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Palmerstown River Estuary
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Three from this weekend. My first attempt at taking this type of photo. I think I prefer the shorter exposures rather than the one where the stars leave trails.
C&C welcome.
they are hard to see,i think a bit dark for me,but i’m no expert.
Sean.
These look nice Podge but a bit dark as Sean said. I presume you have raw files for these so you should be able to get them brighter in the raw converter, worth doing cause they look nice
M
Middle one works for me Podge – Great colours – although may get a bit noisy when bigger.
Gary
I’ve done some maths.
The middle one was for 2 mins at f5 ISO 400.
To reduce this to ISO 100
ISO400 – 2 mins
ISO200 – 4 mins
ISO100 – 8 minsand to reduce it to f8
f5 – 8 mins
f5.6 – 16 mins
f6.3 – 32 mins
f7.1 – 64 mins
f8 – 128 minsI reckon it probably should have been taken for 4 minutes to get the correct exposure which means
ISO400 – 4 mins
ISO200 – 8 mins
ISO100 – 16 minsand to reduce it to f8
f5 – 16 mins
f5.6 – 32 mins
f6.3 – 64 mins
f7.1 – 128 mins
f8 – 256 minsBetter bring lots of hot water bottles next time.
Your calculations falter slightly in the last section Podge-
you seem to be making full stops out of third stops-But if we take 20mins 5.6 (seems a lot)
then that should come down to about 40 seconds at f/1.2-Sorry, don’t know what focal length you’re using-
but it looks medium wide-j
Middle one for me too, the colours are just great. The first and second images with the short exposure look very dark.
Dave.
I thought there might be a mistake with the f stop sequence.
From this page (see fractional stops) – http://en.wikipedia.org/wiki/F-number
“the aperture that is one-third stop smaller than f/2.8 is f/3.2, two-thirds smaller is f/3.5, and one whole stop smaller is f/4. The next few f-stops in this sequence are
f/4.5, f/5, f/5.6, f/6.3, f/7.1, f/8, etc.”and the scale further down
“Typical one-third-stop f-number scale
f/# 1.0 1.1 1.2 1.4 1.6 1.8 2 2.2 2.5 2.8 3.3 3.5 4 4.5 5.0 5.6 6.3 7 8 9 10 11 12.5 14 16 18 20 22 “Does this mean that f8 is just 1 1/3 stops down from f5 ?
To simplfy things I think I should just take a test shot at f8 ISO1600 and then work it out as I did above to calculate the exposure time for ISO 100 ?
One stop is a multiple of “route 2” approx 1.414.
This is because doubling the amount of light hitting the film requires
doubling the aperture area. As area changes by radius squared, we use
a factor of route 2 instead of 2 to increase the aperture diameter.Hence f/2 + 1 stop = f2.8
f/5 + 1 stop = f7
f8 – 1 stop = f5.6
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