Question 1

What do camera lens mounts mean, and can you adapt lenses between systems?

Accepted Answer

A lens mount is the **mechanical and electronic interface** between a lens and a camera body — and the two numbers that define it, **throat diameter and flange distance**, determine what can be adapted onto what.

**Flange distance** is the gap between the mount and the sensor. It is the governing constraint:

**You can adapt a lens with a longer flange distance onto a body with a shorter one**, because the adapter simply adds the difference back as physical spacing.

**You generally cannot go the other way** without optical elements, because there is no room — the lens would need to sit closer to the sensor than the mount allows.

**This is why mirrorless changed everything.** Removing the mirror box shortened flange distances dramatically, so mirrorless bodies can accept almost any older SLR lens through a simple adapter, while SLR bodies can accept almost nothing.

**Throat diameter** affects how wide the maximum aperture can practically be, and wider mounts give designers more freedom — part of why newer mirrorless systems produce very fast lenses.

**What an adapter does and does not preserve:**

**Same-brand adapters** usually preserve everything — autofocus, aperture control, stabilisation, metadata — though autofocus may be slower than native.

**Third-party electronic adapters** vary considerably, with autofocus reliability the usual compromise.

**Dumb mechanical adapters** carry no electronics, so you get **manual focus and manual aperture only**, and no metadata. Fine for older manual lenses, which is mostly what they are used for.

**Optical adapters** with elements — including focal reducers, which shorten the effective focal length and gain a stop of light — genuinely change the image, and quality varies.

**Crop factor still applies.** Adapting a full-frame lens to a smaller sensor gives a narrower field of view; the lens has not changed, the sensor is capturing less of the image circle.

**What to check before buying:** whether the adapter supports autofocus with your specific lens, whether stabilisation still works, and whether infinity focus is maintained — a cheap adapter of the wrong thickness loses it.

Question 2

What does the f-number on a lens mean?

Accepted Answer

The aperture — how wide the lens opening is relative to its focal length — and the scale is counterintuitive in two ways that confuse almost everyone at first. The two confusions: Lower numbers mean

Question 3

What is the difference between optical and digital zoom?

Accepted Answer

Optical zoom moves glass. Digital zoom crops the image. Only the first adds detail. Optical zoom physically changes the lens's focal length, or switches to a different lens with a longer one. Light

Question 4

How does camera autofocus actually work?

Accepted Answer

By one of two fundamentally different strategies — measuring how out of focus the image is, or hunting until it looks sharpest — and the difference explains why some cameras snap to focus instantly

Question 5

Does sensor size matter more than megapixels?

Accepted Answer

Yes, by a considerable margin — and the megapixel number is the figure most heavily marketed and least informative about image quality. What megapixels actually determine. How many pixels the image

Question 6

What is the difference between optical and electronic image stabilisation?

Accepted Answer

OIS moves hardware to counteract shake; EIS crops and adjusts the image in software. They address the same problem differently, and increasingly appear together. Optical image stabilisation (OIS).

Question 7

What features should I look for in a smartphone for photography?

Accepted Answer

To find the best smartphone for photography in 2023, look for high camera quality, lens versatility, low-light performance, image stabilization, and advanced software capabilities.

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