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crystallography:collection:frx:usage [2016/07/12 07:41] bonnefoncrystallography:collection:frx:usage [2023/11/01 20:19] (current) – external edit 127.0.0.1
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-==== Rigaku FR-X Usage ====+====== Rigaku FR-X Usage ======
  
 Training on 2015.03.30 Training on 2015.03.30
  
-FR-X generator: 45 kV, 66 mA, 70 μ cross-section, 180 μ beam, 1.7 miliradians divergence+**FR-X generator** 
 +  * 45 kV,  
 +  * 66 mA,  
 +  * 70 μ cross-section,  
 +  * 180 μ beam,  
 +  * 1.7 miliradians divergence
  
-XG Control tells you the settings values (45 kV and 66 mA). Usually you can start collecting data 1h after setting the values.+**XG Control** tells you the settings values (45 kV and 66 mA vs 20 kV and 10 mA when not used) .  
 +You can screen as soon as the parameters have reached the target values, but wait one more hour to collect, so that the beam is stable.
  
-Pilatus 300K detector: 3 chips, shorter exposure time, no readout (no shutter closing), almost never overloaded (>1.5 millions), water circulation at room temperature, dry air+**Pilatus 300K detector** 
 +  * 3 chips,  
 +  * shorter exposure time,  
 +  * no readout (no shutter closing),  
 +  * almost never overloaded (>1.5 millions),  
 +  * water circulation at room temperature,  
 +  * dry air
  
 <code>>thread</code> command on camserver gives the temperature and humidity level <code>>thread</code> command on camserver gives the temperature and humidity level
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 Set the directory /data/user/project1_crystal1 Set the directory /data/user/project1_crystal1
  
-=== dtdisplay ===+==== dtdisplay ====
  
   * middle click > zoom area   * middle click > zoom area
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 ---- ----
  
-=== Index ===+==== Index ====
  
   * Refine in triclinic (P1)   * Refine in triclinic (P1)
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 ---- ----
  
-=== Strategy ===+==== Strategy ====
  
   * HKL_3000 strategy only works for single axis   * HKL_3000 strategy only works for single axis
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 Chi geometry goniometer, omega angle 180° follows the 2θ angle Chi geometry goniometer, omega angle 180° follows the 2θ angle
  
-XG Control tells you the settings values 45 kV (from 20) and 60 mA (from 10). +If you press ABORT, the connexion will be lost and you will need to re-initialize 
-You can screen as soon as the parameters have reached the target values, but wait one more hour to collect, so that the beam is stable.+Check the log on the MSCservdect window. 
 +To resume, check the parameters in the display. 
 +The scan number will be implemented. 
 + 
 +With a 3D window >1, the mosaicity box will automatically be checked 
 + 
 + 
 +---- 
 + 
 +==== Zoom window ==== 
 + 
 + 
 +**Box size**: (16 by defaultusually not necessary to change, even if there are neighbor spots in the box 
 +Int_box: red ellipsoid to integrate spot. The reject area is between the red and the white. Is it necessary to increase the size for the red ellipsoid (0.35 by default)? 
 + 
 +Changing box size also changes the spot size. Use the box size that gives the highest resolution for the red area (it depends if the number is odd or even). 
 + 
 +**Profile fitting radius** is the yellow circle. When ON, it display only the strongest reflexions. Increase (from 8 to 10) when there are less spots to have enough strong reflexions within the circle, otherwise HKL might reject too many weak reflexions. Don't use a too big radius because spot profile is different at the center and in the edges
 + 
 +**3D window**: number of consecutive images put together to estimate the mosaicity. Usually it covers the spread of the mosaicity ONCE, but set it to cover it TWICE. 
 + 
 +**Set shadow region**: the Mask for the beamstop is not critical. 
 + 
 + 
 +---- 
 + 
 +==== Integrate ==== 
 +  
 +All scans are processed 
 +χ² should be close to 1 
 + 
 + 
 +---- 
 + 
 +==== Scale ==== 
 + 
 +**Check the boxes**: 
 +  * Scale restrains 
 +  * Absorption correction 
 +  * Anomalous 
 +  * B restrains (HKL recommended) 
 + 
 +Have low reflexions marked for rejection. 
 +Scale several times until the number don't change anymore. 
 +If χ² is too low, decrease the error scale factor. 
 +Exclude frames if necessary. 
 + 
 +**For SAD phasing**: 
 +if χ² is high: increase the scale factor (up to 1.6) and the error model (up to 0.6-0.7), but it might kill the anomalous signal.  
 +Check the orange(merged)/blue(unmerged) plot on χ² : higher signal means higher gap 
 + 
 +**Use auto correction**: will try to reach a χ² of 1, but we don't know how, so be careful. 
 + 
 +---- 
 + 
 +==== Report ==== 
 + 
 +The log file contains merged I+/I- an the end of the file and tables with unmerged I+/I- in the middle of the file. 
 + 
 + 
 +---- 
 + 
 +==== SAD-Phasing ==== 
 + 
 +The sequence is necessaryGive the source or the signal or define if you have a heavy atom. 
 +Software used: Arp/Warp, CCP4-6.3.0, CCP4-6.4.0(Coot), ShelX 
 + 
 +**Data analysis**:  
 +Grey area 1.3 for anomalous signal (can be used up to 1.0) 
 + 
 +**Find sites**: 
 +Choose the resolution limit (>1.8 Å to distinguish disulfide bonds, test 0.1 Å increments) 
 +Check the absolute value and the spread of solutions (a few in the up-right corner) 
 + 
 +**Site view**: 
 +Sphere size correlates with the occupancy 
 + 
 +**Phase**: 
 +High resolution limit; try different resolution cutoffs 
 +  
 +**Check hand** (//ShelXE//): 
 +You should see the difference, dark red/dark blue, difference of one graduation in scale. 
 +If necessary, increase the cycle number so that a plateau is reached. 
 + 
 +**Phase**: 
 +//Mlphase//, //DM-phase extension// 
 + 
 +**NCS**: 
 +//DM// or //Parrot// (a bit better) 
 +At least try it if you have more than 1 molecule in the Asymmetric Unit 
 + 
 +**Build**: 
 +//ARP/WARP// for high resolution 
 +//Buccaner// for lower resolution (∼ 3 Å) 
 +Let ARP/WARP build/refine several times if has difficulties building. Start several times witha few cycles rather that once with many cycles. 
 + 
 + 
 +---- 
 + 
 +==== Molecular Replacement ==== 
 + 
 +**Analyze data** 
 + 
 +**Prepare Model**: Edit the PDB file (delete ligands, waters, side-chains if you want) 
 + 
 +**Run MR** (//MolRep//): 3 Å by default; rigid body at 3.0 Å, then refine at max resolution 
 + 
  
  
  
crystallography/collection/frx/usage.1468309287.txt.gz · Last modified: (external edit)