- #1
Saladsamurai
- 3,020
- 7
I'll take any information, I just know that Russ and Turbo have helped me before.
Okay, here is the rundown: I have a really inexpensive ($150) Meade reflector telescope.
Here are the specs: 114 mm primary, F=1000mm, f/8.8
I am not quite sure what the F=1000mm, f/8.8 means.
Now, the telescope is a little strange in that it has some sort of 'lens' located in the focuser tube. Yes a lens. It is midway between where the eyepiece is inserted and where the focuser tube ends in the optical tube.
It serves as some sort of relay...or a way of allowing them to make the telescope shorter and more compact. (Russ, you may recall this)
I really feel like this lens is taking away from the viewing experience. I feel it worsens the telescopes optics.
I wouldn't mind experimenting with the scope. I have an extra Crayford style focuser lying around. I was thinking of removing the old 'relay' focuser', cutting a larger hole in the optical tube, and putting in the Crayford.
I am just not sure how this will change things. I am sure there will be some math involved, but I don't mind.
Will this change the focal length? What does that mean anyway? Will I need to Adjust how high the focuser assembly is from the optical tube? (I assume I will, though I can't exactly say why!) If so, how can I figure out how high?
I know this is a lengthy question and there are other astronomy sites where I could ask. But, I am convinced that I receive the best information here. And I am willing to expend the energy to learn how to figure these things out. I think this experiment will help me get familiar with the parts and workings of the telescope so that when I attempt to build one this summer I will at least know some basics.
Thanks
Okay, here is the rundown: I have a really inexpensive ($150) Meade reflector telescope.
Here are the specs: 114 mm primary, F=1000mm, f/8.8
I am not quite sure what the F=1000mm, f/8.8 means.
Now, the telescope is a little strange in that it has some sort of 'lens' located in the focuser tube. Yes a lens. It is midway between where the eyepiece is inserted and where the focuser tube ends in the optical tube.
It serves as some sort of relay...or a way of allowing them to make the telescope shorter and more compact. (Russ, you may recall this)
I really feel like this lens is taking away from the viewing experience. I feel it worsens the telescopes optics.
I wouldn't mind experimenting with the scope. I have an extra Crayford style focuser lying around. I was thinking of removing the old 'relay' focuser', cutting a larger hole in the optical tube, and putting in the Crayford.
I am just not sure how this will change things. I am sure there will be some math involved, but I don't mind.
Will this change the focal length? What does that mean anyway? Will I need to Adjust how high the focuser assembly is from the optical tube? (I assume I will, though I can't exactly say why!) If so, how can I figure out how high?
I know this is a lengthy question and there are other astronomy sites where I could ask. But, I am convinced that I receive the best information here. And I am willing to expend the energy to learn how to figure these things out. I think this experiment will help me get familiar with the parts and workings of the telescope so that when I attempt to build one this summer I will at least know some basics.
Thanks