de.lehmannet.om.util
Class OpticsUtil

java.lang.Object
  de.lehmannet.om.util.OpticsUtil

public class OpticsUtil
extends java.lang.Object

Simple calculations on eyepieces, scopes, cameras.

Since:

1.7

Author:

doergn@users.sourceforge.net

Constructor Summary

OpticsUtil()

Method Summary

static float	getActualFocalLength(IScope scope, ILens lens, float magnification) Calculates the actual focal length of an eyepiece used on a scope together with a lens (barlow or sharpley).
static float	getExitPupil(IScope scope) Calculates the exit pupil of a given scope
static float	getExitPupil(IScope scope, float eyepieceFL, ILens lens) Calculates the exit pupil of a given scope eyepiece lens combination.
static float	getMagnification(IScope scope, float eyepieceFL) Calculates the magnification of a eyepiece used at a given scope.
static float	getMagnification(IScope scope, float eyepieceFL, ILens lens) Calculates the magnification of a eyepiece used at a given scope, and a used lens (barlow or sharpley).
static Angle	getTrueFieldOfView(IScope scope, float eyepieceFL, IEyepiece eyepiece, ILens lens) Calculates the true field of view In case the scope has a fixed magnification and the true field of view was set, returns this true field of view In case the scope has a focal length set, the eyepieces apparent field of view is divided by the magnification (which is calculated (together with the eyepiece))

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

OpticsUtil

public OpticsUtil()

Method Detail

getExitPupil

public static float getExitPupil(IScope scope,
                                 float eyepieceFL,
                                 ILens lens)

Calculates the exit pupil of a given scope eyepiece lens combination.

Returns:

The exit pupil of this scope/eyepiece combination, or Float.NaN if no magnification could be accessed or calculated

getExitPupil

public static float getExitPupil(IScope scope)

Calculates the exit pupil of a given scope

Returns:

The exit pupil of this scope, or Float.NaN if no magnification could be accessed

getTrueFieldOfView

public static Angle getTrueFieldOfView(IScope scope,
                                       float eyepieceFL,
                                       IEyepiece eyepiece,
                                       ILens lens)

Calculates the true field of view In case the scope has a fixed magnification and the true field of view was set, returns this true field of view In case the scope has a focal length set, the eyepieces apparent field of view is divided by the magnification (which is calculated (together with the eyepiece))

Parameters:

scope - A scope with fixed or variable magnification

eyepieceFL - Eyepiece focal length which was used

eyepiece - The eyepiece used

lens - Lens used (can be null)

Returns:

The true field of view or null on case it could not be calculated

getMagnification

public static float getMagnification(IScope scope,
                                     float eyepieceFL)

Calculates the magnification of a eyepiece used at a given scope.

Returns:

The magnification or Float.NaN if one of both parameters was NULL

getMagnification

public static float getMagnification(IScope scope,
                                     float eyepieceFL,
                                     ILens lens)

Calculates the magnification of a eyepiece used at a given scope, and a used lens (barlow or sharpley).

Parameters:

scope - The scope used (shouldn't have fixed magnification :-) )

eyepieceFL - The eyepiece focal length used

lens - The lens used (can be null if no lens was used)

Returns:

The magnification or Float.NaN if one of required parameters was NULL

getActualFocalLength

public static float getActualFocalLength(IScope scope,
                                         ILens lens,
                                         float magnification)

Calculates the actual focal length of an eyepiece used on a scope together with a lens (barlow or sharpley).
This method is used to get the actual focal length used in case an zoom eyepiece was used for an observation.

Parameters:

scope - The scope used (must not have fixed magnification )

lens - The lens used (can be null if no lens was used)

magnification - The magnification of the observation

Returns:

The actual focal length of the (zoom-)eyepiece used for that observation or Float.NaN if one of required parameters was NULL