Photomatix & Arch Photography

[Claudio Branch]

Anyone here using Photomatix to create hdr's for architectural photography?

[cadmunkey]

Hi Claudio, I looked into using it recently - unfortunately the demo version only allows you to combine images of 2 exposure levels so its pretty limited and doesnt let you use it to its full potential. However there are some really good examples on their website. I do know of a couple of people who use it regularly and love it.

[Jeff Mottle]

I've never really understood the facination with HDR photographs. It makes sense when they are generated synthetically to use as a light source, but I have seen very few HDR photos that do not look really over processed and ugly IMHO. Even the examples on the Photomatix website don't look that good.

[Claudio Branch]

 

Hi Claudio, I looked into using it recently - unfortunately the demo version only allows you to combine images of 2 exposure levels so its pretty limited and doesnt let you use it to its full potential.

 

 

Are you sure about this? I had a demo version that was combining up to 10 exposures, but it did leave a watermark.

[Claudio Branch]

 

I've never really understood the facination with HDR photographs...

 

...I have seen very few HDR photos that do not look really over processed and ugly IMHO.

 

 

For me, the intrigue is in using only available light. There is also a real element of discovery about how light accumulates and imbues the environment.

 

On the second point, I wholly agree, but I would qualify my remark as well. You just have to know where to look...

[shaneis]

For me, the intrigue is in using only available light. There is also a real element of discovery about how light accumulates and imbues the environment.

 

On the second point, I wholly agree, but I would qualify my remark as well. You just have to know where to look...

 

You've probably seen this one of NYC -

 

His daytime HDRI's tend to fall into the category that Jeff mentioned, but he's quite good at emulating how we see light at night with the naked eye... and he uses Photomatix with only a few brackets.

 

Sean McHugh http://www.cambridgeincolour.com/cambridge-gallery.htm also manages some good ones, those being the night shots again. Photoshop for his HDRI's.

 

Interesting that the better HDRI's out there are effectively very low light shots whereas the daylight versions always look over done. Something akin to the Impressionist's use of pastel compared to the '80's use of pastel .

[Crazy Homeless Guy]

Funny, I was just looking at Photomatix last night as an option for better control over exposure in renderings.

[kainoa]

I agree that some people take HDR a little too far. But I do see some pretty neat stuff from time to time. IMO it's akin to a PS filter, you can get carried away and get something very cheesy, but they do have their uses in the right situations.

 

I personally use Photomatix/HDR for my arch photography as an alternative to having pro lighting gear. Like needing to shoot an interiors space and getting the exterior view properly exposed as well.

 

For instance, my firm was submitting a recently completed hotel renovation here in Hawaii for an award. We flew out a well-known ($) photographer to shoot the final design for use in our submission. He took 2 weeks and shot what 'he' thought were 'the' shots. While they were all great there were some additional photos we thought we needed for our submission. The deadline was near and I basically needed to get the additional 6 or 7 shots in one afternoon. I only have a Canon 40D and a Sigma 10-20mm lens. No external flashes and not much time.

 

Attached are just a couple of the shots i took. HDR was helpful because in some cases it was nearly impossible to get everything properly exposed w/o pro lighting. Either the sky would have been washed out, or the interior/building too dark. Tweaking a single RAW file might have been ok for some, but would not have been as successful IMO.

[cadmunkey]

Personally I think these look good, thanks for sharing Jason (Kainoa).

[Ernest Burden III]

Funny, I was just looking at Photomatix last night as an option for better control over exposure in renderings.

 

Some of the HDR photos I've seen look like a strongly applied HighPass filter. The daytime shots often look over-processed. The night-time shots are more appealing. This suggests the technique can be transformative. That's great, as long as that's what you want. Otherwise, it can detract from the 'realism' sought in a photo.

 

The idea to use the HDR techniques for renderings is interesting. I had wondered about it myself, but wasn't aware of this software. What it may do in an automatic way is what I do by hand for most renderings. I call it local contrast, as the idea is to isolate objects or areas of a picture and adjust its contrast (dynamic range) individually. You make that item read better as a unit but can cost the picture as a whole some of its unity.

 

I would love to see some tests posted with raw renders and the results when using this HDR technique meant for photos.

[Claudio Branch]

Shane, thanks for those links...a few of those images are top notch.

 

Jason, I think your strategy paid off!

 

HDR can be used for it's own sake or strategically when time and money is an issue. There is alot of bad hdr work out there and there is also bad V-Ray work, bad watercolor work, bad Photoshop work.

 

In the end it as just another tool to be wielded by an artist. Sometimes the artist needs to show restraint and sometimes he must bring it!

 

http://www.flickr.com/photos/claudiobranch/

[Claudio Branch]

 

I would love to see some tests posted with raw renders and the results when using this HDR technique meant for photos.

 

 

The ideal way to do this would probably be to use V-Ray's Physical Camera to create the range of exposures and then import the exposure sequence into Photomatix. However, I believe that Photomatix requires RAW (.NEF) files for processing purposes.

 

I have yet to use the Physical Camera on a project. Another thing I need to learn...

[Stephen Thomas]

The ideal way to do this would probably be to use V-Ray's Physical Camera to create the range of exposures and then import the exposure sequence into Photomatix. However, I believe that Photomatix requires RAW (.NEF) files for processing purposes.

 

I have yet to use the Physical Camera on a project. Another thing I need to learn...

Photomatix can load HDR files as well as RAW images. Since Max/VRay already outputs 32-bit images I don't think there would be any benefit in saving out a series of exposures then merging. That way you can bypass that step and go straight to the tonemapping. The only reason you would use more than one image with photos is if the camera cannot capture the full dynamic range of the scene, or if you really want to bring out more of the shadow or highlight detail. Max will capture the whole range in one shot though so just go with one HDR output.

 

One thing that always annoys me with some photographers using Photomatix is when they save out loads of exposures from a single RAW image and bring them into Photomatix as if that somehow magically creates more of a dynamic range than the original RAW file. Madness.

 

Also, there are many tricks that most of us use everyday to compress the dynamic range in our scenes even before hitting render. Like being able to control the exposure of the background image independently from the scene lighting for example, or override materials. I think that there are enough ways to achieve a balanced exposure within max itself that there really isn't the same need to do it in post as there might be in the photographic medium.

[SandmanNinja]

I use PhotoMatrix, but mainly for dusk/night photography or for situations where a flash cannot/should not be used (interior of a museum with old paintings, for instance).

 

I've always had 'errie' photos when I take exteriors - the clouds keep moving and it makes kind of a spooky or unnatural image.

 

Just had an idea - can photoshop stitch a sequence of HDR images from PhotoMatrix?

[Stephen Thomas]

I use PhotoMatrix, but mainly for dusk/night photography or for situations where a flash cannot/should not be used (interior of a museum with old paintings, for instance).

 

I've always had 'errie' photos when I take exteriors - the clouds keep moving and it makes kind of a spooky or unnatural image.

 

Just had an idea - can photoshop stitch a sequence of HDR images from PhotoMatrix?

I can never manage to avoid the ghosting problems with clouds or trees either.

 

Regarding your stitching question it depends on what part of the process you're talking about since Photomatix is a two-step thing. Step one is merging the bracketed exposures to create an HDR file and then step two is tonemapping the HDR image to compress the dynamic range down to an 8-bit file in whatever way suits your taste.

 

If you then bring stitching a panorama into the equation then you have two options. Photoshop cannot stitch HDRs as far as I know so you would need to merge the exposures for each image and do the tonemapping in Photomatix, repeating this for each shot, then stitch the resulting images in Photoshop. Or you could use the new version of Autodesk Stitcher which allows you to bring in bracketed exposures of each image and then stitches them as an HDR. You would then need to follow this by doing the tonemapping in Photomatix on the resulting HDR panorama.

 

Stitcher is a great program and gives you much more control and does a better job of balancing the exposure across the image than the photomerge tool in Photoshop, well worth checking out if you're into panos.

[Claudio Branch]

 

I can never manage to avoid the ghosting problems with clouds or trees either.

 

 

Any "ghosting" due to long exposure times is going to be inevitable. You simply have to wait for the best conditions. It can also be minimized if your camera has auto exposure bracketing.

 

Another type of "ghosting" that you may notice on hdr photos is called "halo" and this usually occurs as an artifact of tone-mapping. Halos will occur when using Photomatix's Details Enhancer method with the Light Smoothing set too low. This happens very quickly with images that already have alot of contrast, especially in the areas of the sky.

[shaneis]

Any "ghosting" due to long exposure times is going to be inevitable. You simply have to wait for the best conditions. It can also be minimized if your camera has auto exposure bracketing.

 

Just adding to the bracketing solution, use the bracketing function in combination with the continuous shutter function and you'll have all of your exposures done within a couple of seconds. It'll depend on your camera of course, a D3 can take 9 bracketed exposures with at 9fps. My D90 will do 3 bracketed exposures at 4.5fps. Use a tripod and a remote as well.

[Stephen Thomas]

Yeah, more the movement problem I was referring to. I tend to shoot RAW most of the time and on my camera that disables the autobracketing function. Probably better just sticking with jpegs next time I give it a go.

 

Incidentally, can anyone tell me the difference between the exposure blending and the tonemapping functions in Photomatix. Is it just that the tonemapping gives you more sliders/control or is there fundamentally something different going on in terms of how the exposures are put together?

[Claudio Branch]

Just adding to the bracketing solution, use the bracketing function in combination with the continuous shutter function and you'll have all of your exposures done within a couple of seconds. It'll depend on your camera of course, a D3 can take 9 bracketed exposures with at 9fps. My D90 will do 3 bracketed exposures at 4.5fps. Use a tripod and a remote as well.

 

I have a D40 without exposure bracketing! So, for all of my hdr's I have to use a tripod and manually change the shutter speed.

 

I would definately like to upgrade and pehaps throw in a nice telephoto lens as well...

[Stephen Thomas]

I have a D40 without exposure bracketing! So, for all of my hdr's I have to use a tripod and manually change the shutter speed.

 

I would definately like to upgrade and pehaps throw in a nice telephoto lens as well...

Would love to upgrade as well. At the moment I'm just using a Fuji s9600, which isn't an SLR but has a lot of the same features. Not sure what I'd like to go for yet but it's all academic since I don't have the money anyway!

[Claudio Branch]

 

Incidentally, can anyone tell me the difference between the exposure blending and the tonemapping functions in Photomatix. Is it just that the tonemapping gives you more sliders/control or is there fundamentally something different going on in terms of how the exposures are put together?

 

Stef, this is straight out of the Photomatix FAQ's:

 

What are the differences between Exposure Blending and HDR/Tonemapping? Both processes start from the same source files: differently exposed Low Dynamic Range (LDR) images. And both attempt to produce as final result an LDR image that shows tonal details of the entire dynamic range captured by the different exposures. The differences are in the process itself. Exposure Blending consists in combining the differently exposed images in such a way that highlight details are taken from the underexposed photos and shadows details from the overexposed ones. Since the bit-depth does not change throughout this process, the basis of Exposure Blending algorithms is a type of weighted average of the source images. One of the advantage or Exposure Blending is that it is easy to understand and you can see what you are doing. Also, it is rather familiar to photographers who are used to doing this process manually in image editing applications. Another advantage of Exposure Blending is that it reduces noise. HDR Tone Mapping is composed of two steps. The first step creates an HDR image from differently exposed photos. This HDR image can not be displayed correctly on a Low Dynamic Range monitor, which is why a second step called Tone Mapping is necessary. Tone Mapping consists in scaling each pixel of the HDR image, so that details in highlights and shadows show correctly on monitors and prints (those details are available in the HDR image but not directly visible in both highlights and shadows because of the low dynamic range of the display). Tone Mapping algorithms vary from a simple gamma curve (which is often what cameras are doing when converting 12-bit RAW data to 8-bit JPEGs) to more complex operators commonly divided into two categories: ·Global operators: mapping depends on the pixels' intensity and global image characteristics, but not on spatial location·Local operators: mapping takes into account the pixels' surroundings (in addition to intensity and image characteristics). The main advantage of global operators is fast processing. Local operators require longer processing times but they are better at producing a "good-looking" photograph (the human eye adapts to contrast locally). In Photomatix Pro, the Tone Mapping method "Details Enhancer" belongs to the category of local operators and the method "Tone Compressor" to the category of global operators. The pros and cons of Exposure Blending vs Tone Mapping in Photomatix Pro are detailed under the section below.

[Stephen Thomas]

So basically RTFM then?

 

Cheers for that Claudio.

[Claudio Branch]

Yeah pretty much I suppose!

[Claudio Branch]

Also, there are many tricks that most of us use everyday to compress the dynamic range in our scenes even before hitting render. Like being able to control the exposure of the background image independently from the scene lighting for example, or override materials. I think that there are enough ways to achieve a balanced exposure within max itself that there really isn't the same need to do it in post as there might be in the photographic medium.

 

I pretty much have to agree with all of this.

 

But, perhaps still worth pursuing if not for technical merits, but in the spirit of experimentation?

[Stephen Thomas]

Oh yeah, definitely. Was just meaning that most of us probably use a similar process already without really being aware of it.