Focal Reducer Shootout ... coming soon.
Many people would like to know what differences there are in the many focal reducers that are out on the market.
This shootout will be very simple, and images will provide answers as to what one can expect by using these units in either a SCT 8 inch and or a 72MM refractor. all test targets will be of stars only, our interest is how much FOV are we getting and how bad are the edges , "coma. vignette or other aberrations..."
That being said , the test will be performed on the Double cluster in Perseus with the C8 (F10) , then with the AT72ED (F5). One shot at full focal length, then using the 3 or 4 reducers to compare. Also included will be the weight of each units, their FL, and anything i can find from the manufacturer.
The only test being done here is FOV and outer edges stars, whether the reducer is designed to correct or not is not the purpose here. Hope fully i will have all the right adapters to get the correct focal length of each reducer...
So enjoy this 2 -3 week project , let me know what you though of the tests. and what reducer is your favorite.
IMAGING: Here is the layout of the test. First a image at full F ratio of both scopes...Then.
H=Hirsch C=Celestron O=Optec M=Meade A=Antares (if Applicable)
1- C8+DSLR+FR/HCOM AT72ED+DSLR+FR/HCOM
2- C8+DSI PRO +FR/HCOM AT72ED + DSI PRO + FR/HCOM
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This shootout will be very simple, and images will provide answers as to what one can expect by using these units in either a SCT 8 inch and or a 72MM refractor. all test targets will be of stars only, our interest is how much FOV are we getting and how bad are the edges , "coma. vignette or other aberrations..."
That being said , the test will be performed on the Double cluster in Perseus with the C8 (F10) , then with the AT72ED (F5). One shot at full focal length, then using the 3 or 4 reducers to compare. Also included will be the weight of each units, their FL, and anything i can find from the manufacturer.
The only test being done here is FOV and outer edges stars, whether the reducer is designed to correct or not is not the purpose here. Hope fully i will have all the right adapters to get the correct focal length of each reducer...
So enjoy this 2 -3 week project , let me know what you though of the tests. and what reducer is your favorite.
IMAGING: Here is the layout of the test. First a image at full F ratio of both scopes...Then.
H=Hirsch C=Celestron O=Optec M=Meade A=Antares (if Applicable)
1- C8+DSLR+FR/HCOM AT72ED+DSLR+FR/HCOM
2- C8+DSI PRO +FR/HCOM AT72ED + DSI PRO + FR/HCOM
---------------------------------------------------------------------------------------------------------------------------------------------------
Simply put a Focal reducer does what it says , reducing the focal length of any given telescope which increases the FOV and the reduces the time it takes to image a DSO by X factor.
The faster the F/Ratio is, the smaller the cone of light becomes, hence the brighter the image.
See: Figure 1
more info by Wiki:
A telecompressor or focal reducer is an optical element which amateur astronomers use to reduce the focal length of a telescope.
Mainly used for astrophotography, the telecompressor gives a wider angle of view, a sharper picture, and reduces the exposure time needed [1]. These are useful when taking pictures of nearby large objects, such as nebulas. The effects and uses of the telecompressor are largely opposite to those of the teleconverter or barlow lens.
Click here for additional information:
The faster the F/Ratio is, the smaller the cone of light becomes, hence the brighter the image.
See: Figure 1
more info by Wiki:
A telecompressor or focal reducer is an optical element which amateur astronomers use to reduce the focal length of a telescope.
Mainly used for astrophotography, the telecompressor gives a wider angle of view, a sharper picture, and reduces the exposure time needed [1]. These are useful when taking pictures of nearby large objects, such as nebulas. The effects and uses of the telecompressor are largely opposite to those of the teleconverter or barlow lens.
Click here for additional information:
