BioXTAS RAW - IFT and P(r) functions using GNOM

This tutorial video teaches you how to do an indirect Fourier transform to get the pair distance distribution function (P(r)) using GNOM in BioXTAS RAW for small angle x-ray scattering (SAXS) data. It goes through the tutorial described here:
bioxtas-raw.re...
The tutorial assumes a basic working knowledge of processing scattering profiles in RAW, including loading, saving, and doing Guinier fits. It also requires a separate installation of the ATSAS package, available here:
www.embl-hambu...
More tutorial videos are available here:
• BioXTAS RAW Tutorials
BioXTAS RAW is a GUI based, free, open-source Python program for reduction and analysis of small-angle X-ray solution scattering (SAXS) data. The software is designed for biological SAXS data. It is available on windows, macOS (and OS X), and linux. It provides an alternative to closed source programs such as Primus and Scatter for primary data analysis. Because it can calibrate, mask, and integrate images it also provides an alternative to synchrotron beamline pipelines that scientists can install on their own computers and use both at home and at the beamline.
The software enables: creation of 1D scattering profiles from 2D detector images, standard data operations such as averaging and subtraction, analysis of radius of gyration (Rg) and molecular weight, and advanced analysis using GNOM and DAMMIF as well as electron density reconstructions using DENSS. It also allows easy processing of inline SEC-SAXS data and data deconvolution using the evolving factor analysis (EFA) method.
Learn more about RAW here:
bioxtas-raw.re...

[@graderc8868]

I was just wondering why it's important to cut the qmax at 8/Rg (and are you using the guinier Rg?) I'm new to processing SAXS data, do you recommend any sources for understanding basics and terminology (such as Dmax, Rg, etc)? My RAW doesnt have that Q box to check, so can I manually calculate qmax and change it in that qmax box at the top?

[@jessehopkins7947]

Cutting the P(r) function is important for bead model reconstructions. Higher q data starts to include information from things, like the hydration layer or intra-molecular voids, that can't be well modeled by the bead models. Including that data can lead to bad models.
You might check out the SAXS tutorials on the RAW website for more information.
bioxtas-raw.readthedocs.io/en/latest/saxs_tutorial.html
There's also a lot of good review articles available (and several recent books).
If you don't have the truncate q box, you should update the version of RAW you're using. But yes, you can manually calculate and change it.

[@graderc8868]

@@jessehopkins7947 Thank you!!