Re: [ccp4bb] am I doing this right?

2021-10-26 Thread Marin van Heel
also an easy-to-find Youtube lecture on the issue by "marin van heel"). Cheers, Marin On Tue, Oct 26, 2021 at 3:58 AM Jacob Keller wrote: > Hi All, > > haven't been following CCP4BB for a while, then I come back to this juicy > Holtonian thread! > > Sorry for being m

[ccp4bb] Information, Resolution, FSC, ... All you ever wanted to know!

2020-09-23 Thread Marin van Heel
is enough to get a gist of the port of the matter. More than just two pennies worth (we hope), Cheers Marin (PS: we have applied for the necessary patents...) https://arxiv.org/abs/2009.03223 Google "arXiv" for "Information: to Harvest, to Have and to Hold" by: Marin van Heel

Re: [ccp4bb] [ccpem] Averaging data for gain correction

2020-09-14 Thread Marin van Heel
One more remark on the camera correction issue... The camera correction does actually matter quite a bit, especially where it concerns the movie alignments in the early phases of processing, as Tanaka mentioned too. What I want to point out here is that the effect of the camera correction needs

Re: [ccp4bb] [ccpem] Refinements against DeepEMhancer maps

2020-09-11 Thread Marin van Heel
Dear Wout, A suggestion from the inventor of the FRC/FSC: please read the discussions on using non-linear refinement procedures to optimise linear metrics beyond their defined validity range in: "Information: to Harvest, to Have and to Hold", by Marin van Heel & Michael Schatz. (htt

Re: [ccp4bb] Which resolution?

2020-02-27 Thread Marin van Heel
lved > in the > discussion, which is exactly the opposite of what a thread on a > scientific > bulletin board should be doing. > > > With best wishes, > > Gerard. > > -- > On Sun, Feb 23, 2020 at 08:15:34AM -0300, Marin van Heel wrote: >

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

2020-02-23 Thread Marin van Heel
So why am I not > using the 1/2-bit criterion in my own work? While numerically it behaves > well at most resolution ranges, I was not convinced by Marin's derivation > in 2005. Philosophically though, I think he's right - we should aim for FSC > thresholds that are more robust to the

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

2020-02-18 Thread Marin van Heel
> reading of the paper would reveal to you this much. > > Regards, > Pawel > > On Feb 16, 2020, at 10:38 AM, Marin van Heel > wrote: > >  > > * EXTERNAL EMAIL * > Dear Pawel and All others > > This 2010 review is - unfortunately - lar

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

2020-02-18 Thread Marin van Heel
ed 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 some very approximat

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

2020-02-17 Thread Marin van Heel
Dear Colin Great that you mention the Rose equation and its consequences for cryo-EM! I have actually written a paper on that topic some 40 years ago [Marin van Heel: Detection of object in quantum-noise limited images. Ultramicroscopy 8 (1982) 331-342]. I honestly have not thought about

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

2020-02-17 Thread Marin van Heel
issue alone…* *Marin van Heel, CNPEM/LNNano, Campinas, Brazil * On Sun, Feb 16, 2020 at 6:51 PM Petrus Zwart wrote: > 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

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

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

2020-02-12 Thread Marin van Heel
ov/pubmed/30198894 which is sort of along > similar lines of what you are hinting here. > Pavel > > On Wed, Feb 12, 2020 at 3:07 PM Marin van Heel < > 057a89ab08a1-dmarc-requ...@jiscmail.ac.uk> wrote: > >> Hi Tim, >> Good to hear from you! No longer at PSI??

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

2020-02-12 Thread Marin van Heel
an arbitrary number of > random re-orientations of such a helix, refine, and calculate the > variation in > position and rotation. > > This would reflect my understanding of resolution, much more than any > statistical descriptor. > > Best regards, > Tim > > On Wednesday, February

Re: [ccp4bb] Purchasing slides with diffraction gratings for teaching diffraction

2019-03-05 Thread Marin van Heel
Dear Pietro I have used many different gratings for the purpose over many years... Ones that I found very rewarding are writeable CDs and DVDs. They often come in a pack "protected" by a empty CD / DVD matrix hat is only plastic with grooves and no silver (or whatever the shiny recording material

Re: [ccp4bb] 2019 New Year’s resolutions of a cryo-EM newbie

2019-01-02 Thread Marin van Heel
Hello Jacob I know it was a bit of a cynical joke and I know it does hurt ... After all my mother's Ellis Island records are dated 1923. Our last family reunion was 15 years ago in Illinois and Missouri. My Mid-West raised uncle was torpedoed off the coast of Cape Canaveral in 1942 transporting

[ccp4bb] Position Available: HPC and Data-Processing Specialist (Campinas, Brazil)

2018-07-24 Thread Marin van Heel
142376” == Cheers Marin -- ==     Prof Dr Ir Marin van Heel     Laboratório Nacional de Nanotecnologia - LNNano     CNPEM/LNNano, Campinas, Brazil     tel:    +55-19-3518-2316   Skype:  Marin.van.Heel     email:  marin.vanheel(A_T)gma