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Dale, you are right, 12 bit doesn't increase the dynamic range, it just
gives you higher intensity resolution. However, this might be a good way
to go in this case, since it could help to distinguish different intensity
levels. In most cases it's not necessary to saturate regions of the scan
field, it's just about displaying the low intensities (look-up-tables
etc.).
Maria, could you provide a sample image? Do the stripes only appear in the
lines with saturation ("comet-tails")? Or in a regular way over the whole
image?
Regarding the scan speed vs. averaging, I have the impression that
averaging is the better way to go. With a constant light source as sample,
reducing the scan speed results in a rather linear decrease of noise,
whereas averaging gives exponential decrease. Based on these measurements,
up to 8 times averaging is better than decreasing the speed to the similar
period.
Michael
> Search the CONFOCAL archive at
> http://listserv.acsu.buffalo.edu/cgi-bin/wa?S1=confocal
>
> Double check the manual to see that this really gives you more dynamic
> range and not just finer resolution of the same signal range.
>
> Dale
>
> Jacqui Ross wrote:
>> Search the CONFOCAL archive at
>> http://listserv.acsu.buffalo.edu/cgi-bin/wa?S1=confocal
>> Hi Maria,
>>
>> What happens if you switch to 12bit imaging instead of 8bit? This would
>> give you a greater dynamic range so may help with the saturation
>> problem.
>>
>> Kind regards,
>>
>> Jacqui
>>
>>
>> *Jacqueline Ross *
>>
>> Biomedical Imaging Microscopist
>> Biomedical Imaging Research Unit
>> School of Medical Sciences
>> Faculty of Medical & Health Sciences
>> The University of Auckland
>> Private Bag 92019
>> Auckland, NEW ZEALAND
>>
>> Tel: 64 9 373 7599 Ext 87438
>> Fax: 64 9 373 7484
>>
>> http://www.health.auckland.ac.nz/biru/
>> <blocked::http://www.health.auckland.ac.nz/biru/>
>>
>>
>>
>> ------------------------------------------------------------------------
>> *From:* Confocal Microscopy List [mailto:[log in to unmask]]
>> *On Behalf Of *Maria Jimena Ortega
>> *Sent:* Wednesday, 12 March 2008 7:34 a.m.
>> *To:* [log in to unmask]
>> *Subject:* 510 meta: scan speed, saturation & stripes
>>
>> Search the CONFOCAL archive at
>> http://listserv.acsu.buffalo.edu/cgi-bin/wa?S1=confocal
>>
>> Hello,
>>
>>
>>
>> I am having a situation with a new 510 Meta from Zeiss and would like to
>> receive some feedback from other users…
>>
>>
>>
>> First thing I notice is that the intensity level varies a lot with scan
>> speed (from 3.2 usec/pixel to .64 usec/pixel). So, parameters choosed
>> at a speed doesn`t work in the other… it really annoying!
>>
>>
>>
>> The other situation is that when I am working at high speeds (0.8 – 1.64
>> usec/pix), average 4 line, if my image has saturating conditions ( I
>> =255, 8 bit) I see some regular “stripes”.
>>
>> Zeiss tells there is a security system (to protect the PMT), but I do
>> not understand why I see it in some speeds and not others, or why I
>> don`t get them in my Pascal… any clue?
>>
>> The situation is that I need to saturate some parts of my sample in
>> order to see the parts I am interested in!! What should I do?
>>
>>
>>
>> The also tell me not to make average and slow down speed… but I don`t
>> get the same results… Can someone help me in this scan speed vs average
>> discussion?
>>
>>
>>
>>
>>
>> Any clue would be gratefully received!
>>
>>
>>
>> Maria
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