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Nikon NAV SW eyepieces
Pentax XW eyepieces
Vixen LVW eyepieces
PORTA Accessories
Bolt Cases

NEW! The T-REX and T-MOUNT Alt-Azimuth mount

Dual axis slow motion controls and 4096 step encoders standard!

Can carry up to a C-11 with no counterweights!

All Made in Japan

Click here for details!


Orthoscopic Eyepieces

Kelner Eyepieces

Erfle Eyepieces


 Kokusai Kohki OR eyepieces are hand crafted and individually inspected before we ship. They come with plastic eyepiece caps, and carry a one year Kokusai Kohki parts and labor warranty. My promise to you: You will either LOVE your OR eyepiece or you get your money back!
 User comment:
Your OR25 could have the highest sharpness, throughput, contrast and resolution theoretically possible. I`d say your OR 18s and especially the OR25 are in a class all their own regardless of maker and price.
M Zander (Nishinomiya City, Japan 
 
 Top Notch workmanship, design and optical performance
Maximum sharpness, resolution, throughput and contrast

--- At a very reasonable price---

Japanese Orthoscopic Eyepieces
 
Get Real Japanese Orthoscope Eyepieces!

A few focal lengths have sold out,but the OR4 / 5 / 12.5 and 18mm eyepieces remain available in 0.965" barrel sizes. Compare size against the 1.25" size OR25 at upper left corner.
  Our world famous lineup of orthoscopic eyepieces sport the highest quality Japanese workmanship, sharp "eagle-eye" views and excellent color correction. Our OR eyepieces will satisfy even the most demanding planetary observer, including those used to much more expensive and "flashy" name brand eyepieces, but at 1/4 ~1/10 the cost! OR YOUR MONEY BACK!

Our OR eyepieces are all lovingly handmade, one at a time by craftsmen at the Tokyo factory. Producing them now for over 40 years, you can be sure of optical, mechanical and design quality you can be proud of for years to come. High magnification inclined apo-refractor, Maksutov, SCT and Mewlon users will be especially pleased with their planetary and double star viewing performance. The gorgeous barrel design includes snug filter threads and a tight, sharp field stop that precisely defines the field of view. All OR eyepiece also include caps on both ends.

For maximum image definition, contrast and light transmission, the eye lens of each eyepiece is multicoated, all other surfaces are magnesium flouride coated. Eye relief is plentiful and images merge well when used in a binocular viewer. Apparent field of view of all focal lengths hovers in the 45< degree range.

This level of quality comes at the very low price of 4,800 yen each, meaning that getting even an entire set, or doubling up for binoviewing, is a more than reasonable proposition. Eyepieces weigh in at 65~95 grams for 1.25" and from 40 to 65 grams in the .965" size. Eye lens diameters for the shortest three focal lengths range from 3mm for the OR4, 4mm for OR 5 and 5mm for OR6.

Our OR eyepieces are available in either 1.25" (4mm / 5mm / 6mm / 7mm / 9mm / 12.5mm /18mm /25mm) or 0.965" (4mm / 5mm / 12.5mm /18mm ) barrel size. Please specify FL and barrel size upon your order. Every OR eyepiece includes plastic caps on both ends.

Please see below for eyepiece specs. The 1.25" barrel size ORs are usually in stock for immediate delivery. The 0.965" barrel size ORs and Japanese made Kelner and Erfle eyepieces are available on a special order basis, with delivery about 2~4 weeks from your order.( Sorry, the OR7, 8,9 and 25mm, in .965" barrel size, are sold out and there are no plans for another production run)




 
My promise to you: You will either love your OR eyepiece or you get your money back!




 
Made in Japan highest quality ERFLE eyepieces available in 16mm, 20mm and 25mm focal lengths (1.25" barrel only).
Kelner 6 / 9 / 12 / 18 / 20 and 25mm also available on a Made to Order basis (2~4 week delivery, please specify .965" or 1.25" barrel sizes)



Kokusai Kohki ORTHOSCOPIC (Or), KELNER (K) and ERFLE (ER) Eyepiece Specifications
Eyepiece
Type
AVAILABLE
Barrel Sizes
Eye Lens OD
(mm)
F.O.V (degrees)
Eye Relief (mm)
Weight (gr)
Item No
Item No
Price (Yen)
 
.965"
1.25"
.965"
1.25"
.965"
1.25"
OR 4mm
.965" or 1.25"
4
41
41
3.5
40
80
1012
1004
4,800 Yen
OR 5mm
.965" or 1.25"
4.5
43
43
4.0
40
85
1013
1005
4,800 Yen
 OR 6mm
.965" or 1.25"
 5.8
43
 43
 4.8
42
 90
SOLD OUT
1006
 4,800 Yen
OR 7mm
.965" or 1.25"
6.5
42
42
5.6
45
90
SOLD OUT
1007
4,800 Yen
OR 9mm
.965" or 1.25"
8.3
42
42
7.2
47
92
SOLD OUT
1008
4,800 Yen
OR 12.5mm
.965" or 1.25"
11
44
44
10
50
96
1017
1009
4,800 Yen
OR 18mm
.965" or 1.25"
17
44
46
14.4
65
97
1018
1010
4,800 Yen
OR 25mm
.965" or 1.25"
21
45
47
20
76
100
SOLD OUT
1011
4,800 Yen
Kelner 6mm
.965" or 1.25"
5.8
42
42
4.8
55
85
1028
1020
3,300 Yen
Kelner 9mm
.965" or 1.25"
10
44
44
7.2
60
105
1029
1021
3,300 Yen
Kelner 12mm
.965" or 1.25"
8.5
40
40
4.0
62
120
1030
1022
3,300 Yen
Kelner 18mm
.965" or 1.25"
16.8
45
47
9.6
65
100
1031
1023
3,300 Yen
Kelner 20mm
.965" or 1.25"
16.8
45
47
15
65
100
1032
1024
3,300 Yen
Kelner 25mm
.965" or 1.25"
16.8
42
45
16
75
105
1033
1025
3,300 Yen
Erfle 16mm
1.25"
15.5
N/A
60
9.6
NA
175
N/A
1001
8,190 Yen
Erfle 20mm
1.25"
21
N/A
62
11
NA
175
N/A
1002
8,190 Yen
Erfle 25mm
1.25"
22
N/A
62
21
NA
175
N/A
1003
8,190 Yen
The above "SOLD OUT" 0.965" size OR eyepieces are out of stock and commencing a new production run requires a minuimum 500 pc order per size. Hence the SOLD OUT designation (we don`t anticipate another production run at this time).....The good news is that we plan on being able to deliver the remaining .965" size ORs, and all the .965" size Kelners, for the time being, with about a 2 ~ 4 week delivery time from order. The 1.25" ORs are usually in stock and will continue to around for a while :- ) BG


We ship via fast EMS Airmail to anywhere in the world!
to ship you 1 ~ 3 OR eyepieces
Please add 2,000 Yen to your order
to ship you 4 ~ 6 OR eyepieces
Please add 2,500 Yen to your order
to ship you 7~10 OR eyepieces
Please add 3,500 Yen to your order
 to ship you 11+ OR eyepieces
Fee varies according to destination. Please request a quote
For currency conversion (OANDA) click here
Payment via PayPal welcome! Our Paypal account is under my email address: magellan@kkohki.com

Sorry, no shopping basket... For orders and inquiries Please email me (Barry Gooley) directly



 
NEW! 

NIKON NAV SW Eyepieces



Hot off their optical benches, Nikon commemorated the International Year of Astronomy 2009 with the birth of their brand new and long awaited NAV-SW series eyepieces. Manufactured in five different focal lengths, all are now currently available except the NAV 10SW, which is scheduled to be released in March 2010.

Nikon NAV SWs, based on their excellent eyepieces for Nikon spotting scopes, have evolved to meet the requirements of high level astronomical observation, with the deepest attention devoted to exquisite rendition of astronomical point sources of light, while also taking a chapter for the digiscope design world, which demands flat fields and sharp images right to the very edge of the field of view. The NAV SW design emphasizes suppresion of field curvature and all astigmatism to bring about the maximum improvement in edge of field fidelity wthout sacrificing the quality of the image at the central of field.

The compact Nikon NAV SWs are 72 degree FOV eyepieces that come with 1.25" barrels that are threaded for standard filters. The comfortable eye relief specs for each eyepiece are designed to also harmonize with the optical performance of that eyepiece. Also, removal of exit pupil aberrations virtually eliminates any instance of kidney bean blackout effect, regardless of where the eye is placed during observation. The excellent color balance of the NAV SWs was derived through rigorous testing of this optical parameter on terrestrial objects, insuring the highest degree of planetary and lunar color rendition. Multicoatings on every optical surface make sure that these images are also as bright and otherwise distortion free as possible.

The Nikon NAV SW exterior design is somewhat reminiscent of the tried and true Nikkor lens design, with an attractive, high quality appearance, and rollets located around the entire circumference making the eyepieces easy and sure to grip even in darkness, or with gloved hands. A flexible silicone rubber eye shield on the top of the eyepiece helps block streets lights and other annoying sources of light pollution, especially a help when viewing sensitive planetary and lunar surface details at high magnifications. The rubber eyeguard is painted with a unique phosphorescent logo that glows ever so slightly to help make seeing the eyepieces (or finding them) in the dark just a little easier.

Nikon NAV SWs moisture resistant design will provide long years of constant and worry free service and viewing pleasure to discriminating astronomers in any observing environment worldwide.

The combination of the ideal optical qualities of a flat and wide 72 degree FOV that is sharp from edge to edge, excellent color rendition, comfortable eye relief intelligently designed to harmonzie specifically with each eyepiece, a beautiful and compact body design, highest quality Japanese glass, multi-coatings and exterior materials, and a good selection of focal lengths, makes the Nikon NAV SWs a true and new winner in the ever expanding world of 21 century astronomy.

NIKON NAV SW Series (visual) Eyepiece Specs
Item
f/l
Field of View
Eye relief
Lens Design
Size (mm)
Weight (gram)
Price (Japan Yen)
NAV 5SW
5mm
72 degree
18mm
6 group / 8 lens
56.5 x 91
300
37,900 Yen
NAV 7SW
7mm
72 degree
17mm
6 group / 8 lens
56.5 x 78
290
37,900 Yen
NAV 10SW
10mm
72 degree
19mm
6 group / 8 lens
56.5 x 79
300
37,900 Yen
NAV 14SW
14mm
72 degree
18mm
5 group / 7 lens
56.5 x 77.5
275
37,900 Yen
NAV 17.5SW
17.5mm
72 degree
26mm
5 group / 8 lens
56.5 x 94.5
365
42,900 Yen
EiC-16
converter lens
Specifically optimized for Nikon NAV SWs, the EiC-16 provides a 1.6X tele-extension for the NAV SWs, with even more enhanced field curvature and astigamitism suppresion. Can also be used with other makers` eyepieces, 1.25" size
21,000 Yen
Nikon NAV 10SW and EiC-6 delivery is scheduled for mid March. All others in stock and ready for immediate shipment

We ship via fast EMS Airmail to anywhere in the world!
to ship one NAV SW eyepiece
Please add 3,000 Yen to your order
for additional eyepiece
Fee varies according to destination. Please request a quote
For currency conversion (OANDA) click here
Payment via PayPal welcome! Our Paypal account is under my email address: magellan@kkohki.com

Sorry, no shopping basket... For orders and inquiries Please email me (Barry Gooley) directly


click each for larger image


 

 
 Pentax Eyepieces

 




70 degree apparent field of view, Eye relief 20mm
Practically waterproof, to assure you of years of problem-free observing
Beautiful to look AT, as well as look through

Kokusai Kohki offers the fabulous Pentax XO and XW series wide angle SMC (super multi-coated) eyepiece lineup.Though not rock bottom low price, this premium eyepiece provides tack sharp and bright images to the edge of the very wide field. Adding in superior light throughput and plenty of eye relief, the XW series deserves a place in every serious observer`s eyepiece case. The Pentax XW series also offers the discriminating observer the following benefits:

* All focal lengths standardized with a dazzling 70 degree field of view, and generous 20mm of eye relief, for ease of viewing even when wearing glasses.

* A brand new design that incorporates high refractive index Lanthanum glass elements. This sophisticated design corrects and balances all optical abberrations for images that approach optical perfection. An added plus is the extra effort made to compensate for spherical aberations found in the human eye, virtually removing kidney bean and blackout effects. A truly easy to view through eyepiece.

* Proprietary Pentax multi-coatings on every air to glass surface, with special coatings also applied to all cemented surfaces, assuring you of superior light transmission (550nm transmits at approximately 96%, and overall transmission of all visible wavelengths measured at over 90%)

* Computer designed field stops placed at critical locations provide the highest degree of high contrast views

* Choose from 3.5mm, 5mm, 7mm, 10mm, 14mm, 20mm, 30mm and 40mm focal lengths. A full lineup of all your favorite focal lengths let you choose exactly the right eyepiece for low power viewing of Milky way star fields all the way to medium and high power planetary and lunar observing.

* The XW series conforms to a JIS 4 "daily use" waterproofing rating, assuring you that your eyepiece will give you maximum value over the years by remaining unaffected by the usual dewing and wetness that occur during your observation sessions (Note: this level does NOT assure waterproofing if the eyepiece is totally immersed in water).

* The WX series 3.5mm to 20mm eyepieces use a 1.25" size barrel and the XW30mm and XW40mm come with a 2 inch barrel.

* Height adjustable rotating eye caps let you easily place your eye at the exact location for comfortable viewing and perfect eye relief. Removing the eye cap exposes a 43mm / P0.75mm pitch male thread, for accessory attachment.

* All Pentax XW and XO eyepieces are threaded for standard 1.25" , or 2" size filters, depending on their barrel sizes.

 Pentax XW Series (visual) Eyepiece Specs
Focal Length
Field of View
Eye relief
Lens Design
 Field Stop(mm)
Size (mm)
Weight (gram)
Price (Japan Yen)
XW3.5mm
70 degree
20mm
5 group / 8 lens
4.3
61 x 137
405
32,800 Yen
XW5mm
70 degree
20mm
5 group / 8 lens
6.2
61 x 127
395
29,800 Yen
XW7mm
70 degree
20mm
6 group / 8 lens
8.8
61 x 120
390
29,800 Yen
XW10mm
70 degree
20mm
6 group / 7 lens
12.4
61 x 110
390
29,800 Yen
XW14mm
70 degree
20mm
6 group / 7 lens
17.6
61 x 97
365
29,800 Yen
XW20mm
70 degree
20mm
4 group / 6 lens
24.0
61 x 86
355
29,800 Yen
XW30mm
70 degree
20mm
6 group / 7 lens
36.2
76 x 123
740
43,800 Yen
XW40mm
70 degree
20mm
5 group / 6 lens
46.5
76 x 117
700
45,800 Yen
  Pentax X0 Series (high magnification visual and eyepiece projection) Eyepiece Specs)
XO 2.5mm
   44 degree
3.9mm
3 group / 6 lens
 
37 x 56
105
NEARLY GONE *
28,300 Yen
XO 5mm
   44 degree
3.6mm
3 group / 5 lens
 
37 x 45
90
NEARLY GONE *
28,300 Yen
   Pentax XP Series (eyepiece projection) Eyepiece Specs)
XP 3.8mm
N / A
N / A
3 group / 5 lens
 
30 x 33
40
NEARLY GONE *
16,000 Yen
XP 8mm
N / A
N / A
5 group / 6 lens
 
30 x 42
50
SOLD OUT
XP 24mm
N / A
N / A
5 group / 6 lens
 
30 x 69
70
NEARLY GONE *
23,200 Yen
* So few remain currently in inventory so pls check availability again at time of your order. All are subject to prior sale
Pentax XF Series (for field scope and binoviewers) Eyepiece Specs
 XF 8.5mm
60 degree
18mm
4 group / 6 lens
 
43 x 83
150
15,750 Yen
 XF 12mm
60 degree
18mm
4 group / 6 lens
 
43 x 78
150
15,750 Yen


     
 XP Series Eyepiece
XP 3.8mm
XP 8mm
XP 24mm


We ship via fast EMS Airmail to anywhere in the world!
to ship one XW eyepiece
Please add 3,000 Yen to your order
for additional eyepiece
Fee varies according to destination. Please request a quote
to ship XO or XP eyepiece (and no XWs)
please use OR eyepiece EMS airmail pricing
For currency conversion (OANDA) click here
Payment via PayPal welcome! Our Paypal account is under my email address: magellan@kkohki.com

Sorry, no shopping basket... For orders and inquiries Please email me (Barry Gooley) directly

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 VIXEN LVW Eyepieces

 


Highest quality Japanese design and finish, at a very reasonable price

Kokusai Kohki offers the Vixen wide angle LVW eyepiece lineup to our overseas friends and neighbors. The LVW lineup provides a wide 65 degree field of view, with plenty of eye relief. Special multi-coatings, a solid optical design and a Japanese standard excellent finish, are all included at a most reasonable price. For high end viewing quality without the high end price tag, we heartily recommend the Vixen LVW lineup, including the low cost and fun LV 8 ~ 24mm zoom eyepiece from the previous "LV" series of eyepieces. Benefits the Vixen LVW eyepiece series offers the discriminating observer include the following:

* For maximum light throughput and bright images, all lens surfaces are fully multi-coated.

* All LVW focal lengths provide a generous 20mm of eye relief, to allow many comfortable hours of viewing, even when wearing glasses

* LVW 3.5mm to 2mm are 1.25" barrel size, the NLVW30 and LVW42 are 2" barrel size, and all offer a nearly unvignetted full 65 degree field of view

* All LVW eyepieces are threaded either for standard 1.25" or 48mm size filters.

* The NLVW-30mmeyepiece provides a very bright, crisp 65 degree FOV with excellent color rendition. The NLVW-30`s exterior is an interesting contrast to the rest of the LVW lineup and the eyepiece is strikingly lightweight, at only 363grams. Well priced, at only 20,160 yen, and perfect for low power wide field views through Schmidt Cassegrains, large aperture dobs and even short focal length achromat to apo refractors.

 VIXEN LVW Series Eyepiece Specs (1.25 inch sleeve)
Focal Length
Field of View
Eye relief
Lens Design
Weight (gram)
Price (Japan Yen)
LVW3.5mm
65 degree
20mm
5 group / 8 lens
510
21,000 Yen
LVW5mm
65 degree
20mm
5 group / 8 lens
500
20,100 Yen
LVW8mm
65 degree
20mm
6 group / 8 lens
495
17,600 Yen
LVW13mm
65 degree
20mm
6 group / 7 lens
460
18,400 Yen
LVW17mm
65 degree
20mm
6 group / 7 lens
440
19,300 Yen
LVW22mm
65 degree
20mm
4 group / 6 lens
430
21,100 Yen
  VIXEN LVW Series Eyepiece Specs (2 inch sleeve)
 NLVW30mm
 65 degree
 22.4mm
3 group / 5 lens
 363
 20,100 Yen
 LVW42mm
 65 degree
 20mm
 6 group / 7 lens
 545
 31,900 Yen
 VIXEN LV Series (visual) Zoom Eyepiece Specs
LV8 ~ 24mm
60 ~ 40degree
19mm
3 group / 6 lens
215
15,750 Yen



We ship via fast EMS Airmail to anywhere in the world!
to ship one LV Zoom or LVW eyepiece
Please add 2,500 Yen to your order
for additional eyepiece
Fee varies according to destination. Please request a quote
For currency conversion (OANDA) click here
Payment via PayPal welcome! Our Paypal account is under my email address: magellan@kkohki.com

Sorry, no shopping basket... For orders and inquiries Please email me (Barry Gooley) directly

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 Accessories For Vixen PORTA / PORTA II

Slewing Handle : "New Guide Handle"

Carry Bag : "PORTA Bag"

The Vixen PORTA, and newest model PORTA II alt-azimuth mounts, have taken Japan by storm and I hear that they are hot sellers all over the world. And no wonder; the PORTA mount carries a decent payload up to about 5~6, maybe 7Kg, OTAs attach easily to it with the now nearly universal Vixen dovetail plate, it has competent dual axis slow motion handles, and comes complete with a very decent height adjustable aluminum tripod, all for a quite reasonable price. And it`s rather pretty too. But we did notice one aspect of the PORTA mount that, in use, sometimes proves to be amazingly annoying .....





Aiming your PORTA mounted OTA around the sky usually means grabbing the focuser or star diagonal and then using this "handle" to point your scope. This often results in twisting the star diagonal out of alignment, getting gear grease on fingers or even having the star diagonal+eyepiece combination fall off onto the hard ground below....Yikes! At any rate, the usual method is, oh, so, well,... inelegant....And perhaps not very accurate either. And certainly not convenient....

Instead of grabbing and then man-handling the focuser, the simple addition of a robust handle to the altitude axis of the PORTA removes all this lack of finesse with a quick and easy installation. The "New Guide Handle", designed specifically for use on PORTA mounts, has a foam covered grip on the end that keeps fingers warm, and lets you become the true master of your trusty PORTA mount ;-)

Our "New Guide Handle", for both PORTA and PORTA II mounts, attaches in about 5 easy minutes, and the necessary tools are included with your PORTA mount as it comes from Vixen. Attachment involves removing the dovetail saddle plate on the altitude axis, slipping it over the New Guide Handle, then rebolting the combination back on to the altitude axis, a very simple procedure that is also kinda fun to perform. Highly recommended for all PORTA users!!

1) Gather your implements from under the rubber cover of your PORTA`s azimuth axis

2) Use this hex wrench to loosen the screws attaching the saddle plate to the altitude axis.

3) Get your New Guide Handle in hand, along with the included attachment screws.

4) Line up the holes in the saddle plate with the New Guide Handle and insert the screws

5) With the same hex wrench, screw the saddle plate, with the New Guide Handle sandwiched between it and the mount, back onto the altitude axis 6) Installation completed in 5 minutes or less! Make pointing of your PORTA easy, intuitive, accurate and for the first time, elegant!

The PORTA Bag

For both PORTA and PORTA II mounts, we also offer a PORTA specific carry bag that perfectly conforms to the hump of the alt-azimuth head assembly, and includes an inner pocket for holding the plastic parts tray from between the tripod legs. Rugged materials and strong zippers will keep your PORTA safe for a lifetime and it sure makes transporting and storing your PORTA mount a cinch. One of our most popular items in the Japanese market, this carry bag can also contain other makers` tripods or even complete telescope OTAs like a TAK FC125 (without removing the finder).

PORTA BAG
Internal pocket for the parts tray
PORTA mount inside

  Part #
  Part Name
  Price
nhg
New Guide Handle for PORTA/PORTA II
4,800 yen
bag-porta
Carry bag for PORTA/PORTA II
6,800 yen

We ship via fast EMS Airmail to anywhere in the world!
to ship you 1 ~ 2 New Guide handle
Please add 2,000 Yen to your order
to ship you 1 Carry Bag
Please add 3,000 Yen to your order
Or 3,000 yen to ship you both the PORTA New Guide Handle and Carry bag together in same order
For currency conversion (OANDA) click here
Payment via PayPal welcome! Our Paypal account is under my email address: magellan@kkohki.com

Sorry, no shopping basket... For orders and inquiries Please email me (Barry Gooley) directly


Eyepiece Bolt Cases

Tough screw-on plastic bolt covers protect eyepieces from dust, grime, wetness and abrasion. Choose from 3 sizes that will fit all but the latest super sized eyepieces. Low cost, light weight and with tight threads that do not come undone unless you want them to. Cheap insurance that will keep your eyepieces individually protected, probably forever, with no maintenance. Will also accept labeling with an oil based felt pen. (Water resistant but not waterproof- not to be immersed in water with your precious eyepieces inside!). These bolt cases probably have a thousand other uses as well. How about using them to store nuts and bolts, coins, gold dust, trail mix or even your favorite coffee beans.... ; - )

 

 
 
     
 

  Part #
  Part Name
  Inside dimensions
  Price
NEC1
Screw on Bolt Case "Large"
 64mm x   115mm
580 yen
NEC2
Screw on Bolt Case "Medium"
 48mm x   102mm
380 yen
NEC0
Screw on Bolt Case "Small"
 40mm x    80mm
280 yen
For currency conversion (OANDA) click here

Sorry, no shopping basket... For orders and inquiries Please email me (Barry Gooley) directly

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