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Questions about my new 8 inch reflector


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Hi,

First post here. I got a Konus Konusky 200 Motor telescope (model 1793 I think) yesterday as a present (a bit of research went into it). This is my first telescope.

There's variations of this model, but this is the one I have http://www.konus.com/prodotti.php?id_c=15&id_p=232

The instruction manual was a generic one and very confusing. I didn't even have a part list. I had to guess my mount was an EQ5 by looking at the pics and they looked slightly different to my setup, but I got there in the end (but not the motor, looks too complicated for now).

So last night I aligned the finderscope and telescope to the first bright star I saw (Capella I think), then found Polaris by eye when it got dark enough, and after a short browse around the sky Saturn came up high enough and... well it blew my socks off!

Anyway, from that you can tell I've worked out some of the basic alignment principles (on the fly!) but I've got a lot of questions about the equipment I have, so apologies in advance for the length of this post and lack of correct terminology, but I've attached pictures to help.

The telescope came with 10mm and 26mm eyepieces. I've no idea if they're different kinds, but 10mm is short and the 26mm is about twice as long. Made by Plossl.

1) What is this thing? (IMG_0620.jpg & IMG_0621.jpg). It's a tube with no lens in, and has thumbscrews. After trying it in various places, I worked out it fits between the eyepiece and the focusing tube attached to the telescope (IMG_0623.jpg). My guess was it somehow extends the focal point? But I tried it with the 10mm and 26mm and I couldn't get a focused image of a star or Saturn.

2) The reflector tube has a cover with two circular bits (IMG_0624.JPG). One has a cap which you can take off, the other is sealed. What are these for? When would you take one off (looking at the moon?) Why is the other bit sealed?

3) Removing the eyepiece, opening the reflector tube cover and looking into the focuser tube, you can see your eye in the middle, and the mirror around it (MirrorViewNoLens.png). Look closely at the picture I took and you'll see my iPhone camera lens in the center and then a black ring around it that is offset. No matter where I move my eye, this ring is always offset. I assume the black ring is either the reflector tube or the focus tube? The top of the black ring (label A) is much larger than the bottom (label :). Does this mean that one of the mirrors is not aligned correctly? i.e. it needs "collimation"? The manual has a section on this, but it looks worryingly complex and needs a 35mm film canister cap! Er... do they exist now?

That's it for now, no doubt I'll have more beginner questions when I get going again properly tonight (no clouds please!)

Thanks in advance for your assistance.

Boz

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Edited by DaBozUK
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number 1............. there are different sizes of eye peices..... 1 1/4 inch and 2 inch... thats for when you gt 2 inch eye peices which give you a larger vewing point

number 2...... i hoping someone tells me tooo as i got a 200mm skywatcher reflector...

number 3........... thast just how reflectors are... once you put lens in... it vanishes....

im a newbie.... and i know someone will explain this alot better lol

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Download this manual it may help TELESCOPE SUPPLIERS - SKY-WATCHER TELESCOPE

You basically have a Sky-watcher Explorer 200p on a variant of a EQ5.

#1) As Raju said.

#2) Usually removed to view the sun WITH SUITABLE SOLAR FILM FITTED!! Baader Planetarium AstroSolar Safety Film

#3) Astro Babys Guide to Collimation Will explain everything you need to know.

SPACEBOY

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Sure looks like a EQ5...

The eyepieces are not made by Plossl. Plossl is an eyepiece type, not a brand. They should work for now.

#1) From what it looks like initially, it could be an focuser extension. On the third pic, it is attached to what it looks like a t-adapter for cameras (see the threads?).

#2) The covers on the dew shield could work to stop some aperture and see very bright objects. Don't know why only one can be uncovered.

#3) For sure, it's not aligned and needs collimation, i.e. mirror alignment. Don't be scared, it's not very difficult. There are many threads and tutorials around to help you do it. If you can get what is called a "Cheshire eyepiece", it will make collimation easier and they are very cheap. More expensive alternatives are collimation lasers.

The scope should work properly once it is collimated.

Edited by gustavo_sanchez
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As ragu says the black tube is an adaptor to turn your 11/4" to a 2" fittment for eyepieces. If you could get a clear view of saturn it's unlikely it needs collimating right now but you will need to know how it's done. the hole in th scope lid is to stop the scope down, some people find looking at the moon too bright, leaving the cap on and just taking the small one off will make the moon less bright ( will also be a less resolved image) the small hole is useful. if you put some solar film on it you can look at the sun. Hope that helps.

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Number two is an off-axis aperture stop, and the other side is a 'storage bump' for you to put the cap when you are using the open side!

You normally reduce aperture like this when you are looking at something very bright, such as Luna. This is NOT a solar filter, and DO NOT attempt to look at the sun without a proper filter made for your scope!

The idea is that you reduce light, and you convert your scope from an 8" f/5 to a 3" f/15 off-axis - very good in poor seeing, but you cut your resolution down, too. I prefer neutral density filters at the eyepiece for lunar viewing!

The focus extension is great for some wide angle eyepieces that won't focus as close as others, the T-ring adapter will allow you to add a bayonette fitting that matches a DSLR camera so you can take astrophotos.

Dan

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Number two is an off-axis aperture stop, and the other side is a 'storage bump' for you to put the cap when you are using the open side!

You normally reduce aperture like this when you are looking at something very bright, such as Luna. This is NOT a solar filter, and DO NOT attempt to look at the sun without a proper filter made for your scope!

Dan

Thanks for that on re reading my post I hadn't made it sufficiently clear. Some people put solar film over that hole which is a special film to look at the sun otherwise DO NOT look at the sun

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Thanks all for the responses, I can't wait to get back home and collimate! Better explain to the wife it's not what it sounds like.

One thing perhaps the pictures didn't make clear is that the first 2 pics are of the mystery extender, and the 3rd pic shows the smaller eyepiece adapter. The mystery extender fits between the eyepiece adapter and appears to be same size apperture, i.e. not a converter. Make sense?

So given that it extends and doesn't adapt... what's it for? Is it a camera adapter? If so, where would I put the eyepieces? Or do you not use an eyepiece when using a camera?

Cheers

Boz

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You can use eyepieces with camera to get small things (planets) up to a decent scale on the camera. For deep sky, which is very complicated, you attach the camera as if the scope were its lens, which it is!

I guess the extender is simply needed to get the camera to come to prime focus, ie without eyepiece.

Olly

ollypenrice's Photos

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Thanks all for the responses, I can't wait to get back home and collimate! Better explain to the wife it's not what it sounds like.

One thing perhaps the pictures didn't make clear is that the first 2 pics are of the mystery extender, and the 3rd pic shows the smaller eyepiece adapter. The mystery extender fits between the eyepiece adapter and appears to be same size apperture, i.e. not a converter. Make sense?

So given that it extends and doesn't adapt... what's it for? Is it a camera adapter? If so, where would I put the eyepieces? Or do you not use an eyepiece when using a camera?

Cheers

Boz

Hi Boz,

think of the extender and the camera like an old-fashioned slide projector and screen (the camera film or CCD is like the screen). When you pull the projector back, the image on the screen gets larger, but dimmer. This means that when photographing something small (like a double star or a planet), the extender can make the image bigger so you can see more detail. The trade off is that you need more exposure time, and that can be tricky if your exposure gets over 30 seconds or so because it requires virtually perfect tracking by both telescope and mount to keep the photo from being smeared out by camera movement.

hope that helps,

Dan

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I prefer neutral density filters at the eyepiece for lunar viewing!

I've got a small dark lens, thin like a coin. Is that one of these?

The focus extension is great for some wide angle eyepieces that won't focus as close as others, the T-ring adapter will allow you to add a bayonette fitting that matches a DSLR camera so you can take astrophotos.

what does the focus extender look like, compared to a T-ring adapter. I'm still not sure what I've got.

Thanks

Boz

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The small dark lens should screw into the bottom of the eyepiece, which then slips into the focuser - yep, that's it!

The focus extender is just that, a hollow tube thinner at one end, wide enough to accomodate a lens (or camera adapter) at the other end. Usually has a set screw to hold the next accessory in, but nothing else.

The 'T-ring' camera adapter is very short, and has a 1.25" barrel (like an eyepiece) on one end, and then the other flares out to about 2-inches wide and has threads on the edge. This piece screws into the bayonette adapter (called a T-ring - you must get one to match your camera like Canon, Nikon, etc).

If you look up "focal extender" and "T-ring Adapter" on any astro shop's website, I bet they'll have a picture to help out. Check with FLO, I bet they have one there.

Hope that helps,

Dan

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Thanks everyone for your help and explanation of the mystery parts I have. I re-read the instructions and quite a bit makes a lot more sense now. My issues seem to be understanding the tech rather than understanding the sky at the moment.

I haven't collimated yet, but did spend a while last night getting the motor attached. Just need a cloud free night now!

Thanks again.

Boz

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