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Question about guide camera and image camera place

Started by fblue, 11/08/2011 08:43PM
Posted 11/08/2011 08:43PM | Edited 11/08/2011 08:44PM Opening Post
I have a question that has been bothering me concerning guide scope placement and the relationship with the imaging camera.

I use a piggy back guide scope and have made a drawing that shows the scale of the guide scope, image scope and the pivot for the RA axis.

It shows that the guide scope, being further from the pivot point, makes an arc during a move that is 57% longer or greater than that of the imaging scope. Though the degree of movement on the axis remains the same for each, the distance traveled in each scope path across the sky is very different.

So, does this mean that the guide scope sees 57% more relative movemment than the image scope? Or does it actually stay the same because they both move the same degrees during this movement?

If the guide scope sees more relative movement how does this effect corrections made when it moves say 1 arc sec as far as the imaging scope is concerned? Does it still mean that they are moving exactly the same amount?

Does the mean that the further the guide scope points from where the image scope points there is a greater difference in this movement, like paralax?

Just wondering whether the piggy back placement makes the guide camera see movement differently than the image camera due to this difference in the arc path of each?

Thanks,
Floyd


Attached Image:

fblue's attachment for post 54419

[SIZE="Large"][/SIZE][COLOR="Blue"][/COLOR] Floyd Blue grin
Amateur Imager
Posted 11/08/2011 11:44PM #1
The movement in degrees is what matters as long as you have no flexure between scopes and cameras the relative positions will remain the same.
Dale