Orion’s 100mm f/6 versus their 80mm ED OTA
Posted 01 November 2003 - 10:55 AM
They use the same tube size and have the same focal length beyond that they differ.
The 80mm ED OTA is $429, comes with no accessories and has a waiting list.
The 100mm OTA is $249 (I got mine off Orion’s clearance section for $211) and it comes with a collimating tool.
Here is another difference between the two; the 100mm has an adjustable lens cell the 80mm ED does not.
Here on the forum it was stated a retailer of the 80mm ED said he has had to adjust the focuser (since this is the only way to collimate it) on every one he has sold so far.
I was not looking for a travel scope but a light weight, rich field scope that was easy to setup (I have mine mounted on Orion’s AZ-3 mount) and with minimum cool down time for backyard use. The 100mm on the AZ-3 with 1.25” accessories weighs about 20 pounds.
Another alternative is Orion’s 120mm f/5 OTA for $319. I tried one but it was too heavy to use on the AZ-3 mount. I suggest an equatorial mount for it.
Of course, the 80mm ED should show less color on Jupiter but will it show more detail than the 100mm; probably not, especially in my average seeing conditions where I am kept below 120X as Jupiter begins to wash out (these were observations in my 90mm/1000mm Japanese made objective) at powers above 120X.
It would be interesting to compare the two; especially if the 100mm has a filter for the violet color (with most filters on the market the 100mm will still cost less than the 80mm ED).
I just wanted to present an alternative choice.
Posted 01 November 2003 - 05:19 PM
You're correct in saying that the ED80 is not the only solution for a great small scope package. But I will disagree with you on one of your points. A higher quality 80mm will be able to take magnification better than a 100mm thus showing you much more detail, no question about it. Although I haven't received my ED80 yet I have seen planets with both my Celestron 102mm f/5 and TV 85mm. There was not question as to which had better image resolution, regardless of false color.
From what I've heard the ED80 doesn't give you the build quality of a TV but it does seem to give you one heck of a good piece of glass...for the price. I'm anxiously awaiting mine.
PS- Do you know if it's your seeing that is making the image break down after 120X or is it your scope? My Celestron 102 starts to break down very soon after about 160X, even with great seeing.
Posted 01 November 2003 - 05:39 PM
Posted 01 November 2003 - 05:52 PM