camera settings

[Sheema R]

Hello,

Thanks for the great package!

My question is about the camera settings. When I enter values for "camera response to photon" and "dark intensity", the reconstructed STORM image becomes pixelated. This makes me 

wonder if I'm not using the right values for camera. For data acquisition I'm using an ANDOR EMCCD DU-897E, according to the performance sheet @10MHz 14-bit EM amplifier with preamp setting of 1x the CCD sensitivity is 64.4 electrons per A/D

and base level is 386 counts, and single pixel noise is 98.53 electrons (I'm using an EMgain of 300). In RapidSTORM settings I used 64.4 for camera response to photons and 386 for Dark intensity.

I appreciate if you can help me.

Many thanks in advance,

Sheema

 

[Steve Wolter]

Hi Sheema,

two ideas:

• How many electrons per photon does the camera yield? You need this for the computation. We typically determined this experimentally by fitting the Poisson distribution of low-light background.
  
• Andor adds a constant offset to the camera's output, often 1000. This is the number you need in "dark intensity". Photon flux or electron background should not be added here, this will be handled as the background part of the model. The difference between the two is that the constant offset is constant, while the physical background is probabilistic and follows a Poisson distribution.

In general, the Maximum Likelihood estimator (which is enabled by these two parameters) has been tried by very few people. It yields a better precision in theory, but in practice it's really hard to determine and check the parameters.

Best, Steve

--
You received this message because you are subscribed to the Google Groups "rapidstorm-discuss" group.
To unsubscribe from this group and stop receiving emails from it, send an email to rapidstorm-disc...@googlegroups.com.
To post to this group, send email to rapidstor...@googlegroups.com.
For more options, visit https://groups.google.com/d/optout.