FindDQE

Hello,

I tried the Find DQE program this week on a beam stop image that I collected during a Leginon session on a Tecnai F20 operating at 120 kV. I'd like to confirm that I've run the program correctly:

Is it correct to assume that since I was using a dose of 25 e-/A2, the total number of electrons/pixel is 25?

Upon request of a few sites, I wrote up a little doc describing the steps to integrate SerialEM with new Gatan K2 camera on FEI Tecnai scope.

http://www.bio.brandeis.edu/KeckWeb/emdoc/en_US.ISO8859-1/articles/setu…

Hope it is helpful.

I´ve just seen your work published in Structure journal about the recording of movies and alignment of frames to correct instabilities of the sample in cryoEM. Amazing.

In our center, we'd like to install a new digital camera for a 200 kV Jeol microscope. Currently we work with a Gatan CCD.

Before going further I would like to have your opinion about the available DDDs. You used the DE-12 from Direct Electron for your work and we could purchase the DE-12 also for our instrument but we could also upgrade to a DDD from Gatan.

Do you have experience with more than one brand of DDD?

We are testing our new direct electron detectors (FEI Falcon and Gatan K2 Summit). Rachel Ruskin in the lab started comparing Thon ring patterns (see attachments) calculated from images of amorphous carbon film using the Falcon detector and Gatan US4000 CCD (scintillator-based):

Microscope:	FEI TF20
Voltage:	200 kV
Magnification:	29,000

Dose rate:
Falcon:		30 electrons/Å2/second
US4000:		25 electrons/Å2/second

Exposures:
Falcon:		0.4 sec, 1.0 sec, 5.0 sec, 7.5 sec
US4000: 	0.4 sec, 1.0 sec, 5.0 sec, 10.0 sec, 20.0 sec, 40 sec

Dose/pixel: