Hdr file format ? Exr format

HDR give great lighting. I want to be able to create my own HDR images in photoshop. I downloaded the addon called easy hdri and they are loading in files with hdr file extension. How do I make that I can not save as hdr in photoshop.
(although I can watch hours of video about making a "high dynamic range image and save it as a tiff but that is not what I want.
This video shows how to make a hdri

but well its still not saving as hdr but it is saving as exr

I can make a exr file by using this plugin: Interesting - I found https://www.exr-io.com/

I can make the image look right in photoshop I just need a way to save the image as hdr so when I load it as a hdr blender will see it right.
So there is some confusion because a lot of hdr images I see are just weird shaped images that can be used to mimic a 3d world and I think that is different.
maybe that image above should be called a 3dworldimage not a hdr ???
So I see images that look like this above and people are calling it hdr but really its not
So with “Easy HDR” its not wanting to use my jpg images its wants to see a *.hdr as as shown on this page below:

At this point I am hoping someone will clear up the difference between a warped image like above and what photoshop is refering to as a image that is 3 images combined with different exposures. So I can make a HDR by putting my camera on a tripod and taking 3 shots one getting all the detail in the shadows and one that shows all the detail in the highlights and then one more that captures great color and midtones. So that would be a HDR image created from those 3
So a few pointed questions: So why is Easy HDR insisting that I have a hdr file extension ? and why did the first video I posted about making HDR in blender being saved as exr ? will blender use a exr as a “3dworld image”
Right now I have a mind full of mixed up mush and hope someone might tell me a thing or two to straiten me out.
If I use nodes can I make blender see any tiff or jpg or png as a 3dworldimage ? Did hdri just kinda get thrown together with 3dworldimages because 3dworldimages should be hdri images ?

basicly my goal is to be able to use a jpg image of my own choice to create great lighting on a subject. I also want to be able to create my own 3D worlds if I want to. But a lot of HDR is thrown in this works and its confusing me.

I don’t know a lot of stuff but… HDRI stands for High Dynamic Range Image. What that means to me is that there is more information than in a jpeg for your lighting. I think EXR’s may store that much information but I don’t know without reading a bunch of stuff. I did see this (https://www.creativeshrimp.com/hdr-lighting-in-blender-part-6.html) after searching for “hdri with camera blender” on duckduckgo.

The way that HDRI images are created normally as far as I know is with multiple exposures with a camera. If you want to use your camera to do it you will likely need some equipment and a camera that will automatically take multiple exposures at once. I don’t think that this is all that uncommon.

This may not answer your question but it may help. Also there are many free HDRI’s online that you can use I think. As far as creating an equirectangular image ( as I think that’s what that image is called ) Don’t know, probably a plugin, somewhere. I think though that it could be both equirectangular and HDRI. Equirectangular is what blender calls it in the environment texture.

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OK now that I know "equirectangular image " this is helpful that word this helps
so yes I think people are using Equirectangular images and they may as well be hdri.
I guess the hdri and Equirectangular have become convoluted

.hdr and .exr are both 32bit formats. (images wich stores information with floating numbers wich can eceed 1.o (255). ) You should be able to load and save them in photoshop, saving out a 8bit (jpg) as an 32bit image for lighting won’t make a difference (except for the bigger filesize).
(But you can also use jpgs for lighting to a certain extend. )

The 8bit images wich are called hdr, are tonemapped images wich were original hdr and then squeezed the image lighting information in the 8bit range.

So what program saves hdr ? Photoshop ? Do I need a pluggin to do that or ?

phtoshop does support both exr and hdr
Kirta does allow exr
Affinity Photo allows hdr and exr
blender supports hdr and exr
there is no functional difference between exr and hdr if you just want to use it for lighting

…there is also 32bit tiff but that opens another can of worms

Unless I am overlooking it I can not find a save as to HDR so I must have to find a pluggin. But I do find exr pluggin — so maybe that is all I need. Does photoshop have a pluggin that makes it save to HDR or does my newest version omit it ?

HDR is a woeful format for encoding scene radiometry due to inefficient quantisation. Stick to EXR where you can.


Bit depth alone is not the issue. It’s the nature of the encoding.

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yes if possible you should use exr, due to file size, although there are several applications wich only supports a lower version of exr than blender provides (cs 5.5 and below) or do not support exr togehther. Also tiff (wich has even a bigger file size) is still a use´full format. (Latest example I’ve encountered is focus stacking hdris in affinity photo). A reason why the op has problems might be that he has an older photoshop (non extended) version wich do not support 32bit at all.

More equivocated even than HDRIs with equirectangular images is HDRIs with tonemapped images. Often you will see an image that claims to be HDR, which is really a tonemapped image.

This is to say that the photographer took the photo at a variety of different exposures, and then used an editor (such as GIMP) to selectively bring out details in both the shadows and the highlights, which could not have been done with a single shot straight out of the camera.

In this way, the photographer has captured a “high dynamic range” and accordingly labels their finished work as an “HDR”, but being a jpeg or png, it will not function as an HDRI for lighting purposes as it lacks the 32-bit depth of .hdr or .exr images.

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The term “HDR” refers to the image data itself: it has a “higher dynamic range” than an actual photo could ever capture. (In a smart-phone, it captures three exposures and combines them.) In this way it comes closer – but, not all the way – to what the very-amazing human eye (and visual cortex) can perceive when looking at reality.

“EXR” is a data file format which captures the image data as “a great big file of floating-point numbers.” It was originally developed by Industrial Light & Magic. Its purpose is to capture the raw numeric data produced by a renderer, exactly, and “file size doesn’t matter.” (Loss-less compression is used.) It stores one frame per file. Then the Blender Foundation(!) came along with the “MultiLayer” extension, which stores multiple “layers” of data in just one file – very convenient, and so very promptly adopted by everyone in the industry. EXR files are intended to be intermediate data files for use in a larger workflow, and in that role they work very well. They’re most appropriate for storing HDR image data, because “what data goes in, is exactly what comes out, no matter what it is.”

“Image files,” such as PNG and JPG, and “movie files” like MOV, are designed for the efficient final-display of images on what might be “cheaply-made equiplment with not much storage space.” The data has been compressed to save space, and “lossy” techniques are used. The images have been pre-processed in various ways so that the [cheap …] hardware doesn’t have to do it. They are therefore not appropriate for use within your workflows: you should use them only generate all of the “deliverable” files that you need, individually, in the very last step, takeing each one from the same EXR-based “master.” (Do not generate one from the other, because garbage adds up quickly.)

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HDR is an acronym, yes of course, but it’s also a file type. I found this post because I have the same question/issue. I can get a .hdr file and open it in Photoshop, but after I make a few modifications (like changing out the colors on one side of the image to something that fits my scene better) but then it won’t allow me to resave it in the original .hdr file format. I’d love to know how to get Photoshop to do this, or know what software lets you open .hdr files, modify them, and then resave them in their original .hdr file format.

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Photoshop saves .hdr files just fine. Go to File>Save As and select RADIANCE(*.HDR,*RGBE.*XYZE) as the file type.

If you make changes to the file, make sure you don’t change the bit depth. Go to Image>Mode and make sure that “32 Bits/Channel” is still checked.

So what is the file extension for this multilayer file format ?

I have found to be the fastest to use Gimp - just open OpenExr and res save it as Radiance (.hdr).
I even created blog entry with this simple tip here