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.

Photo

Xt10i need advise on high power eps.

  • Please log in to reply
11 replies to this topic

#1 hiddenwolf

hiddenwolf

    Ranger 4

  • *****
  • topic starter
  • Posts: 301
  • Joined: 26 Dec 2007
  • Loc: Milford Nh

Posted 12 September 2019 - 07:36 AM

Good morning. I have a xt10i full flocked tube moonlight 2ich cr2 focuser and currently have

TV 27mm pano 44x 5.7mm ex pup
TV 13mm ethos 92.3x 2.8mm
TV 2x powermate gives 184x mag with 13 ethos

What I am trying to do is get the most out of my telescope by getting as much magnification to reach distant objects and planetary viewing.

I did at one time have the 3.7 ethos and 4x powermate but didnt like the 110 view.

I am considering the tv delos 4.5mm which would give 266.7 x and .95 ex pupil

Or the delos 3.5mm would give 342x and .74mm ex pupil


Anyone have any experience with these or recommend anything better or comparable?

Thanks in advance

#2 Sarkikos

Sarkikos

    ISS

  • *****
  • Posts: 30475
  • Joined: 18 Dec 2007
  • Loc: Per sylvam ad astra

Posted 12 September 2019 - 07:40 AM

Consider the Tele Vue Zoom 6-3mm.  It has a constant 50 degree AFOV and is parfocal.  The optical performance is similar to a decent ortho.

 

Mike


  • Mike G. likes this

#3 tomjones

tomjones

    Viking 1

  • *****
  • Posts: 706
  • Joined: 25 Jan 2011
  • Loc: along the 32nd parallel

Posted 12 September 2019 - 08:52 AM

You need 4mm=300x

5mm=240x and 6mm=200x

 

Forget zooms they are all substandard to the best for planetary like Delos, Pentax XW and TV Delites (my favorites).

If the atmosphere allows you to reach these powers then consider a 3.5mm for 340x, or even a 3mm for 400x.



#4 Sarkikos

Sarkikos

    ISS

  • *****
  • Posts: 30475
  • Joined: 18 Dec 2007
  • Loc: Per sylvam ad astra

Posted 12 September 2019 - 10:37 AM

Don't forget zooms.  The Nagler Zooms perform as well or very nearly as well as Delos, XW's or Delites.  The advantage of a zoom is that they zoom.  You can dial in the best magnification for the current conditions on-the-fly without having to switch among a set of single focal length eyepieces. 

 

The Leica Zoom is as good as a set of XW's for planet observation, but are expensive.  However, when compared to a set of XW's, the Leica Zoom plus a Barlow is not so expensive after all.

 

In fact, all of these eyepieces are "substandard" compared to the XO's and ZAO's.  These eyepieces are the best for planet viewing, not the Delos, XW's or Delites.  Unfortunately, the XO's and ZAO's are no longer available new.  However, the Delos, XW's and Delites are solid middle-tier or upper middle-tier planet eyepieces.

 

Mike


Edited by Sarkikos, 12 September 2019 - 10:54 AM.

  • CeleNoptic likes this

#5 hiddenwolf

hiddenwolf

    Ranger 4

  • *****
  • topic starter
  • Posts: 301
  • Joined: 26 Dec 2007
  • Loc: Milford Nh

Posted 12 September 2019 - 11:40 AM

I have been spoiled by large eye relief  since my origional orion ploss  with 27 pano   17T4   and 13 Ethos,  that 10mm eye relief would bring me back to small eye relief eye pieces although that nagler 6-3 mm would cover my entire max magnification with one EP. 

 

 

thats why i was considering the delos with 20mm eye relief  Ill do some more researching and see if i can see through a 10mm and remember how it was  this was about 13 years ago. 


  • Sarkikos likes this

#6 Miranda2525

Miranda2525

    Surveyor 1

  • *****
  • Posts: 1822
  • Joined: 12 Jul 2016

Posted 12 September 2019 - 01:04 PM

Delos. You will not regret getting them in any way.


  • hiddenwolf likes this

#7 SteveG

SteveG

    Cosmos

  • *****
  • Posts: 7736
  • Joined: 27 Sep 2006
  • Loc: Seattle, WA

Posted 12 September 2019 - 03:16 PM

Just be advised that 266x is very high power only achievable for good planetary viewing on the rarest of nights.

 

Further, 342x is simply too high of power for good planetary viewing with a 10" f5 dob. YMMV.

 

I think the Delos / XW options will suit you very well. I use the XW's, and typically it's the 7 mm. On rare nights the 5 mm works (292x). I've never had the 3.5 mm in my 10" f5 dob. All of my eyepieces are magnified an additional 1.15x due to the Paracorr.



#8 lakland5

lakland5

    Mariner 2

  • *****
  • Posts: 219
  • Joined: 24 Oct 2015

Posted 12 September 2019 - 03:20 PM

I think the Delos / XW options will suit you very well. I use the XW's, and typically it's the 7 mm.

Like Steve, I also find 7mm to be the useful maximum most of the time in my XT10.  I assume that's due to seeing and transparency in the Chicagoland collar county where I do my observing.



#9 Sarkikos

Sarkikos

    ISS

  • *****
  • Posts: 30475
  • Joined: 18 Dec 2007
  • Loc: Per sylvam ad astra

Posted 12 September 2019 - 04:45 PM

Just be advised that 266x is very high power only achievable for good planetary viewing on the rarest of nights.

 

Further, 342x is simply too high of power for good planetary viewing with a 10" f5 dob. YMMV.

 

I think the Delos / XW options will suit you very well. I use the XW's, and typically it's the 7 mm. On rare nights the 5 mm works (292x). I've never had the 3.5 mm in my 10" f5 dob. All of my eyepieces are magnified an additional 1.15x due to the Paracorr.

Is the seeing that poor in Seattle?  Around 250x is par for the course when viewing Jupiter, Saturn or Mars here in Maryland on relatively good nights.  I wouldn't call it very high power.  It's only 25x per inch.  That's cruising speed for planet viewing.

 

On nights of excellent seeing - not so rare in the late Spring and Summer - 350x or higher is very possible for the bright planets.  400x or more is not out of the question for Saturn or Mars when it has good altitude.

 

Mike


Edited by Sarkikos, 12 September 2019 - 04:46 PM.


#10 csrlice12

csrlice12

    ISS

  • *****
  • Posts: 24576
  • Joined: 22 May 2012
  • Loc: Denver, CO

Posted 12 September 2019 - 11:39 PM

7mm the norm here too, 5mm on a good night....of course thee seeing here is average at best...now if you're into DSOs, our transparency and access to dark skies is fantastic.   



#11 hiddenwolf

hiddenwolf

    Ranger 4

  • *****
  • topic starter
  • Posts: 301
  • Joined: 26 Dec 2007
  • Loc: Milford Nh

Posted 13 September 2019 - 08:56 AM

  Since I live in the state of the highest wind speed recorded on the planet  being Mt washington,  We have pretty turbulent skies around here in NH,   however  Up in New Durham, the skies are Dark and still and far away from Light Pollution, This past week  was on Vacation there on day 1   Tuesday,  we had the clearest skies that week  seeing and transparancy showed dark blue and black on my clear sky clock.  And usually I gear up for that one week a year   However I have some spots local to me that are dark enough at zenith to reach DSO. 

 

 

 I am really into DSO,  galaxy  nebula,   and planets  

 

I have OIII and Hydrogen Beta both in 2" format

 

all of my current EP are 2Inch,  but with high magnification you will get distortion and vignetting 

 

 so my plan is to get the Delos 6mm   which would yield 200x   and with powermate yield 400x  just for the possibility of perfect seeing 

 

currently my 13 ethos with powermate is 184x  100 degree and 1.1  degree field. 

 

I would like to get 250x more away from my heavy 13e and powermate but i think 6mm @ 200x with option for 400x will do me well.  


  • Sarkikos likes this

#12 SeattleScott

SeattleScott

    Fly Me to the Moon

  • *****
  • Posts: 5693
  • Joined: 14 Oct 2011

Posted 14 September 2019 - 02:40 PM

200-300x is pretty typical on a good night in Seattle, in the city anyway. Seeing is less stable in the mountains.

I would go 4.5mm myself. Or even 5mm. 300x is fairly rare and requires precise collimation.

Scott


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