Citation

BibTEX

@misc { npapadopoulos_macro-photography_using_a_mobile_phone,
  author = "Nikolaos Papadopoulos",
  title = "Macro-Photography using a Mobile Phone",
  howpublished = "\url{https://www.4rknova.com/blog/2020/06/14/macro-photos}",
  month = "06",
  year = "2020",
}

IEEE

[1] N. Papadopoulos, "Macro-Photography using a Mobile Phone",
    https://www.4rknova.com, 2020. [Online].
    Available: \url{https://www.4rknova.com/blog/2020/06/14/macro-photos}.
    [Accessed: 01-03-2025].

Introduction
Cotton Swab
Aloe Vera Plant
Sea Urchin Shell
A4 Paper Sheet
Pen
Blade
Syringe
Plastic Sheet
2N2222 NPN Transistor
References / Further Reading

Introduction

I recently stumbled upon an interesting DIY article^[1] where the author used a very simple trick to enable a regular mobile phone to take macro-focus photographs. This looked like fun, so I tried to replicate the experiment and take some shots of my own.

The idea is simple. A water droplet is placed on top of the phone’s camera to act as a magnification lens. In macro photography, the ratio of the subject size on the sensor plane to the actual subject size is at least 1:1^[3]. Note that this makes focusing rather challenging, as the depth of field is quite small. The size of the droplet will determine the focal point and therefore the level of magnification that can be achieved. Generally, the smaller the droplet is, the closer the focal point is to the sensor.

The water droplet was made with a syringe but the same can be done with a cotton swab. To achieve the best results, the droplet should cover the entire surface of the aperture, with as little liquid as possible, without breaking surface tension^[2]. The purity of the liquid plays a fairly important role in getting clear pictures. I ended up using filtered tap water in this instance.

With the camera setup and ready to go, it’s time to pick a subject. Organic and translucent materials such as plant leaves are a good choice, mainly due to the complexity of their surface structures. Furthermore, it’s easy to shine light through such materials, allowing to capture a fair amount of detail. Obviously, there are limitations to the visual quality that is achievable with this setup but the results are still very impressive.