|
|
Post by jonscheuler on Feb 26, 2012 0:19:53 GMT -5
 Just had 1st light of crescent moon and Jupiter with 4 moons strung vertically in near center alignment usinf a 150MM F8 istart achromat i installed as a replacement lens on an existing tube assembly - original manuf unknown. This was impressive. I need to cut off an inch or so of the tube to get the focal range I want, but this was the best i've seen yet. Thanks for the care in the creation of the lens, it shows. I'll include some picts. I made the adapter ring (counter-cell) out of a 9" diameter-3" thich section of 6061 aluminum bar stock - plunge cut a plug from the center and bored to the sizes required from there, only a couple of hours on the lathe after the center plug was cut out, the adapter ring almost does the cell justice - it will look as good as the functionality is when it's completed. The best use I've had yet of my shop, this project is turning out Awsome. I'm sort of excited, still shivering from the cold, but extremely pleased of the image quality - I was able to step down to about 10 mm on a 9 to 18mm Zoom lens, an also had 1st light on the 2" lens I've started to collect for this scope. I live in the middle of Kansas City Kansas, with street light and an incoming front tonight, and was viewing through the trees that surround my house, If I ever slow down enought from the excitement of the clarity of the images, I'll sleep with the pleasurable feeling of extreme contenment. Thanks again, this is going to be a very nice telescope. 
|
|
|
|
Post by Watcher3 on Feb 26, 2012 1:03:50 GMT -5
Sweeeeet! Can't wait to see some pics of the work you did. Any idea if the original scope was a Synta variant? If it was, there are probably a bunch of people that would be interested in your countercell design. Welcome aboard, and keep the reports coming. Great to have you here.  Joe |
|
|
|
Post by jonscheuler on Feb 26, 2012 1:32:25 GMT -5
So - this is an active place, I was begining to wonder as I noticed a lot of the dates are older. I'll take some picts, since I'll be disassembling the scope to cut the tube, and do a total colimation when I put it back together. I will take a couple of "before" picts, as I get started. I don't have any on this computer, and it's late enough that I don't want to start up the others tonight. I'm fairly shure the original is a sinta-variant, but not positive. there were no markings of any kind. The original lens cell is a poly-cast affair - fairly substantial, but the lenses had been removed at one time or another and there is evidence of damage from mold as well as some scratching from the lenes rubbing together. The spacer tabs were missing, but I was able to figure out what I needed to get it operational, only took a few tries, but I had to space the lenses farther apart than I wanted when I found them touching in the center. There was about an Inch of miore in the center and the stars were totally disappearing due to that. Not much abberation (chromatic) around the sides, but that got fairly bad by the time I got the center to clear. And the finger prints between the lenses showed up after cleaning the dust out with the worst of the mold. Not a terrible ebay buy, but not really useable either. I'll get to work on it tomorrow. After getting to see through it tonight - it's all downhill from here. I'll go ahead and take some pictures tonight of the "before condition", and of the old cell.
|
|
|
|
Post by Ales - iStar Optical on Feb 26, 2012 6:59:42 GMT -5
An ACTIVE place indeed!... and WELCOME to the club!!
cheers,
Ales
|
|
|
|
Post by borispider on Feb 26, 2012 10:41:59 GMT -5
Great report Jon and Welcome.
Glad it's all working out. I might have to look into
the ebay junk scopes for a tube source. Never thought of that.
|
|
|
|
Post by jonscheuler on Feb 27, 2012 22:03:16 GMT -5
I'll post more in the Istar ATM Area. I got rid of the springs - not needed. I'll use blue locktight instead. Attachments:
|
|
Just had 1st light of crescent moon and Jupiter with 4 moons strung vertically in near center alignment usinf a 150MM F8 istart achromat i installed as a replacement lens on an existing tube assembly - original manuf unknown. This was impressive. I need to cut off an inch or so of the tube to get the focal range I want, but this was the best i've seen yet. Thanks for the care in the creation of the lens, it shows. I'll include some picts. I made the adapter ring (counter-cell) out of a 9" diameter-3" thich section of 6061 aluminum bar stock - plunge cut a plug from the center and bored to the sizes required from there, only a couple of hours on the lathe after the center plug was cut out, the adapter ring almost does the cell justice - it will look as good as the functionality is when it's completed. The best use I've had yet of my shop, this project is turning out Awsome. I'm sort of excited, still shivering from the cold, but extremely pleased of the image quality - I was able to step down to about 10 mm on a 9 to 18mm Zoom lens, an also had 1st light on the 2" lens I've started to collect for this scope. I live in the middle of Kansas City Kansas, with street light and an incoming front tonight, and was viewing through the trees that surround my house, If I ever slow down enought from the excitement of the clarity of the images, I'll sleep with the pleasurable feeling of extreme contenment. Thanks again, this is going to be a very nice telescope. 
