|
|
Post by istarmullet on Jan 2, 2014 11:00:11 GMT -5
Last night the seeing and skies were the best they have been here in San Diego, perfect in both regards. I let my Forfax cool for a couple hours as I did my Celestron CPC 1100. Checked Capella first in each scope to see how the atmosphere was doing and found it was very steady. Checked collimation on the latter scope, spot on. Then I waited for Jupiter.
Jupiter was stunning in the CPC. Absolutely perfect conditions lead to views that were photographic in detail. I was using my Doctor 12.5mm eyepiece so was viewing at 233X. I dropped down to a 7mm Tak eyepiece but the magnification of 400X proved to be just a tad too much, so back to the Doctor. Bands with clear and crisp and boils and turbulence were plainly evident and was GRS.
Then I went to to the Forfax. I was going between my Maysuma 7.5mm and a Pentax 10mm for 204X and 153X. The disc was not as large as it was in the CPC but the views were just as spectacular. Every amount of detail in the CPC was clearly seen in the smaller APO...albeit on a smaller scale so to speak.
I am happy to own each scope.
|
|
|
|
Post by mikey cee on Jan 2, 2014 13:19:21 GMT -5
Hi Mullet. You are damn lucky to have a C11 to fool around with. I unfortunately have no more room in the observatory to mount one anyways. If I recall the Forfax is a 3 element correct?  Mike |
|
|
|
Post by istarmullet on Jan 2, 2014 14:00:04 GMT -5
Yes, three element indeed. Great scope.
|
|
|
|
Post by Mike on Jan 3, 2014 9:43:07 GMT -5
I was always happy with the view through those scopes. Long focal length triplets are great. It's a shame they didn't generate more interest. Everyone is fooled by the mass trend for short focal length scopes. Then they wonder why they can't get any image size without using a 5mm or shorter eyepiece. The tube wasn't that long on those 140s although the heavy triplet did put some weight all the way out on the end. What mount do you use with it?
|
|
|
|
Post by istarmullet on Jan 3, 2014 10:06:08 GMT -5
You are right Mike, the length of the tube is easy to manage. I have no problem moving or mounting the scope. The weight is indeed on the front end, once one gets used to it, transporting is a snap.
I am using a losmandy G11, no Gemini, and it is a perfect match. I put my Perseus f15 up on it with a strut, that was a stretch.
Cool down is the only "issue" with this scope, but Ales was upfront ( no pun intended) that the large triplet would take time to settle.
|
|
|
|
Post by Ales - iStar Optical on Jan 5, 2014 3:41:59 GMT -5
Last night the seeing and skies were the best they have been here in San Diego, perfect in both regards. I let my Forfax cool for a couple hours as I did my Celestron CPC 1100. Checked Capella first in each scope to see how the atmosphere was doing and found it was very steady. Checked collimation on the latter scope, spot on. Then I waited for Jupiter. Jupiter was stunning in the CPC. Absolutely perfect conditions lead to views that were photographic in detail. I was using my Doctor 12.5mm eyepiece so was viewing at 233X. I dropped down to a 7mm Tak eyepiece but the magnification of 400X proved to be just a tad too much, so back to the Doctor. Bands with clear and crisp and boils and turbulence were plainly evident and was GRS. Then I went to to the Forfax. I was going between my Maysuma 7.5mm and a Pentax 10mm for 204X and 153X. The disc was not as large as it was in the CPC but the views were just as spectacular. Every amount of detail in the CPC was clearly seen in the smaller APO...albeit on a smaller scale so to speak. I am happy to own each scope. I will arrive in San Diego on 15th of January, but must continue to Arizona the next day. If I have time before my flight back to Europe, it would be great to meet. I have one question. Is the OPT astronomy club still active? They used to meet once a month in Ocotillo desert. I was a member many years ago, enjoyed those observing sessions very much. |
|
|
|
Post by istarmullet on Jan 6, 2014 0:49:21 GMT -5
Ales, pm me.
|
|
|
|
Post by philbarker on Jan 10, 2014 18:11:24 GMT -5
interesting comparison. I have an older carbon fiber c-11 and down here in New Zealand we haven't had Jupiter as high but I've still seen some stunning views. Most of the time my 5 inch f-9.4 refractor shows just as much with slightly lower power. I also love 233 x on Jupiter in the 11 I use a uni optics volcano type ortho. I've taken a lot of time to collimate the 11 and it startests extremely well around 1/8th wave p-v using suiters startesting method. Absolutely blows away a Meade 12 the old club had which was closer to 1/4 wave.
The contrast on the really fine details is clearly is where the refractors do the business and I expect my new 150mm f-12 Istar scope to really perform on Jupiter. Those ovals to me are the key and the festoons between the 2 belts.
Saturn is high down here and the c11 works to advantage on Saturn at 450 plus on good nights. I don't expect to 6 to beat it on Saturn but it will certainly run it close.
your description of the 140mm triplet reminds me of the views in twin brother kevs 130mm zeiss apq. The vividness of the detail is too much for the eyeball and brain to take in.
Hopefully in next couple of nights I get a go at Mars Jupiter and Saturn in the early hours. |
|
Mike
