My father recently passed away and he had a Bausch and Lomb Critereon 4000 which I now have. I am not at even an amateur and can't figure out how to even make this telescope work. Hoping someone out there might have some advice as I've searched online for a manual online and haven't found one. Many thanks.

On Saturday, August 27, 2022 at 8:30:24 AM UTC-7, wheffe...@gmail.com wrote:
> My father recently passed away and he had a Bausch and Lomb Critereon 4000 which I now have. I am not at even an amateur and can't figure out how to even make this telescope work. Hoping someone out there might have some advice as I've searched online for a manual online and haven't found one. Many thanks.

https://www.ebay.com/itm/Instruction-manual-for-Bausch-Lomb-Criterion-4000-Telescope/155136581235?mkcid=1&mkrid=711-53200-19255-0&campid=5338722076&toolid=10050&pageci=88ee9a39-2ebc-4f61-8f7e-b5c112ef3633&redirect=mobile

On Saturday, August 27, 2022 at 9:02:28 AM UTC-7, palsing wrote:
> On Saturday, August 27, 2022 at 8:30:24 AM UTC-7, wheffe...@gmail.com wrote:
> > My father recently passed away and he had a Bausch and Lomb Critereon 4000 which I now have. I am not at even an amateur and can't figure out how to even make this telescope work. Hoping someone out there might have some advice as I've searched online for a manual online and haven't found one. Many thanks.

> https://www.ebay.com/itm/Instruction-manual-for-Bausch-Lomb-Criterion-4000-Telescope/155136581235?mkcid=1&mkrid=711-53200-19255-0&campid=5338722076&toolid=10050&pageci=88ee9a39-2ebc-4f61-8f7e-b5c112ef3633&redirect=mobile

A post on Cloudy Nights claims that a Meade 2045 may thr same telescope rebranded...

https://www.manualslib.com/manual/100879/Meade-2045.html

On Saturday, August 27, 2022 at 8:30:24 AM UTC-7, wheffe...@gmail.com wrote:
> My father recently passed away and he had a Bausch and Lomb Critereon 4000 which I now have. I am not at even an amateur and can't figure out how to even make this telescope work. Hoping someone out there might have some advice as I've searched online for a manual online and haven't found one. Many thanks.

You have to look into the rear end of the telescope.
Make sure to put an eyepiece in it first.
Pointed on the Moon, focus and see our neighbor planet in full glory!

On Saturday, August 27, 2022 at 9:30:24 AM UTC-6, wheffe...@gmail.com wrote:
> My father recently passed away and he had a Bausch and Lomb Critereon 4000 which I now have. I am not at even an amateur and can't figure out how to even make this telescope work. Hoping someone out there might have some advice as I've searched online for a manual online and haven't found one. Many thanks.

Well, the good news is that the Bausch and Lomb is very similar to zillions of other
Schmidt-Cassegrain telescopes out there, and so making it work would be similar to
how you make other telescopes work.

It's got a big lens cap - four inches in diameter - on the front part that you would point
at stars or planets or the Moon. You would need to take it off.

The back side should have a small L-shaped thing sticking out. You need to put a
1 1/4" astronomical eyepiece in it. No doubt you've also inherited a few of those along
with the telescope.

At this point, the telescope will "work" - you will be able to point it at stuff, and see it bigger.

Now there's other stuff you need to know. The telescope is... the round part. But it's held
by two arms on a squat cylindrical base.

One of the circular things on those arms near the telescope has a metal rod sticking out of it
with a knurled knob. You can turn that to unlock the ability to tilt the telescope up and
down.

The two arms are on a round thing on that squat cylindrical base. There's a small knob there
that if turned lets you unlock the ability to turn the telescope from side to side.

Now, why bother to lock the telescope? Because there's more!

On the bottom of that cylindrical base, there's a socket with three prongs in it, similar to what
you will find for the power cord of a computer. That cylindrical base has a *motor* in it.

Maybe the telescope is already on a tripod. And it's attached by screws to a flap that ends
in a ring that has an obvious adjustment in some curved long holes in a boxy base that is
attached by big wing nuts to the flat tabletop of the tripod.

That thing between the tripod and your telescope is called an "equatorial wedge". The
adjustment in those long holes should not be disturbed, unless you move to another city:
it corresponds to your latitude.

The idea is that the direction towards which your telescope is tilted by this wedge
ought to be North. Making it so is called "polar alignment". Do that...

and then unlock those two knurled knobs, and point your telescope at what you want to look
at,

then lock the knobs,

and plug the telescope's cylindrical base into a wall socket,

and the telesope will be turned by the clock motor at the rate of one rotation every 23 hours,
56 minutes, and 4 seconds. The result of that is, if you've chosen to look at some stars, the
telescope will follow them perfectly. Planets and the moon, not quite as well, but still pretty
good.

Oh, and don't ever try and look at the Sun through this very powerful telescope, as that's
dangerous.

John Savard

On Saturday, August 27, 2022 at 11:13:25 PM UTC-6, Quadibloc wrote:

> The back side should have a small L-shaped thing sticking out. You need to put a
> 1 1/4" astronomical eyepiece in it. No doubt you've also inherited a few of those along
> with the telescope.

Oh, and I forgot one other very important detail. There's a knob next to the round
ring holding that L-shaped thing on to the back of the telescope. That's the knob
you turn to focus the telescope; you'll need to do that when you put a different
eyepiece in from the one with which it was last used.

John Savard

On Saturday, August 27, 2022 at 11:16:42 PM UTC-6, Quadibloc wrote:

> Oh, and I forgot one other very important detail.

There is something else I forgot, although it is more advanced.

You will notice that there is a long refracting telescope (a plain telescope
that has a lens in front, and doesn't use any mirrors) held by three bolts
(or machine screws, if you prefer) in a ring that's attached to the metal
back of the telescope.

This telescope has a low magnification compared to the telescope it's
attached to. It's probably obvious that its purpose is to help you find the
direction to point your telescope to look at what you want to look at,
and indeed, it's called a finderscope.

On the Bausch and Lomb Criterion 4000 telescope that I used to own,
those three screws didn't hold the finderscope still very well. So I made
a triangular thing with a round indentation at the top to hold the far
end of the finderscope still. I also put tape around both the finderscope
and the main telescope with that spacer holding them apart.

Then I took the whole telescope, tripod and all, into the bathroom where
I had a big mirror. I pointed the telescope straight at the mirror. Without
putting an eyepiece in the telescope, I looked through the hole in the
L-shaped thing, so that I had the telescope pointed exactly dead on
towards the mirror, perpendicular to its surface.

Then I looked through the finderscope, and adjusted the three screws so
that the finderscope was looking straight at its own reflection.

That way, the center of the field of view of the finderscope was exactly where
the big telescope was looking. That was helpful.

And the eyepiece lens of the finderscope is in a housing that can be rotated,
this is how the finderscope is focused if need be.

John Savard

On Saturday, August 27, 2022 at 11:30:24 AM UTC-4, wheffe...@gmail.com wrote:
> My father recently passed away and he had a Bausch and Lomb Critereon 4000 which I now have. I am not at even an amateur and can't figure out how to even make this telescope work. Hoping someone out there might have some advice as I've searched online for a manual online and haven't found one. Many thanks.

---
As long as your telescope looks something like this, without anything missing, it should work just fine:

https://thumbs.worthpoint.com/zoom/images2/1/0414/17/bausch-lomb-criterion-4000-four-inch_1_c4f9b95c7fb13d15a693d8677ed9dfff.jpg

It's just a matter of aim and focus. Start with the Moon.

(BUT DO NOT EVER LOOK AT THE SUN!)

After you get good at looking at the Moon, try aiming at some planets.

(The manual will have some useful details, mostly about the care of the telescope.)

His link is showing the right telescope. I had forgotten about the tabletop
legs that came with it.

Instead, I described one with a full wedge, such as is shown here
https://i1.wp.com/rainydaymagazine.com/wp/wp-content/uploads/2016/07/ScopeOnWedge_Left.jpg
from the page
http://rainydaymagazine.com/wp/2016/07/17/a-second-life-for-a-bausch-lomb-criterion-4000-sct/

and here
https://www.cloudynights.com/gallery/image/46551-bausch-lomb-4000/

John Savard

On Saturday, August 27, 2022 at 11:13:25 PM UTC-6, Quadibloc wrote:

> One of the circular things on those arms near the telescope has a metal rod sticking out of it
> with a knurled knob. You can turn that to unlock the ability to tilt the telescope up and
> down.

I must have remembered the location of this knob wrongly.

Instead, it is on the side of one of the arms holding the two
circular things up.

John Savard

I found a link to the manual!

https://app.box.com/s/3rz6102vwul2plbmjet8jqnt4h1oxo7n

John Savard

On Sunday, August 28, 2022 at 4:55:17 PM UTC-4, RichA wrote:
> On Saturday, 27 August 2022 at 11:30:24 UTC-4, wheffe...@gmail.com wrote:
> > My father recently passed away and he had a Bausch and Lomb Critereon 4000 which I now have. I am not at even an amateur and can't figure out how to even make this telescope work. Hoping someone out there might have some advice as I've searched online for a manual online and haven't found one. Many thanks.
> Compound telescopes (telescopes with mirrors and lenses used in combination) often are of inherently high power and are difficult for beginners to use. Finding objects in the sky if you are unfamiliar with the sky
> will be essentially impossible, except for bright planets (Jupiter, Venus, Mars, Saturn) or the moon. To use an old scope like that, you'll need to learn to "star hop" (using star maps to find objects) or how to use the numbered circles on the mount. If the scope is >unmounted (field model without the fork mount) then it'll be on a camera tripod.

\\\\\\\\\\\\\\\\\

That's overstating the case a little.

The telescope has a 1200mm focal length, giving 40x with a 30mm eyepiece. A one-degree field of view should be obtainable, even with a slightly shorter eyepiece.

The more serious problem is the lack of a good finderscope. The one that seems to have been the standard for this scope makes the old "5x24" seem luxurious. A Telrad or red-dot finder might work better or maybe not.

On Tuesday, August 30, 2022 at 3:38:11 AM UTC-4, RichA wrote:
> On Sunday, 28 August 2022 at 20:07:52 UTC-4, W wrote:
> > On Sunday, August 28, 2022 at 4:55:17 PM UTC-4, RichA wrote:
> > > On Saturday, 27 August 2022 at 11:30:24 UTC-4, wheffe...@gmail.com wrote:
> > > > My father recently passed away and he had a Bausch and Lomb Critereon 4000 which I now have. I am not at even an amateur and can't figure out how to even make this telescope work. Hoping someone out there might have some advice as I've searched online for a manual online and haven't found one. Many thanks.
> > > Compound telescopes (telescopes with mirrors and lenses used in combination) often are of inherently high power and are difficult for beginners to use. Finding objects in the sky if you are unfamiliar with the sky
> > > will be essentially impossible, except for bright planets (Jupiter, Venus, Mars, Saturn) or the moon. To use an old scope like that, you'll need to learn to "star hop" (using star maps to find objects) or how to use the numbered circles on the mount. If the scope is >unmounted (field model without the fork mount) then it'll be on a camera tripod.
> > \\\\\\\\\\\\\\\\\
> >
> > That's overstating the case a little.
> >
> > The telescope has a 1200mm focal length, giving 40x with a 30mm eyepiece. A one-degree field of view should be obtainable, even with a slightly shorter eyepiece.
> >
> > The more serious problem is the lack of a good finderscope. The one that seems to have been the standard for this scope makes the old "5x24" seem luxurious. A Telrad or red-dot finder might work better or maybe not.
> Height of finder above the scope makes it a bit difficult to use. Red dot finders are fine for objects you can see naked eye.

\\\\\\\\

The priority here is to get the scope aimed and focused at something, anything, in the night sky, as a first step.

If the views inspire the OP, then he can either make some improvements on the existing scope as he learns about astronomy, or he can proceed to some telescope that is more powerful.

Right now, we have practically no information on which to judge the situation.

On Tuesday, August 30, 2022 at 6:42:20 AM UTC-6, W wrote:

> If the views inspire the OP, then he can either make some improvements on the existing scope as he learns about astronomy, or he can proceed to some telescope that is more powerful.

And, I must admit, while I answered his question about how to use
it, I gave no information at all about that part of it. So here is what
was missing... if he is still watching this thread.

It is a more powerful telescope than the cheap ones often sold in
stores, but it still is not the most powerful telescope out there.

If you also have eyepieces, they will have numbers on them. The
number on an eyepiece is usually its focal length in millimeters.

The focal length of a Bausch and Lomb Criterion 4000 telescope is
1200 millimeters - its aperture is 100 millimeters, and it is an f/12
telescope. (Yes, f/12 means the same thing as it does for a camera
lens.)

The magnification of a telescope is the focal length of the telescope
divided by that of the eyepiece. So, if you use an eyepiece bearing the
number "10" on your telescope, you will magnify 120 times.

Using an eyepiece bearing the number "5", if you have one, will cause
the telescope to magnify about as much as is reasonable for a telescope
with a 4-inch aperture. If you look at Jupiter or Saturn with the telescope
at that magnification, they will be fairly small, but you will be able to see
them as disks with surface detail. You will be able to see the rings of Saturn
with your own eyes.

John Savard

On Tuesday, August 30, 2022 at 5:59:56 PM UTC-4, Quadibloc wrote:
> On Tuesday, August 30, 2022 at 6:42:20 AM UTC-6, W wrote:
>
> > If the views inspire the OP, then he can either make some improvements on the existing scope as he learns about astronomy, or he can proceed to some telescope that is more powerful.
> And, I must admit, while I answered his question about how to use
> it, I gave no information at all about that part of it. So here is what
> was missing... if he is still watching this thread.

It is quite likely that he isn't watching and possibly won't ever return.
Once he has access to the manual, he can, maybe, determine which parts are missing, such as eyepieces, diagonals, finders, etc, and what the various buttons, knobs and clamps do.

Frankly, I think the manual was rather badly written and muddy-looking.

The "accessories manual" looked much better.

On Tuesday, August 30, 2022 at 6:54:36 PM UTC-6, W wrote:

> It is quite likely that he isn't watching and possibly won't ever return.

I fear that as well.

> Frankly, I think the manual was rather badly written and muddy-looking.

That could be. I didn't write it, I just found it. At least it has a
nice picture of Isaac Asimov in it.

John Savard

On Wednesday, August 31, 2022 at 12:51:32 AM UTC-4, Quadibloc wrote:
> On Tuesday, August 30, 2022 at 6:54:36 PM UTC-6, W wrote:
>
> > It is quite likely that he isn't watching and possibly won't ever return.
> I fear that as well.
> > Frankly, I think the manual was rather badly written and muddy-looking.
> That could be. I didn't write it, I just found it. At least it has a
> nice picture of Isaac Asimov in it.

The manual does NOT mention a part that was missing on an example of this model that I encountered at a flea market.

Should that same part be missing on the OP's telescope, he will still be left scratching his head about what to do.

He could take the thing to a local astronomy club meeting and hope that the club has a resident B&L guru lurking about.

As for the unit that I saw, the asking price was too high considering that ALL of the accessories were missing, including the power cord. The staff had no idea where that stuff was or if it was even on-site.

I was a teen when this telescope first came out. I noticed it while
shopping with my parents in a store called Best (no relation to today's
Best Buy). Anyway, I think the price at the time was either $299 or
$399. I was still using my 20x60 binoculars to examine the heavens, but
I was always on the lookout for a telescope and a half decent one.

I was tempted to ask my father if I could have it as an upcoming
Christmas gift even though I knew it would exceed my Christmas budget
limit of $300. However, I never stuck up the nerve to ask him. I was
still too young to work summers a the time, so that option was
definitely out. So I used to go over to this telescope in the display
case every time we went to Best. I remember there was an advertisement
flyer inside the case with the scope and it was the page from the manual
with Issac Asimov. I'd read that every time.

Finally, one day we shopped and the scope was gone. So ended that teen
dream. It would be about three years later when I would eye Coulter's
10.1" Dob at I think around the same price they wanted for the
Criterion. This time, I was working summers and what was the first
thing I blew my first summer payment on but the Dob! So an order was
placed in the fall and it took until spring to arrive by Yellow Freight
I believe.

Along with my Telrad finder and Sky Atlas 2000 charts, I spent plenty of
nights in my backyard with the Dob. Since the Dob had no clock drive or
setting circles, everything had to be found by star hopping. At the
time my backyard was a yellow zone, so there was plenty to be seen. I
remember one of my first treasures was seeing Barnard's Loop in Orion.
I had never seen this before, or since actually visually! Eventually
the Dob was sold after an ad was placed in a local publication.

Fast forward about 25 years and I acquired a used Meade 8" SCT and also
a Celestron Nexstar SE mount. The two were paired together and in one
night from a dark sky site, I saw more in six hours then I ever did star
hopping all those summers with the Dob. Even at home, the same home I
grew up in and now an orange zone, I was still able to see more in one
night than any of the prior Dob nights. How technology sure changes and
how sometimes we reap the benefits.

On Wednesday, August 31, 2022 at 8:39:52 AM UTC-4, Al Stuill wrote:
> I was a teen when this telescope first came out. I noticed it while
> shopping with my parents in a store called Best (no relation to today's
> Best Buy). Anyway, I think the price at the time was either $299 or
> $399.

[[edited]]

> Finally, one day we shopped and the scope was gone. So ended that teen
> dream.

You probably did not miss anything, given the price of the telescope.

It was far too complicated for what it did.