First HDR Attempt at night - Thoughts and assistance

[shaknbak]

Hello good folks of CiC. I thought I would take a stab at HDR in a night setting last night and took a shot of the Clark Bridge in Alton, IL. After bracketing 5 shots going from -2 to +2 stepping at 1 on exposure and pulling the files into CS5 and compiling the HDR I ended up with the below. To be honest I'm not happy with how it turned out and I'm not completely sure where I went wrong. First of all I don't see much difference between the HDR file and one shot at normal exposure. Secondly, the HDR version did some funky stuff with the area around the lights. Perhaps this just wasn't a good time or setting to attempt an HDR photograph and if that's the case I can accept that. I will continue to bracket my shots to see which kind of setting it makes the most sense but the blown lights at the top of the bridge with the darker colors underneath seemed like a good shot to give it a go. A couple of questions. Have other members turned out good results with CS5 and generating an HDR file and if so may I see examples? Additionally (and possibly part of my problem), I couldn't seem to find a way to zoom in on the initial HDR configuration screen in CS5. using ctrl & + zoomed me in a bit but not enough to see the kind of changes I would like to see by moving the sliders. Is there a better way to see what the results are of changing the sliders that I missed. Also worth mentioning that I used local adaptation when generating the HDR.

Perhaps I just didn't start with the correct exposure and that's also my problem.




This is one of the bracketed shots:



Any comments or thoughts are welcomed.

Thanks,

Gregg

[FrankMi]

Hi Gregg, looking at the normal exposure image you likely didn't really need to process as an HDR. However, the HDR processed image did pick up detail under the bridge and didn't blow out the bridge's mast heads. You likely could have recovered those by blending parts of the +2EV and -2EV images with the normal image.

You may want to play with the sliders a bit but as I don't use CS5 to do tonemapping (I use Photomatix then import into CS5 for blending), I'm not sure what options you have available. If I get a chance, I'll run your normal exposure image through single image HDR processing in Photomatix and see what I can get for you.

[shaknbak]

Thank you kindly for the response Frank. I certainly appreciate you taking a look. I'll have to play around with a couple of the exposures as layers and see what I can come up with. I recently upgraded to CS5 and I'm still learning what's new from PS7. Quite a bit has changed for sure. I thought there was supposed to be some added noise reduction features as well and I'd like to find out more about that as the images do have a little more noise than I was expecting. Perhaps I should stop looking at the images at %150 .

[FrankMi]

I certainly appreciate you taking a look.

Hi Gregg, I really like your shot of the bridge and marina. The second image you posted was a BMP so I had to make a JPG copy before I could try it in Photomatix. In Photomatix, the best renditions I felt were with the Typical and Smooth presets.

I also opened the JPG in Adobe Camera Raw and adjusted Recovery and Fill Light to pick up some of the blown highlights and shadows (not surprising given the time of day and the fact that it is a single exposure).

I opened the BMP, JPG with ACR adjustments, and both tonemapped images as layers in Photoshop. The JPG with ACR adjustments looked best so I used this as my starting point and blended back in from the other images as follows:

From a copy of the JPG with ACR with the brightness decreased, I blended in the bridge towers and supporting wires.

From a copy of the JPG with ACR with the brightness increased, I blended in the underside of the bridge roadway, foliage and water.

From a copy of the Default Tonemapped image I blended in just the sky.

There wasn’t anything in the Smooth Tonemapped image that would benefit so I didn’t use this layer at all.

I noticed a lens flair just above the right hand pole so I cloned that out.

I finished with a slight sharpening of the entire image with Unsharp Mask at 100% and 0.3 pixels.

In the end, this image benefitted very little from HDR technique with only the sky being partially blended in. HDR doesn’t need to be applied ‘en mass’. In some cases most of the image can benefit but in others, such as this one, there was very little to be gained.

When I am making changes to an image I am sometimes working at as much as 500% with brush sizes as small as 5 pixels so I wouldn't be concerned about pixel peeping for making the changes. On the other hand, I rarely view an image at anything but full size. If there are no issues at full size, you're good to go in my view.



I expect that you can do better by using the +2EV, Normal, and -2EV images for your blending in Photoshop. Hope this Helps!

It is surprising how many stars in the sky you can see when viewed in the lightbox!

[shaknbak]

Hi Frank. Thanks for putting the photos through the Photomax paces. I tinkered around with using the +2EV, Normal and -2V files and worked with blending the layers and ended up with about the same results. I do like how your results show more of the light beams that are lighting the mast heads. I may have to go back on a night that has a little more moisture in the air and see if I can pick that up more in the shot.

As an aside, I find it interesting to see the water line stains on the concrete and where that line is in relation the roof line at the marina. The Mississippi can certainly raise up and out of her banks.

Gregg