I had started compiling little things like this a while ago. I need to share it! I started categorizing them by what the effect on the image was, with the idea of eventually having a reference book.
Something like this:
The most important ones:
Thank you! Keep em coming!
I’ve created presets for those which I called (instance 0, instance 1, instance2).
When denoising high ISO pictures, I found that doing the following is sometimes quite efficient:
Use the bilateral denoise with radius set to the maximum, red and blue to the maximum (or close) and green to the minimum.
The red and blue channels are frequently more noisy than the green one, and using this parameters allow to smooth them without losing too much details.
Please note that this technique is inefficient if any denoising smooths the color before this module in the pipeline. For example, if you use denoise profile with wavelet in “color” mode, this technique will not give proper result.
Thus, when I use it, I smooth color noise later in the pipeline, with a second bilateral denoise module in “color” mode
Thank you Andreas, I forgot to add that one, yes I use that also—I saved it as a style. Another denoise triplet I saved as a style is:
Not sure where I got this, probably Harry again, but I named this style ‘Denoise Gentle’ as it removes some of the noise without turning the image into a watercolor. Play with it, I get good results, sometimes I increase or reduce the Equalizer mix to fine tune.
Thx - I love this and am learning so much!
The site https://www.multimedia4linux.de/ contains a lot of darktable material - tutorials, videos, plugins. Most of the texts are in German.
nice! i’m thinking we should maybe ship some of those with stock dt. presets can be a good starting point, source of inspiration and hands-on documentation.
One of Harry D’s presets that I frequently use. It does wonders for opening-up and providing texture to the deepest shadows. A very important tool in my processing.
Tone Mapping: Compression=1.66, Spacial=6%, Para Mask on ‘g’ with settings= 0 0 0 8 and Normal blend.
So many useful tricks here. Keep them coming!
Denoising ISO1600 on MFT (Probably ISO6400 on FF)
Hot Pixels - threshold 0.01 - strength 0.7
Demosaic method amaze - color smoothing five times - match greens disabled
This gives nice analog looking grain.
Thanks for sharing, David. Yes, it does do wonders! 
I do my rating/culling as chris describes. Works fine and fast. RAW files show the JPG preview if no processing was done so that’s fast.
I setup this Tone Mapping preset, but I’m not seeing much changes in the dark areas. I do confirm the mask is picking the very darkest parts of the picture. Maybe its because I’m working with jpg?
One more:
soft light illumination with bloom module.
this is the starting point:
I would like to draw even more attention to dimly lit houses on the horizon
So first I need to brighten up this local area (exposure module with drown mask):
Now I’m activating “bloom” module in “effects tab”, increasing size to 70% reducing threshold to about 25% and increasing strength to 70%.
blend - uniformly
blend mode - multiply:
Here is before and after:
One more before and after:
The values of bloom module, which I mentioned above, are of course adapted to the corresponding motif. Accordingly, they serve only as an orientation.
It is important to first illuminate the area of the image that you want to emphasize according to your own imagination and “bloom” module makes sure that this emphasization is smooth.
Hi Alan;
This preset will only effect the very darkest elements of your image .. (those values between 0 to 8 on the gray scale of 100). If you click on the mask display you will see exactly which area is being changed. The changes are also progressive so that the darker the element, the greater the change.
It is possible to change the 8 value to a higher number so as to effect a wider shadow scale. Tone Mapping can be a very aggressive function if used over wider areas so you should understand it better and use it with caution .... it is not a quick fix for underexposed shots.
If you are having under/over exposed problems sometimes using 'fusion' processing (in the base curve module) can assist.
darktable is designed primarily to be used with RAW camera data and not JPEG files that are already preprocessed and compressed within the camera. The use of the Tone Mapper on JPEG files may well not produce the designed results. If you are serious about getting the very best out of your personal skills and the camera's capability, you should really work in the RAW format.
Cheers;
David
Hi Alan;
This preset will only effect the very darkest elements of your image … (those values between 0 to 8 on the gray scale of 100). If you click on the mask display you will see exactly which area is being changed. The changes are also progressive so that the darker the element, the greater the change.
It is possible to change the 8 value to a higher number so as to effect a wider shadow scale. Tone Mapping can be a very aggressive function if used over wider areas so you should understand it better and use it with caution … it is not a quick fix for underexposed shots.
If you are having under/over exposed problems sometimes using ‘fusion’ processing (in the base curve module) can assist.
darktable is designed primarily to be used with RAW camera data and not JPEG files that are already preprocessed and compressed within the camera. The use of the Tone Mapper on JPEG files may well not produce the designed results. If you are serious about getting the very best out of your personal skills and the camera’s capability, you should really work in the RAW format.
Cheers;
David
Thank you! I love the softer vignetting. Here is my quickie attempt, before, after the technique, and fully edited (including applying Norman’s denoise trick above). 
IMG_3461.cr2.xmp (12.0 KB)
My current favorite trick to get postcard landscapes is to
Use three exposures in base curve sparingly to get a bit more detail if there is a lot of dynamic range
Apply a gentle base curve like the Leica preset because the next step adds contrast
Use the filmic tonemap operator with maxed or high detail. Set blend mode to multiply and reduce opacity to taste.
Enjoy very saturated postcard look.