several manual and automatic focus modes (MF, DMF, AFS-S, AF-C). It is the "primary" method to select the focus mode, can be accessed from the menu (Shooting menu, page 4), the Fn button menu if assigned to it, and also from the left/right buttons of the control wheel if assigned to them.

The AF/MF Control Toggle function switches between AF and MF, that is, in both directions, and might be regarded as a simplified version of the Focus Mode function. It can be assigned to the left/right buttons of the control wheel. In fact, it allows fast and easy switching between manual and automatic focus, but it is only meant for temporary use and sets the camera into a "specific mode." This is revealed by several indicators:

The state of the AF/MF Control Toggle function cannot be stored in a memory locaction, only the state of the Focus Mode function can.
If you set the Focus Mode function to AF and switch to MF using the AF/MF Control Toggle function, the Focus Mode function is disabled (grayed out) in the menu and in the Fn button menu (if assigned to it). However, it displays the current focus mode (that is, MF). It is enabled again, if you switch back to the original mode that you set with the Focus Mode function.
The same is true for the other way round (starting with MF, switching to AF, ...)

References

DOFMaster Website
Schärfentiefe und Bokeh by H. H. Nasse, Zeiss, 2010; in German
Alexander S. White (2015). Photographer’s Guide to the Sony DSC-RX100 IV. White Knight Press, Henrico, Virginia (ISBN: 978-1937986476, paperback)