POP2 W/RevoScan 4.0.0 & 4.0.1 looses track!

I haven’t been able to get very far scanning the bust! It’s on a slow (~ 1 RPM) turntable. RevoScan stops tracking properly after 10 to 15 seconds, never recovers(no error reported)!

System:
HP Z;640 workstation 128GB RAM, 2TB SSD, 12 core Zeon @2.4Ghz.
POP2 connected via USB3.

I have a .mp4 video of my most recent attempt, but it isn’t a format supported for upload.

Hi @Unobtainium,
Did you callibrate your scannner allready? Post your accuracy-score.
Try to get an excellent distance to your objetc.
What does your object‘s surface look like?
Is it like a mirror —> paint it
Is it verry simillar —> add markers
Is it too dark for feature recognition —> set the starter settings to dark and use a bright backround.
Some working screenshot or video would help to support you further.

1 Like

As @3DsCnR already mentioned the most important factors .
The distance is very important .

Feature Mode : Object distance not smaller than 15 cm from the POP2 to the Object
Face Mode : 20 cm
Head Mode : 25 cm
Body mode : 40 cm

Make sure your POP2 is slightly on the angle and not direct in 90 direct angle
Make sure the window light is not in front of POP2

The turntable rotation should be between minimal 60 to max 20 sec per 360 degree rotation , ideal is 30 sec rotation per 360 degree capturing 300 frames over rotation .
Do not over scan your object multiple times , it will make no difference and fasted time fusing with overlapped point clouds that will looks bad after meshing , one tourn is enough .

Since you scan the bust , there is no way it is losing tracking if you follow the steps that @3DsCnR and I mentioned .

Tracking depends of the visual features of the object , I suspect your object is too close and you lose the tracking when the object is on back of his head , take the scan away or measure the distance to minimal 15cm distance in Feature mode for best sharpness .

If still problems then you can check your calibration scores , if it is above 0.1000 then maybe good idea to calibrate , check the score 2-3 times and the lowest will be your actual score .

I have not tried calibration, will do so.
Distance from POP2 to the head was ~15cm. RevoScan rated the distance as Excellent.
The object is the white plastic bust supplied with the POP2.
Turntable speed was ~1rpm (60 sec/360 degrees) as @PopUpTheVolume suggested in another post.
In the screen capture video RevoScan tracked until frame 207, then lost it in 208. I was able to grab frames 197 & 218:


Raise the scanner and tilt it down at about a 45 degree angle to the object.

Please go away from the windows blinds , it interrupt with the scanning , please have nothing behind the objects that can be picked up but the object , you can start using 60 sec per 360 degree when you get some practice first , start with low accuracy and 0.2mm pitch point until everything works fine and you are comfortable with scanning , then you can start with the highest settings .

and as @Miamijerry already say tilt the POP2 45 degree , never straight to the object unless you already scanned top part of the object then you can, but make sure object is visible as much as possible in your depth camera preview , not partial of you will need to merge it manual .

and please no walls behind scanned objects unless there is no more blue

1 Like

@PopUpTheVolume
Thanks for the tips, greatly appreciated As you can tell, I’m a 3D scanning novice. My business is reproducing NLA parts for vintage Ferraris. My objective with the POP2 is to reverse engineer parts so I can 3D print them or print patterns for silicone molds.

away from the windows blinds ,
no walls behind scanned objects
OUCH! Didn’t anticipate this! I’m working in a very small office area with lots of stuff in the background in every direction! I can’t move my workstation setup. So I’ll have to figure something out.

You can have objects behind but not too close that the scanner can pick it up , if you can’t move it , put behind a black garbage bag or plastic in black color while scanning to cover it and problem solved . I purchased black silicone mat to put behind in my light box , a black PVC would works too .

The way you have now it would be impossible to scan anything . Black fabric will not works , only black plastic, PVC or silicone .

Try it, you will see everything will works just fine .

Good luck !

@PopUpTheVolume

Black fabric will not works
(DUH) Just found out the hard way: tried to use a folding portable photo studio that of course uses fabric.

I find the scanner gets hot after a while and then loses tracking much more.

objects behind but not too close
What minimum distance behind should be OK?

black silicone mat
Could you post a link to a source for t his?

Also IIRC seeing your light box, which thread was it in?

Thanks, that’s a good tip as I’ve been leaving mine powered on!

It get hot since it has build in processor, the aluminium casting covering POP2 working as heat dispenser , same as aluminium covers over PC RAM . The heat actually has nothing to do with tracking , I work sometimes for 10 hours and do not noticed any difference in tracking before or after . However it can shut down if the ambient temperatures are above 85F , it is not designed to work in hot weather .

20 cm distance , what is very small but my back has PVC or Black Silicone mat , my desk is by the window too but using light box with the PVC black background and it works fine .

here are links to my light box and the new silicone mat I use on my table

I wish I purchased the bigger light box for home use , with the turntable I have only object at 13 inches fit inside . I got the 16x16x16.

Thanks.
If I don’t have a light Box or some kind of backdrop how far away do walls and other objects have to be to not cause problems?

Until you don’t see anything in blue color behind your scanned object , watch the Depth Camera preview , if you see anything blue behind is not good .

1 Like

do marker dots count on the rotating platform?

Only if you use Marker mode , make sure " Remove Plane " is checked in , when using marker mode l am not using the marker plate when scanning in different modes, usually I cover it with my black silicone mat to avoid scanning .

@PopUpTheVolume Thank you very much! I did a quick set up on the dining room table table with the black plastic sheet that came with my pop 2 , and using a Samsung tablet. I was able to successfully do a couple of test scans Without much trouble at all.

I I’m still having trouble Getting the point clouds to synchronize when I rotate an object to pick up Obscured areas and holes, I just discovered your Tutorial videos on YouTube. I hope they’ll show me what I need to do to Get the point clouds to synchronize.

@Unobtainium you can use regular garbage bags too as that is what you got with POP2 lol black plastic absorbing IR light , black silicone and rubber too , so particularly invisible .

Regarding "synchronization " aka tracking of your point cloud , it all depends of the object features , if your object have lots of features then the tracking is much easier , but when there are smooth surfaces the scanner get blind spots and can’t recognise it in space and you lose the tracking . Using marker mode is the best option for trouble objects like that , as the software follows only the tracking of the markers and no more the object , however marker mode can be used only in partial Scanning that need to be merged later together , you can’t switch sides in marker mode and continue scanning .

The best is to find the proper angle where you can capture the object at once if possible , avoid scanning objects when they are only partially visible in Depth Cam preview, it asking for trouble , if the object do not fit ,change the mode and move the POP2 away , face and head mode is not for just face and head , it is for objects that have similar size too , same for body mode , you want to scan 6ft objects use body mode etc…

Glad to hear that you are progressing , take your time , you will be a pro in no time .