noise problem in LR with HDR home interior shots

[zulu42]

I have this recurring problem with LR. It often creates these noisy areas, especially with interior shots and high contrast window areas.

Is there something I am doing wrong in the process? I use 3 to 5 exposures usually in one stop increments. Then LR - HDR merge with auto tone, auto align, and medium de ghosting.

Any help would be most appreciated.

 

[Braineack]

never been a fan of LR's HD Merge.

the above suggests they were using a poorly exposed portion of that area and then add exposure to that...


i might suggest to pick the number of exposures and stops that is absolutely necessary to get the full dynamic range, and not just arbitrarily. This is where studying your histograms will come into play.

 

[tirediron]

...i might suggest to pick the number of exposures and stops that is absolutely necessary to get the full dynamic range, and not just arbitrarily. This is where studying your histograms will come into play.

This is the key point; you've got much more than three stops of dynamic range in that image, and any time you up shadow exposure, you're going to get noise, and the more you increase exposure, the more noise you get. Ideally, this should be done using lighting to correct for exposure, but if you want to use HDR, then you'll need to use an appropriate number of exposures. A hand-held light meter (ideally a spot meter) will make this task much easier.

 

[zulu42]

Thanks for the replies!

the above suggests they were using a poorly exposed portion of that area and then add exposure to that...
.

Looks like added exposure noise... but, it's the window. The exposures on the window ranged from completely blown to a good exposure. Why would LR be adding exposure to the highlight areas?

 

[zulu42]

This is the key point; you've got much more than three stops of dynamic range in that image, and any time you up shadow exposure, you're going to get noise, and the more you increase exposure, the more noise you get. Ideally, this should be done using lighting to correct for exposure, but if you want to use HDR, then you'll need to use an appropriate number of exposures. A hand-held light meter (ideally a spot meter) will make this task much easier.

Way more than 3 stops of range, yes, but most of that DR is within the DR of my camera. I should really only need one exposure for the room and one exposure for the windows and lights, or is my thinking flawed there?

And the shadows don't have noise. The brightest part of the frame got the noise... weird.

 

[tirediron]

Are we looking at two different things perhaps?

In your image, I've bounded the areas where I see the most prominent noise with red lines:

Those are definitely in the shadow area of the image, the header over the window, the mullion, etc. Since the key light (the sun) is outside, it stands to reason that these areas which are only being illuminated with reflected light will be darker than those receiving direct illumination through the window. With respect to your question on dynamic range: first, we don't really know how LR (or any software) is going to treat a particular area; it might pull/push more than we think it should, or less.

Second, when we talk about the dynamic range of a camera, we're talking about its ability to record recognizable detail across a range of 'X' stops, NOT the ability to change that exposure. Regardless of what camera you have, any time you increase exposure in post, you're going to impart noise. That's just the way it works. The greater the change, the greater the amount of noise... based on the lighting in the room, I would guess that the shadow areas i have marked could easily have been pulled three stops.

If I were doing this as an HDR, I would probably go no more than one stop per image, and I would invest in some better software; LR does the job, but it's a bit crude in many ways. Still, the best way to do this would by adding light to the interior. One exposure and done!

 

[zulu42]

@tirediron , you're absolutely right. I even went back and looked at the original exposures, and I didn't expose those shadows bright enough even at the brightest exposure. Need to take more care with the histograms when shooting.

Do you think you would light this room with one diffused strobe? I wonder if it is more work to bracket and HDR, or to bring one or more lights.

Thanks Very much for the help!!!!

 

[Light Guru]

With HDR it’s best to measure your shadows and measure your highlights before you take your photos. Then ensure that your brackets include your highlights and shadows.


Sent from my iPhone using Tapatalk

 

[tirediron]

@tirediron , you're absolutely right. I even went back and looked at the original exposures, and I didn't expose those shadows bright enough even at the brightest exposure. Need to take more care with the histograms when shooting.

Do you think you would light this room with one diffused strobe? I wonder if it is more work to bracket and HDR, or to bring one or more lights.

Thanks Very much for the help!!!!

I would probably use two or three. One either side of camera to cross light (light camera left illuminates room corner right, & vice-versa) and possibly drop a small light behind the end of the dresser to provide some fill on the main wall image left. I tend to favour multiple small lights vice one large one, but you could do it with a single light if you placed it carefully; remember: the idea is that the viewer doesn't know that you've used supplemental lighting.

 

[zulu42]

I would probably use two or three. One either side of camera to cross light (light camera left illuminates room corner right, & vice-versa) and possibly drop a small light behind the end of the dresser to provide some fill on the main wall image left. I tend to favour multiple small lights vice one large one, but you could do it with a single light if you placed it carefully; remember: the idea is that the viewer doesn't know that you've used supplemental lighting.

Sounds quite a bit like work! I think I will fumble around with HDR.
When I got better exposures, the noise is not present:

 

[Compaq]

I recommend using luminosity masks. You will get a very natural exposure blend, and no added noise. If you don't know what luminosity masks, check out the following video by Jimmy McIntyre. I really recommend his software Raya Pro 3, a plug-in for Adobe Photoshop.

 

[The Barbarian]

Even with a perfect set of exposure, I usually denoise them. Just works better for me.