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Dear All,
To close this thread properly, I thought to share with you the below info.
As some of you have mentioned already, starting with the LSM 8 family, the
photon-counting module is not included, unless one purchases the FCS
module. It is upgradable, but depending on whether one has the 32-channel
QUASAR detector or a GaAsP detector the upgrade is different.
For the 32-channel, one would need a hardware component and the
photon-counting software module. For the GaAsP detector, the hardware is
already there, just need the module. This is true for the LSM 9 family too.
Thanks all again.
Best regards,
Nadia
On Tue, Jun 22, 2021 at 9:18 AM Nadia Halidi <[log in to unmask]> wrote:
> Dear All,
>
> Thank you for the feedback and additional helpful info.
>
> Indeed, both my ex-710 and 780 came with it. I did not notice on the 880
> because it came with the FCS module. But good to know this is the case now.
>
> Thanks all again.
> Best regards,
> Nadia
>
> On Mon, 21 Jun 2021 at 20:35, Benjamin Smith <[log in to unmask]>
> wrote:
>
>> *****
>> To join, leave or search the confocal microscopy listserv, go to:
>> http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
>> Post images on http://www.imgur.com and include the link in your posting.
>> *****
>>
>> One other quick point, in my experience PMTs make relatively poor photon
>> counters. The nature of the multiple dynodes decreases the precision of
>> the timing, and there also tends to be a lot of background thermal noise.
>> I've found hybrid detectors to be the true champions of photon counting,
>> especially the latest generations that can count at very high rates.
>> SPADs
>> are also fairly accurate and have low noise, but their counting rate is
>> pretty slow compared to hybrid detectors since the circuit has to be reset
>> before the next incident photon can be detected.
>>
>> On Mon, Jun 21, 2021 at 11:01 AM Craig Brideau <[log in to unmask]>
>> wrote:
>>
>> > *****
>> > To join, leave or search the confocal microscopy listserv, go to:
>> > http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
>> > Post images on http://www.imgur.com and include the link in your
>> posting.
>> > *****
>> >
>> > I agree with Mike on this point. The loss in dynamic range you accept
>> for
>> > single photon counting is only worth it when your samples are emitting
>> very
>> > infrequently. The only time I've used single photon counting is for CARS
>> > microscopy (and my second iteration of the system abandoned single
>> photon
>> > for conventional because I was able to increase my signal dramatically)
>> and
>> > FLIM which requires clocking of the incident photons. I could also see
>> it
>> > being useful for single-molecule or other samples where your
>> fluorophores
>> > are sparse, but for most applications your photon production rate will
>> > cause too much pile-up. In short, I would only recommend photon
>> counting if
>> > your application directly requires it.
>> >
>> > Craig
>> >
>> > On Mon, Jun 21, 2021 at 11:18 AM Michael Giacomelli <
>> > [log in to unmask]> wrote:
>> >
>> > > *****
>> > > To join, leave or search the confocal microscopy listserv, go to:
>> > > http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
>> > > Post images on http://www.imgur.com and include the link in your
>> > posting.
>> > > *****
>> > >
>> > > Hi Nadia,
>> > >
>> > > Photon counting requires additional hardware and changes the detection
>> > > electronics, so adding it is not free. In addition, there are some
>> > > tradeoffs to consider. For a PMT with zero dark counts, photon
>> counting
>> > > will increase your sensitivity per photon by about 15-20% due to
>> > > elimination of excess noise. However, since pulse pile up becomes an
>> > > issue, the maximum number of photons you can detect is reduced by at
>> > least
>> > > 1 or 2 orders of magnitude. Thus even in the best case scenario, you
>> are
>> > > accepting a very large reduction (>10 fold) in maximum shot noise
>> limited
>> > > SNR in order to gain a small increase in SNR for less bright samples
>> (<
>> > > 20%). In reality, the benefits may be even lower if your PMT has a
>> lot
>> > of
>> > > dark noise, which is why Hamamatsu sells the 'P' (photon counting)
>> models
>> > > of their tubes that are binned for lower dark noise.
>> > >
>> > > For a lot of users, it may not make sense to pay for the additional
>> > > hardware (and possibly special PMTs) for such a small benefit,
>> especially
>> > > if they will rarely or never use it. In my case for example, I did
>> not
>> > > include PC on any of my lab microscopes because for the range of
>> samples
>> > we
>> > > image we can always get higher SNR by operating outside of the PC
>> regime.
>> > >
>> > > Mike
>> > >
>> > > On Mon, Jun 21, 2021 at 7:46 AM Nadia Halidi <[log in to unmask]>
>> > > wrote:
>> > >
>> > > > *****
>> > > > To join, leave or search the confocal microscopy listserv, go to:
>> > > >
>> > > >
>> > >
>> >
>> https://urldefense.proofpoint.com/v2/url?u=http-3A__lists.umn.edu_cgi-2Dbin_wa-3FA0-3Dconfocalmicroscopy&d=DwIBaQ&c=kbmfwr1Yojg42sGEpaQh5ofMHBeTl9EI2eaqQZhHbOU&r=0LyF_z8oU1XGGyisIeOIXyIGIM5IYb3NcLjxHjUca5Y&m=B39J9izsUV-nAuw1gJx_e2EBFbh6Se1rrz5U9rGlJOk&s=_scJRvrz-T0hiK1HXmICYcC3ZrIjpA3WRDgBOslyWdE&e=
>> > > > Post images on
>> > > >
>> > >
>> >
>> https://urldefense.proofpoint.com/v2/url?u=http-3A__www.imgur.com&d=DwIBaQ&c=kbmfwr1Yojg42sGEpaQh5ofMHBeTl9EI2eaqQZhHbOU&r=0LyF_z8oU1XGGyisIeOIXyIGIM5IYb3NcLjxHjUca5Y&m=B39J9izsUV-nAuw1gJx_e2EBFbh6Se1rrz5U9rGlJOk&s=DICmw-Whp4hDz79Jc8t2mMDVF3Z5_EVIHeK6HGjbgeI&e=
>> > > > and include the link in your posting.
>> > > > *****
>> > > >
>> > > > Dear All,
>> > > >
>> > > > We recently bought an LSM980 with a GaAsP detector and it shocked me
>> > that
>> > > > we don't have the photon-counting mode. Is it normal that it is
>> > something
>> > > > that needs be to requested or separately bought for a GaAsP
>> detector?
>> > > >
>> > > > I would have thought if someone buys a GaAsP or spectral detector
>> > > > photon-counting mode should come with it, but with any PMT really!
>> > > >
>> > > > What do you think?
>> > > >
>> > > > Kind regards,
>> > > > Nadia
>> > > >
>> > >
>> >
>>
>>
>> --
>> Benjamin E. Smith, Ph. D.
>> Imaging Specialist, Vision Science
>> University of California, Berkeley
>> 195 Weill Hall
>> Berkeley, CA 94720-3200
>> Tel (510) 642-9712
>> Fax (510) 643-6791
>> e-mail: [log in to unmask]
>>
>> https://vision.berkeley.edu/faculty/core-grants-nei/core-grant-microscopic-imaging/
>>
>
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