Merge to 32 bit - HDR technique comparisons

Merge to 32 bit – HDR technique comparisons

HDR is an often discussed and debated subject in photography circles. There’s much talk about “bad” HDR, or a whether or not one should even do it in the first place. I think a lot of that stems from what I’d consider to be overdone, over-processed versions.


Depending on the software used to make your tone-mapped HDR images you may be given an option to view and/or save a 32-bit version. Prior to Lightroom 4 we there wasn’t really much we could do with such a file so most photographers never bothered saving it. Now that LR4 and PS can handle a 32bit file it has opened up a whole new set of options for HDR, one that is a lot simpler, more photo realistic, and many would venture to say – better.

The problem with most overdone HDR images is that they are often:

  • too overly saturated, way past surreal into unpleasant looking by many accounts
  • too flat, the blacks are grey and the highlights are grey and muddy looking
  • too far into the realm of “surreal” or “artistic” where the shadows are now brighter than some of the highlights, and the highlights are darker than some of the shadows. It seems unnatural and many people reject it because their brain’s can’t even register it.
NOTE this is an example of what NOT to do, please do NOT make HDR that looks like this.

Please do NOT make HDR that looks like this!


  • perhaps you’ve tried HDR and been unhappy with the results
  • maybe you vowed never to touch it for fear of producing something that falls into one of the above areas. If that is the case I urge you do take a second look and see if this is more to your tastes.
  • the process baffles you and you just want a good final result without having to learn yet another software

Photomatix Pro has been one of the front runners for HDR tone-mapping software since its creation. Now they offer a new plugin for using that 32-bit image. I’m not going to get into the step by step how to use shoot your bracketed images or use this plugin (they already have that on their site here), rather a comparison of a three different methods of making HDR images and the resulting images.


Okay in a nutshell, this is how the plugin works.

  1. select your bracketed images in LR or PS
  2. launch the 32-bit plug in (and select a couple options) and it does its thing in the background
  3. take the resulting 32-bit image and finish it in LR or PS
Screen shot 2013-06-27 at 8.06.37 PM

Select bracketed images

Screen shot 2013-06-27 at 8.07.20 PM

Launch the Merge to 32-bit HDR plugin

Screen shot 2013-06-27 at 8.41.07 PM

And away it goes! How easy right?

That’s it!  No sliders to play with, no presets, no way to muck it up – the software just merges them together into one massive file with a whole lot of exposure data. Then you work the magic on it in Lightroom or Photoshop (or your favorite image editor) to lighten where you want, and darken where you want – with no loss of image quality or detail.


Below you see the four bracketed images I’m using for this example. Notice that the darkest image shows lots of detail in the white wall on the right of the doorway, and the lightest image has tons of detail on the ceiling inside the building. I use the histogram and shoot in manual to make sure I capture enough range and generally bracket 2 tops apart (these are about 1 and 2/3rds apart as it was enough to get the range I needed) – notice I only ever adjust the shutter speed, keep my ISO low and use a tripod whenever possible.


Bracketed images shot in Manual mode on tripod

Below you see the 32-bit image as it first appears in Lightroom. It looks pretty contrasty (almost exactly like the second image above) but unlike using just a single image there is plenty of detail in ALL areas of this image, you just have to manipulate it out a bit!


Merge 32-bit image before Lightroom processing.

Here is the final version after doing some Lightroom magic.  I’ve used several of the sliders pulled to the max (see screen shot of my Basic panel below), as well as some Graduated filters on the edges (see screen shot below), a post-crop vignette, and several adjustment brushes to lighten and darken areas I wanted to control. Notice the white wall on the left is quite dark now, almost grey – however the highlights inside the house are still bright white. If you just darken all the highlights you end up with a flat, muddy looking mess. I’ve also darkened the wall outside intentionally to draw your eye inwards towards the brighter areas and the chair. If the wall was still pure white it would scream and draw your attention.  Notice how the image still has dark areas, light areas, and a good contrast range. All I’ve done is control the tonal values to retain detail where I wanted.


Final image after Lightroom adjustments

Basic panel adjustments in LR

Basic panel adjustments in LR

Gradient filters used to darken the edges of the doorway

Gradient filters used to darken the edges of the doorway

Now have a look at another version of the same bracketed image set, but this time created using the full Photomatix Pro software and LR adjustments afterwards.  It’s a much grungier look, which some people dislike. Personally I like this look and it’s not going too far for my tastes. There’s still pure black, and pure white in the image and it has good contrast – the tones have just been adjusted in a different way.

HDR done by tonemapping in Photomatix Pro

HDR done by tonemapping in Photomatix Pro

One more version, also tone mapped in Photomatix then split toned in LR

One more version, also tone mapped in Photomatix then split toned in LR


Let’s look at two more images as examples. I’ve used three different processes to get the final results in each set:

  • using just Lightroom adjustments
  • using the regular Photomatix Pro tone-mapping process
  • using the merge to 32bit method

Can you guess which is which in each trio?  No fair peeking at the file names!   Look over the three versions of each scene and tell me in the comments below which was done with what process.  How can be first to get it all right?  GO!








To revisit my original question – is merge to 32-bit the answer for better HDR? I think that’s probably still up for debate. It does however allow you to create a much more photo realistic result with relatively few easy steps, and less hassle. So if you fall into one of the categories at the top of the article I’d suggest you give it a try especially if you want to do tone control but not alter the look of the image beyond that of reality.

As always, give me your thoughts and opinions. There’s always many different options and opinions and no one solution is right for everyone.

Read more from our Tips & Tutorials category

Darlene Hildebrandt is an educator who teaches aspiring amateurs and hobbyists how to improve their skills through articles on her site Digital Photo Mentor, online photography classes, and travel tours to exotic places like Peru (Aug 31st - Sept 13th, 2019), Thailand, and India (Oct 28th - Nov 11th, 2019). To help you at whatever level you're at she has two email mini-courses. Sign up for her free beginner OR portrait photography email mini-course here. Or get both, no charge!

Some Older Comments

  • Darlene August 1, 2013 04:00 pm

    Very nicely done! Great detail in all areas, not overdone. Good job.

  • Arthur Bravo August 1, 2013 12:38 am

    By the way, I was totally busted in the last set of photos haha.

  • Arthur Bravo August 1, 2013 12:33 am

    Thanks a lot for the article, find it pretty useful. I've tried both methods - photomatix and 32bit in photoshop - and I find a lot more useful the 32bit one. I didn't knew that you can merge HDR in lightroom without going into photoshop, think it's going to be useful in the future.

    I share to you an 32 bit HDR I did a time ago, please let me know what do you think about it.


  • Darlene Hildebrandt July 18, 2013 09:54 am

    Steve, Ivan, Anthony - first set right.

    hah, stumped everyone on the second set!

  • Darlene Hildebrandt July 18, 2013 09:50 am

    @stefan - no I don't think so but I haven't tried it using PS's 32 bit option. Perhaps do a trial on the Photomatix plugin and compare for us if you like?

    @captain - nice to see you hear, thanks for commenting and sharing this article.

    The correct answers are:

    Car by fence in order: LR - 32bit - Photomatix

    Japanese temple (which is in Hawaii BTW) in order: 32bit - LR - Photomatix

    who got it right?

  • Stefan July 13, 2013 07:59 pm

    Hi Captain Photo,

    Thanks for the explanation, that of course makes sense. I was just wondering if there was any technical difference.



  • Duane July 10, 2013 12:39 am

    at least one of the finest Merge to 32 bit & I located up to date

  • Captain Photo July 9, 2013 05:46 pm

    Hi Stefan! For me, the difference amounts to a couple of things. These are of particular importance to beginners to HDR.

    First, the 32 bit HDR method is cheaper. If I don't have to buy Photoshop, I save a bundle of money.

    Second, it's easier. No steep learning curve of Photoshop so this brings HDR to a more receivable level for millions more photographers.
    There are actually three things;

    It's Faster. The files start in Lightroom and never leave so I can immediately apply global and local adjustments. Anybody can get a great HDR in less than 5 minutes.

    And when you want to spend more than 5 minutes, that's when it really gets fun.

    There's nothing wrong with Photoshop. If you have it, know how to use it, love it, and make fabulous photos with it, why leave it? If you're NOT one of those, then the 32 bit method makes perfect sense as the way to get started in HDR. You can always buy Photoshop later, if you still think it will help your art.

  • Stefan Van Theemsche July 9, 2013 04:02 pm


    Photoshop also has the option to save to 32-bit format when using merge to HDR pro and then convert it to a tone mapped image via Mode in photoshop proper ...

    What's the benefit of using the photomatix plugin over the standard photoshop offers you?

    I'm being curious?

    I agree that overcooked HDR images are not particular nice unless you need a cartoonish result ...


  • Darlene July 7, 2013 09:29 am

    A.D. Just curious why do you feel I need more exposures? I shoot using the histogram as a guide for how far I need to go. Brightest one has details in the deepest shadows and no blacks clipped. Darkest has the opposite. What will more exposures give do you feel! Or do you mean less difference between brackets? Do you feel the final image is "poor at best" as you described? If so what is missing for you?

    I agree you can see 32bit full value on the Internet.

    @deb it's just a preference for the style of image you want. I prefer some tone mapped in Photomatix Pro and some 32bit

    @joe that is true but for me the time savings is worth it.

    @eric what is a "god awful burnt image" exactly? I'm not sure I know what you mean.

  • Rick July 7, 2013 05:43 am

    Waaaal. I don't own Lightroom, so I can't make that distinction....but I haff to say that the third photo in each set is Photomatix Pro. Look at the rails of the fence, and the driveway in the Oriental one. These show the fingerprints of Photomatix, to my eyes. Also the depth of field in the third Oriental shot seems strangely compressed.

  • Darlene July 7, 2013 05:07 am

    Hey guys thanks for the guesses. I'm actually in Portland, OR attending a conference where our very own Darren Rowse was on the stage a while ago. I'll get back to you with answers when I get better Internet access.


  • Eric July 6, 2013 01:48 am

    Great article! Most HDR's, no matter how tastefully done, still look like those god awful burnt images to me simply because they just don't look natural. But everyone has different tastes, and I can appreciate a good article all the same :)

  • stacie July 5, 2013 04:52 am

    Great article! It's always nice to learn something new about the technical side :)

  • Joe N July 5, 2013 03:06 am

    Great article and examples.

    If you own Photomatix Pro you already have the ability to save the merged files as 32bit You don't need the extra plug in. You will need to use both programs (photomatix and Lightroom) separatly, but the extra step is not that big a deal. The Photomatix site gives you instructions on how todo this (kudos to Photomaix for not making you buy both!!

  • Captain Photo July 4, 2013 11:56 pm

    Deb Scally, I guess it takes a woman to make the common sense no-brainier conclusion! I totally agree that the 32 bit method to HDR is probably best for beginning HDR enthusiasts and most of the others making and posting gaudy HDR online. I've been advocating it ever since the day Lightroom 4 was released. The Photomatix plugin wasn't out yet so I began saving and using the 32 bit file from Photomatix Pro. This workflow with 32 bit is so amazing and simple to learn I began calling it "The Perfect HDR Workflow" and teach it at with free video.

    HDR really is a great way to capture images today to render full dynamic range of our photos. Until camera sensors get better to do it in one shot, HDR is the new standard of realism. It's easy enough now that HDR comes into the realm that anybody can do it well and should not be afraid of it at all. With 32 bit HDR, the software is much less expensive too, because Photoshop is not needed to clean up the mess that conventional tone mapping does to your image. It's fast too... You can now make a Perfect HDR image in less than 5 minutes...not one or two hours. It's also easy, the first time yor try 32 bit, you get outstanding results you'll proudly post online.

    It's really great to see more photographers getting the message thanks to articles like this. Cheers Darlene, thanks for writing this and spreading the word!

    ~Captain Photo

  • Deb Scally July 4, 2013 10:57 pm

    Question: If 32-bit offers upgraded print and full resolution quality, greater lattitude in final LR adjustments, and it is THIS easy to accomplish as a plug-in to LR, why would anyone ever use Photomatix Pro the other way? Am I missing something?

  • Anthony Franklin July 4, 2013 10:34 pm

    Here are my guesses :

    Great article, great info Thank you..

    I think they are both in the same order..
    1: Lightroom 2: 32 bit 3: Photomatix
    1: Lightroom 2: 32 bit 3: Photomatix

  • laurent July 4, 2013 12:05 pm

    Here are my guesses:

    1: 32 bit; 2: lightroom; 3: Photomatix
    1: Photomatix; 2: 32 Bit; 3: Lightroom

  • Ivan Lerner July 4, 2013 07:34 am

    Agree with steve except for the last two of the oriental house, I think it is
    1: Lightroom; 2: 32 Bit; 3: 32 Photomatix
    1: Photomatix; 2: Lightroom; 3: 32 Bit
    because of the tree on the right of the image, wich seems more even with the image in terms of tone on the third image, sugesting HDR.
    I really liked this technique, not a fan of that grainier look.

  • Steve July 4, 2013 07:17 am

    Great article. Thanks. Here are my guesses:

    1: Lightroom; 2: 32 Bit; 3: 32 Photomatix
    1: Photomatix; 2: 32 Bit; 3: Lightroom

  • A.D.Wheeler Photography July 4, 2013 05:50 am

    Up for debate? There is no question that tonemapping at 16bit is nothing but a compromise. There is no way to see the REAL differences between 16 and 32bit on the web other than the reduction of haloing. The real difference is like working with JPG or RAW and the answer is just as clear. If you are into HDR and you want the most realistic looking, most user controllable light, least noisy, and non-compressed files to work with, 32bit is the ONLY option. The real differences can be seen at full resolution and are especially noticeable if you are printing your works. Once you learn 32bit, you will never go back. Most important tip to 16 or 32bit HDR NOT do what the author has done in the first sequence of shots. A scene with that much dynamic range needs more exposures. Otherwise you are leaving it up to the software to fill in the blanks and your results will be poor at best. The biggest mistake I see new-to-HDR photographers make is shooting too few exposures for what the dynamic range in the scene demands.