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I have point data along lines shown in picture by black color. I made a grid by inverse distance method in QGIS. Maybe the result is not that appealing to eye or something (especially when eye is used to Oasis montaj minimum curvature grids).

Do you have any hints how to make my grid in QGIS looking more like that in Oasis.

I am not an expert on grid algorithms so maybe inverse distance is not even the best choice here but QGIS does not offer minimum curvature.

EDIT NOTE: Added new example dataset to demonstrate difference between QGIS and Oasis montaj grids.

Picture 1. QGIS grid (inverse distance) Picture 2. Oasis montaj grid (minimum curvature) Picture 3. Original data

Data is supposedly gravimetric data from a mine site.QGIS inverse distance

Oasis montaj minimum curvature

Original data

Estiivan
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    What does "look nice" mean? Can you point to some example of "nice looking" grid outputs? Does this map not reflect the data? What do you want to do with the grid when you've made it? – Spacedman May 31 '19 at 07:26
  • I attached a QGIS and Oasis montaj grids from same data. What I mean with nice looking is Oasis montaj grid with minimum curvature. QGIS does not offer miminum curvature so I used inverse distance but I don't think result is that good. For example, one can clearly see original lines. Secondly, I didn't find a nice colour palette like in Oasis. – Estiivan May 31 '19 at 09:25
  • You can build your own palette with QGIS. This tutorial deals with somehow similar data that you have https://www.qgistutorials.com/en/docs/interpolating_point_data.html. There is no Interpolation plugin for QGIS 3 but there seems to be Interpolation - TIN Interpolation in the standard processing toolbox. It might be worth trying. – user30184 May 31 '19 at 09:49
  • Multilevel B-Spline Interpolation – Kazuhito May 31 '19 at 10:50
  • I don't get this TIN interpolation. It does not ask what attribute in attribute table I am making the heatmap from. For me it seems that it only makes map from points themselves: how densely points are distributed. – Estiivan May 31 '19 at 12:07

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I have used Geosoft for working with Magnetic data a lot and the grid interpolation in QGIS leaves a lot to be desired. I have recently been playing around with it again and can offer a few tips.

  1. Set the color palette to something like this,

    enter image description here

  2. Remove NODATA. This is best done in the style tab

    enter image description here

  3. Cumulative Cut Stretch. This will style your image so the High's and Low's are more pronounced.

    enter image description here

  4. Create the raster with SAGA. I'm not sure what is wrong with the GDAL_Grid tool, but it does a terrible job of interpolating. However, Saga in QGIS Processing Toolbox does a great job. I personally like the Multilevel B-Spline Interpolation tool.

cndnflyr
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