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What should I get for my Skywatcher 200P?


Tundra
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Hi, I'm new here but I have a decent grip on the basics of astronomy.  I currently have a 70mm EQ mount which I've gotten to known pretty well and I now feel comfortable using EQ mounts.

 

I've decided that I want to get a Skywatcher 200P, but there are many options.  Do I want a normal or DS focuser?  Do I need to get a heavier HEQ5 mount?

 

Basically I have 4 questions that I'm hoping you can answer:

        Do I need the DS version?  I haven't started to do any AP yet, but I might be interested in doing it in the future.  Apparently the mirror is closer in the DS, but if that's so why is the focal ratio still the same?

        Do I need to get the heavier but more sturdy HEQ5 that comes with motors and a GOTO pad?

        Do you think I would need a GOTO option instead of just a motor on the equatorial axes?  Is it really that necessary to find dimmer objects?

        If I get a GOTO mount, and this may seem like a very silly question, can I still use it manually?  If I turn it off, can I still track and move the telescope around without damaging the motors or gears?

 

Here's a link to the HEQ5 version:  https://www.firstlightoptics.com/reflectors/skywatcher-explorer-200pds-heq5-pro.html

 

Thanks alot!

Edited by Tundra
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If you have any inclination to use a 200P for imaging then get the DS version.  The larger secondary reduces the risk of artefacts such as additional pikes on stars etc (talking from experience).  The 200P can act like a sail in breezy conditions, so a sturdy mount is needed if the scope is used in exposed conditions.  HEQ5 copes well, especially if you can shelter the set up, EQ6 is a lot more capable.  However if you are looking at a portable rig, weight will need to be a considering factor.

If you opt for an HEQ5 or EQ6 you can only get these with built in motors and a synscan goto unit.

HEQ5 / EQ6 mounts are not designed to be used manually.  By that I am referring to the lack of any flexible manual adjustments to fine tune the positioning.  They both have clutches on both axis which can be released to position the mount and then use the directional buttons on the handset to do the fine tuning.  But why you would want to manually move the scope when an aligned goto system removes the need to.  

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I had a 200P on an HEQ5, and it worked fine. Later, I did upgrade the HEQ5 to an EQ6, but I wouldn't say it was essential. EQ6 mounts do come up on Astro Buy Sell, so I would have a look there.

I would go for a 200PDS if you are contemplating imaging. The 200P is primarily a visual scope, and the focus point is fairly close to the tube, and the secondary mirror is small, which is all that is needed for visual. The close focus point means that a camera, such as a DSLR, with a deep body, might not be able to reach focus. Modern CMOS cameras with the sensor close to the front face of the camera might work on a 200P but the smaller secondary could give significant vignetting.

The 200PDS has a focus point further out from the tube giving space to instal a camera plus filters if needed. The larger secondary mirror gives a wider field of view.

David

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13 hours ago, Tundra said:

Apparently the mirror is closer in the DS, but if that's so why is the focal ratio still the same?!

The secondary mirror sits closer to the primary, which means it is in a wider part of the light path, which is one reason the secondary needs to be bigger. It also means there is a longer part of the light path after the secondary than there is on the 200P, so it projects further out of the side of the tube before coming to a focus. This allows deeper camera body to sensor dimensions and also allows fitting of various accessories in the light path after the secondary. But, because the secondary is closer to the primary, the sum of the two parts of the light path after the primary is still the same.

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10 hours ago, davies07 said:

The 200P is primarily a visual scope, and the focus point is fairly close to the tube, and the secondary mirror is small, which is all that is needed for visual. The close focus point means that a camera, such as a DSLR, with a deep body, might not be able to reach focus.

Thanks for the replies!

Getting the 200PDS would still allow to focus to be reached when using eyepieces, right?   I'm not sure how long the focusing tube is on it.   I would be using anything from a 5 to an 30mm eyepiece for my viewing tastes.

 

As for why I might want to use the mount without a computer...

It might be nice to not have to worry about bringing out battery and electrical equipment out sometimes and, some people might disagree, but I still think that there a certain charm to going out there and looking at the starts with just you and your scope.  No computer, no motors, just your good old fashioned hands.

 

One more thing, do you think that you could recommend a good starting camera to use with this?  

Thanks.

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9 minutes ago, Tundra said:

Thanks for the replies!

Getting the 200PDS would still allow to focus to be reached when using eyepieces, right?   I'm not sure how long the focusing tube is on it.   I would be using anything from a 5 to an 30mm eyepiece for my viewing tastes.

As for why I might want to use the mount without a computer...

It might be nice to not have to worry about bringing out battery and electrical equipment out sometimes and, some people might disagree, but I still think that there a certain charm to going out there and looking at the starts with just you and your scope.  No computer, no motors, just your good old fashioned hands.

One more thing, do you think that you could recommend a good starting camera to use with this?  

Thanks.

Basically you can't have your cake and eat it,  for want of a better phrase.    If you want to a scope that is easily portable so you can drive out to a dark site and just do some basic astronomy without any concerns of power, computers and such then look at getting a 150p (or PDS) / EQ5 combination.  You could consider an 200PDS / EQ5 combo, but as mentioned the 200P can be subject to breezy conditions.  But that would not be the ideal combination for imaging.  It will work, and there is a long running thread on imaging on an EQ3 mount, but IMO gives you one more hoop to jump through.  You could always buy motor drives, either basic or synscan goto for an EQ5 at a later date, but you won't get the additional precision that the HEQ5 or EQ6 provides.  But then as mentioned these mounts by design lack manual use option of the RA/DEC axis as they have the goto system installed as an integral part of the design.

You can still do visual observing with a PDS, but I think you are at that fork in the road and need to decide which path you want to go down.  An HEQ5 that at minimum will need a decent 12v power pack or car battery for the times you just want to look through the scope, but can then readily accept the additional load of guide scopes and cameras, and be controlled from your laptop / pi / dedicated astro PC etc if / when you chose to do imaging.  Or an EQ5 that has the means to manually do the fine tuning,  but can have a driven option fitted at a later stage, but lacks the accuracy and load carrying ability of an HEQ5

It has to be your choice... choose your own destiny ( I don't know why but I could hear Darth Vader saying that last bit !)

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Are you dead set on putting the reflector on an EQ mount?   Manual EQ mount options stop with the EQ5 - which I (personally) wouldn't want to put the weight (and bulk) of an 8" reflector on it.  After that - the HEQ5 etc you have to be using connected up to power and using the GOTO or the controls at least.

Personally, if you haven't bought the 200p yet then I'd just go for an 8" or 10" dob now for visual and if you have any inclination for imaging later on then get an extra setup for the purpose (a small refractor or the 130PDS on a HEQ5/EQ6/AVX or whatever...

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I bought my Explorer 200P  13 years ago and never had a problem reaching focus with my DSLR which has a back-focus from adaptor to sensor of 55mm.  I could still wind the focus in by several centimetres.  I remember there used to be focus problems with a previous generation of 200Ps.  So, my guess is that it shouldn’t be a problem for any recent 200Ps sold by retailers or second hand. But if in doubt, ask!

I used my 200P for visual and imaging on an old EQ5 without guiding or GOTO.  It was fine for visual, but frankly for imaging it was considerably under specced.  It is quite good fun using a mount without GOTO. You learn the sky! But frankly it’s as frustrating as hell to find small and faint objects.  With GOTO it’s a joy.

Knowing what I know now I’d go for the most capable mount I could afford and which I was comfortable carrying around and setting up.  More capable usually means heavier.  A scope that sits in a spare bedroom because it’s just too much of hassle to carry outside is just taking up space.

Just thinking outside the box for a moment ……. why not look at smaller scopes on a harmonic drive mount like that sold by ZWO?  I think if I was in your position, @Tundra I might look very seriously at such a mount.  

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