What do you guys think of using the new BLK360 as a laser scanner to combine with images from a DSLR through RealityCapture? Anyone got to test the pre-production BLK360? Any thoughts on the unit and if you plan to incorporate it into your business/workflow?
It looks to be a very interesting easy to use and versatile device, however it’s accuracy looks to be very poor in comparison to it’s bigger brothers.
From there own website faq.
H OW ACCURATE IS THE BLK360?
The BLK360 accuracy is 6mm @ 10m
I wonder if our $15000+ would be better spent running around taking more photo’s instead, for a better quality result. over 1/2cm out for accuracy makes me wonder if the BLK would be more of a hinderance than help. I guess it depends on quality of project you are hoping for. It could help data acquisition time a lot.
In comparison the faro and sigma devices do ±1mm accuracy at even a greater range. - They do cost many times the price which makes them inaccessible to most.
I’ll wait for someone else to test before investing
All very good points. My thinking is that exactly, it might help lower data acquisition time and improve accuracy of the 3D model over just stitching images. I might miss something while taking photos that the 3D scanner can fill in. I’ve played around with Reality Capture demo version, and the software often doesn’t accept a good percentage of the images that I capture, even though there’s a lot of overlap and redundancy. It seems to struggle with shots at variable distances. I’d want all the help I can get so that I don’t have to go back and reshoot, at a reasonable price (even 15k is expensive).
My thoughts exactly - about the accuracy. To be honest, 6mm @ 10m is nothing worth considering for metrological purposes. And the point density is also quite limited. In my experience, the accuracy of photogrammetry is quite high if the image set is good. It’s not easy to make a comparison because distance doesn’t really apply here. I would say - without having any concise imperical data - that the accuracy lies within a few pixels, especially in x and y of the images. I once had an error of 1 cm in one of my theodolite aquired ground control points right in the middle of a well covered model of about 10x10 m. I tried everything to make it and fit but RC was battling my efforts up to the point of almost breaking up the component. There was no way I could convince it otherwise - with the closest other GCP maybe 1,5m away. The error remained at about 10mm, whatever I did, even with ridiculously high weight. The mistake was that I did not set the reflector height right. So that proved to me that the internal accuracy is enormously high. Usually, I achieve sub mm accuracy, which is below real world measuring accuracy of the theodolite. Only the margins of a model can be tricky since there are “loose ends”.
Anyway, concerning your troubles with alignment, that’s a bit of a weakness in the learning curve in my view. Because RC wants to be coaxed with the right settings. Exif grouping is one of the most important in my view.