HDR Photography

Hi All,

Has anyone experimented with HDR and the possible use of auto bracketing to achieve this effect? As you all know the K10D has 5 exposure capability on auto bracketing, is this enough and how can I achieve this effect?

Yes.

Setup 5 shot auto bracket, 2Ev apart.
Use Av mode (the aperture MUST not change!)
Use a tripod, of course.

Shoot the 5 shots and merge with your favourite HDR app (I use Artizen).
Not all HDR apps can handle movement between the frames so well (Adobe CS2 is pretty terrible actually!).

And use the Search facility of this forum - it's been discussed quite a bit over the past 12 months or so

Hope that helps!
Matt

Cheers Matt,

I wasn't sure what steps to bracket for. Will give it a go during the xmas Hols!!

Id personally use RAW format than 5 seperate shots, but thats just personal preference, it also means that you dont need a tripod
Is the quality better with bracketted shots merged to hdr?

Hi ikillrocknroll,

Please explain more or send a link to a previous discussion!!

Regards,

johnny_rino

If you take pictures in RAW - an uncompressed format (PEF on pentax cameras, and also DNG on the K10D I think) then in photoshop, or a RAW converter, you are able to "change" the exposure of the picture (basically, alter the brightness of it) and thus save 3 or 5 versions of the same image, with different exposures, to combining to HDR. This is different from taking one shot in JPEG format and changing the brightness and combining to HDR because in a RAW format image, a lot more information is stored, however they do take up alot more room on your memory card

Hi ikillrocknroll,

Look forward to trying both ways out. Thanks for the tip!!

Just to augment what is said:

I always shoot RAW. There are times when some delicate curves adjustment will bring in "HDR" (not true HDR) and handle deep shadows and highlights. However, there are times when HDR (that's 32-bit per colour channel) is needed. And this is how I work it:

1. Shoot RAW
2. Shoot 3 or 5 exposures, 2Ev apart
3. Bring them all into my RAW converter
4. Leave the exposure, curves etc all alone
5. Set the white balance and colour for them all - everything has to be set exactly the same for each RAW shot
6. Develop to 16-bit TIFF
7. Bring the TIFFs into Artizen and merge into HDR
8. From the 32-bit per channel image you then need to tone map back to a single 16-bit image.

It takes time, patience and practice - and a whole lot of hard disk space and RAM. But if you can recognise when you need absolutely massive dynamic range (talking more than 10Ev apart) then HDR is the way to go.

(This is HDR in the above way: http://www.mattmatic.co.uk/photo465791.html )

That said, 95% of the time you'll only need a single RAW shot (perhaps with ND grads). Always expose to get the highlights just in the histogram - if you blow out the highlights you can't recover them. If you can get the shadows just in as well, then you don't need HDR.

And then there's Photoshop (Elements as well) with the "Shadows/Highlights" which will balance things out for most shots.

Just remember that deep shadows will have much more image noise
Matt

Yeah that way is the best way if you have a tripod If not, then you can just use one RAW, and alter the exposure in your RAW converter. It gives lower quality results if your original image is more underexposed or overexposed (because detail is lost) but otherwise it seems to be okay

I use Photomatix Pro, any idea whether Artizen is better?

Example of my technique using Photomatix:
http://img265.imageshack.us/img265/7774/flyinggrassstainsbydeepja1.jpg

and i found a tutorial on this technique if you're interested]
http://www.gfxvoid.com/forums/showthread.php?t=26130

Yes

Photomatix Pro is easy to use and does produce good results. Artizen is clunky in terms of user interface, but what it excels in is its choice of tone mapping operators (They're probably similar in terms of handling compositing multiple images where elements have been moving)

And I think Artizen is cheaper
Matt

I've shot a lot of HDR recently (pretty much exactly the same way that Matt has gone about it, except I use Photomatix Pro). A five (or even 3) shot bracket will almost always produce a better image than a single shot processed several times.

I know some people use the single-shot approach if they don't have a tripod to hand, but I've found the auto-align option in Photomatix to work well (but a tripod is preferred)

EDIT:

You can find out how to get a discount on Photomatix from this HDR tutorial http://stuckincustoms.com/2006/06/06/548/