Here is a short report on the APM TS OAG that I just tried to use.
OK! I went out last night to do testing with the APM TS OAG. I used this unit due to its thin design of 9mm, which I needed to be able to use my TV reducer and meet its mounting restrictions for distance to CCD Chip. Unfortunately, the stem with the prism and guide camera mount, was too short when it was adjusted for focus. The prism was withdrawn from almost all the light cone and what it did intercept was badly distorted.
So, this will not allow me to use this OAG and makes it likely that no OAG will let me use my reducer with any configuration that is available, or that I can find anyway.
I have decided to attack the Flexure directly and am ordering ADM adjustable rings for Losmandy, which I have a dovetail to use. A 125mm set and a single 75mm. The 125mm set will work normally, with each mounted as far apart as possible. The third 75mm ring will mount on the focuser draw tube and will clamp on the draw tube after focusing. This will hold the entire scope and camera very rigid. I did not think of this, another fellow came up with the idea and it seems to work very well. Others I have talked to stated the third ring cured all the flexure issues for their systems when used with a good set of guiding rings.
If this does not cure all of the Flexure, this will indicate that there is sag in the 2" Televue focuser. I do not think that this is the case, but if it is then I may have to resort to replacing it with a 2.5" unit for more weight capacity.
I really wish the OAG had worked for me, it would have made things a lot easier in many ways. I think that with some other setups it would have worked fine, but with the 56mm limit on space and the short focal distance require for the guide camera, it just was not to be.
Probably will sell the OAG or just put it away for a future use where I did not have this distance issue, then it should be fine.
Just thought I would share this information with you all, so you could learn from my experience.
OK! I went out last night to do testing with the APM TS OAG. I used this unit due to its thin design of 9mm, which I needed to be able to use my TV reducer and meet its mounting restrictions for distance to CCD Chip. Unfortunately, the stem with the prism and guide camera mount, was too short when it was adjusted for focus. The prism was withdrawn from almost all the light cone and what it did intercept was badly distorted.
So, this will not allow me to use this OAG and makes it likely that no OAG will let me use my reducer with any configuration that is available, or that I can find anyway.
I have decided to attack the Flexure directly and am ordering ADM adjustable rings for Losmandy, which I have a dovetail to use. A 125mm set and a single 75mm. The 125mm set will work normally, with each mounted as far apart as possible. The third 75mm ring will mount on the focuser draw tube and will clamp on the draw tube after focusing. This will hold the entire scope and camera very rigid. I did not think of this, another fellow came up with the idea and it seems to work very well. Others I have talked to stated the third ring cured all the flexure issues for their systems when used with a good set of guiding rings.
If this does not cure all of the Flexure, this will indicate that there is sag in the 2" Televue focuser. I do not think that this is the case, but if it is then I may have to resort to replacing it with a 2.5" unit for more weight capacity.
I really wish the OAG had worked for me, it would have made things a lot easier in many ways. I think that with some other setups it would have worked fine, but with the 56mm limit on space and the short focal distance require for the guide camera, it just was not to be.
Probably will sell the OAG or just put it away for a future use where I did not have this distance issue, then it should be fine.
Just thought I would share this information with you all, so you could learn from my experience.
[SIZE="Large"][/SIZE][COLOR="Blue"][/COLOR] Floyd Blue
Amateur Imager
