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Celestron 127 MAK SLT focussing issues


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Hello Guys,

             Hope u all doing well ! I am having a weird issue.  So recently bought this Celestron 127 MAK coz my son is sooo interested in this planets stuff. While watching he dropped it by mistake , but I did manage to stop the fall a bit. Now post recovery, I tried to focus on a very away building and managed to capture it once in a proper view. Then I tried to focus it more & something happened , either I did something to focus finder or some other screws, just dont know what. Lost all the view in the eyepiece & it has always been blurry after that.

           Tried everything after that, all permutations, but just cant get the view in the eyepiece back. SO here's the last thing I managed to find. 

If I remove the eyepiece over the diagonal  & look at it from a distance , I can clearly see a tree or building or the wallpaper on my wall properly. As soon as I get close, I cant. Similarly , If I put the eyepiece back and try to look through it,  zooom in or out through the eyepiece as much as required, just see an image blob. I have added the pix below to show you  how it looks when I look directly through the diagonal from a distance versus when I put in an eyepiece.  

  Have removed diagonal, taken it out, put it out to check if can see through it, yup can see the buildings properly from a distance. Then put an eyepiece 25mm, 17mm , 9 mm , anything. image goes blob. its such a beautiful time to watch planets & my son does not want to miss it. Please help out !!!!!

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with eyepiece and diagonal fitted, does the image in eyepiece change at all when turning the focus knob, or does it stay just the same, and if you gently shake the scope does is sound like something is loose ?

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Welcome to the forum.

Did the fall do any visible damage to the scope? Did you have to fix anything? You mention possibly adjusting some screws, what were they?

Anyway, one thing to bear in mind, scopes are designed for distance viewing, they generally won’t focus very close up, to do  so you need the eyepiece further from the diagonal than normal so that may explain your findings?

First things first, have you tried focusing on a distant object (say 1km away) and does this work?

As Jules says, does anything change when you adjust the focus through its whole range? If not the the fall may have damaged the focus mechanism perhaps.

Do let us know how you get on.

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thanks for the revert  guys. Yea nuthin is looose , all intact. Have tried focussing on a far away object as well. The image comes the same way as I have shown in my pix above. The far away buildings come very crisp in the diagonal if I look at it from a distance a little above the eyepiece  (but no eyepiece attached) . As soon as I insert the eyepiece, the blob comes in. Not matter how much i try to focus in or out.

The screws that I kept turning were the ones on diagonal , tube tightener . Nothing on the actual screws that  are on the tube glass or you know requires screwdrivers.  

 

Where do you live ?- Canary Wharf, London

Did the fall do any visible damage to the scope? --- Pretty sure no damage is done, as cant hear anything rattling inside & like I said when I first set it up post fall, I could see the trees clearly for the first and last time on eyepiece . Then I tightened the tube on the tripod arm a bit more, moved screws on diagonal to fix it more ( All by hands, not the screwdrivers screws). Post that tried everything, took tube out from tripod, removed diagonal and looked from tube, everything is clear form a distance. As soon as I plug in eyepiece (tried 3 diff) , every image goes blurrry and bloby.

with eyepiece and diagonal fitted, does the image in eyepiece change at all when turning the focus knob, or does it stay just the same,-- Stays the same

First things first, have you tried focusing on a distant object (say 1km away) and does this work?- Nope, as answered above

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Have you realised that the focuser has a very large range, tens of turns probab!y?

So worth turning it from end to end to see if you can find focus.

Try holding the 25mm eyepiece above the diagonal, if you find the image then chase it down towards the diagonal with the focuser until you can fully insert it.

Might be that if the focuser is definitely not moving the primary mirror , it has become detatched from the primary in the fall.

Michael 

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thanks for the tips.

So, again 

1) If remove the diagonal and everything just look through the tube, I can see the buildings crisp from a distance.

2) If i put back in the diagonal, see the image from a distance. Can see it crisp. No issues.

3) As soon as I put ANY eyepiece on the diagonal, move UP down, come from far, the image is BLUR and blobby.

1st IMAGE shows windows of a building 2 kms away from the diagonal. The second image just shows how it looks from my eyepiece.

If any one in here near to CANARY WHARF., London... I need your expertise!! Will come over with this box.

PLEASE HELP !!!!

 

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Additionally,  this is how my telescope looks.
the manual for 127 SLT MAK says that thing next to diagonal is a focuser. I did try to rotate it, but in reality its just a rubber cover over an immovable round thing with a screw. 

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You need to move the rubber round thing either clockwise or anti-clockwise to achieve focus - try both directions whilst looking through the eyepiece - you may have to rotate it many times.

Edited by dweller25
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OK here is a procedure for you

1. Remove the diagonal from the telescope.

2. Put the 25mm eyepiece into the telescope

3. Point the scope at a very distant building.

4. Whilst looking through the eyepiece try to rotate the rubber focus knob clockwise - keep going until either the view in the eyepiece becomes sharp or the rubber knob will not rotate anymore.

5. If step 4 did not work whilst looking through the eyepiece try to rotate the rubber focus knob anti-clockwise - keep going until either the view in the eyepiece becomes sharp or the rubber knob will not rotate anymore.

6. If this does not work there is something wrong with the focuser or the mirror may be dislodged.

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Thanks Dweller !  Like I did show in the pic above, the knob is actually a rubber cover to that thing inside. I have tried rotating it, then it came in my hand once, I thought maybe I was being stupid this is just a cover !!

But as u can see in the image, it does say turn in clockwise arrow on it. WOnder why!

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5 hours ago, iamsahil said:

I did try to rotate it, but in reality its just a rubber cover over an immovable round thing with a screw.

If the focuser knob won't rotate, you've probably got a bent or otherwise jammed screw inside the tube that moves the primary mirror forwards and back for focusing.  Did the focuser knob ever turn freely before the accident?  There shouldn't be any significant resistance to motion in one of the two directions, assuming it's at one or the other end of its limit of travel.  If the mirror is somewhere in the middle, it should rotate freely in both directions.

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The focuser knob should rotate easily, and there should be no need to take off its end cap. I was going to suggest that the best way to check the focuser mechanism or get the telescope in focus is to point it at a bright object on a dark background (Arcturus or Venus would be ideal). Typically what you will see is a bright circle with a dark hole at the centre (like a doughnut  or CD).  Turn the knob in the direction that makes the doughnut smaller.

If the knob will not turn when held with thumb tip and finger tip, or it won't focus as outlined above, then you need professional help.  If you are not familiar with telescope servicing you will not be able to fix it yourself.  

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1 hour ago, Cosmic Geoff said:

If the knob will not turn when held with thumb tip and finger tip, or it won't focus as outlined above, then you need professional help.  If you are not familiar with telescope servicing you will not be able to fix it yourself.  

I had a loose retaining ring/collar that moves the primary mirror up/down the baffle tube on my ETX105 after a fall and Jupiter looked like the photo below. This guy... link here --->http://sctelescopes.com/contact/ put it right and collimated it within two hours. He is ex-BC&F/Telescope House.

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Edited by Philip R
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22 hours ago, dweller25 said:

OK try the procedure without the rubber cover (which is there to help you get a good grip to move the actual focuser - the round tube with the hole in it)

THANK YOU... THANK YOU.. THANK YOU!!!!!!

Used a SPANNER.. seems that the focusser knob was stuck after the fall. The SPANNER loosened it and NOW I CAN SEE!!!!! 

I CAN SEE!!!!

LET THERE BE LIGHT !!!!

THANK YOU GUYS !!!!!!

 

NOW ANOTHER QUESTION.... I have got 25, 17, 13, 9 MM with 2 x and 5 x BARLOW... I still cant see SATURN properly !!! Am I doing smthin WRONG ?  I can see VENUS & MARS properly.

Jupiter is also not very clear.

Tips to this newbie appreciated!

 

 

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15 hours ago, dweller25 said:

It appears the focus knob took some impact force and it is directly linked to the mirror, so your scope may need collimating to get good images.

Hey. So I spent a lot of time yesterday. From my location i can see the moon VERY clearly. If I use 9mm it looks like I am literally sitting it.

Now when i point to Jupiter or venus the next brightest objects, they just appear like a star. No matter what lenses, 25, 17,13,9,4 mm I use alone or with 2x Barlow, just cant even see the planets as they should look a bit. Just look like stars.

why i know how they should look: I had a Celestron 114 EQ and i have seen Jupiter and moons from its 17 with barlow. I know how they shud look like and the colors.

but with this.. everything looks like a star. 

Even with mars, which is closest and brightest now. Just looks like a star.

Far away buildings, like 5 kms far, i can literally see what’s written on the entrance. Moon is awesome!! But no planets.

 

please help out. Any tips ...

 

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8 minutes ago, iamsahil said:

Hey. So I spent a lot of time yesterday. From my location i can see the moon VERY clearly. If I use 9mm it looks like I am literally sitting it.

Now when i point to Jupiter or venus the next brightest objects, they just appear like a star. No matter what lenses, 25, 17,13,9,4 mm I use alone or with 2x Barlow, just cant even see the planets as they should look a bit. Just look like stars.

why i know how they should look: I had a Celestron 114 EQ and i have seen Jupiter and moons from its 17 with barlow. I know how they shud look like and the colors.

but with this.. everything looks like a star. 

Even with mars, which is closest and brightest now. Just looks like a star.

Far away buildings, like 5 kms far, i can literally see what’s written on the entrance. Moon is awesome!! But no planets.

 

please help out. Any tips ...

 

My guess is that, if the moon is focusing ok, you are just not correctly lined up on the planets still. Is your tinder aligned correctly still? Perhaps it took a knock in the fall, of if the primary has shifted then it will be out of line with the finder. These scopes have narrow fields of view due to their longer focal length so finding objects, even bright ones can be a challenge.

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48 minutes ago, iamsahil said:

Like i said newbie. Sry what is tinder? And how to align it? Any idea wit my model of telescope?

Finder? The red dot finder attached to the side of the main tube. Adjusted by moving the two knobs which move the dot and allow you to align it with what is visible in the scope eyepiece. Do this on on distance object, either a tree or aerial for instance a mile or so away, or perhaps with the moon. 

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On 19/07/2018 at 20:35, Stu said:

Finder? The red dot finder attached to the side of the main tube. Adjusted by moving the two knobs which move the dot and allow you to align it with what is visible in the scope eyepiece. Do this on on distance object, either a tree or aerial for instance a mile or so away, or perhaps with the moon. 

I have done that guys...pls read my brief description above. Far things, moon etc all have been tried. I can see  Moon from al eyepieces, except the planets...which look like a star dot in all the eyepieces .

 

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The moon is much bigger and easier to find. If the major planets look like stars it is because you are looking at stars. The only options are 

  1. You are misidentifying stars and thinking they are planets. 
  2.  Your finder is not properly aligned so when you point it at a planet it is outside of the telescope field of view. 
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26 minutes ago, iamsahil said:

I have done that guys...pls read my brief description above. Far things, moon etc all have been tried. I can see  Moon from al eyepieces, except the planets...which look like a star dot in all the eyepieces .

 

I'm sorry but if you were looking at a planet with a high power eyepiece then it would not look like a star. The only explanation I can think of is that you are not managing to line up exactly on the planet, and are looking at a background star

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