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Old 15-09-2010, 09:06 AM
TrevorW
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Problem with flats

I know this has probably been raised before but I used a EL panel for the first time the other night and all the flats did was make the image worse

they appear quite grainy

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Old 15-09-2010, 09:23 AM
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Octane (Humayun)
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Are your flat lights a fairly decent exposure length? And, are you moving the EL sheet around between exposures? Are you taking flat darks? Are you taking a sufficiently large number of them to give you an SNR of between 4-5?

H
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Old 15-09-2010, 09:41 AM
TrevorW
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Hi H

I took 40, 20 then rotated the EL panel 90 degrees and took 20 more, under Maxim the info window showed average 10000 aud, exposure length per flat was only .06 seconds

Cheers
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Old 15-09-2010, 09:51 AM
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Octane (Humayun)
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Hrm, I wonder if the exposure length is long enough?

Any chance of diffusing the light and taking longer exposures?

H
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Old 15-09-2010, 10:00 AM
TrevorW
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Probably could put a sheet of white A4 paper between I've heard this being done before might try that then take longer
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