Create High Quality HDRI for VFX using RICOH THETA Z1

THETA Media
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Definitely JPEGs and especially stitched JPEGs are adding a lot of troubles.
But i think it possible reach same results with Theta X as Z1.

I love Logoscope work and his knowledge in colors. But sensor spectral response is not a panacea and not always work as planned. (Plus required too expensive software like Nuke to use them)

BTW, as i see there is no perfect match in renders vs photo:

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And can you add user defined EV distance? 3EV not recommended to APS-C and FF sensors but on 1inch they are definitely add too many noise. So only way to use Z1 captures is probably use two burst shots with 1EV or 1.3EV steps with Max to 6~15sec shutter speed.

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If the results of X using JPEG and the results of Z1 using RAW are the same, please share your method of creation, or compare it with a color chart shot with a different camera like we did, or compare it with a reference to see if the highlights, shadows, reflected colors, etc. match the back plate at the time of compositing and the lighting matches. Only when we can confirm that the lighting matches the backplate at the time of compositing, we can say that it is a high-quality HDRI.

At least, we would be happy to know this, because in the verification we have done, we have encountered quality problems in terms of lighting balance and reflected colors when using JPEGs.

So, going back to the original topic, I said that JPEGs are not capable of producing high quality HDRIs, with the implication that it is difficult to create HDRIs of a quality that can be used in high end VFX with JPEGs.

Sorry about this.
The difference is caused by the shader (roughness, specular) settings in the CG chart, and it is our fault for not adjusting it enough, but I think this difference is within the acceptable margin of error.
In fact, what is remarkable about this image is that the HDRI renderings produced by the full-size SLR 5D3 and Z1 are nearly identical.
This result indicates that the quality of the light is equivalent to the HDRI created by the full-size SLR.

I don’t believe the 3EV step is problematic since the RAW is used. In fact, as per the attached image, the difference in comparison to the 5D3 HDRI is slight. Noise also has little impact when used as a light in HDRI, and we have determined that a stack to remove noise is not necessary in our verification.(However, we do add denoising during the raw photo processing process)
In HDRI, it is more important to be able to accurately reproduce realistic light values than to have a clean, noise-free image.

Our plug-ins are also set up to focus on finishing the shoot faster. This is necessary both because of the need to shoot quickly on a VFX shoot and to minimize the effects of crowd and cloud movement.
If you need a clear, noiseless HDRI shot, which we use in reflections, we too think you need to increase the number of brackets as you have said, or shoot with a SLR.

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What’s the best way we can help promote your plug-in? Is there any way for you to make money from your plug-in? We can help promote it with things like this blog post and social media.

It’s better for continuous improvement of the plug-in if the developer can make some money in some business model. Happy to help you promote your business if we can.

This site receives sponsorship from RICOH. As part of that, we can try to promote the great work of the developers.

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I clearly understanding weakness of Theta X comparing to Theta Z1.
My point only about your definition of “High Quality HDRI” that make Theta users confusing.
Bandai Namco proposed good definition to HDRIs that match scene - “True HDRI”. It not put any label about “Quality”.

And if capture don’t have a goal of exact matching of Backplates and HDRIs but captured HDRI must match scene colors and dynamic range even Theta X can be good. Plus 11K downscaled to 8K even allow to use such HDRIs for reflections or even for background.

I also made a quick and rough test for HDRI with xRite.
result HDRI match scene well, and lightings looks similar to captured moment.

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And that’s often what 3D artists want from HDRI :wink:

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Sorry for the Japanese article, we are starting a new web series.
We will be posting more detailed and up-to-date information about HDRI creation using the THETA Z1. The series will be updated approximately every month and will consist of at least 6 articles.

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Thanks for posting this. The article looks fine in English when using the Google Translate extension in Chrome.

Please let us know when more articles come out. :slight_smile:

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Craig, thank you for the huge amount of research you’ve done on this topic and for sharing! I don’t have the camera, but would like to convert the already stitched 360 jpgs from the Theta SC2 to exr backgrounds for my 3D rendering software (Enscape3D and Twinmotion). I’ve tried the PTGui Pro app and it doesn’t seem to recognize what kind of stitched file types they are. Any suggestions?

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Look into Luminance HDR Luminance HDR download | SourceForge.net

This tutorial is old, but shows how to create EXR with Photoshop

These are for images that are in equirectangular JPEG, like the images from the SC2

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The series has now reached its Part 5 installment.
Although a bit removed from THETA, Part 5 describes how to use an illuminance meter and Nuke to complement sunlight and correct colors.

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