Do machine vision cameras come with a lens: what to order

You are speccing your first vision stations, the price list shows one line per camera body, and nothing tells you whether a lens is included. It is not. An industrial area-scan camera arrives as a sensor behind a threaded mount, and the lens is a separate item you choose and order for each station. That split is deliberate: the lens sets your field of view, working distance and image sharpness, so it belongs to your application rather than to the camera. Below is the decision, the two matching rules — mount and sensor format — the focal-length arithmetic with one worked example, and the case for proving a single camera before you order the fleet.

No, the camera does not ship with a lens

"GigE" names the data connection, not the optics. A GigE Vision camera moves finished frames down a gigabit cable; USB3, 10GigE and CoaXPress do the same job at other speeds. None of them forms an image. The lens gathers the light reflected from your part and projects it onto the sensor; the sensor turns photons into electrons; the interface carries the bytes to your software. Power a camera without a lens and it still streams — a flat grey wash, because nothing is focused on the sensor.

So commit to the line item: one lens per camera, chosen per station. The industry works this way on purpose. Two stations can run identical camera bodies with 8 mm and 50 mm glass; a fixed built-in lens would kill that flexibility.

What is in the box, and the six exceptions

A typical area-scan body ships with the sensor, the mount, a cap for that mount and its documentation. The lens, the interface cable and the lighting are separate order lines; plan them into the same purchase so the first station runs on day one. In our camera finder, the lens-mount filter lists six of 1,287 area scan cameras under integrated optics — bodies with the lens built in and a field of view fixed at the factory. Those suit stations whose geometry never moves. Everything else, and any station where the field of view might change, takes a separate lens.

First matching rule: the mount

The mount is a thread standard, and the camera body fixes it. C-mount is the workhorse: a 1 inch-32 UNS thread at a 17.526 mm flange distance, found on the overwhelming majority of industrial bodies, with the deepest lens stock to match. The C-mount thread and diameter standard covers the thread itself. CS-mount sits 5 mm closer to the sensor at a 12.526 mm flange; a C-mount lens reaches focus there with a 5 mm ring, which is why the variant is picked at order time — see CS-mount versus S-mount camera variants.

The big formats go threaded, not bayonet-less. The 25 MP MV-CH250-25TC-F-NF is an APS-H F-mount body on 10GigE, and the 25 MP MV-CH250-90YC-M58S-NN is a CXP-12 camera with an M58 thread. On the lens side, the LS-FFL-1676 is a 60 mm M58 lens rated 65 MP over a 214-1536 mm working range. Start in the machine vision lenses finder filtered to your camera's mount; if the body is C-mount, that single filter is all you need here.

Second matching rule: the sensor format

The lens must throw an image circle at least as wide as the sensor diagonal. Fall short and the frame corners go dark — vignetting you cannot fix in software. Format names are nominal, so work from the diagonal:

The lens finder's image-circle filter uses these buckets, so a 1/1.7" camera takes any 8–11 mm circle or larger. The lens sensor format explainer goes deeper on formats. The second number is the lens's megapixel rating: it should meet or beat the camera's. A 20 MP body like the MV-CS200-10GC is a 1" sensor on a C-mount. Pair it with glass from the 16–22 mm image-circle bucket and the 16–25 MP rating class, not the reverse. The physics behind that rating is in Airy disk size and the diffraction limit — the smallest spot a lens can focus sets how small a pixel is useful.

The focal-length arithmetic

With mount and format fixed, focal length comes from three numbers you already own: sensor width, field of view and working distance.

The quick form, f ≈ WD × sensor width / FOV, drops the (1 + m) term and reads high by exactly m — 3.7% at the magnification in the example below, which is why it is fine for choosing between stock focal lengths. To check a lens the other way round: FOV = sensor width × WD / f.

The same formula is worked end to end on a packaging line in the working distance and field of view walkthrough. If your target focal length lands between stock values and you must hit it exactly, lens spacers and shims shift magnification in fine steps.

Worked example: a 200 mm part at 500 mm on a 12 MP GigE camera

The inputs, each with its source:

• Field of view: 200 mm — the part plus placement tolerance.
• Working distance: 500 mm — the clearance above the conveyor.
• The camera: the LS-CMR-0053, a 12 MP GigE camera, 1/1.7" sensor, C-mount.
• Sensor width: about 7.4 mm, nominal for a 1/1.7" format.
• Pixel count: the USB3 variant of this camera, the LS-CMR-0166, lists 4000 × 3000 pixels at 30 fps on the same IMX226 sensor.

Pixel pitch works out to 7.4 mm ÷ 4000 px = 1.85 µm per pixel. Now the sizing:

1. Magnification: m = 7.4 mm ÷ 200 mm = 0.037.
2. Focal length: f = 500 mm × 0.037 ÷ 1.037 = 17.8 mm.
3. Stock values bracket it at 16 mm and 25 mm. At 25 mm the field of view is 7.4 × 500 ÷ 25 = 148 mm, and the 200 mm part no longer fits. At 16 mm it is 7.4 × 500 ÷ 16 = 231 mm, a 15% margin. Take 16 mm.
4. Sampling: 231 mm ÷ 4000 px = 0.058 mm per pixel, so 58 µm on the part. A 0.5 mm feature spans 8.6 px — comfortable to detect and workable to measure. A 0.25 mm feature spans 4.3 px — detection only. Below about 3 px per feature, change the set-up, not the software.
5. Exposure: at 0.5 m/s of conveyor, one pixel of blur is 58 µm, so t = 0.058 mm ÷ 500 mm/s = 0.00012 s, about 120 µs. The LS-CMR-0053 runs at 9 fps, so the frame rate allows far more; motion, not the sensor, sets your exposure.

Order a 16 mm C-mount lens rated at least 12 MP with a format of 1/1.7" or larger. The LS-FFL-0567 is a 16 mm C-mount lens, 20 MP rating on a 1.1" format, F2.8-22, distortion under 0.3%. A 16–22 mm image circle clears the 9.3 mm diagonal twice over, so the same glass can later move to a 1" body.

Focus wide open, then stop down one or two clicks; the aperture f-number and depth-of-field trade-off explains what each stop buys and what it costs in light — and at a 120 µs exposure you will want that light. Decision for this station: a 12 MP GigE body with a 16 mm C-mount lens, exposure near 120 µs with lighting to match. If the 0.25 mm marks must be measured rather than detected, narrow the field of view or double the pixels before the fleet order.

Board cameras: the M12 case

Board-level and embedded cameras trade the C-mount thread for M12 (S-mount): smaller, lighter, and focused by screwing the lens in and locking a ring — the M12 thread pitch and focus physics covers how far one turn moves focus. Five of 1,287 area-scan cameras in the finder take M12, and the M12 board lenses range holds 195 lenses, 177 of them M12. Their image circles top out in the 8–11 mm bucket, so treat 2/3" as the sensor ceiling. M12 glass generally costs less than comparable C-mount optics because it serves smaller sensors; the trade is resolution and format headroom.

The LS-MBL-0118 is a 12 mm M12 lens at F5.6, rated 12 MP on a 1/1.7" format. The LS-MBL-0012 is a 5 MP low-distortion S-mount lens, 12 mm, for 1/1.8" sensors.

For the full walk — format, focal length, IR-cut — read M12 lens selection for board cameras. To size one from scratch, choose a board camera lens by working distance and field of view does it step by step, and thread basics are in board camera lens mount sizes.

Prove one camera before you buy the fleet

Before a multi-camera order, buy one complete station: camera, lens, cable, light. Get a sharp frame of the real part at the real standoff — focus the lens at working distance, not on the bench — then confirm pixels per feature, exposure versus motion, and how ambient light behaves. One week with one station kills the classic first-order errors: wrong focal length, wrong image circle, not enough light for the exposure the line speed allows. If you are scoping cost per station, this rundown of entry-level industrial machine vision cameras is a useful reality check on what bodies cost before glass.

Then multiply. Request the fleet by quote for volume pricing, and once one station passes, in-stock items ship within one business day. Every camera carries a 3-year warranty minimum. More camera set-up reading is collected on the cameras topic page.

Order checklist

Before the camera:

• Fix the mount — C-mount for most area-scan bodies; it decides which lens shelf you shop.
• Note the sensor format and resolution; the lens must clear the diagonal and the megapixel rating.

Before the lens:

• Run the focal-length formula at your real working distance; pick the shorter stock value for margin.
• Choose a manual iris with a lock ring for fixed stations; auto iris only where light truly varies.
• Check the image-circle bucket against the table above, one bucket up if a bigger sensor may follow.

With the first unit:

• Focus at working distance, lock the ring, then stop down one or two clicks.
• Confirm the smallest feature spans at least 3 px, and time exposure against line speed.
• Plan physical protection — caps, mounts, housings; this guide to lens protection for rugged shop cameras covers the floor and washdown cases.

Then quote the full count once one station passes. To assemble the whole station in one pass, start at the lens step of the configurator or browse the camera finder filtered to the mount you settled on.