The tests to perform in 5 minutes before buying a used camera

At our Ancona counter, I often see the same scene: someone arrives with a camera bought from a Facebook group, places it on the counter, and asks if I think it's in good shape. Nine times out of ten, the defect was already present at the time of purchase and was visible in less than five minutes, without any tools, just by holding the camera in hand. It's just that no one had told them what to look for.

This is the sequence I use when a used item arrives for evaluation, stripped to the bone and ordered by the ratio of time spent to defects found. It works in a parking lot, at a bar, or in front of a seller who is in a hurry. It does not replace the lab's test bench, but it tells you whether to pay or walk away.

Before you go: what to bring with you

The kit for testing a used camera body fits in a pocket and costs less than twenty euros. You don't need laboratory equipment: you just need to have with you the three things the seller, for their own reasons or by distraction, might not provide. Whoever shows up empty-handed ends up trusting words instead of files, and words cannot be checked on a monitor at home.

Empty SD card, charged battery, phone flashlight

Three items, three precise reasons.

• Your own SD card, empty and formatted. If you shoot on the seller's card, you take nothing home: the RAW files stay there, and you're left with the memory of what you thought you saw on the three-inch monitor. An empty card also prevents the opposite scenario, i.e., finding pre-existing files of unknown origin. Sensor and autofocus tests must be evaluated 100% on a large monitor, not on the camera's display.
• Charged battery, preferably compatible. "It's dead, you can charge it at home" is the phrase that ends the negotiation. Without power, you cannot read the shutter count, test the burst mode, or check the ports. If the model uses a battery you already own — which happens often when changing camera bodies within the same system — bring it. Otherwise, insist that the camera is charged before you leave.
• Your phone's flashlight. It is needed to inspect the mount, the gold contacts, the inside of the camera, and the corners of the body. In ambient light, an oxidized contact looks like a normal one.

If you have one, add a microfiber cloth and your own lens to test the mount. Nothing else. A kit bigger than that won't fit in your pocket, and you won't be taking it out.

The only non-negotiable rule: light and time

The test is conducted in daylight, calmly, while seated. Not in a parking lot at eight in the evening, not with the seller checking their watch, and not "on the fly because I have to rush." These are the conditions under which defects slip through, and you end up paying for them.

Five minutes and a power outlet: that's all you need to ask for. If they refuse, the issue isn't the camera but the person selling it to you, and it's the most reliable sign of the day. Anyone with a healthy camera has no reason to rush. It's the same pattern we discussed in the five most common mistakes made by used camera buyers: almost all of them stem from a purchase made under conditions that didn't allow for any verification.

If the meeting is at the seller's home, ask to stand near a window. If it's in a bar, look for the table with the most light. These are details that seem excessive until you try to check for dust on the sensor under a fluorescent light.

Test 1 — Shutter count (40 seconds)

The shutter count is the first test because it establishes the context for everything else. A scratch on the camera body on a unit with 4,000 shutter count tells a different story than the same scratch on one with 90,000. Read the number first, then everything else gains meaning.

However, this is not a deadline. When Canon states a shutter life of 100,000 certified shutter counts for the Canon EOS RP (priced between 520 and 600 euros in our catalog, the most affordable Canon RF full-frame body passing through our counter), they are providing a statistical median from testing: half of the units exceed that threshold, while the other half fail before it. A camera body with 15,000 certified shutter counts has consumed 15% of its declared lifespan. It is not "like new"; it is 15% used.

How to read it in the field

The method that works on most camera bodies: take a RAW shot with your SD card, open the file on your phone with a free EXIF reader, and look for the shutter count or image number field. You need your own card; otherwise, you are reading a file you cannot take with you.

• Nikon, Pentax, Sony e Fujifilm: the count is written in the file metadata; an EXIF reader on your phone will show it immediately.
• Canon: the EXIF does not contain the shutter count. You need dedicated software by connecting the camera body to a computer, so ask the seller to read it and send it to you before the meeting: on-site, without a computer, you cannot retrieve it.
• Mirrorless with electronic shutter: if the body shoots in silent mode, the mechanical counter does not increment. A camera used for two years in silent mode may show 6,000 mechanical shutter counts and have actually taken 40,000 shots.
• JPEG: many JPEG EXIFs lose the field. If the seller lets you take test shots, ask for RAW.

How many shutter counts are actually a lot

The count must be evaluated in relation to the model, never judged in absolute terms.

The Sony A7 Mark III (€800-1,000, the used full-frame with the best battery life-to-shutter count ratio) is still young at 30,000 shutter count. The Canon EOS R100 (€375-400, excellent as a first APS-C camera body) has worked quite a bit at the same count relative to its build. If you want to understand how much the count weighs on the final price, we discuss it in detail in the guide to the 7 evaluation parameters.

The count that doesn't add up

Shutter replacement resets the shutter count on some brands but not others: it depends on the service center and the year. Therefore, a low number on a visibly used camera body is an anomaly to be clarified, not good news.

A body declared at 3,000 shutter count with a shiny mount rubber and marked screws is one of two things: a reset counter after a repair, or a camera that has sat idle in a closet for eight years. In the first case, you want the repair receipt; in the second, you must check the seals and the battery. Both warrant a direct question to the seller before opening your wallet.

Test 2 — The sensor at f/16 against a white wall (60 seconds)

This is the test that offers the best return for the minute you dedicate to it. On a used mirrorless body with a few years of life, the probability of finding at least one spot on the sensor is very high: the sensor remains exposed at every lens change, without a mirror acting as a barrier. The difference between a 30-40 euro intervention and a 300 euro one lies entirely in what you see in these 60 seconds.

The exact procedure

You need any lens mounted and a uniform surface: a white wall, a clear sky, or an illuminated A4 sheet. This is the sequence.

1. Mode A (aperture priority), aperture set to f/16. If the lens goes down to f/22, even better: the more closed the aperture, the sharper and more visible the dust becomes.
2. Base ISO — 100 on most camera bodies, 200 on various Fujifilm and Panasonic models. Do not raise the ISO: noise masks small spots.
3. Manual focus completely out of focus, or set to infinity pointing at the sky. This is needed to make the wall detail disappear and leave only the sensor defects.
4. Move the camera slightly during the shutter count. Any irregularity on the wall will blur out, while the dust on the sensor remains fixed because it is attached to the focal plane.
5. Review the shutter count on the screen and zoom to 100%, then scroll through the entire image systematically: four corners and center, not just the center.

Dust, scratch, pixel: how to tell them apart in three seconds

The definitive test for dust is the blower: two puffs with the camera pointed downwards, retake the shots, and if the spots have moved, it's dust. If the mark is in the exact same pixel, it's a scratch.

The dead pixel test with the body cap mounted

Fit the body cap, cover the viewfinder, and take a 2-4 second exposure at ISO 1600. The frame must be black. A few isolated bright spots are normal on any sensor with years of use, and the internal pixel mapping will clear them in thirty seconds. However, a widespread constellation indicates that the sensor has been heavily used in long exposures or has suffered from heat: do not buy it.

On early-generation Sony full-frame models, this check carries more weight than elsewhere, as these are bodies with several years on their shoulders. A Sony A7 at 400 euros remains the most affordable way to enter the full-frame mirrorless world, but it is a 2013 body: the sensor requires careful inspection. The Sony A7r Mark II at 800 euros raises the bar with 42 megapixels and in-sensor stabilization — and it is precisely the pixel density that makes every grain of dust more visible at 100%. On both models, in our lab, sensor cleaning is part of the standard revision before the body goes on the shelf.

Test 3 — Shutter and burst (30 seconds)

Close your eyes and take thirty shots. It is the fastest test of the sequence and the one sellers expect the least, because it sees nothing: it listens. A mechanical shutter nearing the end of its life produces a different sound months before it produces a bad photo, and the ear catches it even without specific experience.

Listen to the rhythm, not the volume

Set the camera to continuous shooting, 1/500s shutter speed, and hold the button down for thirty certified shutter counts. You don't care how loud it is: DSLRs are inherently louder than mirrorless cameras, and a healthy Nikon D750 makes more noise than a worn-out Sony. What matters is that the rhythm is metronomic. Every certified shutter count must sound identical to the previous one.

The signals that matter:

• Doppio click on some shutter counts and not on others: the blades do not close in sync.
• Ritardo variabile between one shutter count and the next: buffer full (normal after 15-20 RAW) or shutter magnets struggling to release (never normal).
• Scatto che "strascica", with a metallic tail: tired return spring.

If the slowdown occurs after ten shutter count and resumes normally after two seconds, the buffer is clearing to the card. Repeat in JPEG: if the issue disappears, it was the card, not the camera body.

Black bands and half images

A shutter that jams mid-stroke leaves a distinct black band on one side of the frame. On heavily used first- and second-generation Sony APS-C bodies, this is a fault we see with some regularity, and it does not happen on command: it can appear on one shutter count out of twenty or thirty. You will never see it with three test shots.

So take the thirty shutter count and then scroll through the thumbnails quickly, not one by one. A black band stands out much more during a fast scroll than in single view. A Sony A6000 that we have at 360 euros remains an excellent first APS-C camera body precisely because we know it is healthy; the same machine bought from a private seller with 80,000 shutter count is a gamble. The same applies to the Sony a6500 at 600 euros, which adds in-body stabilization and a much larger buffer: it is the model that videomakers have used the most, and therefore the one where the thirty shutter count test really matters.

Slow and fast shutter speeds

Last five seconds. Frame the same scene and take two shots in manual mode: first at 1/4000, then at 1 second, adjusting the apertures to achieve the same theoretical exposure. The two images must have comparable brightness. If the 1/4000 shot is visibly darker or shows a gradient on one side, the first curtain is worn compared to the second. On mirrorless cameras, also test with the electronic shutter: if the times are correct there but not in mechanical mode, the diagnosis is confirmed and it is purely mechanical.

Test 4 — Autofocus, viewfinder and screen (60 seconds)

These three subsystems are tested together because they share the same sequence of gestures: eye to the viewfinder, finger on the button, thumb on the screen. In the lab, we check them in the same step, and it is advisable to do the same on-site. Sixty seconds, one high-contrast subject and one flat subject, and you have answered the three questions that matter.

AF: Test the corners, not the center

The center point works almost always, even on heavily used camera bodies. It is the most protected point and the most supported by the algorithms. The ones that truly degrade are the peripheral points and eye detection, because they rely on mechanical tolerances and a firmware that operates with less light and less contrast.

The procedure is as follows: move the AF point to an extreme corner of the frame, focus on a high-contrast subject at 50 cm, then switch to infinity. Alternate five times. You are not looking for a single error, which happens on any camera: you are looking for the hesitation, the back-and-forth pumping before it locks. Repeat on a flat, uniform surface, such as a colored wall or a closed door. If the center point locks and the corner pumps for a second, you have found something.

Electronic viewfinder: dead pixel and lag test

Aim the viewfinder at a strong light source and move the camera rapidly from left to right. Look for three things: fixed lines that remain stationary while the image scrolls, evident tearing during movement, and darker areas towards the edges. Then cover the lens with the cap and look at the black: dead pixels are only visible this way.

This is no small detail. On the Fujifilm X-H1, currently available for 650 euros with its 3.69-million-dot viewfinder — one of the best of its generation — replacing the EVF unit is an expensive intervention, and the replacement part is not always available. The same applies to the Canon EOS R at 800 euros. On these camera bodies, a defective viewfinder is not something to fix later; it is a reason to walk away from the purchase or to renegotiate the price significantly.

Screen: hinge, touch, delamination

Open and close the flip-out screen ten times and feel the play with your fingers: the hinge must hold its position without giving way under the weight of the screen. Then, slowly run a finger across the entire touch surface, including the edges, with the menu open. Dead zones are common on heavily used vlogging bodies, where the touch is the primary interface and is stressed thousands of times: the Sony ZV-1F at 400 euros is exactly this type of camera, excellent as a talking compact but with a screen that works hard.

• Peripheral AF hunting — calibration or module: from 90 euros up
• Dead pixels in the viewfinder — cannot be repaired, the assembly must be replaced
• Loose hinge — inexpensive replacement, but the internal flat cable is the real risk
• Dead touch zones — display replacement, often not cost-effective for cameras under 500 euros

Test 5 — Mount, contacts and body (45 seconds)

The shutter count can be reset with modified firmware. A crushed mount rubber, no. These 45 seconds are the part almost no one does during negotiation, and they tell you how the camera body was treated over the years when no one was photographing it for the listing.

Mount play

Mount a lens, hold it with your left hand, and try to move it laterally relative to the camera body. A micro-play perceptible only by touch is normal and was present even when new. Visible movement or a metallic click when rotating indicates a worn mount or loose screws.

On mirrorless cameras, this is the number one wear point, not the shutter. Lightweight bodies paired with heavy lenses put all the leverage on the mount: a 400-gram body supporting a 1.4 kg 70-200mm lens does the damage. The Panasonic GH4 we have for 320 euros is an opposite and instructive case: Micro 4/3 mount, short and light lenses, mount practically intact even on bodies with years of video work behind them.

Electrical contacts and sealing rubber

Inspect the gold contacts inside the mount against the light. They must be clean, all at the same height, with none recessed or bent. A recessed contact causes intermittent communication errors with the lens, the kind that don't show up in the shop but lock your aperture in the field.

Then look for the black rubber seal around the mount, on bodies that have one. If it is crushed, hardened, or partially missing, the weather sealing claimed in the technical specifications no longer exists. The replacement part is inexpensive, but labor brings the total cost to 60-120 euros.

What the rubber seals, screws, and battery compartment reveal

• Bulbous or sticky grip rubber: the camera was kept in a warm or humid environment. It's a cosmetic issue, but it tells you where it has lived.
• Stripped screw heads: someone opened it. Ask why, and ask for the invoice for the service.
• Oxidized or greenish battery compartment contacts: liquid infiltration. This is the defect that makes you walk away.
• Flash hot shoe with worn paint in the center: heavy use with flash or external monitors, consistent with a working body.

On recent bodies, the picture changes. A Canon EOS R50 V at 550 euros has been on the market for just over a year: here you are not looking for wear, you are looking for accidents. A single out-of-place mark on such a young machine weighs more than ten marks on a 2014 body. If you are considering your first step into mirrorless, we have developed the reasoning on what is physiological wear and what is not in how to choose your first used mirrorless.

Test 6 — Battery, ports and stabilization (45 seconds)

This is the only test block where a negative result should not make you cancel the purchase. Battery, doors, and slots are replaceable components with known costs: if you find a defect here, you have an argument to negotiate, not a reason to walk away. The difference from the previous five tests is that here you know the exact repair cost before even leaving the store.

The battery that drains in steps

Turn on the camera, take twenty shots in normal sequence, and check the indicator. A healthy battery loses one notch, maybe two. If it drops from 100% to 60% in twenty shots, the cells are degraded: the chemistry can no longer handle the load, and the indicator recalculates downward under stress. The typical symptom is a stepwise drop, not a gradual one.

On many Sony and Fujifilm camera bodies, the menu also displays the battery health status in three or four levels. If you find it, check it. If it's not there, the twenty-shutter test remains the quickest method.

• New original battery: 50-90 euros depending on the model
• Third-party compatible: 20-35 euros, with actual capacity often lower than stated
• Reasonable negotiation margin: the cost of the original, not the compatible one

USB, HDMI ports and card slots

Slide the card in and out three times and check if the latch engages firmly. A slot that doesn't hold the card is a mechanical issue, not a cosmetic one: the card can slip out of your bag and the connection may drop mid-write. Then, open the port cover, test the USB with your own cable, and verify that the camera responds.

On used camera bodies for video and vlogging, the USB charging port is the first point of failure, as it is plugged in and unplugged daily. The rubber flap covering it tears at the hinge: it is inexpensive to replace, but if it is missing entirely, dust resistance is compromised.

Stabilization: what "5 stops claimed" really means

The five stops declared by manufacturers are measured in a laboratory according to the CIPA standard, with a static subject and the photographer seated in a controlled position. Standing up, with cold hands and a moving subject, the real gain drops to 2.5-3 stops. It is not dishonest marketing, it is marketing measured under conditions you will never encounter.

The test takes fifteen seconds: mount a 50mm lens, set the shutter speed to 1/8 second, and take five shots handheld. At least three must be 100% sharp at 100% zoom. If you only save one out of five, the stabilizer is malfunctioning or not working at all.

On the Sony a6500 — currently available for 600 euros, the first Sony APS-C with in-body stabilization — and the Fujifilm X-H1 at 650 euros, the IBIS unit is suspended and audible. Upon startup, it produces a brief hum, almost like a mechanical click. Complete silence on these two camera bodies is a warning sign: it may indicate that IBIS has been disabled in the menu, or that the unit is jammed. Check the menu first, then listen again.

What 5 minutes can't tell you

The six tests cover approximately 80% of the defects we see coming into the lab. The remaining 20% cannot be detected in a parking lot, and anyone who tells you otherwise is trying to sell you something. It is worth knowing exactly where the method ends, because that is where you decide whether to buy from a private seller or from a shop that takes the risk on your behalf.

Defects only visible after disassembly

A camera body can pass all tests and still develop issues in the following months. These are slow-onset faults, not breakages: at the time of testing, the camera works.

• Internal oxidation — typical of camera bodies stored in basements or taken to the sea. It appears on the motherboard contacts, not from the outside. It emerges as intermittent blocks after weeks.
• Cold solder joints — a connection that holds as long as the camera remains stationary and fails with vibration or thermal shock. No bench test can reproduce it in five minutes.
• Flat cable of the tilting screen — wears out from repeated opening and closing. The screen works, but the cable is already at its limit. Replacement costs between 90 and 180 euros depending on the model.
• Hardened internal seals — the weather sealing declared in the technical specifications no longer exists. You discover it in the first rain.

What we do in our workshop

Every camera that comes through our doors is inspected at the bench before it goes on sale, no exceptions. The process is always the same: reading the shutter count from the system, wet sensor cleaning, verification of all AF points and not just the central one, inspection of the mount and contacts under the lens, battery test under real load, and shutter test at all speeds from the slowest to the fastest.

The 2-year warranty on used equipment is the result of that inspection, not a commercial promise. Those who do not open the camera bodies cannot afford a 2-year warranty: it is arithmetic, not generosity.

The question to ask a private seller

“Do you have the receipt and the box?” is not needed to verify the authenticity of the camera body. It serves to determine whether the seller is traceable and has kept track of what they own. It is an indicator of behavior, not of the product.

The second question is more useful: “Has it ever been opened?” The answer and the time it takes to give it matter. An immediate “no, never” is a data point. A three-second silence followed by “maybe once, I don’t remember” is another data point, and it’s worth more than any photo in the listing. On this topic, we’ve also written 5 common mistakes when buying a used camera.

The complete sequence in order, ready to print

Eight checks grouped into the six blocks you just read, less than five minutes of actual testing, plus the kit in your pocket: empty SD card, charged battery, phone flashlight. The order is not random: the shutter count comes first because it contextualizes everything you find afterwards, and the sensor comes immediately after because it is the most expensive defect and the one that makes you stand up and leave before wasting any more time. If the seller gets annoyed while you run the sequence, you already have a piece of information.

Take a photo of this table and keep it open on your phone while you are in front of the seller. It is not rude: a seller with a healthy camera has nothing to fear from five minutes of checks. Anyone who objects is saving you a bank transfer.

When to walk away

There are three absolute deal-breakers. Everything else is just material for negotiation.

• Black bands or horizontal lines in burst mode. It is the shutter or the sensor readout electronics. Repair costs over 300 euros when possible, often it is no longer possible on out-of-production camera bodies.
• Scratch on the filter in front of the sensor. It cannot be cleaned, it must be replaced: 200-400 euros plus labor. A scratch visible in backlight is worth more than the discount they will offer you.
• Evident play on the mount with the lens attached. If the set rotates or wobbles, the focal plane is no longer factory spec. Test it with a second lens to rule out that the defect is there.

Apart from these three, think in numbers. Dust on the sensor: 30-40 euros for cleaning, ask for a discount and buy. Worn mount rubber or oxidized contacts: 60-120 euros. Tired battery: 50-90 euros for an original one. A screen with a few dead pixels on a 500-euro camera body: live with it, don't spend 250 euros on a module. On a budget camera body, the repair can cost more than the difference with a healthy unit, and it is worth looking at what the market offers at the same price — the Sony A7 di prima serie is the typical example of a camera where a 150-euro intervention completely changes the sense of the purchase.

Frequently asked questions

If you prefer that someone else has already run the tests

If you have doubts about a purchase or need advice for your specific case, contact us. We offer free advice because we are photographers first, and because a customer who makes a poor purchase will not return to photography.

Three ways to get in touch:

• Contact form — response within 24 business hours
• WhatsApp at 342 362 3454 (messages only)
• Phone: 071 291 6347 (Mon-Fri 9-13/15-18, Sat 9-13)

And if you want to see what we have in stock right away, explore the used gear available today: every camera body is certified, comes with a 2-year warranty, and ships within 24-48 hours.

Article written by Matteo for the ReflexMania Team. Last updated: August 2026. Prices and availability refer to the time of publication.