Disassembling Rubinar 10/1000
Winstone
I'd like to remove the infinity stop in my Rubinar 10/1000 to
focus at infinity with a diagonal. Anyone has saved
old archives about it or can point to new ones available. I can no
longer find information about it in Markus site or others that are no
longer
available such as http://home.t-online.de/home/mmushardt/rb4.htm
Thank you.
Winstone
Beta Persei
"Winstone" <winston...@yahoo.com> ha scritto nel messaggio
news:8b0fce02-ae49-4868...@v35g2000pro.googlegroups.com...
You may try this:
http://xoomer.virgilio.it/jimi52/mto.htm
It is written in Italian, but Google should not have too many troubles in
translating it....
Best luck,
--------
Beta Persei
45° 35' N
08° 51' E
remove "_nospam" to reply
Winstone
> "Winstone" <winstonewar...@yahoo.com> ha scritto nel messaggionews:8b0fce02-ae49-4868...@v35g2000pro.googlegroups.com...
>
> > Hi,
>
> > I'd like to remove the infinity stop in my Rubinar 10/1000 to
> > focus at infinity with a diagonal. Anyone has saved
> > old archives about it or can point to new ones available. I can no
> > longer find information about it in Markus site or others that are no
> > longer
>
> > Thank you.
>
> > Winstone
>
> You may try this:http://xoomer.virgilio.it/jimi52/mto.htm
> It is written in Italian, but Google should not have too many troubles in
> translating it....
> Best luck,
> --------
> Beta Persei
> 45° 35' N
> 08° 51' E
>
> remove "_nospam" to reply
MTO is not similar to the Rubinar. I have both. It's like trying to
fix the
male anatomy by analyzing female anatomy. One can make the MTO
focus past infinity by simply unscrewing a screw but with the Rubinar,
6 screws have to be removed and many manuevers to remove
the stop. I don't know how. Old sites don't show up. Markus email
doesn't work. He has article in his old website on how to disassemble
it and remove the article in his new website. Anyone has saved his
old website and can share the old article?
Win
Beta Persei
>MTO is not similar to the Rubinar. I have both.
Ok, I guessed thet were similar.
Have you already found this one?
http://coldlake0.tripod.com/rubinarT.html
Clear skies,
Winstone
> "Winstone" <winstonewar...@yahoo.com> ha scritto nel messaggionews:8dd4992f-7d22-44b0...@j18g2000prm.googlegroups.com...
>
> >MTO is not similar to the Rubinar. I have both.
>
> Ok, I guessed thet were similar.
> Have you already found this one?http://coldlake0.tripod.com/rubinarT.html
Yes. That's where I found out about the site
http://home.t-online.de/home/mmushardt/rb4.htm
which has more complete instructions.
Also it seems the older Rubinar has shorter
rubber focusing sleeve. Mine is like this.
http://kremlinoptics.com/catalog/item/rubinar_10_1000_telephoto_lens.html
Notice the newer one has longer rubber sleeve.
Wonder where I could even locate the screw
to remove the focusing collar. Anyone?
Win
Bhogi
>
> > Ok, I guessed thet were similar.
> > Have you already found this one?http://coldlake0.tripod.com/rubinarT.html
>
> which has more complete instructions.
>
> Also it seems the older Rubinar has shorter
> rubber focusing sleeve. Mine is like this.
>
>
> Notice the newer one has longer rubber sleeve.
> Wonder where I could even locate the screw
> to remove the focusing collar. Anyone?
>
> Win
Here are my notes from when I finally managed to figure out how to do
it (4 years ago).
Take photos of the process!
- first unscrew the "shoe" of the "mounting ring"
- unscrew the 3 screws inside the "mounting ring", rotate the ring to
find them
- remove the "mounting ring" towards the camera mount
- remove the rubber grip and unscrew the 3 screws
- slip the focusing ring towards where the "mounting ring" was
- now unscrew the locking screws of the aluminum ring, correct
infinity focus etc.
- screw everything back on in the reverse order
Before putting the ring back on:
- lock the inner ring of the mounting ring so one hole for the
screw aligns with the hole, where the "shoe" comes
- put the ring back on the lens, so this hole aligns with one of
the holes on the oposite side of the lens where the focusing line is
(if you don't do this, the focusing line will never lock on top of
the lens - 4 locking positions and 3 screws)
Hope it helps.
It realy isn't all that complicated when you have the lens before you.
Winstone
>
> - Show quoted text -
Hi, There seems to be 2 kinds of Rubinar, the new one has
full rubber sleeve. See:
http://kremlinoptics.com/catalog/item/rubinar_10_1000_telephoto_lens.html
The old one has shorter rubber sleeve. See:
http://coldlake0.tripod.com/rubinarT.html
Which one do you own? In the shorter sleeve. You
remove the screw near the rubber sleeve first
as mentioned in the instructions.
The shoe of the mounting ring is the one that
is connected to the tripod?
Also it is the mentioned in the following that there
are bearings which can get out and impossible
to fix. See near the bottom of:
http://www.rugift.com/photocameras/rubinar_lenses_with_various_cameras.htm
"It is not recommend doing the adjustment to the
1000 mm lens because of those little ball bearings
which fall out and are impossible to get back in."
What bearings are they talking about?
Thanks.
Win
Bhogi
>
> The old one has shorter rubber sleeve. See:
>
> http://coldlake0.tripod.com/rubinarT.html
>
> Which one do you own? In the shorter sleeve. You
> remove the screw near the rubber sleeve first
> as mentioned in the instructions.
>
> The shoe of the mounting ring is the one that
> is connected to the tripod?
>
> Also it is the mentioned in the following that there
> are bearings which can get out and impossible
> to fix. See near the bottom of:
>
>
> "It is not recommend doing the adjustment to the
> 1000 mm lens because of those little ball bearings
> which fall out and are impossible to get back in."
>
> What bearings are they talking about?
>
> Thanks.
>
> Win
Here's a picture of my lens with the stop removed.
http://www.ejarm.com/rubinar1000.jpg
I think I have a new version.
I purchased the lens from rugift, and those notes were mailed to them
to put on the page because their instructions were totaly misleading.
They didn't do anything.
Basicaly I had to unscrew everything to find out what to do.
I also found the first page but it was useless for me.
As you can see from my picture no balls fell out. They are safely in
the mounting ring, which is a large ball bearing for rotating the
camera around the tripod mount (the shoe, hehe).
Compare your lens with my picture and if it looks the same I think you
can do it.
Winstone
>
> > > Ok, I guessed thet were similar.
> > > Have you already found this one?http://coldlake0.tripod.com/rubinarT.html
>
> > Yes. That's where I found out about the sitehttp://home.t-online.de/home/mmushardt/rb4.htm
> > which has more complete instructions.
>
> > Also it seems the older Rubinar has shorter
> > rubber focusing sleeve. Mine is like this.
>
> >http://kremlinoptics.com/catalog/item/rubinar_10_1000_telephoto_lens....
>
> > Notice the newer one has longer rubber sleeve.
> > Wonder where I could even locate the screw
> > to remove the focusing collar. Anyone?
>
> > Win
>
> I think I have a new version.
Where is the rubber grip in your picture? Mine
looks exactly like this:
http://www.rugift.com/photocameras/rubinar_1000_lens_for_canon_eos.htm
Does yours look exactly like it too (it's closeup).
Also my serial no. is 40211 while yours is only 00249. There
are 40,000 units after yours so maybe you got an ancient
model?
Look at the new model which I got which seems not
identical to yours (I haven't seen yours fully assembled
Hope you can share picture of yours fully assembled
so I can note the difference between our models if
there is).
> Here are my notes from when I finally managed to figure out how to do
> it (4 years ago).
>
> Take photos of the process!
>
> - first unscrew the "shoe" of the "mounting ring"
> - unscrew the 3 screws inside the "mounting ring", rotate the ring to
> find them
> - remove the "mounting ring" towards the camera mount
> - remove the rubber grip and unscrew the 3 screws
I can't remove the rubber grip because it's stuck between
the body. See again picture at:
http://www.rugift.com/photocameras/rubinar_1000_lens_for_canon_eos.htm
Yours doesn't seem to have any textured rubber grip.
> - slip the focusing ring towards where the "mounting ring" was
> - now unscrew the locking screws of the aluminum ring, correct
> infinity focus etc.
Is the focusing ring also the aluminum ring? or different?
Thanks.
Win
> - screw everything back on in the reverse order
>
> Before putting the ring back on:
> - lock the inner ring of the mounting ring so one hole for the
> screw aligns with the hole, where the "shoe" comes
> - put the ring back on the lens, so this hole aligns with one of
> the holes on the oposite side of the lens where the focusing line is
> (if you don't do this, the focusing line will never lock on top of
> the lens - 4 locking positions and 3 screws)
>
> Hope it helps.
Winstone
> I think I have a new version.
Where is the rubber grip in your picture? Mine
looks exactly like this:
http://www.rugift.com/photocameras/rubinar_1000_lens_for_canon_eos.htm
Does yours look exactly like it too (it's closeup).
Also my serial no. is 40211 while yours is only 00249. There are
40,000 units after yours.
Look at the new model which I got. Wonder if you have any
ideas how to disassemble it (noting again that it's
completely different to yours)
Win
>
> I purchased the lens from rugift, and those notes were mailed to them
> to put on the page because their instructions were totaly misleading.
> They didn't do anything.
> Basicaly I had to unscrew everything to find out what to do.
> I also found the first page but it was useless for me.
>
> As you can see from my picture no balls fell out. They are safely in
> the mounting ring, which is a large ball bearing for rotating the
> camera around the tripod mount (the shoe, hehe).
>
> Compare your lens with my picture and if it looks the same I think you
> can do it.- Hide quoted text -
Bhogi
> On Mar 25, 7:55 pm, Bhogi <bh...@siol.com> wrote:
> > Here's a picture of my lens with the stop removed.http://www.ejarm.com/rubinar1000.jpg
> > I think I have a new version.
>
> Where is the rubber grip in your picture?
It is out of the picture, sorry.
> Mine
> looks exactly like this:
>
> http://www.rugift.com/photocameras/rubinar_1000_lens_for_canon_eos.htm
Here is mine.
http://ejarm.com/rubinarall.jpg
I also made a far more practical tripod mount. The original is almost
useles for mounting on equatorial mounts.
> > Here are my notes from when I finally managed to figure out how to do
> > it (4 years ago).
>
> > Take photos of the process!
>
> > - first unscrew the "shoe" of the "mounting ring"
> > - unscrew the 3 screws inside the "mounting ring", rotate the ring to
> > find them
> > - remove the "mounting ring" towards the camera mount
> > - remove the rubber grip and unscrew the 3 screws
>
> I can't remove the rubber grip because it's stuck between
> the body. See again picture at:
You must remove the grip to unscrew the tiny screws. It's thin and
comes off easily you just have to lift it a bit somehow. Putting it
back on is also easy.
> > - slip the focusing ring towards where the "mounting ring" was
> > - now unscrew the locking screws of the aluminum ring, correct
> > infinity focus etc.
>
> Is the focusing ring also the aluminum ring? or different?
I Think it's all aluminium. It is screwed to the front of the lens
with 3 tiny screws.
Beware, when you remove the infinity stop you can focus to about 1m,
nearer than that the front might come off and you'll have difficulty
putting it back correctly.
If you feel adventurous you might like to unscrew the front after all
and clean the threads of the sticky grease and use some lighter
grease. The action will be much lighter. I used lithium grease but I
hear it's not good for optics. There is still no fogging of the optics
after 4 years.
>
> Thanks.
>
> Win
Winstone
> On 25 mar., 15:30, Winstone <winstonewar...@yahoo.com> wrote:
>
> > On Mar 25, 7:55 pm, Bhogi <bh...@siol.com> wrote:
> > > Here's a picture of my lens with the stop removed.http://www.ejarm.com/rubinar1000.jpg
> > > I think I have a new version.
>
> > Where is the rubber grip in your picture?
>
> It is out of the picture, sorry.
>
> > Mine
> > looks exactly like this:
>
> >http://www.rugift.com/photocameras/rubinar_1000_lens_for_canon_eos.htm
>
> Here is mine.http://ejarm.com/rubinarall.jpg
So it is the same as mine. I wonder what you use to
put diagonal into it? I purchased a separate m42 to
1.25" adapter that is only 0.3" length. What adapter
did you use? Hope you can take a picture without
the rear cover because I'd like to see the adapter
you use.
> I also made a far more practical tripod mount. The original is almost
> useles for mounting on equatorial mounts.
>
> > > Here are my notes from when I finally managed to figure out how to do
> > > it (4 years ago).
>
> > > Take photos of the process!
>
> > > - first unscrew the "shoe" of the "mounting ring"
> > > - unscrew the 3 screws inside the "mounting ring", rotate the ring to
> > > find them
> > > - remove the "mounting ring" towards the camera mount
> > > - remove the rubber grip and unscrew the 3 screws
>
> > I can't remove the rubber grip because it's stuck between
> > the body. See again picture at:
>
> You must remove the grip to unscrew the tiny screws. It's thin and
> comes off easily you just have to lift it a bit somehow. Putting it
> back on is also easy.
How many mm distance from the nearest boundary are the screws
located? If I can't lift all of them up. I'd just cut a portion of it.
>
> > > - slip the focusing ring towards where the "mounting ring" was
> > > - now unscrew the locking screws of the aluminum ring, correct
> > > infinity focus etc.
>
> > Is the focusing ring also the aluminum ring? or different?
>
> I Think it's all aluminium. It is screwed to the front of the lens
> with 3 tiny screws.
>
> Beware, when you remove the infinity stop you can focus to about 1m,
> nearer than that the front might come off and you'll have difficulty
> putting it back correctly.
Why do you say I'd have difficulty putting it back "correctly"?
What's correctly and incorrectly? You mean it can change
the collimination?
Separate issue. Do you know how to adjust the mirror
holder in case there was astigmatism? And it is possible
to test for astigmatism at daytime by defocusing it?
Thanks.
Win
>
> If you feel adventurous you might like to unscrew the front after all
> and clean the threads of the sticky grease and use some lighter
> grease. The action will be much lighter. I used lithium grease but I
> hear it's not good for optics. There is still no fogging of the optics
> after 4 years.
>
>
>
>
>
> > Thanks.
>
> > Win- Hide quoted text -
Bhogi
> On Mar 26, 12:39 am, Bhogi <bh...@siol.com> wrote:
>
> > > Mine
> > > looks exactly like this:
>
> > >http://www.rugift.com/photocameras/rubinar_1000_lens_for_canon_eos.htm
>
> > Here is mine.http://ejarm.com/rubinarall.jpg
>
> So it is the same as mine. I wonder what you use to
> put diagonal into it? I purchased a separate m42 to
> 1.25" adapter that is only 0.3" length. What adapter
> did you use? Hope you can take a picture without
> the rear cover because I'd like to see the adapter
> you use.
http://ejarm.com/m42to125diagonal.jpg
I made it from black delrin plastic. Your adapter is thinner I think,
I left 10mm of space to use the m6 screws. I use the inexpensive 1.25"
diagonal from surplusshed. I shortened the tube on the diagonal as
much as possible, because I wanted to use the lens with the field
flattener lens, otherwise I'm not sure I could focus to infinity. The
1000 rubinar is ok with all my eyepieces (surplusshed), but the 500 f/
5.6 can't focus to infinity with one eyepiece.
> > > I can't remove the rubber grip because it's stuck between
> > > the body. See again picture at:
>
> > You must remove the grip to unscrew the tiny screws. It's thin and
> > comes off easily you just have to lift it a bit somehow. Putting it
> > back on is also easy.
>
> How many mm distance from the nearest boundary are the screws
> located? If I can't lift all of them up. I'd just cut a portion of it.
I'm not sure about that, but once you can remove the focusing collar
there's enough space to unscrew and remove the stop which is just a
small piece of a aluminium. The main obstacle you're facing is the
large bearing with the tripod thread. It has to go off, because you
can't slide the collar to the front of the lens, it's just a bit too
wide.
> > Beware, when you remove the infinity stop you can focus to about 1m,
> > nearer than that the front might come off and you'll have difficulty
> > putting it back correctly.
>
> Why do you say I'd have difficulty putting it back "correctly"?
> What's correctly and incorrectly? You mean it can change
> the collimination?
because the lens' helicoid has 4, maybe 6 threads. If you don't mate
the correct threads the whole front will be turned differently. I'm
not sure this presents any problems, I'm just telling you.
> Separate issue. Do you know how to adjust the mirror
> holder in case there was astigmatism? And it is possible
> to test for astigmatism at daytime by defocusing it?
The mirror holder can't be adjusted it has the mirror glued on it with
some silicone and it's simply screwed on. From the testing the lens
seems to be diffraction limited as is. My observations of diffraction
patterns confirm it's very good and doesn't need adjustments.
At daytime I just focused realy close on some specular highlights to
get pinpoints of light.
One thing you can do is to unscrew the mirror holder a bit to release
any tension from the mirror. To do this you have to remove a tiny
locking screw from the side of behind part and unscrew it completely
off together with the baffle. You'll need a spanner wrench to unscrew
the mirror holder if it's screwed on too tightly.
> Thanks.
>
> Win
Winstone
> On 25 mar., 21:00, Winstone <winstonewar...@yahoo.com> wrote:
>
> > On Mar 26, 12:39 am, Bhogi <bh...@siol.com> wrote:
>
> > > > Mine
> > > > looks exactly like this:
>
> > > >http://www.rugift.com/photocameras/rubinar_1000_lens_for_canon_eos.htm
>
> > > Here is mine.http://ejarm.com/rubinarall.jpg
>
> > So it is the same as mine. I wonder what you use to
> > put diagonal into it? I purchased a separate m42 to
> > 1.25" adapter that is only 0.3" length. What adapter
> > did you use? Hope you can take a picture without
> > the rear cover because I'd like to see the adapter
> > you use.
>
> http://ejarm.com/m42to125diagonal.jpg
> I made it from black delrin plastic. Your adapter is thinner I think,
> I left 10mm of space to use the m6 screws. I use the inexpensive 1.25"
> diagonal from surplusshed. I shortened the tube on the diagonal as
> much as possible, because I wanted to use the lens with the field
> flattener lens, otherwise I'm not sure I could focus to infinity. The
> 1000 rubinar is ok with all my eyepieces (surplusshed), but the 500 f/
> 5.6 can't focus to infinity with one eyepiece.
What 500 f/5.6 are you talking about? I got my m42-1.25" adapter
ready made from Italy for 20 Euro. See picture at
http://cgi.ebay.it/ws/eBayISAPI.dll?ViewItem&item=140280316066&ssPageName=ADME:X:AAQ:IT:1123
I also ordered a lumicon 1" eyepiece extension (not yet received)
so that I can put any diagonal and it won't hit the rear field
flattener. Why did you cut your diagonal. You can just secure
the front 10mm of any diagonal without getting it all the way
inside that can hit the field flattener. Unless you want shorter
diagonal to avoid aberrations? Why have you compared
using normal diagonal and shortened diagonal? Is the
aberration of the normal diagonal significant? What other
issues or pro/con between using each of them?
>
> > > > I can't remove the rubber grip because it's stuck between
> > > > the body. See again picture at:
>
> > > You must remove the grip to unscrew the tiny screws. It's thin and
> > > comes off easily you just have to lift it a bit somehow. Putting it
> > > back on is also easy.
>
> > How many mm distance from the nearest boundary are the screws
> > located? If I can't lift all of them up. I'd just cut a portion of it.
>
> I'm not sure about that, but once you can remove the focusing collar
> there's enough space to unscrew and remove the stop which is just a
> small piece of a aluminium. The main obstacle you're facing is the
> large bearing with the tripod thread. It has to go off, because you
> can't slide the collar to the front of the lens, it's just a bit too
> wide.
What I mean to say is. If I can't lift up the rubber grip (or
risk damaging the entire rubber grip). I'd just cut a hole
in the middle of it to access the 3 screws. What you
were saying was that once I lift up or cut the rubber
grip I can see 3 screws?
>
> > > Beware, when you remove the infinity stop you can focus to about 1m,
> > > nearer than that the front might come off and you'll have difficulty
> > > putting it back correctly.
>
> > Why do you say I'd have difficulty putting it back "correctly"?
> > What's correctly and incorrectly? You mean it can change
> > the collimination?
>
> because the lens' helicoid has 4, maybe 6 threads. If you don't mate
> the correct threads the whole front will be turned differently. I'm
> not sure this presents any problems, I'm just telling you.
>
> > Separate issue. Do you know how to adjust the mirror
> > holder in case there was astigmatism? And it is possible
> > to test for astigmatism at daytime by defocusing it?
>
> The mirror holder can't be adjusted it has the mirror glued on it with
> some silicone and it's simply screwed on. From the testing the lens
> seems to be diffraction limited as is. My observations of diffraction
> patterns confirm it's very good and doesn't need adjustments.
> At daytime I just focused realy close on some specular highlights to
> get pinpoints of light.
>
> One thing you can do is to unscrew the mirror holder a bit to release
> any tension from the mirror. To do this you have to remove a tiny
> locking screw from the side of behind part and unscrew it completely
> off together with the baffle. You'll need a spanner wrench to unscrew
> the mirror holder if it's screwed on too tightly.
Oh. It was because I remembed something in cloudynights review
of the Rubinar which mentioned about astigmatism. It said
specifically:
"It is relatively easy to loosen the retaining ring which holds
the outermost full aperture lens to the scope (without
dissassembling the entire scope). By doing this, one can
then rotate the outermost full aperture lens relative to
the inner most full aperture lens. In the case of my scope
this has allowed me to "worsen" or "improve" the amount
of astigmatism in the system."
Do you know what he meant by "outermost full aperture
lens related to the inner most full aperture lens"? What
outermost and what innermost?
Thanks.
Win
Bhogi
> On Mar 26, 5:40 am, Bhogi <bh...@siol.com> wrote:
> >http://ejarm.com/m42to125diagonal.jpg
> > I made it from black delrin plastic. Your adapter is thinner I think,
> > I left 10mm of space to use the m6 screws. I use the inexpensive 1.25"
> > diagonal from surplusshed. I shortened the tube on the diagonal as
> > much as possible, because I wanted to use the lens with the field
> > flattener lens, otherwise I'm not sure I could focus to infinity. The
> > 1000 rubinar is ok with all my eyepieces (surplusshed), but the 500 f/
> > 5.6 can't focus to infinity with one eyepiece.
>
> What 500 f/5.6 are you talking about?
http://www.rugift.com/photocameras/rubinar_500_lens.htm
> I also ordered a lumicon 1" eyepiece extension (not yet received)
> so that I can put any diagonal and it won't hit the rear field
> flattener. Why did you cut your diagonal. You can just secure
> the front 10mm of any diagonal without getting it all the way
> inside that can hit the field flattener. Unless you want shorter
> diagonal to avoid aberrations? Why have you compared
> using normal diagonal and shortened diagonal? Is the
> aberration of the normal diagonal significant? What other
> issues or pro/con between using each of them?
You obviously haven't tested the lens with the diagonal yet. The lens
is designed for use with cameras that have 44mm flange distance.
That's not enough distance to mount any 1.25" diagonal. Without the
infinity stop you can focus past the infinity - increase the "flange
distance" - but not by very much. That's one reason to keep the
diagonal as close as possible.
The other reason is, the lens is designed for 44mm distance. To focus
past this designed distance you move the secondary and full aprture
lenses towards the primary mirror which is not what the lens was
opticaly designed for.
Like I said my 500mm rubinar can't focus to infinity with all
eyepieces but 1000 fortunately can do it. But if the diagonal was 5mm
further, I'm not so sure...
>
>
>
> > > > > I can't remove the rubber grip because it's stuck between
> > > > > the body. See again picture at:
>
> > > > You must remove the grip to unscrew the tiny screws. It's thin and
> > > > comes off easily you just have to lift it a bit somehow. Putting it
> > > > back on is also easy.
>
> > > How many mm distance from the nearest boundary are the screws
> > > located? If I can't lift all of them up. I'd just cut a portion of it.
>
> > I'm not sure about that, but once you can remove the focusing collar
> > there's enough space to unscrew and remove the stop which is just a
> > small piece of a aluminium. The main obstacle you're facing is the
> > large bearing with the tripod thread. It has to go off, because you
> > can't slide the collar to the front of the lens, it's just a bit too
> > wide.
>
> What I mean to say is. If I can't lift up the rubber grip (or
> risk damaging the entire rubber grip). I'd just cut a hole
> in the middle of it to access the 3 screws. What you
> were saying was that once I lift up or cut the rubber
> grip I can see 3 screws?
I don't see why you coouldn't do it. Just wedge a small screwdriver
under the grip, lift it gently all around and pull/slide it off. It's
not glued, it's not stiff and it's not very tight. No problem at all.
Just don't cut it.
Under the grip you'll see the screws yes. After you unscrew them slide
the loosened collar to the mount side and below you'll see the
infinity stop.
Here's how the rubinar looks:
http://ejarm.com/rubinar.jpg
It has 2 full aperture lenses in the front. These are the correctors
for the primary mirror. The secondary mirror is a mangin mirror and is
screwed to the meniscus "outer most" lens.
You can also loosen the front retaining ring just to get rid of any
unwanted tension in these large lenses.
> Thanks.
>
> Win
Winstone
For optimum quality. Why don't you use a diagonal that has the
same 44mm flange distance. Not possible? The reason I'm
using a 1" eyepiece extension is because I'm using a Televue
Everbright diagonal and i can't just cut the tube to focus it
closer. With your inexpensive surplusshed diagonal that
you can cut shorter. What is the estimated equivalent
flange distance closest you can get? If close to 44mm.
Then it means I don't even have to adjust the infinity stop
(except perhaps if I want closer focus)?
Also to focus at closer like 1 meter and beyond infinity,
the adjustment of the screws of the aluminum ring is
the same, right. Or is there a separate adjustment if
one wants to focus closer and beyond infinity?
Win
> > Win- Hide quoted text -
>
> - Show quoted text -- Hide quoted text -
>
> - Show quoted text -- Hide quoted text -
Bhogi
A 1.25" diagonal needs some space + the eyepiece needs somespace, I'd
guess all in all a minimum of 60mm. Now if you have a long diagonal
tube this increases.
I think your diagonal tube is not very long so I think you won't have
any problems.
> With your inexpensive surplusshed diagonal that
> you can cut shorter. What is the estimated equivalent
> flange distance closest you can get? If close to 44mm.
> Then it means I don't even have to adjust the infinity stop
> (except perhaps if I want closer focus)?
My guess about 60mm, maybe more. You definitely need to remove the
infinity stop.
Why don't you just try it with the unmodified lens? Just be careful
not to touch the field flattener.
> Also to focus at closer like 1 meter and beyond infinity,
> the adjustment of the screws of the aluminum ring is
> the same, right. Or is there a separate adjustment if
> one wants to focus closer and beyond infinity?
The adjustments you are talking about are just about the distance
scale, how the focusing collar is oriented. With the changed flange
distance I don't think the distance scale is acurate enough. I actualy
never use the distance scale.
All the lens does is move the front group of lenses relative to the
primary mirror. Other than that there is no optical adjustment
possible.
Bhogi
A 1.25" diagonal needs some space + the eyepiece needs somespace, I'd
guess all in all a minimum of 60mm. Now if you have a long diagonal
tube this increases.
I think your diagonal tube is not very long so I think you won't have
any problems.
> With your inexpensive surplusshed diagonal that
> you can cut shorter. What is the estimated equivalent
> flange distance closest you can get? If close to 44mm.
> Then it means I don't even have to adjust the infinity stop
> (except perhaps if I want closer focus)?
My guess about 60mm, maybe more. You definitely need to remove the
infinity stop.
Why don't you just try it with the unmodified lens? Just be careful
not to touch the field flattener.
> Also to focus at closer like 1 meter and beyond infinity,
> the adjustment of the screws of the aluminum ring is
> the same, right. Or is there a separate adjustment if
> one wants to focus closer and beyond infinity?
The adjustments you are talking about are just about the distance
scale, how the focusing collar is oriented. With the changed flange
distance I don't think the distance scale is acurate enough. I actualy
never use the distance scale.
All the lens does is move the front group of lenses relative to the
primary mirror. Other than that there is no optical adjustment
possible.
Winstone
But there is a big difference. I mean normally one can't
adjust the front all the way to focus at 1 meter and less until
the front lens cell comes off. So is there something inside the
aluminum tube that stops it. So you mean by simply loosening
the 3 screws, the front cell itself can be unscrew all the way
from the second half or rear part? Also the two front lens are
contained in one cell?)?
This is last detail I need to know before I start disassembling
it and in the point of no return.
Win
Bhogi
Infinity stop is a piece of aluminium that stops the front cell from
turning the whole 360 degrees in both directions. When you open the
lens you'll see how trivial that is. You don't just loosen the screws
you have to remove the stop.
How much you can focus beyond infinity (increase flange distance)
depends on how far the cell can be moved towards the primary, and near
focus depends on when you totaly unscrew the front cell. You can't
accidentaly unscrew the front cell, it takes a few full 360 degree
turns to do that.
The front cell is one piece yes, exactly like in this drawing:
http://ejarm.com/rubinar.jpg
Follow my directions from the first post, take pictures, and let us
know.
Winstone
Hi, my rubinar finally went into the surgical table. I
was able to remove the mounting ring, removed the
3 screws underneath the collar and moved the collar
to where the mounting ring is (as well as removed
the screws of the aluminum stop). But I can't remove
the collar from the rear. I need to remove the collar
so I can remove the aluminum stop to be able
to focus at a meter or so. Any clue why I can't
remove the collar? There seems to be something
stopping it. Also what bearing are you referring
to in:
"The main obstacle you're facing is the large
bearing with the tripod thread. It has to go off, because
you can't slide the collar to the front of the lens, it's
just a bit too wide."
Is the bearing you mention the mounting ring itself??
I saw no bearing after removing the shoe and
the mounting ring from the main body. There is
no blockage yet I can't remove the collar (need
to because I need to remove the infinity stop).
Any clue? Thanks a lot.
Win
>
> Before putting the ring back on:
> - lock the inner ring of the mounting ring so one hole for the
> screw aligns with the hole, where the "shoe" comes
> - put the ring back on the lens, so this hole aligns with one of
> the holes on the oposite side of the lens where the focusing line is
> (if you don't do this, the focusing line will never lock on top of
> the lens - 4 locking positions and 3 screws)
>
> Hope it helps.
> It realy isn't all that complicated when you have the lens before you.- Hide quoted text -
Bhogi
Ok, you're almost there. Yes the collar/ring/bearing. When you remove
the shoe then thru the hole where the shoe was you unscrew 3 more
screws around the perimeter of the ring. It's a bit tricky but doable
take care that the screws don't fall inside the collar.
The ring is the bearing, thankfuly the balls are hidden safely inside.
It goes off in one piece.
Mark somehow all the orientations so you can quickly put the lens back
together.
Bhogi
Sorry you did all that already.
If I remember correctly I also had the same problems. I think it's
just a little tight but you can take the collar off.
Winstone
>
> - Show quoted text -- Hide quoted text -
>
> - Show quoted text -
What I did instead was unscrew the front cell from
the back until the two half gets separated and then
removed the aluminum ring without having to take
the collar out from the back. It was done. Thanks.
Now for first light. Since it's raining, didn't use it
outside. I tried to focus at an object a meter or
more away. The image is not sharp maybe
because of the magnification. I used a
Televue Diagonal with a Televue 15mm Plossl.
What eyepiece do you use when seeing something
at 1 meter? Maybe the reason the image not clear
is because I didn't cut the male end of the TV
diagonal? TV maile part is one inch unlike your diagonal
which is a mere 1/6". If you can remember,
do the image get worse if you use a normal
diagonal against your cut up diagonal? Is it
that big a difference? I need to know this
because depending on your answer I may
get another diagonal and cut it too if the
difference is that significant. You can easily
compare it by using a normal diagonal with
at least 1" male end versus your cut up
modified diagonal.
I then used the Astro Rubinar oculars included
in the set I bought composing of a straight
thru and prism diagonal. See:
The image is sharp using the same 15mm TV
plossl eyepiece. Looking at their diagonals
with adjustable zoom. There is a lens right at
the 44mm flange distance. You think it's a barlow?
But the weird part is that using their 30mm
eyepiece, magnification starts from 22 to 44.
With the focal length of the scope around say
1,000. Mag is 1,000/30= 33X. So how can they
manage to make a barlow with even lower
magnification than the original. Unless it's
a focal reducer? Or a combination of barlow
and focal reducer? I got a somewhat sleepless
night figuring it out. What lens can you put in
the 44mm flange that can remove the distortions
and at the same time produce even less
magnification.. minimum of 22X and maximum
of 44X (it's a zoom) versus the 33X of the
TV diagonal setup? Any idea? Please see the
above URL for pictures of their straight thru
and right angle prism especially made for
the Rubinar which I also got. Right now the
whole set only cost $560. Cool.
Thanks a lot.
Win
Bhogi
http://www.rugift.com/photocameras/tourist-fl-eyepiece-attachment.htm
It's strange you don't get clear image. I got nice diffraction rings
even with 2x teleconverter. This may be the reason, contrast might be
realy low at close distances.
You won't use the scope this way I guess, don't worry about this too
much.
> Maybe the reason the image not clear
> is because I didn't cut the male end of the TV
> diagonal? TV maile part is one inch unlike your diagonal
> which is a mere 1/6". If you can remember,
> do the image get worse if you use a normal
> diagonal against your cut up diagonal? Is it
> that big a difference? I need to know this
> because depending on your answer I may
> get another diagonal and cut it too if the
> difference is that significant. You can easily
> compare it by using a normal diagonal with
> at least 1" male end versus your cut up
> modified diagonal.
Sorry I only have one diagonal.
I could simulate what you're saying with extension rings, but not now,
it's late. Wait for tomorrow.
> I then used the Astro Rubinar oculars included
> in the set I bought composing of a straight
> thru and prism diagonal. See:
>
> http://lzos.ru/en/index.php?page=shop.product_details&flypage=shop.fl...
>
> The image is sharp using the same 15mm TV
> plossl eyepiece. Looking at their diagonals
> with adjustable zoom. There is a lens right at
> the 44mm flange distance. You think it's a barlow?
I believe it's a relay lens, projecting the image further to the
eyepiece
> But the weird part is that using their 30mm
> eyepiece, magnification starts from 22 to 44.
> With the focal length of the scope around say
> 1,000. Mag is 1,000/30= 33X. So how can they
> manage to make a barlow with even lower
> magnification than the original. Unless it's
> a focal reducer? Or a combination of barlow
> and focal reducer? I got a somewhat sleepless
> night figuring it out. What lens can you put in
> the 44mm flange that can remove the distortions
> and at the same time produce even less
> magnification.. minimum of 22X and maximum
> of 44X (it's a zoom) versus the 33X of the
> TV diagonal setup? Any idea? Please see the
> above URL for pictures of their straight thru
> and right angle prism especially made for
> the Rubinar which I also got. Right now the
> whole set only cost $560. Cool.
If it's a "relay" diagonal you can't just calculate magnification the
normal way. Maybe it introduces some additional magnification.
> Thanks a lot.
>
> Win
Winstone
You mean you can get nice diffraction rings even with
2X teleconverter at a target distance of 1 meter? what
tiny source of light can do that? What I meant to say was.
My image is not sharp at 1 meter target but using other
objects at infinity or several meters away, it is very sharp.
No. It reduces the magnification to half. With a 30mm eyepiece,
I can do 50X using a televue diagonal (I assume the focal
length of the scope becomes 1500/30=50X. But with the
included straight thru, i get only 22X. Somehow the relay
can reduce the magnfication from 50X for a normal
diagonal to just 22X. Know what optical path is involved?
Can't figure this out.
Win
>
>
>
> > Thanks a lot.
>
> > Win- Hide quoted text -
Bhogi
> On Mar 27, 7:47 am, Bhogi <bh...@siol.com> wrote:
> >http://www.rugift.com/photocameras/tourist-fl-eyepiece-attachment.htm
> > It's strange you don't get clear image. I got nice diffraction rings
> > even with 2x teleconverter. This may be the reason, contrast might be
> > realy low at close distances.
>
> You mean you can get nice diffraction rings even with
> 2X teleconverter at a target distance of 1 meter? what
> tiny source of light can do that? What I meant to say was.
> My image is not sharp at 1 meter target but using other
> objects at infinity or several meters away, it is very sharp.
Well then, you made it! Happy clear nights.
I have a lamp with "matte" aluminium reflector that gives nice
pinpoints of light when the light is on.
> > If it's a "relay" diagonal you can't just calculate magnification the
> > normal way. Maybe it introduces some additional magnification.
>
> No. It reduces the magnification to half. With a 30mm eyepiece,
> I can do 50X using a televue diagonal (I assume the focal
> length of the scope becomes 1500/30=50X. But with the
> included straight thru, i get only 22X. Somehow the relay
> can reduce the magnfication from 50X for a normal
> diagonal to just 22X. Know what optical path is involved?
> Can't figure this out.
Like I said, IF it has a relay lens, it projects reduced image from
the 44mm flange distance to the eyepiece. I guess it also inverts the
image for normal viewing.
> Win
Bhogi
> On Mar 27, 4:04 pm, Bhogi <bh...@siol.com> wrote:
>
> > On 27 mar., 01:29, Winstone <winstonewar...@yahoo.com> wrote:
>
> > > On Mar 27, 7:47 am, Bhogi <bh...@siol.com> wrote:
> > > >http://www.rugift.com/photocameras/tourist-fl-eyepiece-attachment.htm
> > > > It's strange you don't get clear image. I got nice diffraction rings
> > > > even with 2x teleconverter. This may be the reason, contrast might be
> > > > realy low at close distances.
>
> > > You mean you can get nice diffraction rings even with
> > > 2X teleconverter at a target distance of 1 meter? what
> > > tiny source of light can do that? What I meant to say was.
> > > My image is not sharp at 1 meter target but using other
> > > objects at infinity or several meters away, it is very sharp.
>
> > Well then, you made it! Happy clear nights.
> > I have a lamp with "matte" aluminium reflector that gives nice
> > pinpoints of light when the light is on.
>
> to remove it because there is nowhere in the internet
> that mentions that the shoe and mounting ring has to
> be removed. Maybe you ought to write up a web
> site about it. :)
Happy to help.
Good idea, I might just do that.
> I wonder if you have seen thru an MTO1000. Can
> you compare the images between it and the
> Rubinar?
I can't I only have the rubinar but there are 2 things:
1) rubinar is SAID to be opticaly slightly superior - diffraction
limited
2) mto has fewer lenses which is a good thing, with rubinar I get a
large purple donut shaped flare on photos with VERY bright light
source in the frame.
> > > > If it's a "relay" diagonal you can't just calculate magnification the
> > > > normal way. Maybe it introduces some additional magnification.
>
> > > No. It reduces the magnification to half. With a 30mm eyepiece,
> > > I can do 50X using a televue diagonal (I assume the focal
> > > length of the scope becomes 1500/30=50X. But with the
> > > included straight thru, i get only 22X. Somehow the relay
> > > can reduce the magnfication from 50X for a normal
> > > diagonal to just 22X. Know what optical path is involved?
> > > Can't figure this out.
>
> > Like I said, IF it has a relay lens, it projects reduced image from
> > the 44mm flange distance to the eyepiece. I guess it also inverts the
> > image for normal viewing.
>
> Whatever it is (after reviewing about relay lens, it is
> possible it is that). It is very effective when viewing target one
> meter away. Without it. You have to use 1600/30= 54X
> which can get the target a bit dimmer esp since any
> close focusing introduces spherical aberrations and
> moving the focal point backward also produce more
> aberrations. So viewing target one meter away can
> produce something like 1/2 wavefront error. By getting
> lesser magnification in the relay (actually it is a zoom
> with variable 22X-44X mag), the image is better.
> When you use 22X magnification at closeup
> you can see great contrast
>
> BTW.. with typical 8" SCT. What's the equivalent
> flange distance to the eyepiece? 100mm?? They
> take into account the diagonal when designing
> 8" SCTs?
I don't know but I'm sure with all SCTs you have enough space for any
diagonal and focuser. Rubinar is a camera lens and has just enough
space for the camera.
> Win
Winstone
Did you get a 1/4 wave or diffraction limited certificate when
you purchased your Rubinar? Some got it but I don't. I wonder
why they no longer issue it maybe because of quality changes
in the newer version? What do you think?
Another thing. Which surprised me. I reread the cloudynights
review of the Rubinar. See:
http://www.cloudynights.com/item.php?item_id=643
The author can focus at infinity using 5 eyepieces and an
uncut celetron 90 degree mirror diagonal without modifying
the aluminum infinity stop. He only removed it when he
took out the rear field flattener & found out he couldn't focus
with some eyepieces. With the rear field flattener installed,
he can focus using any eyepieces and diagonal. How about you.
What's the reason why you removed the infiniity stop? Is it
because you want your eyepieces to focus at infinity?
Unfortunately, I wasn't able to view the scope at the stars
prior to taking off the aluminum stop because of cloudy
skies so I don't know if the original unmodified Rubinar
can focus at infinity using a normal diagonal and any
eyepieces (which the cloudynight reviewer above can).
I'm asking this because if it can focus there is no need
to remove the infiniity stop unless you want to focus
close, right?
Win
Bhogi
If I recall corectly I did get it. Why you didn't get it is pure
speculation.
> Another thing. Which surprised me. I reread the cloudynights
> review of the Rubinar. See:
>
> http://www.cloudynights.com/item.php?item_id=643
>
> The author can focus at infinity using 5 eyepieces and an
> uncut celetron 90 degree mirror diagonal without modifying
> the aluminum infinity stop. He only removed it when he
> took out the rear field flattener & found out he couldn't focus
> with some eyepieces. With the rear field flattener installed,
> he can focus using any eyepieces and diagonal. How about you.
> What's the reason why you removed the infiniity stop?
Because I bought it for use with canon EOS camera with built in flash
that need an extension ring to mount the lens. That's beyond infinity
so infinity stop had to go.
> Is it
> because you want your eyepieces to focus at infinity?
That's how we use telescopes, I'm sure you won't use it for ant
watching either.
> Unfortunately, I wasn't able to view the scope at the stars
> prior to taking off the aluminum stop because of cloudy
> skies so I don't know if the original unmodified Rubinar
> can focus at infinity using a normal diagonal and any
> eyepieces (which the cloudynight reviewer above can).
> I'm asking this because if it can focus there is no need
> to remove the infiniity stop unless you want to focus
> close, right?
I was realy surprised at a few articles about rubinar. They made no
sense for my rubinar, but as you discovered, there are obviously two
versions of the lens. For use with my diagonal, I have to focus beyond
the infinity almost to the phisical limits of the lens, where the
front cell hits the mirror cell (not mirror).
So I realy can't imagine, how cloudynight revier could do it with my
lens.
He couldn't.
Winstone
Maybe the quality changed and it's no longer 1/4 wave
or maybe they just want to save paper (trees could
be getting scare in Russia). There is not even a manual in
my Rubinar bag. The manufacturer just file attached the
manual.
>
> > Another thing. Which surprised me. I reread the cloudynights
> > review of the Rubinar. See:
>
> >http://www.cloudynights.com/item.php?item_id=643
>
> > The author can focus at infinity using 5 eyepieces and an
> > uncut celetron 90 degree mirror diagonal without modifying
> > the aluminum infinity stop. He only removed it when he
> > took out the rear field flattener & found out he couldn't focus
> > with some eyepieces. With the rear field flattener installed,
> > he can focus using any eyepieces and diagonal. How about you.
> > What's the reason why you removed the infiniity stop?
>
> Because I bought it for use with canon EOS camera with built in flash
> that need an extension ring to mount the lens. That's beyond infinity
> so infinity stop had to go.
What exactly is your canon EOS model? And where did you
buy the adapter? I had planned to use camera too. Are you
satisifed with the image? They say a NIkon can produce more
colorful images.
>
> > Is it
> > because you want your eyepieces to focus at infinity?
>
> That's how we use telescopes, I'm sure you won't use it for ant
> watching either.
>
> > Unfortunately, I wasn't able to view the scope at the stars
> > prior to taking off the aluminum stop because of cloudy
> > skies so I don't know if the original unmodified Rubinar
> > can focus at infinity using a normal diagonal and any
> > eyepieces (which the cloudynight reviewer above can).
> > I'm asking this because if it can focus there is no need
> > to remove the infiniity stop unless you want to focus
> > close, right?
>
> I was realy surprised at a few articles about rubinar. They made no
> sense for my rubinar, but as you discovered, there are obviously two
> versions of the lens. For use with my diagonal, I have to focus beyond
> the infinity almost to the phisical limits of the lens, where the
> front cell hits the mirror cell (not mirror).
> So I realy can't imagine, how cloudynight revier could do it with my
> lens.
> He couldn't.
Last things I want to know. If you use a full fledge 1.25" TV
Everbright with longer tube (not cut). Would the image
really degrade in quality significantly? Next time you
are free, please test whether it's significant. The reason I
can't test it myself is because my diagonal tube is not
cut or shortened. According to the reviewer above, his
system becomes 1600mm (F/15) with a diagonal with
normal tube. What if the diagonal tube is shortened like yours,
would the focal length becomes like 1200mm (f/12) or so?
I need to know the figure so I can calculate the degradation
in spherical abberration of a full diagonal and shortened
diagonal.
Thanks.
Win