August 2017

The July Photo Challenge was Up In The Air and the winners are:

1st Place Chris L   2nd Place Erick  
 Chris L  Erick
   
3rd Place Doug   3rd Place Phil  
 Doug  Phil
   
3rd Place Trish   4th Place Cheryl  
 Trish  Cheryl
   
4th Place Peggy  
 Peggy
 

 Link to the rest of this months photos

August’s topic is (Summer Golden Hour).

The regular monthly meeting is Thursday, August 24th 6:30pm at the Festival Foods Community Room.


 

July 2017

The June Photo Challenge was Windows or Doors and the winners are:

1st Place Phil 2nd Place Erick 
 Phil  Erick
   
3rd Place Doug   3rd Place Ron  
 Doug  Ron
3rd Place Cheryl   3rd Place Chris V  
 Cheryl  Chris V
4th Place Marlene   4th Place kathy  
 Marlene  Kathy
4th Place Robin  
 Robin

 Link to the rest of this months photos

July’s topic is (Up in the air).

The regular monthly meeting is Thursday, July 27th 6:30pm at the Festival Foods Community Room.


 

Astrophotography Focus Mask

The Bahtinov mask is a device used to focus small astronomical telescopes accurately. It was invented by Russian amateur astrophotographer Pavel Bahtinov in 2005. The telescope (or camera) is pointed at a bright star, and a mask is placed in front of the telescope’s objective (e.g. primary mirror) or the camera lens. You can generate one from Astrojargon 

Simulation_of_a_bahtinov_mask_diffraction_pattern_when_focusing.gif

Simulation of a bahtinov mask diffraction pattern when focusing

The mask consists of three separate grids, positioned in such a way that the grids produce three angled diffraction spikes at the focal plane of the instrument for each bright image element. As the instrument’s focus is changed, the central spike appears to move from one side of the star to the other. In reality, all three spikes move, but the central spike moves in the opposite direction to the two spikes forming the “X”. Optimal focus is achieved when the middle spike is centered between the other two spikes. 

From Wikipedia

 

 

 


Challenge Winners

Our Next Meeting

Time: 6:30 P.M.
Date: Aug 24th, 2017
Location: Festival Foods 3207 80th Street

Photo Challenge: Golden hour
Topic: