Housing for Creality Nebula Camera in Qidi Plus 4 Printer

Qidi Plus 4 printers include a camera, but its image has low resolution, poor focus, and markedly foggy image depth. The stock camera is also positioned too high to view print nozzle. In contrast, the Creality Nebula camera has markedly better picture and requires no driver or firmware changes to take the place of the stock camera. Unfortunately, despite its diminutive size, the Nebula is still too large to fit within the printer where one can view the entire print bed and nozzle without being crushed by the print head.

This camera housing/mount replaces the Nebula camera housing with a slimmer one. The mount also sets pitch and yaw to aim camera correctly while still avoiding impact from the print head.

Plate in orientation as in picture. No supports should be needed. Print in PETG with 2 perimeters, 5 top, 3 bottom layers. 15% gyoid infill. Thin wall detection should be on. Perimeter generator classic.

If your print bed has poor adhesion, you may need to add a brim. On my printers, neither brim nor supports were needed to print the housing, if plated in the orientation shown in plating pict.

Remove internals of Nebula camera by prying off its rear panel. Two screws hold the PC board in place. Those same screws hold the Nebula internals within my mount. Cut off the camera's rear plastic plate, taking care not to harm the cable nor its strain relief. 

Tip: When placing cover on mount, position the cable inward so thinner portion of strain relief is clamped. Route cable through channel in cover first, then put cover onto housing.

There is no need to disconnect cable from back of Nebula circuit board. You can route the cable through printer - USB A connector first.
 

TURN OFF PRINTER AND DISCONNECT MAINS BEFORE INSTALLATION OF THIS HOUSING AND CAMERA WIRING.

New camera housing mounts on plastic nub of interior, upper, right of Plus 4 door opening. Borrow one M3 x 6 self tapping screw from Qidi main fan mounting plate to secure the mount and its cover. The screw clamps the housing and cover onto the plastic nub. 

On some Plus4's, Qidi used a longer screw to secure door magnet. If that is the case on your printer, the magnet screw (from front of stud) blocks entry of M3 screw into back of stud. The easiest solution is to carefully slice open a circular flap of the foam overlying magnet screw head. Then you can remove the magnet screw, cut it 3 mm shorter. Reinsert shortened screw to secure magnet. Lay back the little bit of foam you lifted to once more hide the screw head. That will give you enough space in back of stud to secure camera.
 

Route new camera USB cable following stock camera cable. It is easier to zip tie new USB cable to existing camera cable rather than removing/reattaching wire clips. Rear of Qidi printer must be opened to feed USB connector from print chamber into rear of machine. Unplug the existing camera USB cable and replace with new camera cable. Use the same USB port (2nd from top one)

Option: If you do not use WiFi, you can also remove the WiFi dongle and save significant CPU load. You can connect second camera into what was formerly the WiFi USB port

For best results, also set camera resolution and frame rate in webcam.txt settings file. Find the line 24 camera_usb_options and change it to… 

24 camera_usb_options="-r 1920x1080 -f 10 -d /dev/v4l/webcam0"
 

----------- BEGIN TWO CAMERA HINTS
If you wish to use more than one camera, connect both stock and Nebula cameras into main board. I do not use WiFI. So I plug one camera into instead of the WiFi dongle. 

Look up your USB video device by-id paths in Fluidd. Your by-id paths may differ from mine.
There is no need to SSH into printer to get by-id paths. Open Fluidd system information page. Click on USB icon to see devices. Select video and click refresh icon. Fluidd will present all your connected camera info. Copy the path by-id for each camera.

In webcam.txt change lines 24 and 72 to use your by-id path and specify port. They should look like the below examples.

webcam.txt

24 camera_usb_options="-r 1920x1080 -f 10 -d /dev/v4l/by-id/usb-UnionImage_Co._Ltd_CCX2F3298_1234567890-video-index0" 

72 camera_http_options="-n -p 8080"

webcam2.txt (You must create webcam2.txt)

24 camera_usb_options="-r 1920x1080 -f 10 -d /dev/v4l/by-id/usb-0735_0269_SN0001-video-index0" 

72 camera_http_options="-n -p 8081"

Camera definitions in Fluidd MUST use your actual printer IP address in URL if using more than one camera. Also, Set FPS target 10 for cameras

Stock 

URL stream = http://xxx.xxx.xxx.xxx:8080/?action=stream

URL snapshot = http://xxx.xxx.xxx.xxx:8080/?action=snapshot

Nebula 

URL stream = http://xxx.xxx.xxx.xxx:8081/?action=stream

URL snapshot = http://xxx.xxx.xxx.xxx:8081/?action=snapshot

----------- END TWO CAMERA HINTS
 

Save settings and restart webcamd service for your camera settings to take effect. (Three dots icon in upper right of Fluidd)

Screen capture shows picture from Nebula after mounting. The Nebula automatically adjust exposure. Bright cover of toolhead causes camera to darken overall image. Darkening toolhead cover would lighten image.

One additional feature of the Nebula is it switches to B&W infrared if you turn off the printer chamber light in the dark. 

v3 moves cable channel to exit bottom for easier cable routing and pitch down from original 10 degrees to 15 degrees down angle. This is maximum without impacting toolhead cover. Slight changes to improve printability of parts.

Main version has camera down pitch 15 with 38 degrees left yaw. 

A slightly more tilted down version with down pitch 18 left yaw 38 is also provided, but requires sanding down of one LED to fully clear toolhead cover. If LED is not sanded down or removed, there is a slight touch with extreme forward, rightward corner movement, but not during pure forward motion filament cutting.

Better tutorial for adding cameras to Fluidd is here https://github.com/guykuo/Plus4-Wiki/tree/main/content/add-cameras-to-qidi-plus4