Custom 4" Coma Correctors for the Dream Astrograph line and other select customers.


See images taken by a 16" f3.75 Dream Astrograph customer using the custom 4" coma corrector and 4" Off-Axis Guider that was designed specifically for Dream's 4" coma corrector, that has extended back-focus allowing OAG use before the filter.


The custom 4" coma corrector has an additional 20mm (82mm versus 62mm for the standard 3" and 4" coma correctors) of back focus. This will allow the use of the 4" Off-Axis Guider (OAG) prior to the filters.

The spot diagram to the left shows the quality of the custom 4" coma corrector in combination with the 24" f3.5 Dream Astrograph.

Note the RMS spot size never grows larger than 3 microns, even 26mm off-axis (52mm image circle)! This is the full field of a 1.5" (36mm) square CCD chip.

Click here to see the vignetting chart for the above combination. 


Click on the image to the left to see the custom 4" coma correctors.


The spot diagram to the right shows the quality of the custom 4" coma corrector on the 16" f3.75 Dream Astrograph.

Click here to see the vignetting chart for the above combination. 
 
 
 

Click on the small image below to see the matrix spot diagram, which shows chromatic performance of this corrector.


 

 
 


pricing, availability and specifications subject to change without notice