Eye sight differences when viewing through telescope

[Naemeth]

wow, does this mean when you take a photo of a DSO it is out of focus for the rest of the family?

It just means at a fixed eye-photo distance, x, it will be out of focus for some, and in focus for others.

[whooshbang]

It just means at a fixed eye-photo distance, x, it will be out of focus for some, and in focus for others.

hehe, indeed. but if a person with bad eyesight and glasses/contact lenses removed were to manually focus a camera, take a photograph and print.... would that final print be out of focus when said person pops their glasses back on?

[Naemeth]

hehe, indeed. but if a person with bad eyesight and glasses/contact lenses removed were to manually focus a camera, take a photograph and print.... would that final print be out of focus when said person pops their glasses back on?

No. The point of perfect focus for the camera and telescope is fixed depending on the telescope's focal length, the sensor size etc. and not on the eyesight of the person using it. A photograph, or anything we see is seen through something not perfect, an eye, so we all focus things at different lengths from the object.

Does that make sense?

[VigdisVZ]

With that being said, if you want real focus for AP, a focus motor connected to ASCOM and something like Maxim DL is the only way to achieve max focus and automaticly refocus as temperature alters your optic train. It can focus way better than any optical method. Because mathematics.

[whooshbang]

No. The point of perfect focus for the camera and telescope is fixed depending on the telescope's focal length, the sensor size etc. and not on the eyesight of the person using it. A photograph, or anything we see is seen through something not perfect, an eye, so we all focus things at different lengths from the object.

Does that make sense?

it makes perfect sense but isn't a telescope focal length adjusted to achieve perfect focus by winding the focus tube in or out. therefore not entirely fixed ?

[Naemeth]

it makes perfect sense but isn't a telescope focal length adjusted to achieve perfect focus by winding the focus tube in or out. therefore not entirely fixed ?

I meant that the relative position of the focuser and the camera is fixed for perfect focus.

i.e. The Camera needs to be 50mm outwards for perfect focus. This focal length would be fixed for a certain camera.