Would Nikon release new telescopes?

RichA wrote:
Real ones, like they did in the 1960's, not spotting scopes?

http://babelfish.yahoo.com/translate...rUrl=Translate

"Eyepiece"? that's awfully big for an eyepiece...

On 26/08/2010 17:39, Paul Furman wrote:
RichA wrote:
Real ones, like they did in the 1960's, not spotting scopes?

http://babelfish.yahoo.com/translate...rUrl=Translate


"Eyepiece"? that's awfully big for an eyepiece...

It is 102 degree apparent field of view which is huge and requires a lot
of glass to implement it. Until fairly recently 84 degree was widest and
many common eyepieces are only 44 degree AFOV.

I can't see Nikon bothering to reenter this game with the likes of
Vixen, Takahashi, Pentax and Borg already having sewn up the domestic
market across all the price range. There isn't room for another player.

Regards,
Martin Brown

Martin Brown wrote:
On 26/08/2010 17:39, Paul Furman wrote:
RichA wrote:
Real ones, like they did in the 1960's, not spotting scopes?

http://babelfish.yahoo.com/translate...rUrl=Translate

"Eyepiece"? that's awfully big for an eyepiece...

It is 102 degree apparent field of view which is huge and requires a lot
of glass to implement it. Until fairly recently 84 degree was widest and
many common eyepieces are only 44 degree AFOV.

Can you explain more? FOV on which end? Wouldn't you need a huge
telescope too? This gives me somewhat of a clue, in the reviews:
http://www.hayneedleshopping.com/tel...=21-73110806-2

Nikon is still very much into microscopes and I'd have thought eyepieces
are similar for telescopes.


I can't see Nikon bothering to reenter this game with the likes of
Vixen, Takahashi, Pentax and Borg already having sewn up the domestic
market across all the price range. There isn't room for another player.

Regards,
Martin Brown

On 26/08/2010 19:59, Paul Furman wrote:
Martin Brown wrote:
On 26/08/2010 17:39, Paul Furman wrote:
RichA wrote:
Real ones, like they did in the 1960's, not spotting scopes?

http://babelfish.yahoo.com/translate...rUrl=Translate


"Eyepiece"? that's awfully big for an eyepiece...

It is 102 degree apparent field of view which is huge and requires a lot
of glass to implement it. Until fairly recently 84 degree was widest and
many common eyepieces are only 44 degree AFOV.

Can you explain more? FOV on which end? Wouldn't you need a huge
telescope too?

No not really. You need a 2" diameter eyepiece tube to use them.

There is a rule of thumb that magnification can range from about 3.5 to
40x per inch of aperture. These super wide eypieces allow you to observe
a bigger chunk of sky at a higher magnification.

When you look into the eyepiece you see an apparent field of view that
extends to 100 degrees across. This is wider than most people can
concentrate on! I haven't tried an eyepiece in this new class, but then
I don't really like the 84 degree ones that much.

High magnification improves contrast in that the stars stay essentially
unresolved points and the light pollution gets spread out. I have one 84
degree AFOV eyepiece and a couple of high end Pentax 70 degree ones. I
much prefer the latter.

The fashion is for the "space walk" experience and these very expensive
eyepieces are impressive to look through even if they are jam jar sized
or bigger. I find that some of the widest ones there is enough
distortion to be distracting. Televue Panoptics and the Pentax series
are my personal favourites although TV Naglers have their fans.

http://www.televue.com/engine/TV3_page.asp?id=2

Worth looking at the weights! You do need a fairly hefty telescope mount
and focuser. Then there are loads of clones of the designs.

This gives me somewhat of a clue, in the reviews:
http://www.hayneedleshopping.com/tel...=21-73110806-2

Nikon is still very much into microscopes and I'd have thought eyepieces
are similar for telescopes.

There is even more emphasis on light transmission and ghosting for astro
optics. You tend to be looking at a mostly dark field with a very bright
planetary disk in it in the most demanding situation. And with some
eyepieces the reflection off your eyeball can be a distraction!

Nikon still have parts of the microscope business, but I honestly can't
see them going back into telescope making now.

Regards,
Martin Brown

"RichA" wrote:

Leave no niche unturned.

A perfect example of a fatally flawed business model.

--
Mike Benveniste -- (Clarification Required)
Its name is Public opinion. It is held in reverence. It settles
everything. Some think it is the voice of God. -- Mark Twain

Twibil wrote:
Martin Brownwrote:
Paul Furman wrote:

Can you explain more? FOV on which end? Wouldn't you need a huge
telescope too?

No not really. You need a 2" diameter eyepiece tube to use them.

...Some wide-angle telescope eyepieces are 1 1/4", some are 2",
and a few can go either way.

http://www.telescope.com/control/tel...cope-eyepieces

Interesting.

I'm trying to learn about microscopes, which don't really go over a 22mm
image circle AFAIK (less than an inch), although you can magnify more
with extension to make it fit, that's not what the objectives are
designed for and doesn't necessarily work. Microscopes set up for
photography typically need some extra glass to fill the frame and if you
put an APS DSLR atop a trinocular head without added glass (best), then
the binocular eyepiece view won't show the full frame that the camera
sees. It seems you'd need some kind of special objective to make it work
with these wide eyepieces, or probably even that wouldn't work due to
mechanical obstructions because they just aren't designed for that size.

There are specialized macro lenses and big bellows rigs for larger
formats but not with a microscope viewfinder included. Live view solves
that except that you either need to stand up & look over the rig to see
the LCD or shoot tethered and that mostly doesn't seem to work with live
view. Perhaps two of those telescope eyepieces could be used with a 45
degree prism where you swap out the prism & eyepiece for the camera. Or
just one straight on for a horizontal bellows rig.

For full frame 35mm:
43mm image circle = 1.7 inches
-so 1-1/4" won't make it but 2" will.

On 30/08/2010 03:24, Paul Furman wrote:
Twibil wrote:
Martin Brownwrote:
Paul Furman wrote:

Can you explain more? FOV on which end? Wouldn't you need a huge
telescope too?

No not really. You need a 2" diameter eyepiece tube to use them.

...Some wide-angle telescope eyepieces are 1 1/4", some are 2",
and a few can go either way.

http://www.telescope.com/control/tel...cope-eyepieces


Interesting.

I'm trying to learn about microscopes, which don't really go over a 22mm
image circle AFAIK (less than an inch), although you can magnify more
with extension to make it fit, that's not what the objectives are
designed for and doesn't necessarily work. Microscopes set up for

Microscope eyepieces are typically 24.5mm and fairly high quality -
through you can buy cheap nasty ones that are supplied with Chinese
department store scopes.

The 2" fit is only needed for the longer focal lengths and wide field
combined - which allows you to see the largest possible filed of view
that the telescope can deliver. At higher magnifications the eyepiece
field stop gets progressively smaller and when it is less than 1" you
could in principle use such eyepieces with a microscope.

Most telescopes will fully illuminate 35mm film frame and the better
ones will do 6cm film. These days most people use CCD.

photography typically need some extra glass to fill the frame and if you
put an APS DSLR atop a trinocular head without added glass (best), then
the binocular eyepiece view won't show the full frame that the camera
sees. It seems you'd need some kind of special objective to make it work
with these wide eyepieces, or probably even that wouldn't work due to
mechanical obstructions because they just aren't designed for that size.

There are specialized macro lenses and big bellows rigs for larger
formats but not with a microscope viewfinder included. Live view solves
that except that you either need to stand up & look over the rig to see
the LCD or shoot tethered and that mostly doesn't seem to work with live
view. Perhaps two of those telescope eyepieces could be used with a 45
degree prism where you swap out the prism & eyepiece for the camera. Or
just one straight on for a horizontal bellows rig.

For full frame 35mm:
43mm image circle = 1.7 inches
-so 1-1/4" won't make it but 2" will.

It is only an issue when you want the lowest magnification and maximum
possible field of view of the object under study. There can be some real
mileage in having a higher magnification wider apparent field of view in
astronomy since sky brightness goes down whilst unresolved stars remain
points of light (ie visual contrast is improved). I don't think this
would hold in microscopy except possibly for fluorescence work.

Regards,
Martin Brown

Martin Brown wrote:
On 30/08/2010 03:24, Paul Furman wrote:
Twibil wrote:
Martin Brownwrote:
Paul Furman wrote:

Can you explain more? FOV on which end? Wouldn't you need a huge
telescope too?

No not really. You need a 2" diameter eyepiece tube to use them.

...Some wide-angle telescope eyepieces are 1 1/4", some are 2",
and a few can go either way.

http://www.telescope.com/control/tel...cope-eyepieces



Interesting.

I'm trying to learn about microscopes, which don't really go over a 22mm
image circle AFAIK (less than an inch), although you can magnify more
with extension to make it fit, that's not what the objectives are
designed for and doesn't necessarily work. Microscopes set up for

Microscope eyepieces are typically 24.5mm and fairly high quality -
through you can buy cheap nasty ones that are supplied with Chinese
department store scopes.

The 2" fit is only needed for the longer focal lengths and wide field
combined - which allows you to see the largest possible filed of view
that the telescope can deliver. At higher magnifications the eyepiece
field stop gets progressively smaller and when it is less than 1" you
could in principle use such eyepieces with a microscope.

Most telescopes will fully illuminate 35mm film frame and the better
ones will do 6cm film. These days most people use CCD.

photography typically need some extra glass to fill the frame and if you
put an APS DSLR atop a trinocular head without added glass (best), then
the binocular eyepiece view won't show the full frame that the camera
sees. It seems you'd need some kind of special objective to make it work
with these wide eyepieces, or probably even that wouldn't work due to
mechanical obstructions because they just aren't designed for that size.

There are specialized macro lenses and big bellows rigs for larger
formats but not with a microscope viewfinder included. Live view solves
that except that you either need to stand up & look over the rig to see
the LCD or shoot tethered and that mostly doesn't seem to work with live
view. Perhaps two of those telescope eyepieces could be used with a 45
degree prism where you swap out the prism & eyepiece for the camera. Or
just one straight on for a horizontal bellows rig.

For full frame 35mm:
43mm image circle = 1.7 inches
-so 1-1/4" won't make it but 2" will.

It is only an issue when you want the lowest magnification and maximum
possible field of view of the object under study. There can be some real
mileage in having a higher magnification wider apparent field of view in
astronomy since sky brightness goes down whilst unresolved stars remain
points of light (ie visual contrast is improved). I don't think this
would hold in microscopy except possibly for fluorescence work.

Thanks for your interesting replies. This is tough for me to learn since
I barely remember using a microscope ever, maybe in high school. I don't
care for binoculars, or headphones for that matter so I think the wider
view would be more comfortable, less eye strain. Here's a couple tidbits
I came across on this topic of wide eyepieces in microscopes:

http://www.olympusmicro.com/primer/faq.html
Eyepieces, in addition to having the magnification inscribed, are marked
20, or 22, or 26.5. What do these numbers mean?

The designation is the field number of the eyepiece. The higher the
field number of the eyepiece being used with a particular objective, the
more specimen area will appear in the field of view. The diameter of the
field of view, in millimeters, is calculated by dividing the field
number of the eyepiece by the magnification of the objective. (For
example, with a 10x objective and an eyepiece with a field number of 22,
the diameter of the field of view would be 2.2 millimeters) For many
microscopists, e.g. hematologists, it saves time to be able to see more
of the specimen at a given time. Eyepieces with a field number of 26.5
are called super-wide eyepieces.

http://www.mitutoyo.com/pdf/US4197-378.pdf
Super-wide field of view eyepiece
Being equipped with an eyepiece with field number 30, the
highest in its class, allows observation of a wide view-field to
greatly reduce eye fatigue.