Detectors

[M Wilce]

I am in the process of selecting a SAXS instrument to purchase and I have a question regarding the Anton-Paar SAXSess instrument (I have decided not to include the WAXS option.)

I have been told that I have the choice of one of three detectors: IP, CCD or silico diode array.

Do any of you have any advice on which would be the best detector option. My lab studies proteins and protein/oligo nucleotide complexes.

Thanks in advance,
Matt

[weifeng.shang]

If the instrument must be from Anton Paar, I have the following comments. Our experiences at the beamline at X33 in Hamburg suggest that image plate is better than CCD because of the lower readout noise. We had no experience on silicon diode array. It is not a well established detector for SAXS. You have to ask the provider about the spatial resolution, dynamic range and background noise etc.

[weifeng.shang]

If the provider does not need to be Anton Paar, have a look at the model S3MicroPix from Hecus, which is to my knowledge the best for solution scattering.

[moitzi]

The silicon diode array detector is the so-called Mythen detector from Dectris. It uses same technology as the Pilatus detector from the same company which is also used at the EMBL. The Mythen, however, is a 1D detector with a rather small pixel size of 50µm in the direction of detection (compare pixel size of Pilatus: 172µm). This small pixel size is indispensable for a SAXS instrument as compact as the SAXSess. For isotropic samples 1D detection is usually sufficient.

[SAXSIST]

since 1993 every year a better detector has been published for SAXS, so I wounder why we are still looking for one?
Your question is very reasonable and valid.
If you want we can have a detailed discussion on that topic.

[SAXSIST]

... for SAXS 1D-PSDs I can recommend the MioStar I detector, for 2D-PSDs I would suggest a detector from Dectris, e.g. 2D Pilatus3 1M Detector System.
You can find a good overview of detectors at the Austrian SAXS beamline Elettra in Trieste (https://www.elettra.trieste.it/it/light ... l?showall=).
Hope this helped.
best regards,
Saxsist