Adobe has been hyping big changes to the HDR capabilities in CS5 and in my first spin around the new version, it looks like the hype is reality for the most part. I’m coming from CS3 Extended (skipped CS4) and while you could get a good result with the tonemapping operators in CS3, it wasn’t up to what other applications were offering even then. Adobe has upped its HDR game as we’ll see later on.
The biggest thing that struck me about the difference between HDR in CS3 vs. CS5 is speed. Merging a set of files to an HDR file in CS3 was very slow. The time to down convert from 32 to 16 bit seemed like an eternity in some cases. Not so with CS5. Merging a bracketed set is reasonably fast now on my computer and the time to drop from 32 to 16 bit is virtually nothing.
From the standpoint of tonemapping, the biggest change is the introduction of the HDR Toning panel. This offers far more control in the Local Adaptation screen than before. The other three options still exist – Exposure & Gamma, Highlight Compression and Equalize Histogram and those still work the same – but the changes to the Local Adaptation tonemapper are very much welcomed. I’ll come back to those in a bit.
Let’s start with what happens when you open an existing 32 bit .hdr file. If the file is tagged with an ICC profile different from your working space or is untagged, you’re now presented with a Missing Profile or Profile Mismatch dialogue box just as you would be with another image file type where that didn’t have a profile or where the profile was different from your PS working environment. This is a nice change. CS3 didn’t colour manage 32 bit files.
Once you’ve taken care of any colour management issues, the file opens and as in previous versions you can make several types of adjustments to the file before tonemapping it. View>32 Bit Preview Options gives you the Exposure and Gamma sliders to get started. From there, you can make H/S adjustments (as a note, it’d be nice if the Saturation slider changed to whatever colour you were working on rather than staying with red), Levels and a few others. As in previous versions, you can put these on a separate adjustment layer but there’s no point. As soon as you go into the tonemapping operations, the file has to be flattened so just make any changes on the Background Layer. Where layers do matter is if you want to ‘soft tonemap’ your HDR file. In this case, you make your 32 bit adjustments on adjustment layers then select Image>Mode>16 bit and you’ll be presented with an option to Merge or Don’t Merge. If you choose Merge, your layers are merged and the new HDR Toning screen comes up where you can tonemap the image before dropping to 16 bit. If you choose Don’t Merge, then the layers are retained and the image file is dropped to 16 bit without going through the HDR Toning. In this case, you can continue on making any additional adjustments, adding new adjustment layers to finish off the editing of the image. Soft tonemapping works if you want to be sure to keep a realistic look and not even have the possibility to venture into surreal-land at all. In this case, what I would do is group my 32 bit adjustment layers together and name them so I knew what they were if I come back to the image in the future and then group my 16 bit adjustment layers similarly.
Below are two versions of the same image that were ‘soft tonemapped’. The first is after dropping from 32 to 16 bit. As you can see, it’s still a little dark. The second is the final image after further adjustments in 16 bit mode.
Once you’ve made any pre-tonemapping adjustments, then the fun begins. For tonemapping you’ve got a couple options. As in earlier versions you can go to Image>Mode>16 bit and you’ll be presented with the new tonemapping panel. But!…. even before getting there, you can invoke the tonemapping panel by going to Image>Adjustments>HDR Toning. A screen capture of the new panel is below.
What you see here is the Local Adaptation option with all the new features. The image on screen is the one that’s going to be used throughout the test as the existing .hdr file, so you’ll be seeing it a lot over the next while. One aspect of HDR tonemapping that can be lacking in some software is fine control over the highlights. Not here. The Highlight slider in the Tone & Detail box gives very good control of highlights and does a really nice job of keeping what might be blown highlights (in the flowing water) under control. The Shadow slider gives similar fine control over the shadow areas of the image.
The preview of each slider as you move it is virtually instantaneous. No waiting, no hit and miss. Nearly instant feedback. Nice. The exception is the Curve at the bottom of the panel and you have to release your control point to see the effect. The Vibrance slider works like the Vibrance slider in ACR or Lightroom. It gently bumps up less saturated colours while leaving the more saturated colours alone. The Saturation slider, as in ACR and LR adjusts all colours equally. The Radius and Strength sliders impact how much of an effect the other adjustments will have, as you’d expect. The Detail slider is a microcontrast adjustment. Be careful with this one, a little goes a long way. It’s like s supercharged version of the Clarity slider in ACR and LR.
What’s cool about the new HDR Toning panel is you can invoke it as many times as you want. Just keep calling it up and making adjustments. As we’ll see below, this is really how you can go from mild to wild.
Once you’re done and want to drop the file to 16 bits, the same steps are used as previously. Go to Image>Mode>16 bit and the HDR Toning panel will be brought up again. If you don’t want to make any further changes, just select Exposure & Gamma from the top dropdown menu and click OK.
The result below is the ‘realistic’ version of the tonemapped HDR. The control you have now in PS for tonemapping makes getting a high quality, photorealistic result quite simple. As noted in the introductory article, no further adjustments have been done to this after it was tonemapped. From here, I’d do some additional colour adjustment, maybe a Curves adjustment and some sharpening.
The image below is the less than entirely realistic version. This went through two more iterations of HDR Toning before dropping down to 16 bit. So it’s quite easy to get an extreme result with the new tools as well.
Once you’ve got the image into a 16 bit space, if you really want to have some fun, you can apply the HDR Toning operator on the LDR file. It’s not available as an adjustment layer nor can you apply it as a Smart Filter by converting the file to a Smart Object. It’d be nice if layers could be maintained in the 32 bit file for tonemapping and it’d be nice if the tonemapping operator could be applied as a Smart Filter at least and as an adjustment layer would be better yet.
It seems pretty clear then that PS can deal with an HDR file merged in another program quite well, pretty easily generating both photorealistic and completely unrealistic results. Let’s move on to a merge of bracketed images done entirely within PS.
This is an 8 shot bracket at 1 stop intervals (+3 to -4). The files are NEF out of a Nikon D700 (12MP) shot on a tripod and the shutter fired with a cable release. The image below shows the 8 input files.
When loading the source files in the HDR Pro automation you’re presented with a checkbox to align files or not. Even though the shots were taken on a tripod with a cable release, I still check this to ensure proper alignment. This will slow down the merge a bit. There still is no manual alignment option as far as I can tell. Once the files are merged, the new Merge to HDR Pro dialogue opens up. Along the bottom are the input files and you can toggle then off and on to see the impact on the merged file. In the right side of the screen you can select to tonemap the file at this point by selecting 16 bit from the dropdown menu. Leaving it in 32 bit and clicking OK will take you out into the regular editing space where you can begin your pre-tonemap edits. Interestingly, with this bracket, the exposure values show in PS as -3 to +4 rather than -4 to +3. There’s no way to adjust the EV settings in PS either. It would also be a nice feature to be able to include additional exposures if the preview didn’t look as good as you wanted. In terms of speed, the merge of these 8 files took only a few minutes. I chose this scene in particular because of the extreme brightness in the large window on the left and wanted to see how each of the programs being reviewed would handle that. Once the preview is done and you click OK to go into the main edting screen, it takes less than a minute to open the file for editing.
The ‘realistic’ version went through two rounds of tonemapping. Keeping the windows from being blown out without affecting other parts of the image is difficult in this case. From here, I’d likely open one of the darker images in the sequence, place it as a layer on top of the background, make it a layer mask and use that to mask out parts of the window to bring back some detail. Or I might simply try using the Layer Blending options first to see if that would work since it’s a relatively concentrated area I’m trying to control with very similar tonal values. As you can see in the input images above, even in the darkest image, some of the windows on the left are white (overexposed) so inpart there just is no detail to recover. Removing some of the flare around the window would be good though. Additional colour adjustment, probably some selective dodging/burning and maybe some other tonal adjustments then sharpening are what would follow. At this point I’m less happy than with the previous image but the problems here can likely be overcome with some judicious editing and this type of problem isn’t uncommon, I’ve found, in situations similar to this where there is a large expanse of bright area.
The ‘mild to wild’ version also went through two rounds of tonemapping. Getting to this result was not a problem. And since we’re talking about a more extreme version here, I don’t much care about the windows.
Overall the HDR functionality of PS has been vastly improved. Both from the tools available and the speed. I could comfortably use CS5 to process and tonemap for a commercial assignment where quick turnaround is needed given the speed enhancements. There are a few tweaks that could make it even better as noted above but those are just nits. There’s no ‘Undo’ option in the tonemapping panel so if you make a change, don’t like it and want to go back to the previous setting, you have to remember what it was. The exception here is the Curve which does have a Reset option to bring it back to linear. The ability to ‘undo’ a change would be a plus.
In terms of the look/feel and ease of use, if you’re familiar with previous versions of PS, you’ll be quite comfortable with CS5. There are some cosmetic enhancements but generally the tools function as they have in the past. Don’t get me wrong, there are significant functional enhancements in CS5 as well, but I’m not going to get into those since the purpose here is to concentrate on HDR and the workflow for HDR.
Also new in CS5 are a variety of tonemapping presets. You can invoke these from the dropdown menu in the HDR Toning panel. Options range from photorealistic to very surrealistic, there are b&w options, high contrast, low contrast, etc. Try them if you want but personally, I prefer the control of tonemapping to my likes and needs. You can always adjust after applying a preset too.
Adobe has worked on the deghosting algorithms of the HDR functionality in CS5. I ran a set of 5 handheld images through (and I’ll do this with the other applications as well) CS5 HDR Pro that I knew had movement. It was a windy day and a tree in the scene was moving even capturing all 5 shots in less than a second with the D700 in high speed burst mode. The image below is a crop to show the ghosting in the branches.
By checking the ‘Remove ghosts’ box in the HDR preview screen, the program automatically chooses one of the exposures (the one outlined in green) as the one to use for the ghosted areas and removes everything else. It worksquite well. This is one of the best deghosting features I’ve seen so far. The result is below. There are still some artifacts and a bit of ghosting in one of the branches but overall, it’s quite good.
In terms of support, there is a terrific amount of information available from a variety of sources (some better than others) for Photoshop. There are books written by some very reputable and knowledgeable authors, the National Association of Photoshop Professionals (NAPP) has great information on their website. Doing a web search for any Photoshop topic will turn up a plethora of links. Adobe hosts a user forum on its website which can be very much hit and miss in terms of finding solutions. When it comes to technical support from Adobe, my personal experience has been that it’s pretty much non-existent. Response times are slow and rarely have I been able to get a resolution to a technical problem from Adobe. Great product, but less than stellar support.
If you read this and find that I’ve made a glaring (or even non-glaring) mistake in terms of the options and tools available in CS5, please let me know and I’ll make any necessary corrections.
Stay tuned for the next app. which will be Photomatix in a couple days.
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