The Batis 2/40 CF has the Close Focus ability, ie. it can focus close, but how close is ‘close’ exactly? If you read the specs sheet you learn that the minimum focusing distance is 24 cm (0.78ft). The minimum focusing distance is calculated from the sensor and if you are wondering how close the lens will be from the subject in practice, then the answer is 14 cm (0.45 ft), that's called 'a free working distance'. With the moderately wide angle lens like the Batis 2/40 CF the free working distance is always pretty short and if you are photographing living things like butterflies and such, they are likely to be disturbed about the lens being up there so close (that's why true macro lenses are often quite a bit longer). However, another consideration for a shorter focal length is that they often provide more three-dimensional and immersive pictures that contain something about the context as well (while true macro lenses tend to flatten the perspective). This is something that I meant yesterday when I wrote that Close Focus ability offers a kind of another picture type between normal and macro shots: close up pictures that show the details but also something for the surroundings as well.
So, the minimum focusing distance is 24 cm (0.78ft) and the free working distance is 14 cm (0.45 ft), but actually none of these numbers answer the essential question: how large will small objects, such as wedding rings, legos, or broccoli appear on your pictures? That's why in ZEISS's specs sheet there is also 'a magnification ratio' which describes how will the certain size of an object appear on your camera's sensor, compared to its size in real-life. The Batis 2/40 CF has a magnification ratio of 0.30x (or 1:3.3 if you prefer to read it this way). This means that in minimum focusing distance an object with the width of 10cm (3.93 in) will appear with the width of 3 cm (1.18 in) on camera's sensor. Or another way to think about it is to say that an object with a width of 12 cm (4.72 in) and a height of 8 cm (3.15 in) will completely fill the image frame with a full frame Sony A7 body (with a crop sensor, such as A6500, the same values are 7.8cm (3.07 in) and 5.2cm (2.05 in)). So, how the magnification ratio is related to Batis 2/40 CF's 'Close Focus' ability is simple: the closer one can focus, the more magnification a given lens will be able to achieve — which makes sense because closer objects appear to become larger.
Yet another way to demonstrate this is today's picture. This picture was taken pretty much at the minimum focusing distance 24 cm (0.78ft). The flowers were very small, which might make it difficult to sense the right proportions, but on purpose I put a one single matchstick there for better evaluation. Well, obviously matchstick's size can vary in different parts of the world so I had to measure it also to make this demonstration more clear: the matchsticks length is only 4cm (1.57 in) which is, for example, about the same as diameter of the wristwatch's face. So, like I said, it's not actually in the macro range, but still very good for all kinds of close up shots.
And you can of course go even closer if you are willing to crop the picture. Especially with the A7RII & A7RIII bodies and with their 42 megapixel sensors this might give you some extra headroom for close ups. For example, you can use the crop mode and end with the pictures with even better magnification ratio (0.45x) and still have 18 megapixel files (which can still easily be used for A3 prints). Here is one picture of blueberries at minimum focusing distance and which I have cropped just a slightly (but less than the 1.5 crop factor). As you can see, we are getting close to macro range where you start to pick up all kinds of details which are invisible to eye in everyday life. I'm not saying you should pursue for macro range pictures with the Batis 2/40 CF as it's not designed for that, but in some cases it's not very far either.
Finally you might wonder if the magnification ratio of the Batis 2/40 CF is better than with other similar lenses. In about same focal length there are many lenses with similar minimum focusing distance and it might sound, at first, that the Batis 2/40 doesn't bring too much on a table. But like I wrote earlier the minimum focusing distance isn't a very good variable for describing the magnification potential of a lens (because it also depends so much about the field of view). So, to inspect this side of the argument I listed all relevant lenses which are about same focal length and put them in order starting with the greatest magnification ratio.
ZEISS Batis 2/40 CF | 0.24m (0.78ft) | 0.30x
ZEISS Batis 2/25 | 0.2m (0.66ft) | 0.19x
Sony FE35/1.4 ZA | 0.3m (0.98ft) | 0.18x
ZEISS Loxia 2/35 | 0.23m (0.75ft) | 0.17x
Sony FE 24/1.4 GM | 0.24m (0.79ft) | 0.17x
ZEISS Loxia 2.4/25 | 0.25m (0.82ft) | 0.16x
Sony FE 50/1.4 ZA | 0.45m (1.48ft) | 0.15x
ZEISS Loxia 2/50 | 0.45m (1.48ft) | 0.14x
Sony FE 55/1.8 ZA | 0.5m (1.64ft) | 0.14x
Sony FE 50/1.8 | 0.45m (1.48ft) | 0.14x
Sony FE 35/2.8 ZA | 0.35m (1.15ft) | 0.12x
As you can see the Batis 2/40 CF differs quite a bit from the rest when it comes to its magnification potential even though the minimum focusing distances are quite similar. I have to give it to ZEISS: compared to competition I think this is a pretty nice way to differentiate from the others as it adds versatility of the lens and offers a different point of view to many scenes – really, very easy to justify once you've tested it in practice.