Good HDR, bad HDR, what's the difference?

I bracket every landscape that I photograph. There’s a good reason for that. I love to shoot into the sun.

Normally lit scenes are easily handled by today’s digital cameras. The range from highlights that you want to show detail to the dark shadows just before they block up can usually be captured in one exposure. Shooting into the sun greatly increases that range. You can try to capture everything in one shot but too often it is by sacrificing details in the highlights or important shadow detail. It is precisely for that reason that I bracket everything. It’s easier to keep the camera set for that and later delete the brackets that you have no need for.

The roadside shot above is typical of what I am usually trying to capture. I always have my camera set to bracket five exposures. Only four are shown here because the darkest one was too dark to be useful. In a pinch I might be able to use either of the top two images. I might be able to get away with less detail in the sky. Happily the two bottom exposures both have detail close to the sun. I used the four bracketed shots here but I think that I could have gotten away with using only three with an almost unnoticeable loss of highlight detail. The four images were exposed as RAWs and processed in a quality RAW converter. I leave the color balance to AS SHOT. The converter removes or reduces most of the chromatic aberration although the lens I use for this has almost none to speak of at the apertures I shoot at. It’s really splitting hairs.

I use RAWs because this ensures that I am getting ALL of the highlight and shadow detail that was recorded, ie, there is no clipping. I save the processed RAWs as 16 bit TIFFs. Why 16 bits when it increases the file size? Often having the extra image information means that I might not get any banding in my shadows, especially dark clouds.

Once I have my processed RAWs saved to my computer I import them into Photomatix. Where I think many beginners are mislead are by the default settings in the program. Photomatix allows you to save the settings you use. I have one saved that usually needs very little tweaking inside the program.

Someone asked in a previous post what a bad HDR looks like. The two images below are directly output with a couple of the Photomatix default settings.

Lovely aren’t they? LOL This is what most people think of when they think HDR. The one on the left doesn’t look too bad small. At a normal size the sky is full of noise and grain. The snow likewise is very grainy. It shows lots of detail like that but it is unnatural looking. The image on the right displays the classic HDR halos. They are very exaggerated compared to the left image but the left one still has a slight halo that is not noticeable reduced this small.

Above is what the Photomatix presets look like. Once in a while the Fusion presets will serve as a good starting point but ninety percent of the time I use my preset shown below.

Looking at my saved preset you can see how low the top slider is set. That’s the one that really causes a lot of problems. Sometimes when I want to get a bit more detail in my clouds I will process the RAWs twice. For the first image I use my preset. For the second one I will use my  preset as a starting point and then pull the STRENGTH slider up always watching for halos and noise. I save that and then in Photoshop copy the second image onto the first and with LAYER MASKING remove everything below the horizon, flatten the image and save.

Once I have tweaked my saved preset, processed and saved the image my work is still not done. It might sound like a lot of work so far but it only takes a few minutes.

With my image now in Photoshop I fine tune the color and tones. Photomatix gets you close but never so close that I can use that as my final. A few minutes later in Photoshop and below is the result. It is an HDR in the truest sense of the word but as you can see it doesn’t look like the two exaggerated presets that everyone seems to associate with HDRs.

There is no way with today’s sensors that I could have gotten this result with one exposure even with a graduated neutral density filter. One MAJOR DRAWBACK that nobody seems to talk about when darkening skies with graduated ND filters is the banding that usually occurs when you use a filter to reduce the amount of light. To do it this way gives the photographer a lot more control over image quality.

Also consider that once you shoot something with that filter it is almost impossible to undo it and if you’re going to shoot the scene without a filter as a backup then why not bracket in the first place?

Below is how I visualized this roadside scene just outside of Edmonton.

Happy shooting,

Dan

About these ads

~ by Dan Jurak on January 6, 2013.