Samsung NX1000

[Coadey]

I just finished building a rig from scratch for around 600 euros. I decided on a Samsung NX1000 and built a motorized turntable both controlled from an Arduino.  The platform has 28 marked positions picked up by a photocell that triggers a capture and rotates between positions automatically, with a chroma key screen for scripted masking.

I've learned a few lessons about the NX1000 in this setup so far:

• With the 20-50mm kit lens, the highest MTF and least flare is at f5.6 or f8.
• In Single Drive mode, full manual and SuperFine JPG, photos take 750ms to capture (including 200ms shutter press) on a UHS SDHC card (SanDisk Extreme Pro 95 Mbps).
• In Continuous Drive (low) mode, it can grab 12 photos in 3.5 seconds, then pauses 7.2 seconds to write them out.
• I need to use 4 x 400W halogen lamps with soft boxes to get decent exposures with continuous lighting.

I'm getting pretty good scans with just a single camera (around 40,000 points on a person), but need to make some improvements. It seems 2 cameras would be optimal to capture finer details. Here's what the trigger circuit looks like (pretty easy to adapt to trigger multiple cameras at once):



The Arduino sketch just needs this in the setup():

Code: [Select]

int cameraTriggerPin = 45;
pinMode(cameraTriggerPin, OUTPUT);
digitalWrite(cameraTriggerPin, LOW);
And you trigger a single capture with:

Code: [Select]

digitalWrite(cameraTriggerPin, HIGH); // Trigger camera
delay(200); // Wait 100ms+ for camera to detect trigger
digitalWrite(cameraTriggerPin, LOW); // Stop trigger
delay(550); // Wait for camera processing to recover
You could wire up the D- pin if you wanted to trigger auto-focus separately, but the NX1000 will focus before it snaps a photo anyway (if AF is enabled and AF Priority is on - but I recommend manual focus). 

Practically all Micro USB cables and extensions (USB "On The Go" / OTG) out there only have 4 wires connected through.  I've found this is the best place for 5-wire cables:  http://www.usbfirewire.com/uextendmicrob.html

Here are the other parts to do this solderless:

http://proto-pic.co.uk/usb-microb-plug-breakout-board/
http://proto-pic.co.uk/n-channel-mosfet-60v-30a/
http://proto-pic.co.uk/68k-ohm-1-4-watt-resistor-pack-of-20/
http://proto-pic.co.uk/breadboard-mini-self-adhesive/
http://proto-pic.co.uk/solderless-headers-10-pin-straight/

As Mala pointed out, the USB remote trigger works in modes other than WiFi, so you're limited to capturing to the SD card.  But using a trigger is much better than the app-controlled WiFi Remote, since that mode has practically no control (full auto).

I really appreciate seeing all the work others have done.  I can share more about my setup if anyone's interested.

Edit:

Here is one way you can adapt this to trigger multiple NX1000 cameras at once.  Please note I haven't tested this, and if you're using long USB cables the voltage drop might prevent it from working.  Feedback appreciated:



Coadey

[mala]

Hi Coadey,

Nice work you've done there.
Any chance you can show us some of your captures?

Cheers
Mala

[mwillis]

Coadey, very very nice.  Please keep up us in the loop.

Thanks!

[andy_s]

Yes Coadey - this looks very nice, thanks for sharing. I'd sort of forgot about the NX1000, instead investigating a mixed chdk point&shoot / DSLR solution. I'll have to look at this again. Getting the images back to a central location remains a big problem for the multi-cam setup...

[andy_s]

Coadey - but as a low cost low cam [manual image collection] startup solution - it's beautiful ! -

"I can share more about my setup if anyone's interested."

Anything - preferably everything 

[hsmith]

Very elegant solution!  I'd love to see some of your scans, especially how you deal with subject movement.

Congratulations!!

Harold

[Coadey]

I'd sort of forgot about the NX1000, instead investigating a mixed chdk point&shoot / DSLR solution. I'll have to look at this again.

I settled on the 20 MP NX1000 versus other APS-C mirrorless models as it seems to be a sweet spot in price vs IQ/performance for ?260.  The Sony NEX-5R with its 16 MP sensor was a close second, with its better ISO, but at ?460 it was less ideal (and can only use an infrared remote).  The Nikon D5100 uses a similar 16 MP Sony sensor and supports tethered USB, so it could be a good option too at around ?400.

Getting the images back to a central location remains a big problem for the multi-cam setup...

With the Arduino it would be possible to switch between remote trigger and USB host functions (via a shield) to download images, but I haven't explored that yet.  I only have the Photoscan Standard license which can't script model creation, so there's still manual work involved anyway.

I'd love to see some of your scans, especially how you deal with subject movement.

I've tried to dampen as much inertia as I can with high ratio gear boxes, but I haven't been able to eliminate it fully or turn the table slow enough to support continuous capture (which seems to be ideal).  I need to rebuild the table now that I've hashed out the limitations.  Of course the entire scan has to be done as quickly as possible so the subject doesn't fidget, and sitting is better than standing.  How is everyone combating this?  I'll try to post some scans at some point.

Thanks for the feedback.

[andy_s]

I strongly suspect that a Non Rigid Alignment software solution will cost you a lot more than simply buying some more cameras and tripods / poles....

as far as I know it is included in Artec Studio 9.0

[meshmaster]

I strongly suspect that a Non Rigid Alignment software solution will cost you a lot more than simply buying some more cameras and tripods / poles....

as far as I know it is included in Artec Studio 9.0

I don't wish to sound negative, but the non-rigid solution as it is implemented in Artec Studio is pretty limited to be honest.

Regards,

J

[andy_s]

I don't wish to sound negative, but the non-rigid solution as it is implemented in Artec Studio is pretty limited to be honest.

Regards,

J

Good information meshmaster - thanks. I had been thinking it might be what the folk at ten24 had been using to get some nice results.

[meshmaster]

I don't wish to sound negative, but the non-rigid solution as it is implemented in Artec Studio is pretty limited to be honest.

Regards,

J

Good information meshmaster - thanks. I had been thinking it might be what the folk at ten24 had been using to get some nice results.

Don't get me wrong, the tools are helpful and I'm happy to have them, they are just not quite the magic bullet that some think.  It will only be helpful under certain circumstances and from my experience those are not the most frequently encountered in daily produciton.  I know that here we rarely use it.

Best Regards,

J

[mala]

With the Arduino it would be possible to switch between remote trigger and USB host functions (via a shield) to download images, but I haven't explored that yet.

This is what I was kinda thinking as well..(guess you are basically talking about switching the resistor in/out ) although I'm not too sure if the camera is going to like this very much...the other little problem is that the camera needs a button press to start pc connection unless there is a way round this ?
Please do post here if you get this approach to work.

[Coadey]

With the Arduino it would be possible to switch between remote trigger and USB host functions (via a shield) to download images, but I haven't explored that yet.

This is what I was kinda thinking as well..(guess you are basically talking about switching the resistor in/out ) although I'm not too sure if the camera is going to like this very much...the other little problem is that the camera needs a button press to start pc connection unless there is a way round this ?

Right, while the camera tolerates the USB switch, it does need user interaction to choose "computer" versus "printer" on the host connection.  Upon switching back, it defaults to playback, so a shutter press is needed to get it back to capture mode.  An actuator could do the button press but I don't really want to go that far yet.

A true remote capture with a Nikon is going to be better for a serious workflow, but unfortunately at 2-3x the cost. I'm hoping Samsung steps up their remote app or we get a CHDK-like option.

[mala]

By the way...Google --> Samsung NX1100

Seems somebody posted info a bit early

Doesn't seem that different as far as I can tell...but does mean the NX1000 might get even cheaper.

[andy_s]

@ Coadey - bit busy at the moment, sorry I haven't got back to you yet.
Like most things 3d so far, I never took the "eyefi" option to experimental stage, but there is a forum matrix bullet time topic that shows it may work for a large number of cams.
 
@ Merry - interesting