Re: [ccp4bb] [3dem] Which resolution?

2020-03-12 Thread Petrus Zwart
---Original Message- > From: CCP4 bulletin board On Behalf Of Kay > Diederichs > Sent: Tuesday, March 10, 2020 2:48 AM > To: CCP4BB@JISCMAIL.AC.UK > Subject: Re: [ccp4bb] [3dem] Which resolution? > > I'd say that it depends on your state of knowledge, and on their I and

Re: [ccp4bb] [3dem] Which resolution?

2020-03-12 Thread Keller, Jacob
ensure such a mistake does not occur in the future. -Original Message- From: CCP4 bulletin board On Behalf Of Kay Diederichs Sent: Tuesday, March 10, 2020 2:48 AM To: CCP4BB@JISCMAIL.AC.UK Subject: Re: [ccp4bb] [3dem] Which resolution? I'd say that it depends on your state of knowledge

Re: [ccp4bb] [3dem] Which resolution?

2020-03-12 Thread Gergely Katona
wishes, Gergely -Original Message- From: CCP4 bulletin board On Behalf Of Bohdan Schneider Sent: March 12, 2020 11:05 To: CCP4BB@JISCMAIL.AC.UK Subject: Re: [ccp4bb] [3dem] Which resolution? Hello, B-factors actually do have a physical meaning which is at least to some extent reflected

Re: [ccp4bb] [3dem] Which resolution?

2020-03-12 Thread Bohdan Schneider
Hello, B-factors actually do have a physical meaning which is at least to some extent reflected by the crystal structures as refined. This can be demonstrated at higher resolution structures: when we created three tiers of structures, better than 1.9 Å, 1.9-2.4 Å, and 2.4-3.0 Å, structures

Re: [ccp4bb] [3dem] Which resolution?

2020-03-12 Thread Nave, Colin (DLSLtd,RAL,LSCI)
resting discussions Colin From: CCP4 bulletin board On Behalf Of Randy Read Sent: 09 March 2020 12:37 To: CCP4BB@JISCMAIL.AC.UK Subject: Re: [ccp4bb] [3dem] Which resolution? Hi Alexis, A brief summary of the relevant points in the paper that Pavel mentioned (https://journals.iuc

Re: [ccp4bb] [3dem] Which resolution?

2020-03-11 Thread Gerard DVD Kleywegt
If this is the case, why can't we use model B factors to validate our structure? I know some people are skeptical about this approach because B factors are refinable parameters. Rangana It is not clear to me exactly what you are asking. B factors _should_ be validated, precisely because

Re: [ccp4bb] [3dem] Which resolution?

2020-03-10 Thread Kay Diederichs
u want to see features with only a >>> small contrast above the surroundings then I think the half bit >>> threshold would be inappropriate. >>> >>> It would be good to see a clear message from the MX and EM >>> communities as to why an information conten

Re: [ccp4bb] [3dem] Which resolution?

2020-03-09 Thread James Holton
. We might then progress from the bronze age to the iron age. Regards Colin *From:*CCP4 bulletin board *On Behalf Of *Alexis Rohou *Sent:* 21 February 2020 16:35 *To:* CCP4BB@JISCMAIL.AC.UK *Subject:* Re: [ccp4bb] [3dem] Which resolution? Hi all, For those bewildered by Marin's insistenc

Re: [ccp4bb] [3dem] Which resolution?

2020-03-09 Thread James Holton
Well, in the example I made the individual atomic B factors, the Wilson B, and "true B-factor" were all the same thing.  Keeps it simple. But to be clear, yes: the B factors at the end of refinement are not the "true B-factors", they are our best estimation of them.  Given that no protein

Re: [ccp4bb] [3dem] Which resolution?

2020-03-09 Thread Randy Read
> > > > It would be good to see a clear message from the MX and EM communities as to > why an information content threshold of ½ a bit is generally appropriate for > these techniques and an acknowledgement that this threshold is > technique/problem dependent. > >

Re: [ccp4bb] [3dem] Which resolution?

2020-03-08 Thread Frank Von Delft
olin.n...@diamond.ac.uk<mailto:colin.n...@diamond.ac.uk> Sent: 17 February 2020 11:26 To: CCP4BB@JISCMAIL.AC.UK<mailto:CCP4BB@JISCMAIL.AC.UK> Subject: [ccp4bb] FW: [ccp4bb] [3dem] Which resolution? Dear all. Would it help to separate out the issue of the FSC from the value of

Re: [ccp4bb] [3dem] Which resolution?

2020-03-08 Thread Alexis Rohou
> > > > > > > *From:* CCP4 bulletin board *On Behalf Of *Alexis > Rohou > *Sent:* 21 February 2020 16:35 > *To:* CCP4BB@JISCMAIL.AC.UK > *Subject:* Re: [ccp4bb] [3dem] Which resolution? > > > > Hi all, > > > > For those bewildered by Marin's insi

Re: [ccp4bb] [3dem] Which resolution?

2020-03-08 Thread Dale Tronrud
Just a note: James Holton said "true B-factor" not "true B-factors". I believe he was talking about the overall B not the individual B's. Dale Tronrud On 3/8/2020 3:25 PM, Rangana Warshamanage wrote: > Sorry for not being clear enough. > If B-factors at the end of refinement are the "true

Re: [ccp4bb] [3dem] Which resolution?

2020-03-08 Thread Rangana Warshamanage
Sorry for not being clear enough. If B-factors at the end of refinement are the "true B-factors" then they represent a true property of data. They should be good enough to assess the model quality directly. This is what I meant by B factor validation. However, how far are the final B-factors

Re: [ccp4bb] [3dem] Which resolution?

2020-03-08 Thread Ethan A Merritt
On Sunday, 8 March 2020 01:08:32 PDT Rangana Warshamanage wrote: > "The best estimate we have of the "true" B factor is the model B factors > we get at the end of refinement, once everything is converged, after we > have done all the building we can. It is this "true B factor" that is a >

Re: [ccp4bb] [3dem] Which resolution?

2020-03-08 Thread Kay Diederichs
we can use model B factors to validate structures - see Analysis and validation of macromolecular B values R. C. Masmaliyeva and G. N. Murshudov Acta Cryst. (2019). D75, 505-518 https://doi.org/10.1107/S2059798319004807 HTH Kay On Sun, 8 Mar 2020 09:08:32 +, Rangana Warshamanage wrote:

Re: [ccp4bb] [3dem] Which resolution?

2020-03-08 Thread Rangana Warshamanage
"The best estimate we have of the "true" B factor is the model B factors we get at the end of refinement, once everything is converged, after we have done all the building we can. It is this "true B factor" that is a property of the data, not the model, " If this is the case, why can't we use

Re: [ccp4bb] [3dem] Which resolution?

2020-03-07 Thread Robert Stroud
James answer seems right, and make abject sense. -and makes sense by experience too.. Bob Robert Stroud str...@msg.ucsf.edu > On Mar 7, 2020, at 12:01 PM, James Holton wrote: > > Yes, that's right. Model B factors are fit to the data. That Boverall gets > added to all atomic B factors

Re: [ccp4bb] [3dem] Which resolution?

2020-03-07 Thread dusan turk
James, > On 7 Mar 2020, at 21:01, James Holton wrote: > > Yes, that's right. Model B factors are fit to the data. That Boverall gets > added to all atomic B factors in the model before the structure is written > out, yes? Almost true. It depends how the programs are written. In MAIN this

Re: [ccp4bb] [3dem] Which resolution?

2020-03-07 Thread James Holton
Yes, that's right.  Model B factors are fit to the data.  That Boverall gets added to all atomic B factors in the model before the structure is written out, yes? The best estimate we have of the "true" B factor is the model B factors we get at the end of refinement, once everything is

Re: [ccp4bb] [3dem] Which resolution?

2020-03-07 Thread dusan turk
James, The case you’ve chosen is not a good illustration of the relationship between atomic B and resolution. The problem is that during scaling of Fcalc to Fobs also B-factor difference between the two sets of numbers is minimized. In the simplest form with two constants Koverall and

Re: [ccp4bb] [3dem] Which resolution?

2020-03-06 Thread Pavel Afonine
tistically that a few > >>> non-background counts fell into the sum of all spot areas at 3.0 A. > >>> These are not the same thing. > >>> > >>> Don't get me wrong, including the weak high-resolution information > >>> makes the m

Re: [ccp4bb] [3dem] Which resolution?

2020-03-06 Thread James Holton
l resolution, could be “Is there significant information in the data at the required contrast and resolution?”. Then “Can one obtain this information at a dose below any radiation damage limit” Keep posting! Regards Colin *From:*James Holton *Sent:* 27 February 2020 01:14 *To:* CCP4BB@JISCMAIL.AC.

Re: [ccp4bb] [3dem] Which resolution?

2020-03-05 Thread Kay Diederichs
edge. The second one gives >> much greater Bijvoet differences despite the fact that the nominal >> resolution is the same. I doubt whether anyone doing this would be >> misled by this as they would examine the statistics for the Bijvoet >> differences instead. However, it

Re: [ccp4bb] [3dem] Which resolution?

2020-03-04 Thread James Holton
e age to the iron age. Regards Colin *From:*CCP4 bulletin board <mailto:CCP4BB@JISCMAIL.AC.UK> *On Behalf Of *Alexis Rohou *Sent:* 21 February 2020 16:35 *To:* CCP4BB@JISCMAIL.AC.UK <mailto:CCP4BB@JISCMAIL.AC.UK> *Subject:* Re: [ccp4bb] [3dem] Which resolution?

Re: [ccp4bb] [3dem] Which resolution?

2020-02-27 Thread Keller, Jacob
ique/problem dependent. We might then progress from the bronze age to the iron age. Regards Colin From: CCP4 bulletin board <mailto:CCP4BB@JISCMAIL.AC.UK> On Behalf Of Alexis Rohou Sent: 21 February 2020 16:35 To: CCP4BB@JISCMAIL.AC.UK<mailto:CCP4BB@JISCMAIL.AC.UK> Subject: Re:

Re: [ccp4bb] [3dem] Which resolution?

2020-02-27 Thread Nave, Colin (DLSLtd,RAL,LSCI)
To: CCP4BB@JISCMAIL.AC.UK Cc: Nave, Colin (DLSLtd,RAL,LSCI) Subject: Re: [ccp4bb] [3dem] Which resolution? In my opinion the threshold should be zero bits. Yes, this is where CC1/2 = 0 (or FSC = 0). If there is correlation then there is information, and why throw out information

Re: [ccp4bb] [3dem] Which resolution?

2020-02-26 Thread James Holton
ue/problem dependent. We might then progress from the bronze age to the iron age. Regards Colin *From:*CCP4 bulletin board *On Behalf Of *Alexis Rohou *Sent:* 21 February 2020 16:35 *To:* CCP4BB@JISCMAIL.AC.UK *Subject:* Re: [ccp4bb] [3dem] Which resolution? Hi all, For those bewilde

[ccp4bb] AW: [ccp4bb] [3dem] Which resolution?

2020-02-23 Thread Jon Hughes
absolutely. jon -Ursprüngliche Nachricht- Von: CCP4 bulletin board Im Auftrag von Gerard Bricogne Gesendet: Sonntag, 23. Februar 2020 20:42 An: CCP4BB@JISCMAIL.AC.UK Betreff: Re: [ccp4bb] [3dem] Which resolution? Gentlemen, Please consider for a moment that by such intemperate

Re: [ccp4bb] [3dem] Which resolution?

2020-02-23 Thread Andreas Förster
A very good point, Gerard, but maybe too late. It seems to me that a lot of microscopists have already given up this abundantly discussed question. They just call everything atomic resolution irrespective of whatever numerical value they arrive at by whatever means. All best. Andreas

Re: [ccp4bb] [3dem] Which resolution?

2020-02-23 Thread Gerard Bricogne
Gentlemen, Please consider for a moment that by such intemperate language and tone, you are making a topic of fundamental importance to both the MX and the EM communities into a no-go area. This cannot be good for anyone's reputation nor for the two fields in general. It has to be possible

Re: [ccp4bb] [3dem] Which resolution?

2020-02-23 Thread Marin van Heel
Hi Carlos Oscar and Jose-Maria, I choose to answer you guys first, because it will take little of my time to counter your criticism and because I have long since been less than amused by your published, ill-conceived criticism: “*Marin, I always suffer with your reference to sloppy statistics.

Re: [ccp4bb] [3dem] Which resolution?

2020-02-22 Thread Nave, Colin (DLSLtd,RAL,LSCI)
Subject: Re: [ccp4bb] [3dem] Which resolution? Hi all, For those bewildered by Marin's insistence that everyone's been messing up their stats since the bronze age, I'd like to offer what my understanding of the situation. More details in this thread from a few years ago on the exact same topic

Re: [ccp4bb] [3dem] Which resolution?

2020-02-21 Thread Alexis Rohou
Hi all, For those bewildered by Marin's insistence that everyone's been messing up their stats since the bronze age, I'd like to offer what my understanding of the situation. More details in this thread from a few years ago on the exact same topic:

Re: [ccp4bb] [3dem] Which resolution?

2020-02-20 Thread Nave, Colin (DLSLtd,RAL,LSCI)
at the 2019 CCP4 study weekend paper Regards Colin From: Randy Read Sent: 20 February 2020 11:45 To: Nave, Colin (DLSLtd,RAL,LSCI) Cc: CCP4BB@jiscmail.ac.uk Subject: Re: [ccp4bb] [3dem] Which resolution? Dear Colin, Over the last few years we've been implementing measures of information gain

Re: [ccp4bb] [3dem] Which resolution?

2020-02-20 Thread Randy Read
t;http://www.mt-archive.info/50/SciAm-1949-Weaver.pdf> > > Sorry for the long reply – but at least some of it was requested! > > Colin > > > > From: CCP4 bulletin board <mailto:CCP4BB@JISCMAIL.AC.UK>> On Behalf Of colin.n...@diamond.ac.uk > <mailto:coli

Re: [ccp4bb] [3dem] Which resolution?

2020-02-20 Thread Nave, Colin (DLSLtd,RAL,LSCI)
.AC.UK<mailto:CCP4BB@JISCMAIL.AC.UK> Subject: Re: [ccp4bb] [3dem] Which resolution? Hi All, How is the 'correct' resolution estimation related to the estimated error on some observed hydrogen bond length of interest, or an error on the estimated occupancy of a ligand or conformation or a

Re: [ccp4bb] [3dem] Which resolution?

2020-02-18 Thread Marin van Heel
Hi Pawel, We can indeed agree to disagree upon many basic things in life. We apparently disagree on the basic assumptions upon which you choose to build your science! What I am criticising is the very foundation you use to construct your science, namely the flawed Frank & Al-Ali (1975) formula

Re: [ccp4bb] FW: [ccp4bb] [3dem] Which resolution?

2020-02-18 Thread Marin van Heel
restricted lens aperture. > > > > Good debate though. > > > > Colin > > *From:* John R Helliwell > *Sent:* 17 February 2020 16:36 > *To:* Nave, Colin (DLSLtd,RAL,LSCI) > *Cc:* CCP4BB@JISCMAIL.AC.UK > *Subject:* Re: [ccp4bb] FW: [ccp4bb] [3dem] Whic

Re: [ccp4bb] FW: [ccp4bb] [3dem] Which resolution?

2020-02-17 Thread John R Helliwell
well > Sent: 17 February 2020 16:36 > To: Nave, Colin (DLSLtd,RAL,LSCI) > Cc: CCP4BB@JISCMAIL.AC.UK > Subject: Re: [ccp4bb] FW: [ccp4bb] [3dem] Which resolution? > > Hi Colin, > Neutrons are applied to the uranyl hydrides so as to make their scattering > lengths much more e

Re: [ccp4bb] FW: [ccp4bb] [3dem] Which resolution?

2020-02-17 Thread Marin van Heel
; FRC. If you can comment on this in your *Why-o-Why didactical crusade, I > might even register for a twitter account!* > > *Regards* > > *Colin* > > > > *From:* CCP4 bulletin board *On Behalf Of *Marin > van Heel > *Sent:* 17 February 2020 13:29

Re: [ccp4bb] FW: [ccp4bb] [3dem] Which resolution?

2020-02-17 Thread Nave, Colin (DLSLtd,RAL,LSCI)
Sent: 17 February 2020 16:36 To: Nave, Colin (DLSLtd,RAL,LSCI) Cc: CCP4BB@JISCMAIL.AC.UK Subject: Re: [ccp4bb] FW: [ccp4bb] [3dem] Which resolution? Hi Colin, Neutrons are applied to the uranyl hydrides so as to make their scattering lengths much more equal than with X-rays, and so side step

[ccp4bb] FW: [ccp4bb] [3dem] Which resolution?

2020-02-17 Thread colin.n...@diamond.ac.uk
C.UK>> On Behalf Of Marin van Heel Sent: 17 February 2020 13:29 To: CCP4BB@JISCMAIL.AC.UK<mailto:CCP4BB@JISCMAIL.AC.UK> Subject: Re: [ccp4bb] [3dem] Which resolution? Dear Petrus Zwart (and all other X-ray crystallographers and EM-ers) Resolution in the sense of the Abbe Diffraction Limit

Re: [ccp4bb] FW: [ccp4bb] [3dem] Which resolution?

2020-02-17 Thread John R Helliwell
uraged from applying some I/sigI type cut off. > > Cheers > Colin > > > > From: John R Helliwell > Sent: 17 February 2020 12:09 > To: Nave, Colin (DLSLtd,RAL,LSCI) > Subject: Re: [ccp4bb] FW: [ccp4bb] [3dem] Which resolution? > > Hi Colin, > I think th

Re: [ccp4bb] FW: [ccp4bb] [3dem] Which resolution?

2020-02-17 Thread colin.n...@diamond.ac.uk
: [ccp4bb] [3dem] Which resolution? Hi Colin, I think the physics of the imaging and the crystal structure analysis, respectively without and with Fourier termination ripples, are different. For the MX re Fourier series for two types of difference map see our contribution:- http://scripts.iucr.org/cgi

Re: [ccp4bb] [3dem] Which resolution?

2020-02-17 Thread Marin van Heel
Dear Petrus Zwart (and all other X-ray crystallographers and EM-ers) Resolution in the sense of the Abbe Diffraction Limit or the Rayleigh *Criterion are part of what we would now call the theory of linear systems, and are described by a “transfer function”. “Fourier Optics” covers the theory

[ccp4bb] FW: [ccp4bb] [3dem] Which resolution?

2020-02-17 Thread colin.n...@diamond.ac.uk
databases will simply search for the structure with the highest named resolution. It might be difficult to send these users to re-education camps. Regards Colin From: CCP4 bulletin board On Behalf Of Petrus Zwart Sent: 16 February 2020 21:50 To: CCP4BB@JISCMAIL.AC.UK Subject: Re: [ccp4bb] [3dem] Which

Re: [ccp4bb] [3dem] Which resolution?

2020-02-16 Thread Petrus Zwart
Hi All, How is the 'correct' resolution estimation related to the estimated error on some observed hydrogen bond length of interest, or an error on the estimated occupancy of a ligand or conformation or anything else that has structural significance? In crystallography, it isn't really (only in

Re: [ccp4bb] [3dem] Which resolution?

2020-02-16 Thread Marin van Heel
Dear Pawel and All others This 2010 review is - unfortunately - largely based on the flawed statistics I mentioned before, namely on the a priori assumption that the inner product of a signal vector and a noise vector are ZERO (an orthogonality assumption). The (Frank & Al-Ali 1975) paper