How to Buy a Used Camera Lens — Fungus, Haze, Autofocus and Mount Fit

Good lenses often hold their value well, which makes a second hand lens one of the smartest buys in photography. But glass problems are easy to miss, and a lens is useless if it does not fit your camera. Here is what to check — condition first, then compatibility.

Fungus

Fungus is the biggest risk in humid places like coastal India. Shine a phone torch through the lens from the back and look through the front. Fungus shows up as thread-like or web-like growth inside the glass. A lens with active fungus can spread spores to other gear — avoid it unless it is priced as a repair project.

Haze

Haze looks like a milky fog between elements and lowers contrast. Use the same torch test; a clear lens looks crisp and clean.

Scratches and coating marks

Small marks on the front element rarely show in photos. Scratches on the rear element matter much more because they are close to the sensor.

Autofocus and stabilisation

Mount the lens and focus back and forth between near and far subjects. It should be quick and quiet. Switch stabilisation (IS, VR or OSS) on and look through the viewfinder at a long focal length — the image should settle.

Zoom and focus rings

Rings should turn smoothly with even resistance. Grinding, sticking or play suggests a drop or sand inside.

Aperture blades

On lenses with a manual aperture ring, look through the lens while turning the ring. On electronic lenses such as Canon EF, mount the lens and press the depth-of-field preview button (or take photos at different apertures). The blades should move freely and be free of oil.

Mount and contacts

Check the metal mount for wear and the electronic contacts for corrosion.

Will the Lens Fit My Camera?

A lens only works on cameras with the same mount. Check the mount on the product page against your camera before you buy.

Mount

Fits

Notes

Canon EF	All Canon EOS DSLRs	Works on Canon mirrorless (RF) bodies with Canon's EF-EOS R adapter, keeping autofocus
Canon EF-S	Canon APS-C DSLRs only (e.g. 1200D, 800D, 70D, 7D Mark II)	Does not fit full-frame DSLRs such as the 6D or 5D series
Canon RF / RF-S	Canon EOS R mirrorless bodies	RF-S lenses are made for APS-C bodies such as the R100, R50 and R10
Canon EF-M	Canon EOS M mirrorless bodies (e.g. M50)	A separate mount: does not fit EOS R or EOS DSLR bodies
Nikon F (FX and DX)	Nikon DSLRs	DX lenses are made for APS-C bodies; on full-frame (FX) bodies they use a cropped area
Nikon Z	Nikon Z mirrorless bodies	F-mount lenses work on Z bodies with Nikon's FTZ adapter; older AF and AF-D lenses focus manually on it
Sony E / FE	Sony mirrorless (A6000 series, A7 series)	FE lenses cover full frame and also fit APS-C bodies
Sony A	Older Sony DSLR/SLT bodies (e.g. A58, A68)	Not the same as E-mount; needs an adapter for mirrorless bodies

The Nikon autofocus trap

Entry-level Nikon DSLRs such as the D3200, D3300, D3400, D3500, D5100, D5200 and D5300 have no autofocus motor in the body. They autofocus only with lenses that have their own motor, such as AF-S lenses. Older AF or AF-D lenses fit, but you will have to focus manually. Newer AF-P lenses are not fully supported on some older bodies (some need a firmware update), so check Nikon's AF-P compatibility list for your camera before buying one.

Not sure? Ask before you buy

Send us your camera model on WhatsApp and we will confirm whether a lens fits and autofocuses before you order.

Buy one that is already checked

Every second hand lens at WorthyTen is checked for fungus, haze and scratches and tested on a camera body before sale, then covered by a 1-year warranty.