Jump to content

  •  

CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.

Newbie ? ... is it the binoculars or my eyes?

This topic has been archived. This means that you cannot reply to this topic.
3 replies to this topic

#1 Guest_**DONOTDELETE**_*

Guest_**DONOTDELETE**_*
  • -----
  • topic starter

Posted 09 May 2005 - 09:08 AM

I need some help to understand what I am seeing …
I just received a set of Celestron Skymaster 15x70 bins. They arrived and were somewhat out of collimation, so I did adjust the collimation. I am viewing from an area with moderate light pollution. I have the bins mounted on a good tripod. I am a Professional photographer, so I am accustom to looking through very good optics and have good visual acuity. I should also mention that I enough astigmatism to make opticians grimace when they read my prescription, so I must wear corrective lenses while viewing!

Once the collimation was corrected, the Skymaster’s performed very well for terrestrial viewing. When I finally got a clear night, I took a look at Jupiter … what I saw was gull wings with a lot of color fringe! However, if I changed the placement of my eyes relative to the oculars, I could get Jupiter to become a reasonable sphere with some expected color fringe.

Am I seeing the results of inexpensive (cheap) bins?
Do I just have a bad pair?
Is it still a collimation issue?
Will a bin with FMC improve the situation?
or …

Given the amount of astigmatism that I have, should I expect this type of performance from any binocular that I choose?

#2 EdZ

EdZ

    Professor EdZ

  • *****
  • Posts: 18,849
  • Joined: 15 Feb 2002

Posted 09 May 2005 - 09:13 AM

When I finally got a clear night, I took a look at Jupiter … what I saw was gull wings with a lot of color fringe! However, if I changed the placement of my eyes relative to the oculars, I could get Jupiter to become a reasonable sphere with some expected color fringe.

Am I seeing the results of inexpensive (cheap) bins?
Do I just have a bad pair?
Is it still a collimation issue?
Will a bin with FMC improve the situation?
or …

Given the amount of astigmatism that I have, should I expect this type of performance from any binocular that I choose?


results of cheap? possibly

bad pair? can't tell from info

is it collimation? could be

will FMC improve? NO

expect this from astigmatism? NO


You cannot properly collimate a pair of binoculars in daylight on terrestrial objects. At best you can get a coarse collimation that then needs to be refined on stars.

edz

#3 Guest_**DONOTDELETE**_*

Guest_**DONOTDELETE**_*
  • -----
  • topic starter

Posted 09 May 2005 - 09:55 AM

Ditto everything that EdZ. And I would like to drive home the issue of using a star for conditional alignment. Using terrestrial objects for course prism adjustments is ok IMO, but the best tool is a light sourse at infinity or a star...the next best thing.

I have never used Skymasters so I can say if they're are cheaply made or not. You may want to read reviews on this particular bin to get a sense of its quality (or possibly lack there of..)

#4 Glassthrower

Glassthrower

    Vendor - Galactic Stone & Ironworks

  • *****
  • Vendors
  • Posts: 18,503
  • Joined: 07 Apr 2005

Posted 09 May 2005 - 10:51 AM

what I saw was gull wings with a lot of color fringe!


I've never had that problem with my 15x70 Celestrons. It could be a manufacturing defect, possibly they were dropped or mishandled during shipping, or maybe it is just poor optics. My 15x70's seem to have better image-clarity than my 25x100's also made by Celestron. And judging by everything I have read about these binocs in the last couple of months, the quality of Celestron optics is not consistent. Some report great views, others say just the opposite.

My advice, for what's it worth, is to try out a friend's set of binos and see if you experience the same problem. If not, then it's likely your binos. If you experience the same kind of issues while viewing through different binos, then it might be your eyes.

Mike


CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.


Recent Topics






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics