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deadshot Sep 18, 2008 7:21 AM

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If you look at the photo I have enclosed you will see a fair amount of bloom/flare coming down from the top.It was taken in a very poorly lit castle ruin with a very bright sky. ISO 100 1/50th F3.5 Matrix metering.My questions are is this caused by the range of the zoom/amount of glass ,or poor technique.? I will send three more the next one I took using the AElock and metering off the sky more, which is more like the actual lighting.The following ones were adjusted using photoshop.

Any comments or advice is appreciated.


ReneB3 Sep 18, 2008 4:34 PM

This is one of the hardest situations to photograph in. This problem isn't limited to digital either, film was no better at capturing the bright and dark areas all in one shot. These photos are all about compromise. I try and limit the blown out areas by looking at the LCD with the highlights shown and keep them to an acceptable value. this will give you the most shadow detail. I find I can adjust some for shadows since there is data there but once it fades to white you cannot do anything with it. The ADR or whatever Nikon callsit does add a stop or so of dynamic range through electronic magic. Your eye can see about twice the dynamic range as the camera sensor or film and that's the real heart of the problem. It looks far better in the view finder than on the screen after it's shot. It looks like you have a handle on the Post Processing to get this at least better.

JohnG Sep 19, 2008 2:01 PM

as mentioned it isn't really flare. It's just the dynamic range is too great. There is some purple fringing where the blown-out sky meets the wall. That is fairly common when you have blow-outs like that - but better lenses do a better job of handling it.

There are several ways to address the situation:

1. Graduated nuetral density filter - this type of shot is what they were made for - basically one part of your image has a darkening filter and the other does not.

2. Blended exposure. This technique requires multiple images that are identical in composition just with different exposures. This can be difficult without a tripod to get the framing the same. Then using software you paint in one picture onto the other - so you may start with the castle as your base image and take the image exposed for the sky and paint in only the sky portion of that image.

3. Same as 2 except instead of 2 different shots you use a RAW shot with multiple conversions. You generally need to be within about 3-4 stops though. Given the great dynamic range of your shot this might not be possible. In this case you take a single picture with the metering just below the blow-out point (i.e. histogram pushed to the right but not yet clipped). You then do multiple raw conversions from that same file adjusting the exposure on each conversion. Then use the painting technique from step 2.

deadshot Sep 20, 2008 6:48 PM

Thanks for the comments, very informative and interesting.


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