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chiahaoliu / xpdAcquireFuncs

helper functions to XPD computer
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dark correction doesn't work properly #10

Closed chiahaoliu closed 8 years ago

chiahaoliu commented 8 years ago

Corrected image is incorrect. Need to review the code and see where does it went wrong

chiahaoliu commented 8 years ago

Possibly due to over-corrected, i.e. light scan time =0.2 s while dark count time unit = 0.5 s

sbillinge commented 8 years ago

try multiplying the dark by 2/5 before subtracting...does it fix the problem?

On Fri, Oct 23, 2015 at 5:14 PM, chiahaoliu notifications@github.com wrote:

Possibly due to over-corrected, i.e. light scan time =0.2 s while dark count time unit = 0.5 s

— Reply to this email directly or view it on GitHub https://github.com/chiahaoliu/xpdAcquireFuncs/issues/10#issuecomment-150694217 .

Prof. Simon Billinge

Applied Physics & Applied Mathematics Columbia University 500 West 120th Street Room 200 Mudd, MC 4701 New York, NY 10027 Tel: (212)-854-2918 (o) 851-7428 (lab)

Condensed Matter Physics and Materials Science Dept. Brookhaven National Laboratory P.O. Box 5000 Upton, NY 11973-5000 (631)-344-5661

email: sb2896 at columbia dot edu home: http://thebillingegroup.com

chiahaoliu commented 8 years ago

That could work but might potentially introduce unwanted error to dark image data. I am thinking to shorten dark scan exposure time to 0.2 s which is the lower limit of pe1 ,so that each dark image can be precisely used as a 'unit'. Also from I see from dark image data, electronic noise goes very small after first few frames, we could / might collect shorter time

chiahaoliu commented 8 years ago

Closed. Reproduce QXRD behavior