Following my gallery post of Moon, Clouds and a Reflection I thought I would post a bit of an explanation for anyone else considering trying it.
For me the most striking effect on the long exposure background was the ghost reflection. Sassan has probably correctly attributed this to a reflection from the filter. In this case a Nikon L1A. Until the total cloud cover we now have goes, I cannot check this out. I have attached a composite of 2 images taken immediately one after the other but with a slight change of moon, re-positioning in the frame. It was fairly windy and the degree of cloud move is quite obvious when comparing the 2 shots.
Also attached is a composite showing the two images used in making the final. The most obvious thing to note is the exposure difference - 8 stops. The moon itself on the background exposure is totally burnt out and part of the shadow area is recorded. A problem with the long exposure required to get some detail in visible clouds is that high ice cloud, if present, will also be recorded. Fine for a nice effect but unless you are a digital darkroom wizard it does present problems when combining two images. The problem to be overcome is shown well in the ' Moon Move Overlay ' image.
The overlay of the 2 images shows the degree of movement by the moon during the 1 sec exposure. The overlay was lined up with the rear visible detail. To arrive at the final image the perfectly exposed moon was brightened to not look stuck on, and size increased to 105%. Although at this size in the final shot there appears to be a bright ring around the edge of the moon, when viewed at 300% there is detail almost to the edge allbeit faily bright. Shrinking the image has lost this. Merging the two together at this point with the clone brush took well over an hour as the final edge had to be blurred and not sharp. CA at the bottom of the moon was left in as to have removed that would probbly have taken another hour or more. Something I will do at a later date.
Lessons learnt for a future go is to take the cloud exposure and the final moon shot within 10 minutes of each other. As the sun moves so does the angle of the visible edge section of the moon. Unless the moon itself in the base exposure is in clear black sky there will be problems combining the images. I failed to do that on my first trial on Saturday night.
Stevie advises me that if the conditions are good we should have a Harvest Moon between 4 - 7th October. The moon will be full on the 7th.
Don
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