Public Lab Research note


Improved configuration: Arduino driven servo with CHDK for aerial panoramas

by patcoyle | May 25, 2014 07:10 | 111 views | 3 comments | #10512 | 111 views | 3 comments | #10512 25 May 07:10

Read more: i.publiclab.org/n/10512


What I want to do

Incorporate suggestions on initial results for Arduino control of Parallax servo with CHDK for aerial panoramas. [Also the new commets on this note.]

My attempt and results

I incorporated Chris Fastie's suggestions on the initial results:

For single servo (rotation only) panoramas, make a jig to hold the camera sideways to capture more of the scene with the camera in portrait position.

IMG_4542.JPG

IMG_4543.JPG

IMG_4546.JPG

IMG_4547.JPG

Alternatively, I could have reconfigures it like it is offered at Brooxes.

BEAKcanon3web.jpg

Slow the speed of the servo, hopefully to settle the camera for the shot at that speed. This video shows results of varying servo rotation speed, duration of rotation, and delay before triggering camera again.

This video shows results of trying to incorporate the additional suggestions Chris made:

You could probably rotate just a bit more with each step.

For time to have camera save, another second or so delay could be safer.

Here is ground-based test video. I also tried setting the shutter speed to 1/800 second per the comment by Chris.

However, looking at the images, I didn't get it right. The exposures vary, are slower than 1/800, and the images are blurry. For example:

IMG_0406.JPG

So, that needs attention.

Restored CHDK defaults, then reset remote shutter parameters and retested. Here's the sketch:

CHDK_100_ms1450_dly4.ino

Better. Images ok, PhotoShop Photomerge panorama looks reasonable.

A495_auto_ground_test__Panorama1.jpg

I still need to revisit setting the shutter speed to 1/800 second per the comments by Chris.

I flew it with the revised configuration. The PhotoShop Photomerge panorama shown as the main image looks reasonable.

As the video indicates, the Delta Levitation behaved better at altitude, but dove to the ground after I had the camera down.

Mathew Lippincott commented that the controller looks like it can do dual camera triggers. In the past, I've used the simpler sketch to just trigger two cameras and it may be possible to get two into this "Beak" rig, but it looks tight. I expect the Titan 2 dual-camera rig from Chris Fastie would be a better set up.

Questions and next steps

See what other improvements are needed.

Why I'm interested

The flexibility to modify the sketch to adjust speed and timing is benefit of Integration of simple computing capability into our projects.


3 Comments

That last setting in the video looks like it might be getting useful. I think the photos will still have more overlap than they need, so you could probably rotate just a bit more with each step. I can't tell exactly when the camera is shooting, but you must be right at the point where the camera might not have enough time. So another second or so delay could be safer. You will probably need about 15 to 20 positions to capture a 360 panorama in portrait mode with 50% overlap between photos. With a photo every four seconds, you can get the full circle in less than 90 seconds, which is a good goal.

You must have CHDK running on the camera to do this, so it's easy to set the shutter speed to 1/800. The CHDK menu options changed in the newest versions of CHDK.

Here are the old menu options:

Extra Photo Operations

  • Disable Overrides [Disable]
  • Override Shutter Speed Value [1/800]
  • Value Factor [1]
  • ...
  • Clear Override Values @ Start [ ]

Turn the other stuff on that page to [Off]

Here are the new menu options:

Enhanced Photo Operations

  • Disable Overrides [No]
  • Override Tv type - [Ev Step]
  • Ev Step Value [∙][1/800]
  • ...
  • Disable Overrides on Startup [ ]

Deselect the other stuff on that page [ ]

Reply to this comment...


Thanks Chris, very helpful.

Reply to this comment...


I've tried to address these points with the additional video in the note. Tried to add as comment, but need to take Markdown 101 over ;->

Reply to this comment...


Login to comment.

Public Lab is open for anyone and will always be free. By signing up you'll join a diverse group of community researchers and tap into a lot of grassroots expertise.

Sign up