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woelen
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Do not get surprised if you need very long exposure times. I have done quite a lot of old-fashioned photography and for me, an exposure of 1 minute is
nothing special when using standard 100 ASA films. At twilight, exposure times already go up to half a minute with aperture settings of f/8 or so and
when it is dark, required exposure times may well be multiple minutes.
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blogfast25
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Thanks Woelen, but I'll try and improve things 'the digital way'!
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not_important
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And because of that not uncommonly used for courses in advanced snogging....
More seriously it can take quite long exposures, doing a series with big increases in exposure time can be used to bracket the needed time, followed
by a series with lesser steps in increasing times to get the needed time, is usually needed when first using a particular setup.
The difficulties with using lower end digital cameras is when some folks have gone with cobbling together a system with the CCD and support chips, but
their own controller and software. May digital cameras switch to lower resolution modes, including ones that enable adjacent pixel summing, for low
light levels or fast exposures; this can really drop the resolution. Doing your own controller means you can do long exposures at full resolution,
some even add TEC cooling to reduce dark current and noise.
For elemental analysis, an arc/spark between iron electrodes was a common source of reference lines, Fe having a a large number of lines in the
visible and UV makes it useful for identifying lines in a sample.
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blogfast25
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not_important: Yes, I’m aware that there are people messing about with the optical part of digicams and using their own controller software but
that’s not for simpletons like me. I’m just gonna plow on to my Bunsen-Kirchoff – grating/swivel instrument for best identification of single
lines… Thanks for the tip on Fe arcing: makes a lot of sense!
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