Indoor HDR self made doen't give the same illumination

insensibile

I'm trying to create an indoor HDR that gives the same light I have when using the emissive lights in the scene but I'm not able to have a good result (I use only GIMP, Darktalbe and Raw Therapee).
I tried several methods:

1, single image PNG format

2. single image converted into HDR format in GIMP with no editing

3. single image with two duplicated layers edited with NIK efex 2 in GIMP and saved as HDR

4. Three different rendering with shutter speed set to 30, 128 and 300 than packed and converted to HDR

5. Three different rendering with shutter speed set to 30, 128 and 300.  Edited in GIMP with NIk efex 2 than packed and converted to HDR

6. Three different rendering with shutter speed set to 30, 128 and 300.  Color levels and curves edited in GIMP than packed and converted to HDR

None of these methods gave me the same light effect I have in the original scene even changing the environment map and intensity.
Can someone suggest me a more effective method?

f7eer

I'm not an expert in this and I have never done it before, but my understanding of creating an HDR image from a normal camera is that the n exposures (in your case, 3) are made with the camera, producing n images of differing brightness. These are then combined to produce an HDR image with a vastly expanded physical brightness range. Also, the scene in your photos must include one or more light sources, or at the very least, rays of sunlight or moonlight illuminating an otherwise non illuminated room, which becomes a light source.

The conversion to HDR must be able to take multiple exposure photos as input, to produce one HDR image.

So, it seems like you are doing a rendering step (4), instead of a multiple exposure step, and that is why your scene doesn't have enough light or it's too even, which is what I assume the main problem is, although you never state what the problem is.

Richard Haseltine

An HDR light is a full sphere surrounding the scene - it sounds as if you are making an HDR version of the render from only a single camera, so when you use that to light the scene it is going to be very different (try emabling Draw Dome and rendering).

Kevin Sanderson

This step by step seems pretty effective.

insensibile

Kevin Sanderson said:

This step by step seems pretty effective.

I have already watched this wideo (this is why I use 30, 128 and 500 values on shutter stop) but I don't use Photoshop and GIMP doesn't have the HDR autocomposer.

insensibile

f7eer said:

I'm not an expert in this and I have never done it before, but my understanding of creating an HDR image from a normal camera is that the n exposures (in your case, 3) are made with the camera, producing n images of differing brightness. These are then combined to produce an HDR image with a vastly expanded physical brightness range. Also, the scene in your photos must include one or more light sources, or at the very least, rays of sunlight or moonlight illuminating an otherwise non illuminated room, which becomes a light source.

The conversion to HDR must be able to take multiple exposure photos as input, to produce one HDR image.

So, it seems like you are doing a rendering step (4), instead of a multiple exposure step, and that is why your scene doesn't have enough light or it's too even, which is what I assume the main problem is, although you never state what the problem is.

In the 6th method I used 3 different exposure step and I tried many combinations changing curves and levels of the colors and lights.  The problem is not the lack of illumination but the opposite.  Every combination I tried gave me too much illumination in the scene but if I decrease intensity and map values the HDR loses color brightness and vividness.

insensibile

Richard Haseltine said:

An HDR light is a full sphere surrounding the scene - it sounds as if you are making an HDR version of the render from only a single camera, so when you use that to light the scene it is going to be very different (try emabling Draw Dome and rendering).

I use a single camera with spherical lens for 3 rendering with 3 different exposures.  I use the HDR as static background for an animation that requires a static camera. So the Draw Dome is set to on.  The animation is quite heavy so I need the HDR. 

insensibile

The only solution I found at the moment was to ask a friend to merge the 3 rendering for me in Photoshop usind the "Merge to HDR".  The result is excellent and the illumination is the right one.  But I will not stop searching a solution with GIMP.  There must be a way to have the same result with it!

marble

Removed

j cade

Use picturenaut to convert your 3 images to an hdr.

Its free and thats what its designed to do and does well

 

 

insensibile

j cade said:

Use picturenaut to convert your 3 images to an hdr.

Its free and thats what its designed to do and does well

 

 

I tried it but it doesn't work well with png format (like Luminance HDR, another free one) and using jpg format the final result is far miles away from the perfect job done by Photoshop. Thank you anyway for the suggestion.