About MacCHESS

		Starting from 2003, all x-ray operations at CHESS run in a fully dedicated mode. This has numerous advantages for macromolecular users, including long fills, brighter beams and improved beam stability.
		Time is open for both new and existing users on the macromolecular ID beamlines. Time is awarded based on peer review of the proposed science, with short Express Mode proposals and rapid review available along with traditional Program Proposals.
		Proprietary review is possible for industrial users, or others, concerned about privacy. We strive to be accessible to groups that are new to CHESS, especially investigators that have not yet benefited from the MacCHESS facility.
		We now have a crystallographically trained staff available to help all macromolecular users with data collection and structure determination.
		Because of the high cost to travel to Ithaca, we will consider providing the data collection service in limited cases, where the user only ships the samples. Please contact me if you are interested.
		Quan Hao qh22@cornell.edu

Current station CCD configuration

		A-1	ADSC Quantum-210 CCD detector (four 2048x2048-pixel modules), monochromatic radiation at 0.976 A. Currently crystal-to-detector distance can run from 99 mm to 445 mm.
		F-1	ADSC Quantum-4 CCD detector (four 1152x1152-pixel modules); dual ADSC Quantum-4 CCD detector configuration; monochromatic radiation at 0.916 A. Currently crystal-to-detector distance can run from 45 mm to 900 mm.
		F-2	ADSC Quantum-210 CCD detector (four 2048x2048-pixel modules); MAD 0.77-1.60A. Currently crystal-to-detector distance can run from 53 mm to 569 mm.

Computing facilities

		For 2005, MacCHESS data collection computers at each beamline have been replaced with Linux machines. An additional Linux machine and an 'Alpha' Unix workstation are located at each beamline for data processing and backup. Additional Linux computers and Alphas may be found in the computer room, where two of the Linux machines (kaoline & opaline) are equipped for 'stereo' graphical use. All MacCHESS data collection/processing computers are linked via gigabit ethernet. The Unix and Linux computers have a variety of data processing software (see below) along with common crystallographic software including CCP4, Solve, pymol, O and SnB.
		Apple Mac computers are stationed at F1 and in the computer room for data backup. Currently the Macs do not have a lot of crystallographic software.
		By early 2006 the remaining Alphas will be phased out. Availability of tape drives, which require SCSI interfaces, will be reduced as well.
		David Schuller djs63@cornell.edu

Current data processing

		HKL-2000, a new program package based on extended versions of Denzo, Xdisplayf and Scalepack, is available on all the MacCHESS computers for processing data from all the detectors used on stations A-1, F-1, and F-2.
		DPS/mosflm/CCP4, version 2.03, for all detectors at CHESS. A tutorial on running this package is available in the "Processing data" section of these web pages.
		The HKL package, comprising denzo, xdisp, and scalepack, is available on all the MacCHESS computers for processing data from all the detectors used on stations A-1, F-1, and F-2. The current version is 1.96.6.
		Xdisp/denzo/scalepack, version 1.96, for Fuji images. Mccview front end for convenience.
		Marian Szebenyi, dms35@cornell.edu

Cryo equipment

		All macromolecular stations have been equipped with new Cryostreams 700 series from Oxford Cryosystems http://www.oxfordcryosystems.co.uk/cryo/cryostream/700series/index.html
		The temperature is usually set to 100 K, but can be varied from 80 K to 400 K. The systems can be programmed to cool down or warm up with a specific gradient, reach certain set points and hold these for a certain amount of time. The cold gas flow is variable and can be set to either 5 or 10 L/min (turbo mode). For temperatures below 100 K the system automatically adjusts the flow to 10 L/min, for temperatures above 100 K a flow of 5L/min is sufficient to maintain the temperature within 0.1 K. The cold gas flow can be positioned in many different ways, from vertical to horizontal. Accurate alignment is being done using the three positioners at the support stand with the aid of a nozzle alignment tool.
		Ulrich Englich ue22@cornell.edu

Storage and backup

		Each data collection machine has a 2 TB RAID array attached.(/A1a, /F1a, /F2a). Data should be written to the RAID array if possible for best capacity and performance. Additional disks and a spare RAID array are available in case of emergencies, and should be kept clear in case their use is needed.
		Users are welcome to bring their own laptop or other computers to CHESS for data processing and backup. IP addresses can be set up easily with DHCP, and static addresses are also available.
		MacCHESS supports IEEE 1394 (FireWire) and USB 2.0 connections on Mac and Linux. These interfaces are also available on Windows machines supported by CHESS. The Macs (macmac in the computer room and tarmac at F1) also support FireWire 800 (IEEE 1394b) as does the Linux machine kaoline in the computer room.
		Data can be transferred from CHESS to your home lab over the network. CHESS/MacCHESS is connected to the Cornell campus network via gigabit ethernet. Transfer speed to your home lab will vary from case to case. CHESS has a firewall, so connections to CHESS from outside are difficult. Consult your staff scientist if incoming connections are necessary.
		Tape drives are still available; please contact MacCHESS in advance if you wish to use any of these tape formats: 8mm (Exabyte 8500), 4mm (DDS 1-4), DLT4000, Ultrium.
		For a more detailed description of data backup and transport, see Dave Schuller's web page on bringing your data home http://staff.chess.cornell.edu/~schuller/backup.html
		David Schuller djs63@cornell.edu

Current backup devices

Each beam line has an 8mm tape drive and a 4mm DAT tape drive. Additional 8mm and 4mm tape drives are located in the computer room, along with a DLT4000 drive (lowerdec) and an Ultrium drive (flightdec). Bring your own tapes. If you need extras, the CHESS stockroom carries 8mm tapes and DDS-1 and DDS-3 4mm tapes.

supported tape formats:

		capacity	transfer rate (uncompressed)
8mm	Exabyte 8500	5 GB	0.5 MB/s
4mm DAT	DDS-2	4 GB	<0.5 MB/s
	DDS-3	12 GB	1 MB/s
	DDS-4	20 GB	3 MB/s
DLT (Digital Linear Tape)	DLT 4000	20 GB	1.5 MB/s
	Ultrium	100 GB	16 MB/s

MacCHESS still has older drives which handle the Exabyte 8200 8mm and DDS-1 4mm formats, but these will be unsupported (i.e. if they break we may not fix them).

David Schuller djs63@cornell.edu

Last updated October, 2009