This section is mostly astronomical and photographic information in the form of Excel workbooks containing calculation models.




Astronomical & Astrophotographic


Scope_Astro_and_B_Values.xls - This Excel workbook is a reasonably comprehensive model for telescope capabilities, astrophotography (including image sizes, resolutions and coverage) and the use of B values in simple astrophotography.  For those not familiar with B values, they are brightness values derived from experimental exposures on a variety of astronomical objects, both discrete and extended.  I believe they were first put into print by Michael Covington, but regardless, they provide an easy model by which to gauge exposure at particular ISO and aperture.  This sheet contains the primary example objects.  For those who wish to extend the use of B values, there is also a second worksheet containing an extended list of B values and exposures.


Astro_Exp_at_B_Value.xls - This Excel workbook shows complete aperture and shutter speeds for a range of B values at ISO 100 through to ISO 16000.  This should be enough for anyone to work with.


Collimation_Fast_Newtonian.doc - This Word document corrects the practise of collimation of fast Newtonians.  There are lot’s of standard works around describing collimation of clasical Newtonian telescopes, but rarely do they take into account the faster instruments whre the optimal configuration is an offset secondary.  Collimate these in a standard fashion and you’ll lose light!


Obs_log.xls - An Excel worksheet containing a simple but effective observation log.





EV_tables.xls - An Excel workbook containing a simple table of EV (exposure values) and corresponding aperture/shutter speed combinations.


Hyperfocal_and_shooting_tables.xls - This Excel workbook contains hyperfocal distance tables for a range of focal lengths and apertures for both 35mm cameras and 11.7 chip sizes too (such as those found in a number of digital compact cameras).  This information is also presented with near DOF information too (far DOF is always infinity).  Remember that for compact cameras, you need to use the real focal length of the lens at a particular zoom rather than the 35mm equivalent!  This worksheet also contains panorama shooting tables for 35mm cameras and compacts (landscape and portrait) for accurate creation of stitched panoramas.





Links to be added

All Photos are copyright J W Roger King or Penny J Hayward