Editing RICOH THETA Z1 DNG Images with GIMP, darktable, and PTGui

If you don’t have Adobe Lightroom, you can use darktable and GIMP on Linux or Windows/Mac to load and edit the DNG file from the THETA Z1. After light and color editing, you can stitch the images with PTGui on Windows/Mac. From version 11.13, PTGui includes a template for the RICOH THETA Z1.

Workflow

Move Files Onto Workstation

Load Images Into darktable

On my Ubuntu 18.04 system, I have darktable installed. The DNG image automatically loads into darktable when I click on the image

Export from DNG to JPG or TIFF, PNG

Export Files from lighttable -> export selected

After export, you can also manipulate the image in GIMP. The example below is intentionally over-exposed.

Stitching With PTGui

RICOH has an official plug-in for Adobe Lightroom that works great. If you do not have Adobe Lightroom you can use PTGui 11.13 or newer for stitching.

In THETA Desktop application.

Using PTGui on Linux to Stitch Z1 Images

Using Ubuntu 18.04 and Play on Linux with acceleration disabled.

Viewing preview of stitched image with PTGui Panorama Editor.

Export Panorama

Test with included PTGui Viewer

Testing 360 view on Linux using Google Photos and Chrome.

Navigation works great on Facebook.

Summary

GIMP and darktable can be used to edit the DNG images. The commercial PTGui on Windows/Mac can be used to convert the dual-fisheye to equirectangular.

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Nicely done, you can even batch stitch the images if you make your own template in PTGui 11 pro

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@Svendus, I think the developer, Joost, including a template for the THETA Z1 DNG image to allow batch stitching. I haven’t tested it yet.

In the test above, I am using the template included with PTGui 11.13. I didn’t need to create any control points.

that is right but i think the template must be made for the specific camera do to small differences in the hardware https://svendus.se/blog/?page_id=2229#.XLHvqBaezYU

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We need your help and knowledge in fully exploring the workflow with PTGui and batch processing. :slight_smile:

Oh, do I need to straighten the image with the mouse?


Why are you looking at this screen? To verify the stitch line?

Why are you cropping the images?


When you set the control points, the images are horizontal and you select the left sphere in image 1 and the right sphere in image 2?

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  1. Oh, do I need to straighten the image with the mouse?
    not necessarily i think the THETA Z1 are quite good in level!

  2. Why are you looking at this screen? To verify the stitch line?
    No it is the two images when we mowed the building to the center!

  3. Why are you cropping the images?
    We have to crop the images do to small differences in the camera hardware
    to be able to get a good precise batch stitch on hundreds of images
    NOTE we even have an indoor template!

  4. When you set the control points, the images are horizontal and you select the left sphere in image 1 and the right sphere in image 2?
    Yes on (Xaomi MiSphere camera) and the (Garmin Virb 360 camera) the image and copys are horizontal but the Raw files from (Insta36 ONE X) they are Vertical
    Remember the images are 1 and 2 number 2 are a copy
    You have to mark the Control points in the overlapped arias only
    many mistake this and do mess up the stitching.
    we sadly do not have the money for a THETA Z1
    because we just bought a DJI Mavic Air drone 1100$ in sek =10 175.2925 Swedish kronor
    But we do have a lot of fun anyway :rofl:

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@codetricity if you sent uss some THETA Z1 Rawfiles we shall try to batch Stitch them in PTGui 11 Pro

I did one attempt a Linux workflow screencast below. I need to improve the PTGui workflow section. It shows the basic steps, but not a “good” configuration.

Im getting strange error?

What is the error?

PTGui is only officially supported on Mac/Win. I used “Play On Linux” to get it working on my Ubuntu 18.04 system. I also disabled hardware acceleration on my Linux machine. If you have Windows/Mac, it should be more stable.

Update June 2, 2019

Another alternative to PTGui and the THETA Stitcher from RICOH

Where do I get the Z1 template for PTGui? I don’t have it available on my computer.

It’s built into PTGui. You don’t need a separate download of the template.

On the page below, search for THETA Z1
https://www.ptgui.com/support.html

6.43. How can I stitch images taken with a 360° one shot camera in PTGui?

Several single shot 360° panoramic cameras exist, producing a single image containing two circular fisheye images side by side. PTGui supports several of these cameras, including the Samsung Gear 360, Xiaomi Mijia Mi Sphere, Yi 360 VR and Ricoh Theta Z1. If an image from such a camera is loaded into PTGui, PTGui will actually add the same image to the project twice, with different cropping circles and masks, positioned at -90 and +90 degrees yaw.

While this already results in a roughly stitched image, the images still need to be aligned for perfect stitching. This is due to small differences between individual cameras of the same type, resulting in different small offsets of the image circles. You only need to perform manual alignment once for each camera, the result can be stored in a template and re-used. To create the template:

  • Start a new PTGui project
  • Load a picture from the 360° camera. It’s best to use a photo taken outside, with no objects close to the camera, to prevent parallax. PTGui will automatically load the same image twice.
  • Go to the Control Points tab and add a few control points. Image 1 is the leftmost or topmost circular image; Image 2 is the right hand or bottom one. Just click once on a point in image 1, then once on the same point in image 2. It can be helpful to use the Generate Control Points Here function: Shift+drag to create a rectangle, right-click in the rectangle and choose Generate Control Points here. Often this will find control points automatically. Avoid placing control points on objects close to the camera since these will suffer from parallax.
  • Optimize the project (menu Project -> Optimize). The result should be ‘good’ (otherwise you’ve probably misplaced a control point somewhere)
  • Open the panorama editor (Control+E on Windows, Command+E on mac) and check the result.
  • Do File | Save As Template and choose a suitable name.

For subsequent images the template can be used instead: Load a picture from the 360° camera, then do File | Apply Template and select the template created above. The images are aligned already and the panorama can be stitched by going straight to Create Panorama.

The template can also be used for batch conversion using the Batch Builder (PTGui Pro only):

  • Tools | Batch Builder
  • Click ‘Detect panoramas…’
  • Method: Multiple panoramas per folder with a fixed number of images
  • Source folder: (select the folder containing the unstitched images)
  • Image file extension: leave empty, or enter ‘JPG’, ‘DNG’ (if applicable)
  • Images per panorama: 1
  • Press Detect Panoramas
  • Use template: (select the template you created above)
  • Select ‘the batch stitcher will not run Align Images’
  • Press Generate Projects
  • Finally, PTGui asks whether the projects should be sent to the Batch Stitcher. Press Yes and all your images will be converted.

Keep in mind that all cameras with multiple lenses will produce images with parallax. Some stitching errors will be unavoidable, especially in small rooms or with objects close to the camera. Also see: Q4.13