Jump to content

sgl_imaging_challenge_6_banner_jupiter_2021.jpg.eacb9f0c2f90fdaafda890646b3fc199.jpg

 

 

Delos dilemma


i Drew
 Share

Recommended Posts

My dilemma is I can only get one eyepiece right now, I'm debating which one to buy. I'm piking between a 10mm, 12mm or the 17.3 of the Delos series. I have a Nexstar 6se f/10, which one would be a good choice for now?

Link to comment
Share on other sites

Firstly, good choice, I have the 10mm Delos and it is an excellent eyepiece.

First question I would ask though, is what other eyepieces do you currently own? Though the Delos may well give larger fields of view with more eye relief than the EPs you currently own, duplication of magnifications is not cost effective, unless you are intending to upgrade your entire eyepiece case.

In your scope, the 3 eyepieces will provide the following.

The 17.3mm will produce a magnification of 88x with a true field of view of 0.8o

The 12mm will produce a magnification of 127x with a true field of view of 0.56o

The 10mm will produce a magnification of 152x with a true field of view of 0.48o

Without knowing what else you already own, I think the 10mm may well be a good first choice. The 0.480 field is large enough to encompass most astronomical objects of interest, but is also producing a magnification in your scope that is bringing into useful planetary eyepiece range as well.

No doubt, others will have different views, but that is my 2 cents worth.

Clear skies,

Matthew

  • Like 1
Link to comment
Share on other sites

Good advice too Matthew!!

For me the 10mm and the 12mm are to close together, I think you would be better served with a 13mm Nagler in between if you are sticking with the quality of TV. I first though would go for the widest FOV and then the shortest and then inbetween.

Alan.

Edited by alan potts
Link to comment
Share on other sites

my advice would be to have a plan for your eventual set. that way you are buying towards something rather than buying 'blind'. e.g. I have two main scopes both approx your focal length (1840mm and 1600mm) and in terms of more expensive eyepieces was sure I should work towards a 26mm Nagler, 13mm Ethos and a 10mm and 8mm Radian for the big scope plus a 6-3mm zoom for the planetary scope. however, I did find that seeing meant that the above range did not provide enough options. so I 'filled in' eventually with cheaper options like TV Plossls and BGOs between 15mm-7mm. I am now lucky enough to have a great range that will fit all scopes although there's always that little imp on your shoulder assuring you that you need more. I tend to buy all my eyepieces (and scopes actually) used.

if you wanted me to recommend one blind then I'd suggest 12mm. 12/13mm is a great workhorse focal length for most scopes and 127x and half a degree is a great base from which to build any collection.

Link to comment
Share on other sites

When are you planning to make your purchase? The fact that 12 Delos isn't available for a few more months may help narrowing your list.

Also, what eyepiece do you have at the moment. If you have none, then I'd buy a 8-24mm zoom instead. If you have a limited budget, a used 10 XW will be much cheaper than a new 10 Delos.

SCT is very tolerant of eyepiece, so you loses a lot of the advantages of Delos vs cheaper designs.

Edited by E621Keith
  • Like 1
Link to comment
Share on other sites

First of all thanks for the great suggestion. When I bought my 6se it came with the 25mm celestron eyepiece then I purchased some cheap eyepiece from Orion a 12.5 and a 31 plossl. I do own a 3x televue Barlow. So this purchase I' doing is basically an upgrade, eye relief is very important for me that's why I going with the Delos since it have 2m eye relief and the option to attach dioptix to it is a plus for my astigmatism if i'm nit wearing my lenses.

Link to comment
Share on other sites

Since you already own a very good 3x barlow, maybe the 17.3mm would be the way to go and it could double up as a high power planetary ep. I have the other two available focal lengths and find them superb. The 10mm XW mentioned above is another to consider. Eye relief is equal to the Delos and if anything the XW is even more comfortable to use.

  • Like 1
Link to comment
Share on other sites

When are you planning to make your purchase? The fact that 12 Delos isn't available for a few more months may help narrowing your list.

Also, what eyepiece do you have at the moment. If you have none, then I'd buy a 8-24mm zoom instead. If you have a limited budget, a used 10 XW will be much cheaper than a new 10 Delos.

SCT is very tolerant of eyepiece, so you loses a lot of the advantages of Delos vs cheaper designs.

I'm really not in a rush and since this is my only upgrade for this time i just want to get an eyepiece i can use a lot, so if i do decide to get the 17.3mm I can wait. I do see stores only have them for pre-order and they're not shipping until next month and some are not until October. On the other hand if I decide to get the 10mm at least that is available right away.

I was able to try the zoom eyepiece, there was a co-club member of mine that had it the other day and I tried them out, it was a 8-24 celestron and the 8-24 hyperion. The hyperion is far superior...no wonder its more expensive :grin: I did like the zoom feature and the ease of not switching eyepiece all the time but I'm a but uncomfortable using it.

Since you already own a very good 3x barlow, maybe the 17.3mm would be the way to go and it could double up as a high power planetary ep. I have the other two available focal lengths and find them superb. The 10mm XW mentioned above is another to consider. Eye relief is equal to the Delos and if anything the XW is even more comfortable to use.

I am leaning towards the 10mm and 17.3mm at this time, the other selling point for me on for Delos is that it has an option to attach a Dioptrx, I don't think the XW has the option and since the price is not much different I think i would rather go TV.

Link to comment
Share on other sites

Firstly, good choice, I have the 10mm Delos and it is an excellent eyepiece.

First question I would ask though, is what other eyepieces do you currently own? Though the Delos may well give larger fields of view with more eye relief than the EPs you currently own, duplication of magnifications is not cost effective, unless you are intending to upgrade your entire eyepiece case.

In your scope, the 3 eyepieces will provide the following.

The 17.3mm will produce a magnification of 88x with a true field of view of 0.8o

The 12mm will produce a magnification of 127x with a true field of view of 0.56o

The 10mm will produce a magnification of 152x with a true field of view of 0.48o

Without knowing what else you already own, I think the 10mm may well be a good first choice. The 0.480 field is large enough to encompass most astronomical objects of interest, but is also producing a magnification in your scope that is bringing into useful planetary eyepiece range as well.

No doubt, others will have different views, but that is my 2 cents worth.

Clear skies,

Matthew

Thak you for providing those information, although I do understand those description I am still a noob in terms of visualizing the true field of view :embarrassed: but anyway, is the 10mm with that 0.48° enough to jump from one object to another having the next object in the field of view? or the 17.3 with .8° the way to go?

Link to comment
Share on other sites

Thak you for providing those information, although I do understand those description I am still a noob in terms of visualizing the true field of view :embarrassed: but anyway, is the 10mm with that 0.48° enough to jump from one object to another having the next object in the field of view? or the 17.3 with .8° the way to go?

To put 0.48o in terms more tangible, that is approximately the diameter of the full moon. When you are star hoping from one object to another, you will always make your life easier if you use a larger field of view. It means less jumps and is more forgiving if you make slight errors in those jumps. I tend to make larger jumps using the finderscope as opposed to just viewing through the EP, though I will then check the field in the EP to make sure it corresponds to the field my star charts are showing me.

Link to comment
Share on other sites

Thak you for providing those information, although I do understand those description I am still a noob in terms of visualizing the true field of view :embarrassed: but anyway, is the 10mm with that 0.48° enough to jump from one object to another having the next object in the field of view? or the 17.3 with .8° the way to go?

I am not sure I understand exactly what you mean. Are you using your C6 SE on GOTO or are you using it on a manual mount. If you want to do manual star hopping than the C6 isn't suitable, the FOV is far too narrow for that. You will need a wide field optical finder scope or unit power finder for that. If you use the C6 GOTO, then the SE mount should be accurate enough to place the object somewhere in the FOV of the 10mm.

This site has a FOV calculator for working out the size of an object for various scope and eyepiece combinations

http://www.12dstring.me.uk/fov.htm

  • Like 1
Link to comment
Share on other sites

This site has a FOV calculator for working out the size of an object for various scope and eyepiece combinations

http://www.12dstring.me.uk/fov.htm

This link looks more appropriate for someone who is framing an object on a CCD for astrophotography, rather than using the scope visually with an eyepiece.

You can work out the field any EP will show with your scope very simply if you know the apparent field of view. The Delos has an APOV of 72o and you divide that by the magnification of the EP in your scope which using the 10mm Delos produces 152x = 0.48o. Magnification is just focal length of telescope divided by focal length of the EP. If you Google the names of any of the show piece objects the amount of detail including angular size is normally readily given which will help you compare it to the field of your EP.

As E621Keith said though as you have the 6se, you can use the GOTO and not worry about star hoping (at least for now).

Link to comment
Share on other sites

The 25mm bundled (E-lux?) eyepiece and the 17.3 Delos show more or less the same amount of sky at about 0.83 degrees. Personally, I don't find the 25 particularly objectionable... sure there are better EPs out there, but it's a good place to start... I find it easy to use and nice and sharp.

That would probably steer me more towards then 10... partly because it's available now :D but also because 150x is a nice magnification and a Delos should give great results for clusters as well as fair-weather (but not great weather) planetary.

Delos are a lot of $$$ though.... you could get a nice set of ES82/68s for $370... :D

Link to comment
Share on other sites

This link looks more appropriate for someone who is framing an object on a CCD for astrophotography, rather than using the scope visually with an eyepiece........

There is a "Switch to visual view" option in red type just above the large Objects menu button. It's easy to overlook though.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use.