Messages

31

General / Re: Investing on a PC

« on: November 01, 2013, 10:54:01 PM »

Xeon platforms will give you the ability to run several processors. Having 24 cores running at 3 GHz would certainly improve the cpus contribution on chewing data - but that costs money! I would probably switch to the LGA2011 socket and the Intel 4820K - I think that would give you more "bang for the bucks" since you already have decided to put some hefty gpu in there. The Asus P9X79 WS gives you four PCIe 3.0x16 slots and the option to use 8x8 Gb's of RAM - if you need to. The extra RAM will let you use your computer for other things aswell when processing in PS - without beeing afraid to touch it in case anything freezes. The extra PCIe slots lets you play with more graphic cards - say; if you borrowed a couple from frends to experiment.

32

General / Re: Investing on a PC

« on: November 01, 2013, 06:04:12 PM »

Yes, - more so than spending the same amount of money on a faster cpu.

33

General / Re: Software for reverse engineering?

« on: November 01, 2013, 05:58:55 PM »

Thank you very much for taking the time, Eric. It seems to me that Rhino can be a good allround too for working with meshes, making illustrations and even some 2d-drawing. Theres also some software called Alibre design and BricsCAD that seems reasonably priced. Guess I have to do a whole lot of reading to understand the differences, and what these programs can do.

Added:
Unfortunately I didn't get to try the t-splines - and if I had I would probably just been staring at those icons not knowing what to do with them ;-) . I guess there will be some work to transform into nurbs anyways. I'm just lazy, and was hoping that there would be some software that did it automagically.

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General / Re: Investing on a PC

« on: November 01, 2013, 03:21:23 PM »

Can the process get faster if it use more ram?

No, I guess not, - but its nice to have some "headroom". If you read some of the other threads about hardware on here, you will find that the GPU(s) is the key to speed in Photoscan.

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General / Re: Investing on a PC

« on: November 01, 2013, 12:43:43 PM »

I doubt that you will be able to complete those tasks with 80+ high res pics in 20 mins on any of todays "consumer hardware". In case you want to process larger datasets, the amount of RAM seems to be the only limitation fo PS to get the job done. You could consider a mainboard with 8 slots for RAM-chips, like the ASUS P9X79 to be able to upgrade in case you hit the limits. That mainboard also comes in two versions where the more expensive one can take more graphic cards - if you want to upgrade in that direction

Added: In another thread David Cockey gave this very useful tip on how to overcom ram limitations:

I have only run into memory limitations with build geometry. My work-around in that case is to:
1) Align
2) Duplicate the resulting chunk
3) Adjust the "box" in each chunk so that it only covers a portion of the geometry, with the chunks overlapping.
4) Build Geometry in each chunk.

36

General / Re: Workstation question

« on: October 31, 2013, 05:53:17 PM »

Our workstation has an Intel i7 3820, four hyperthreaded cores (shows as eight) in PS. It is mildly overclocked to run at 3.8 Ghz. The GPU is a Geforce GTX 680 with 4Gb's of RAM. In some stages of the processing the GPU does over 80% of the work. I guess you could run it without the GPU-help, but in our case it saves us some processing-time.

I did a little batch test for you with ten pics, with and without the GPU, and timed them to compare. Batch contained: aligning (High,disabled,40000,no), dense cloud(Medium, Aggressive, no), mesh (arbrit, dense cl, Extrapolated, low) and textures (generic, all cams, mosaic, 4096, 1, no) and saved between each step. Results with GPU: 4 mins, 15 secs.

Changed settings to only CPU and restarted PS. Added another chunk and imported the same files as the first one. Ran batch with same settings as the test with GPU. Results without GPU: 11 mins, 28 secs.

37

General / Re: What cameras/lenses are preferable for photoscan?

« on: October 31, 2013, 04:12:57 AM »

Heres a link to a model of an exhaust-system for a ship engine we are working on. This part has been out of production for several decades, and we cant find a good spare part. It has to be made from cast iron, but the sand-forms needed doesnt exist anymore. To show the form-maker what kind of job he is bidding on, I hung the part in a crane and shot it in both .jpeg and raw. I tried to use the jpegs, but gave up on them after seeing the sparse cloud. With the raw files the very dark inside of the muffler gave enough detail to form pretty decent surfaces. I sprayed water with chalk-powder inside the muffler too, but the oily grime turned most of it black. I really didnt pay much attention to how I shot either, and had a lot of flares in the pics shot towards the ceiling. About 130 pics, and the last 15 masked because I bumped into the muffler so it started moving.
https://sketchfab.com/show/b7b3ba35d9bc4ae69290e9306cdc0e11

Added: The muffler is sea-water-cooled and has water-cooled lids on the ends. I guess he tricky part for the maker of the molding forms, will be the water-jacket inside the walls of the muffler.

38

General / Software for reverse engineering?

« on: October 31, 2013, 02:08:08 AM »

Photoscan has given our restoration-wharf a great tool too document vessels in 3D. The next step for us now, is to find good software for turning these meshes into nurbs/cad. I'm not really sure about the terminology here, but i guess the goal is to turn the mesh into some sort of mathematical shapes. I have played around a little in Rhinoceros, but we havent decided on buying it yet. I like the fact that Rhino seems to be able to handle a whole lot of different formats - but I have no clue of what other options we have. Autocad seems to be out of reach because of the price.

Our goal, I guess, is to be able to make 2d/3d-drawings from objects. There was a plug-in for Rhino that could slice the mesh-model into sections, but these "cuts" were made from lines of cuts through faces in the mesh. If they in some magical way had turned into nurbs that would have been great. Also, if there was some rhino-plugin that would let me draw chines directly on the mesh that would also been great. Rhino also has some plugins for computing hydrostatic data from ship hulls, and we have used Delftship for this task so far, but it doesn't seem to work well with mesh-files.

I dont know what the difference between Rhino and cad-software is - is there any?

I hope someone can help us with some pointers on what would be the best investment for us. What fairly priced options do we have?

39

General / Re: What cameras/lenses are preferable for photoscan?

« on: October 31, 2013, 01:19:24 AM »

I just have to thank you guys for the tip about shooting in RAW and the correct chromatic abberation and light up shadows and dark areas and darkening brighter areas before exporting to .jpg in Lightroom. Thats difinately going to be part of my workflow hereafter - getting great results here!

40

General / Re: Setting coordinate system via markers

« on: October 25, 2013, 08:33:01 PM »

Ahh - thank you, Alexey.
I think I'm getting there... :-)

41

General / Re: Setting coordinate system via markers

« on: October 25, 2013, 07:35:07 PM »

Hi Alexey, and thanks for taking the time.
Do you want me to have "View Source", "View errors" or "View Estimated" active for that screenshot?  In "View source" all markers are x=0, y=0 and Z=0 - and big errors.

42

General / Re: Setting coordinate system via markers

« on: October 25, 2013, 06:52:25 PM »

I'm new to the professional version of P.S. I've been making models of ship-hulls that are worked on in our wharf with photoscan standard, and setting coordinate system and size in other software. I'm trying to do this in P.S. Pro now, but cannot get my head around it. I want to set the waterline at the stern as the 0.0.0 coordinate, and the waterline at the stem on the x-axis, y and z = 0. A third marker on the waterline on one of the sides, for instance the 7.3.0 coordinate should give the rotation around the x-axis.

I've been reading every post on here with "coordinate" in it, and trying to find out from the manuals how to do it - but it seems like theres something I'm missing. Please help me on how to achieve this -  and please excuse me if this is explained somewhere else.

43

General / Re: What cameras/lenses are preferable for photoscan?

« on: October 16, 2013, 09:06:24 PM »

Ikercito:  I was also playing around with the Kinect a while ago, and hopefully the drivers are updated now. There where to sets of drivers which I had to switch between to use different software with it - almost drove me nuts   Got some nice results with a program from Faro (Scanect og Scenect), and some with the toolkit that Microsoft provided. To let the sofware track the movements I had to move veeery sloooow. There's a new Kinect coming with better resolution from what i understand, but i guess the range will be about the same - after all its just a toy, but interesting technology though.

We have tried laserscanning here at the wharf, but the prices for the equipnet and software makes that stuff utopic. From what I can tell, Photoscan/photogrammetry even does a better job in our case. I tried to compare meshes from the two in CloudCompare, and the model from Photoscan agrees with the laser where the laser has been scanning directly towards the hull. The lasers precicion seems to decrease with the angle towareds the object  - i'll ad some illustrations. - The conditions were horrible for the laser though. Lots of scaffolding and tight space around the boat, and as you can see in the pics, the ones that did the scanning haven't been able to register the pointclouds properly either.

Added: With photogrammetry we can do the geometric documentation whenever it fits us, and not under horrible conditions because the appointment with some company says so. - Also we are supposed to take pictures of everything anyways while we are doing these restorations.

Since I'm already way off topic. Is there any cameras that write tilt- and compass-data as exif info? Couldn't that have been useful in photogrammetry?

44

General / Re: What cameras/lenses are preferable for photoscan?

« on: October 15, 2013, 11:12:12 PM »

Chadfx: So far I've done it all directly from jpgs, but I'll certainly dive into Lightroom hereafter. I'm pretty new to photography and photoscan, and learning as I go, - and just now I learned a whole lot from your link. I've been around f16+ - I'm always using a stand anyways. Someone told me - the more aperture the sharper, but reading all those lens tests made me suspect there might be a sweetspot. Great info!

I'll stick with the Sigma 10-20 for now - or at least until I have learned more, but the D90 has to serve among the craftsmen - I tried a D5100, and found that flip-screen to be very handy - also the focus, light measurement and whitebalance seemed to be better than the D90.

45

General / Re: What cameras/lenses are preferable for photoscan?

« on: October 15, 2013, 01:13:24 PM »

Chadfx: I suspect I have DOF-issues when working in engine compartments, as tubes, rails and other "thin" stuff in the middle of the room seems to "blur away" in the model. I know i need better lighting, and should probably pay more attention to texturizing shiny surfaces. I've been using chalk and colour-powder mixed in water, sprayed on and left to dry before shooting - which seems to help, but this is not a good solution either since these rooms are very narrow and I need to be able to move around while shooting. I also suspect I may have used too high aperture in my tests. - Unfortunately there's no rental companies here in Norway, that carries the gear I want to try.

I've been considering the Nikon D5200 because of it's flip-screen and focus abilities and a Tokina 11-16 f/2,8, which gets very good reviews. The Olympuses also have flip-screens, and is said to have very reliable focus.

JMR: That's such a GREAT offer! Would it be too much to ask if you could take some shots of the lens-calibration patterns too  I've seen that Lumix G Vario 7-14 online, but got the impression that its lens-calibration would only work on Panasonic cameras. I'm not familiar with mft cameras, never tried one either. Wifi could come in handy. Do you have any suggestions for what camerabodies i should consider? OM-D EM-1 and 5, and the EP5 all seems great - bit pricey though, as we would have to afford that lens too  The Zuiko is about 20% more expensive than the Lumix 7-14 - is it worth the extra money?