Secret from practice: Not all 100,000 miles are equally useful!

In the workshop, I often see identical cameras with the same EXIF number (for example, 80,000 frames), but in absolutely different technical condition of curtains.

Why does the shutter of a carcass look worn out to the limit after a wedding or studio photographer, and why does the shutter of a landscape photographer look like new guy? Let's look at the physics of the process.

1. Continuous shooting (Continuous High / CH) and heating the lamellas

When a reporter or sports photographer presses the trigger in `CH` mode at 8-10 frames per second, The kinematic unit for cocking the curtains works at the limit of its capabilities.

• During long series (40–50 frames at a time), friction of the lamellas on the guides will cause local overheating metal and Teflon elements.
• The lubricant in the hinges heats up, liquefies and is forced out of the working zones of the friction pair. Wear increases with exponential!

2. Pulsed Light in the Studio (High Speed ​​Sync HSS/Auto FP)

In the studio, when working at ultra-fast shutter speeds with the **Auto FP (High-Speed Sync)** mode, the shutter does not open completely - there is a narrow gap running between the first and second curtains. At this moment, the flash generator gives a series of pulses.

The shock vibration load on the return springs of the curtains at shutter speeds of 1/4000 - 1/8000 sec is maximum.

Comparative wear for different types of shooting

Filming genre	Episode intensity	Wear rate per 100k frames
Landscape/Architecture	Single frames (S)	Minimal (shutter will last 300k+)
Studio portrait (HSS flash)	Singles + Short Series	Medium-high wear
Report / Sports / Weddings	Continuous Series (CH)	Maximum (impact wear of hinges)