It was a blend of several pics taken at different exposures and merged in photoshop using the HDR function. This looked a bit artificial and your comments reflected that view.
I have had another attempt using the Digital ND Filter technique as described by Fred Miranda on his site and copied below for anyone interested.
Here is the O'Reillys sunset photo revisited with this much simpler tecnique and in my view the better.
Would appreciate any comments
Digital ND Grad
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HDR Merge
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Here are the steps for Digital ND Grad filter:
1) Take two pictures. One picture should be well exposed to the foreground, with the background overexposed. For example, if your background is a bright sky, the sky will appear overexposed since you've exposed for the foreground. Let's call this first image "Overexposed".
Then, for the second shot, do the exact opposite. This time your foreground will appear "underexposed", and your background well exposed.
2) Bring both images into Photoshop. Make sure you convert them to 8-bit mode.
3) Drag the overexposed picture on top of the underexposed one, while holding the SHIFT key. This will place them into 2 perfectly aligned layers.
4) Make a layer mask for the "overexposed" image by clicking on the layer mask icon at the bottom of the layers palette.
5) Click on the layer mask to make it active, and then select the linear gradient tool.
6) Drag a line from the top of the image toward the bottom until you reach the part of the image that it's not overexposed
The gradient you just created on the layer mask is the "digital split density filter". Now you can control the intensity of the effect by using the "Opacity" slider.
*Note: Raw shooters only need 1 RAW file converted to 2 images. First convert your RAW file into a non-linear image (overexposed). Next, convert the same file to a linear image (underexposed). Then, follow the same steps. Place the underexposed image on the bottom layer and the overexposed image on the top layer. For the non-linear file, use "High" contrast when converting the RAW file.
So, the next time you are out there shooting, if you accidentally forget your gradual filter -- don't panic. Now you have a new technique to help you save those once lost images.
Bob G