We are a long way now from the days where we all shot black and white film. Colour was too expensive, and also too complex to process and print for most of us. We are even further from the 1910s, where some local authorities added extra rates to the water bills of amateurs who had a darkroom. Google will explain for those who don't know what "rates" were, but think Council Tax and you're there. But I digress. Now I shoot monochrome, or convert to monochrome, where I think the image is better for it, not as a matter of routine. Most of my images are in colour as a consequence, but sometime black and white is the more powerful medium.
For these shots I used the black and white setting of the Pentax K-1, and, just like the Q-S1 where I do the same, found that the results were quite to my liking. For the second two shots I used the same in-camera setting, but when resizing in Photoshop decided that sepia was the way to go. I suppose that shows the power of modern digital imaging, in that we can make some decisions later. But the real power of using the in-camera path to monochrome lies in the change of attitude and the different thought process that it enables. I often shoot different subjects if it's black and white from the start, looking for shapes and tones rather than colour. But whatever the process, it's something interesting to try.