ES 14mm 82 vs ES 12mm 92 for f5 dob

[michelbechara]

Hello,

Could someone help me understand if there is any really observable difference between the following 2 eyepices for a f5 dobsonian (305/1500)

 

1) ES 14mm 82 deg

Focal length: 14mm     Mag: x107,5    Exit Pupil: 2,84mm    FOV:82    TFOV:0,76

2) ES 12mm 92 deg

Focal length: 12mm     Mag: x125    Exit Pupil: 2,43mm      FOV:92      TFOV:0,73

 

From looking at the data, the only notable difference is the higher mag achieved by the ES 12 mm and maybe a better contrast but by looking at the rest, it is looking pretty similar. 

The price difference between the 2 eyepieces is huge, the  ES 14mm 82 deg priced at 175€ and the ES 12mm 92 deg 479€ so I am wondering if the price difference for the 12mm is justifiable? 

Could there be a better optical quality/better build that is being overlooked?

Thanks for the helps and thoughts!

 

 

 

 

[Ags]

The 12mm offers much more eye relief with a wider apparent field of view. That needs a lot more glass and polishing, explaining the weight and cost.

[Dave scutt]

Hi michelbechara. 

Sounds like you've got the same scope as me I'm using the 14mm es82 works very well . I couldn't afford the extra 300 euros to justify the extra 10% fov.

Dave

[amaury]

You get more mag, at almost the same TFOV, with noticeable more eye relief.  Diminishing returns is something very common in the hobby to be honest. Whether the price difference is justifiable is totally your call. For most people it would be hard to justify. 

[Louis D]

I've never tried the 14mm ES82, but I do have the 12mm ES92.  The ES92 is nearly perfectly sharp and flat of field to the edge at f/6.  I would imagine it degrades slightly at f/5.

I have strong astigmatism in my observing eye, so I need to wear eyeglasses at the eyepiece.  The ES92s have just enough eye relief to comfortably take in the entire field of view with glasses on.  As far as I know, the ES82 series does not.

I've read multiple reports that the ES92 series is sharper than the ES82 series, though not quite as sharp as the TV Ethos and Nikon NAV-HW series.

It all depends on what you want or need from an eyepiece and what your budget is as far as deciding to which to buy.