Focal Reducers????

Need to know about how to work that new mount or scope? Got tips on how to make it easier?

Re: Focal Reducers????

Postby Aardvark » Sat Jan 12, 2013 7:11 pm

The focal reducer is an add on , essentialy to give your scope/camera combination a wider field of view. With a DSLR and an 80mm refractor you will have a wide field of view. If you take images with your setup at the moment you will notice 'egg shaped' stars at the edges and corners of image. These are seen because the imaging chip is a flat sensor, unlike the retina which is concave. To overcome this you need to add an additional lens to 'correct' the edges of the image, these are known as 'field flatteners'. Now it must be a quirk of the optics (and I've little knowledge on that) but it would seem that you cannot produce a flattener without 'some' focal reduction and vice versa. Or if you could then these would be very expensive items.

On the other hand for the smaller webcam chips the 0.5 focal reducer makes them much more usable, and with the chip being smaller it does not capture the image to the edge of the 'light cone' and so is less likely to see the area which needs 'correcting'.

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Re: Focal Reducers????

Postby paraman » Sat Jan 12, 2013 9:03 pm

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Re: Focal Reducers????

Postby broady67 » Wed Jan 30, 2013 11:00 am

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Re: Focal Reducers????

Postby julian489289 » Sat Mar 09, 2013 10:30 pm

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Re: Focal Reducers????

Postby Edlen » Sat Mar 09, 2013 11:07 pm

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Re: Focal Reducers????

Postby julian489289 » Sun Mar 10, 2013 12:05 am

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Re: Focal Reducers????

Postby Edlen » Sun Mar 10, 2013 3:26 pm

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Re: Focal Reducers????

Postby Edlen » Sun Mar 10, 2013 3:35 pm

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Re: Focal Reducers????

Postby julian489289 » Sun Mar 10, 2013 9:54 pm

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Re: Focal Reducers????

Postby galactic_eagle631 » Fri Sep 20, 2013 6:46 am

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