Ulysse Nardin

jeff m
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Very nice Was the Casio Digital or film emulsion? and some FYI Stuff

If it as digital I did not know the ASA would be that grainy. I'm into astrophotography( another expensive hobby!) and in longer exposures ASA 400 is still adequate to take photos. If you blow up the 35mm negative to an 8x10 it is only then you will start to see that famous grainy appearence. I'm sure you have researched. Please allow me to share w/ you.
FYI if you change perameters such as f/stop and exposure time by doubling the exp. time or +- 1 f/stop you will then double the brightness or decrease the brightness by one half, therefore, the same image will be achieved equally as bright holding everything else constant if you shot a pict at f/5.6 @ 1/30sec and f/4.5 at 1/60

Also the distance you take the photo must be the same distance every time. one of your photos is larger.(maybe u just enlarged in a photoshop program for clarity) the inverse square law says that if you double the distance you will decrease the amount of photons hitting the detector by 1/4 th (luminosity) and increase the area the photons strike by 4 times (photons will be the same # of them, just dispersed more). Try it w/ a flashlight: Take a distance and measure the area the flashlight casts upon the wall (3.14 x radius squared), then double the distance and remeasure the area.
Area should be 4 time bigger!

There is also something apparent in film emulsion which is called reciprosity failure.
Which means there is a finite amount of light the film will absorb in a certain time. after that the film has reached maximum absorption, no further light may be imprinted upon the film. So, I guess have answeared my question. This must have been a digital shot to achieve a 3 and 6 hour exposure. I like the digital picts nice and crisp and well documented. Looks like you had fun!

Regards

Jeff

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