Tag Archives: How many exposures to shoot

Using the Histogram to Ensure you have covered the Dynamic Range of a Scene

HisogramAs I discussed in this article: How many Exposures are enough the most important part of the -How many exposures do I shoot – is the fact that you need to cover the entire dynamic range of the scene. As the article pointed out the spacing between exposures was not AS important as covering the entire range.

In this article  Measure & Exposing for HDR I told you how to meter different areas of the scene to know the range of shutter speeds you would need to shoot to cover the dyanmic range. But even though it’s a good way to get you close, there still can be some margin of error because of course we know…sometimes the meter gets fooled. Continue reading »

Shooting the LOW dynamic range scene, and what exposures to leave out of any HDR

I awoke on Labor day Monday to rain. A rare summer occurrence in Southern California.  After I stopped off for a Smoothie at Jamba Juice  (Mmmmm). I headed down the road to the Vineyards of Wine country thinking there may be some cool shots because of the clouds. The rain let up enough for me to set-up amongst the grape vines.

The first things I noticed was that the light was VERY flat because of the cloud cover but the scene still had some interest to me. I measured the light range with my cameras meter from brightest to dark and the range only covered less than 3 stops. Now right there that should have told me not to shoot an HDR and I should have taken the advice I normally give and just shot it traditionally in one exposure. But two things came to mind, the fact that I am testing some new software and thought this might be a good test and also…well I just plain thought I could get just a little extra out of the sky with a 3 Exposure HDR shot at -2, 0 +2 EV.

Well, I was wrong. Here are the three exposures (Click to enlarge)

If you look at the -2 and the +2 exposures, you can see VERY little detail and definition to these two images and when we combine all three into an HDR the final effect is less than pleasing. And in the end, reflects the lack of any definition in those exposures and leaves us with an unusable image.
There is absolutely no detail in the vines. It is smeared and a total loss of tone.
So what should I have done. Well besides just working with one exposure. I should have known from measuring the dynamic range that if I did want to shoot 3 exposures, in this case I would have been much better off with 3 exposures but 1 stop apart -1,0,+1
 .
Was this shoot still salvageable, Yes it was. Since I was exporting the three images out of Lightroom into Photomatix, I merely changed the exposures of the RAW files in Lightroom to +1 exposure on the shadow image and -1 exposure on the highlight image. If you are using Photomatix or any HDR program as a stand alone program. You can accomplish the same thing by first processing the images from  the RAW file withy the exposure adjustments and then save as 16 bit Tiff files and open them in The stand alone program

In the end, I’m still not happy with this image. The light was way too flat for any drama whether it was a single image shot traditionally or an HDR. I should have known better. But sometimes these things work out
 So what else can we take away from this example. Even if you are shooting a wide range of exposures in a very high dynamic range scene, examine those images in a browser first to see if there is any detail in the extreme exposures that will be of any use.
Again while I was doing some tests on new software I made some exposure over a wide range, 9 exposures in all. But I ended up only using 7 of these in the final HDR because the two end exposures lacked any usable detail and would have just smeared the final product
 More isn’t always more and sometimes less is more
Hope that helps
PT