Pseudo-HDR: Half-Assing Your Way To Fame And Fortune

We talked about HDRs before – they’re great, right?  The problem is you need three (or more pictures), you need to have your camera set up right, you need to bracket your shots (which might not happen automatically) and you need to take them all pretty quickly without anything moving between shots.  That’s hard, or at least inconvenient.  Well the good news is there is a way to fake an HDR from just one RAW file – something you might already have a stack of if you’ve got a DSLR.  Alright – let’s get going.

This morning I jumped out on the balcony all bright and early, just for you.  Yes you.  First, let’s go whole hog: Camera set to Av (aperture priority), I cranked out three bracketed shots (-2, 0, +2) of the sunrise.  I then use Photomatix Pro (which I said I don’t use) to combine them into a Tone Mapped HDR.  I’m using Photomatix here because Photoshop kinda chokes on this kind of thing and I wanted a comparable image.  Behold the magic picture below, in all its funny HDR glory.

Sunrise HDR

You wanna hear the rest of the story?  Hit the jump.

So what if you only had the “regular” exposure shot of the three used to create the picture above?  Well here is what you gotta do.  RAW images save all of the data the camera had when it took the picture, instead of doing some processing in an attempt to make the best picture in camera.  This is super handy for getting your white balance right, but it’s also pretty good for changing your exposure.  Open the RAW file in Adobe Camera Raw or your RAW editor of choice.  Tweak any settings you feel like, but then set exposure to -2 and save a copy.  Do it twice more at 0 and +2.  Now you have three identical pictures with different exposures.  If you combine these in Photoshop it will bitch at you, but it will also kinda mangle things, hence the goofy (but fun) Photomatix.  It is probably going to choke too – it knows these are the same picture, so it’s going to need you to manually specify which one is -2, which is 0, and which is +2.  No problem, right?  Combine into an HDR and then Tone Map them.  I didn’t twiddle any settings, just so you could see the difference:

Sunrise Pseudo HDR

So what do you think?  Obviously the colors are a bit different, there is less richness in the Pseudo-HDR, and the most obvious difference, it kinda blows up the gradient in the sky pretty good.  However, it looks like an HDR, right?  You know the alignment is going to be good (very nice if you’re taking pictures of the water or something moving at speed) and you didn’t have to bracket (which also means you probably didn’t need a tripod).   If you already shoot in RAW, it’s a good thing to know.  If you don’t shoot in RAW, you might want to remember this if you think you might want to fake yourself an HDR for fame and fortune.

3 Comments

  1. Thomas Kincaid is evil. I like this way better.

    I’ve played around with the 1-RAW method with Photomatix. I’ve also managed some interesting results by lying to it about how many images I have… eg 2 JPEGS, and saying one is both -1 and 0 stops, which allows you to get some HDR/tone-mapping fun with even less to start with. In some cases, I was able to use this method to fix minor problems like faded skys and too-dark corners enough to make the image more interesting for personal/web use, although the quality is acceptable for not much else. Let’s see more!

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  2. Ooh – the painter of LIGHT! Fun stuff, that guy. I’m also curious to see what happens if you take one RAW and turn it into 5 or 7 images – I wonder if you can smooth out the gradients more that way… hrm…

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