In 2008, I bought a Hoya 720nm infrared filter. Back then, I had seen some funky photos on the internet and when I went to a photography store and saw the filter, I had to buy it! The first pictures with it were really disappointing: the filter in front of the sensor does a pretty good job in keeping the infrared out. So, the filter went into the cabinet.
Finally, in 2016, I modified my trusty EOS 350D and removed the IR-blocking-filter in front of the sensor. However, even then, I took only a few attempts in IR photography, especially as it was not that easy to take pictures with the 350D: It has no live-view and the autofocus and light metering does not work properly with the IR filter on the lens. Thus, everything is on manual... Furthermore, you get funky reflections with certain lenses (between filter and front-lens) and the sharpness of the photos was not that good.
There was, however, a solution for the sharpness issue. In 2016, I did not replaced the IR-blocking-filter by a glass plate. That was a big mistake. The autofocus system is designed to work with this glass plate in between, thus, if it is removed, the lens system is way out of focus! I finally inserted the glass May 2025 and since then I got again more interested in IR photography and even bought a used 10-22mm lens for wide-angle shots. Have a look at the photos - you can clearly see the difference of the out-of-focus ones towards the new ones!
With the high ISO you can do with modern cameras, it is somewhat possible to do it without the sensor filter removal. Some pictures were taken with my normal camera, but with long exposure.
All pictures were post-processed in darktable. You can notice that I try to put an artistic, rather than realistic touch to the photos. (But what is realistic on those pictures any ways!?)
Because I take most IR photos with the 350D, the quality is not that amazing (Native resolution 3474×2313!). Nevertheless, darktable does a good job in lens debluring.