Messages

1

General / Re: Texture scanning function

« on: January 04, 2020, 09:01:32 PM »

Hi there

you can try with another workflow ( it's the one I use )

Take pictures of your patern with a flash, always perpendicular to your subject.  ( a cloudy day without flash is better )

Then use metashape to create an orthophoto which will be your diffuse map

Put it into photoshop to select the best part and  make it tilable

Use materialize to create all your maps ( normal, metallic, AO, ... )

From my own experience its the best way
It looks strange to use RTI process because you can bake your textures with most of 3D modeling programs ( Blender can do it )

Other thing, if you create this for 3D model viewing ( like sketchfab ) 8k texture is good enough,  and make sure that the algorithm which stitch your pictures to a 160mpx pictures don't create artefact.
As I said, from my own experience, taking 7x24mpx pic and an orthophoto from them looks always better than algorithmic big pictures ( A7RIV, S1R, .. )

2

General / From cylinder to plane

« on: February 18, 2019, 08:25:47 PM »

Hi there !

I scanned a cylindrical object, i'm looking for a solution to generate a planar orthophoto from the perimeter of the object, to unfold it in a way ..
Is that possible ?

Thanks a lot !

3

General / Feedback & tips for metalic surfaces

« on: January 04, 2019, 10:28:49 AM »

Hello there,

I'm on a tricky project and I'm looking for tips !

I've to scan a set of aluminium / pewter tubes ( around 60-70 tubes ) for a metrological project from an orthophoto.
It have to be quite precise, mainly for their positions from each other.

What I can do and what I have  :

- Spots
- Polarised filter (useless ATM )
- Flash
- Controled natural light/shadow
- Photoshop for raw

What I can't do and what I miss :

- Direct operation onto the surface ( spray, ... )
- moving the tubes on a turntable

These tubes are in a wood structure so there are some nice non-metallic marks

The result must be an orthophoto from the mesh

I've done a first attempt, 60% them are really bad, 20 % just bad and 20% quite good. Don't understand why some are goods.

Is there anyone with a good idea to improve my process ?
I thought that I could use something like projected light pattern onto the tubes ...
Replacing white burned part of the tubes to another color in photoshop ...

An idea ?
Have a good day 

4

General / Re: Question on Camera Equipment

« on: June 13, 2018, 12:36:23 PM »

Hi Gianni,

I have this lens on a a6600 for my macro-photogrammetry process since 10 months

Here is my feedback :

 Of course this lens works and shows good results but its a bit tricky 30mm for 1:1 ratio, you need to be something like 2-3cm to the front on the lens to the object to reach this ratio. If it's a compact object no problem but if its not, you'll not able to have 1:1 everywhere on your model.
There are few chromatics issues with this lens when the object is grey.
Always use MF, FF is not so accuracy, maybe its better with a 6300-6500
I also use that : https://www.photo24.fr/walimex-pro-magic-arm-28cm.html pretty cool

Actually, i'm looking for a 100mm macro canon or 105 sigma, with a commlite canon > sony E
But a second hand sony E 30mm can be found for 90-100€, at this price, for a first try its perfect

If you have more questions
Good day

5

General / Re: Infinite loop

« on: February 04, 2018, 11:45:51 AM »

Hi roni,

It must be a memory problem, not enough !

Close all your others apps or do your process in lower quality.

Good day

6

General / Re: undesired objects on orthophoto

« on: February 04, 2018, 11:43:03 AM »

Hi Karsten,

Thank you for your solution, I found something who make me improve my orthophoto

My wall is pretty plain and straight, it must work with a simple shape like this. So : 

- I do all the steps in low quality ( aligning, dense cloud, object ) and the points and tie points too ( half than a normal process )
- I flip my model to see the back of it ( its a surface, so the back is just a mirror without objects front of it ) to process the orthophoto

The quantity of undesired objects is low, but there is still few fantomatic textures,

- I found the problematics pictures and hide the undesired parts with masks.

Its ok !

Long but working.

If in my orthophoto process, i can choose " middle " method instead of mosaic ( not sure of the terms ) but the general quality is very poor.

Good day !

7

General / undesired objects on orthophoto

« on: February 01, 2018, 03:50:14 PM »

Hello people

I'm trying to generate an orthophoto of a wall with a scaffolding front of it.
I'm trying to make it disappear to just have the wall.
I've pictures of the wall behind the scaffolding.
My problem is : even if i make it disapear, some pieces of it stay like a ghost ( low opacity but viewable ) on the orthophoto.
The dense point cloud was made in high quality and dept, the model too. I don't see the scaf'  on the pointclound and on the low quality texture model.

is there any tricks ?

I've something like 700 pictures, it'll takes me a century to hide, manually the object.

I tried to do the orthophoto of the back of the wall but, even if the result is better, there are always some problems.

Thank a lot

8

General / Re: Mixing short and long focal

« on: January 27, 2018, 12:30:33 PM »

Hello Alexey !

I tried some other process, it seems to work with a little bit less points limit, liaison points limit ( from 40000/4000 to 30000/3500 ) and 2 markers only on few each kind of pictures ( wide and short focals ).

I'll tell here the quality result of the dense point cloud.

Sure my pictures have the same level of details, i just want to " break " the perspective, not going deeper in details.

Thank you

9

General / Mixing short and long focal

« on: January 26, 2018, 01:25:50 AM »

Hello people,

I'm actually trying something with a building ( 15m height ) i haven't got any material to go so high, so i took my 100-300m sigma to go 20m far from the building and take pictures, of course, it didn't work, i have searched on the forum, but didn't found something interesting...

Is that impossible to mix short ( 24mm ) and long ( 150mm ) focal ? no tips ? no manual process ?

Actually, my point cloud look like the building collapsed ...

thanks !

10

General / Choose opacity of point cloud

« on: July 09, 2017, 04:28:28 PM »

Hello,

Is that possible to change the opacity of a dense pointcloud ?

I have an in and out object, i want to view the interior points behind the exterior to draw a plan. both are very denses so i can't see throught
I know that some soft like pointcab or others can do it .

Thanks a lot

11

General / Re: Orientation of a wall for orthophoto

« on: June 25, 2017, 02:01:43 PM »

Hi Blackbyrde

You have to use the marks of photoscan
Tools > marks > print marks

Then, at least on a A3, you print them ( 4 by page ), stich on the ground of your wall and take your pictures.

Marks are generated in vectpr .pdf, so with an app like illustrator, you take the distance between each point precisly.

Doing your process and after photo align or dense point cloud, select Tools > marks > detect marks

You'll have your 4 marks named by a number that you can see above your printed marks.

Then in your  references panel > marks you'll see columns X Y Z(m) ( you have to clic on the " see original values" button, just on the right of " refresh " ) Take one of your mark as reference X 0, Y 0, Z 0 and then write the distance from each other points to this reference point, the ones you took from illustrator. Then clic on refresh and your model will be aligned with this artificial coordinates.
Start your build orthophoto and select marks in your projection plan.

Tips :

- stich your A3 papier not on the " earth " ground but on your building ground like on the first step to improve your Z axis ( 90° from X axis to Z )
- your reference mark ( 0,0,0 ) could be the 90° angle of a rectangle triangle.
- make sure your XY XZ YZ marks axis following building axis


You have to improve yourself this workflow.
You can use Autocad to generate a .csv, using trilateration and improve your artificial coordinates.
If you want a perfect result, you'll have to use some tools like laser.

Good luck

12

General / Re: buying lenses for photogrammetry in archaeology

« on: May 14, 2017, 03:43:16 PM »

Hello Dukytony,
As Dave Martin says, take a look on others manufacturers,
I use a Sigma too, 24-70mm EX DG HSM and, for now, i don't found a better compromise between price/quality/using experience ( and I have test a lot ! ). IMO, fixed focal is ok when you have a lot of money to buy multiples one.

I do sometimes some archeological projects ( dolmen, caves, tomb, ... ) and going at 50-70 mm can be really useful.
try to found one with a small focus distance, under 50cm.

Good luck !

13

General / Re: single, dual gtx 1060 or single 1070, 980

« on: May 01, 2017, 12:47:21 PM »

Hello,

Can I ask you why using that kind of big GPU ?
Which step need that ?

I have a r7 1700x, 32go DDR4 and a GTX 660 and its pretty fast in all steps, even with 500+ cameras.
Sometimes freezing with 70m dense cloud ...

Thanks

14

General / Shooting high objects

« on: November 05, 2016, 02:26:16 PM »

I wondering how do you do to shoot high object/construction, from 8 to 30m high with a good accuracy ?

Without UAV of course,

Mast, ladder, zoom lens, ... ?

15

General / Re: Nice results using a ring flash!

« on: September 23, 2016, 11:50:06 AM »

I'm doing one ring light for my 82mm diam. ( 24-70mm ) sigma with 3x100w LED For something around 80€

It's a little bit heavy ( around 800gr/ 400g fanless [ if its ok ] ) and my 40D + Sigma around 1.5kg.

3x LED ; 3x booster 12-35V ; 1x power supplies 240>24v 20A; 3x Ventirad ...

I've 3Dprinted a foot button to use it like a flash.

i'll do a front filter with " plexyglass diffusant " ( http://www.rapid-catalogues.com/plexiglass/product706_plexiglas_blanc_diffusantmax_3050x2030mm.html ) when i'll be very close to the object.


It will cost me 100€ max
Everything is ready, i'm just waiting the LEDs !