• Posted on: 14 February 2019
  • By: tihomiry

HDR stands from High Dynamic Range. In short it is the number of tones that compose the image. The larger it is, the best capability we have to see details in the bright and dark regions of a scene. We mostly use it to prevent burning out bright objects and stars. Best way to do it is to take different exposure shots and stack them with DeepSkyStacker or similar software. Most high-end cameras has a build in function to do that. The disadvantage is that the resulting image is JPEG. This is also a quite power consuming process as using the camera image processor.
Below are single frame of Andromeda Galaxy with HDR OFF and ON. It is shot with Pnetax k-5. ISO 51200 and 30 seconds of exposure, untouched frame. You can easily see the greatest challenge of this object – bright core and faint outline. The core burn out is suppressed with the HDR function on.



This is a comparison of my not modified Pentax k5 DSLR and the same, but modified one without IR-cut filter.

Astrotracer is a great way to take advantage of the Pentax DSLR camera in-body shake reduction mechanism. It is available since Pentax k5 and track celestial bodies by moving the sensor. Here is what is it ablout:

Staying at my home inspires me to make some documentation of my experience. I got a dedicated drive for my astrophotos and start reorganize them by objects. Here is an article of the most recent process I use on my photos. Enjoy: )

For a few months from now Betelgeuse (Alpha Orion) dim so much, that it looks as bright as the stars in the Orion belt. This is not so disturbing and does not mean that cataclysmic events are happening with it.

For my last trip to the Rodopa mountain I decided to cross the limits and to target an object that is hard to believe that a non-professional equipment could catch.