Skywatcher Mak 150 tips

[Sunshine]

Hello, i have recently purchased a Skywatcher 150 Mak Cassegrain, i have no experience with this design, my intent is mainly visual planetary/lunar mostly, i will be swapping between my Lunt and the skywatcher on my grand polaris mount which is beefy and rock solid, should be no problem holding the 150.

i was wondering if i can pic the brains of those who have experience with Mak's, any suggestions on accessories which are a must have? eyepiece specifications which may suit it best since it does offer a narrow FOV? I'm aware that a dew shield is a must.

fire away and tell me what you believe should be partnered with that scope, id love to hear it thanks!!

[Mr niall]

I do 90% of my work with a Vixen NPL 30mm eyepiece which at 50x on my scope is a great all rounder. I don’t use GOTO so anything but planetary is an absolute killer due to the narrow Fov.  If I had more money (any money ha ha) I think I would throw it all on a good quality 60mm finder, I think in the meantime I’ll get a Telrad I’ve been told they’re a lifesaver for Maks!

[Nojus]

Probably is worth to buy a Crayford dual speed focuser for your Mak..people says it's a huge improvement..

By the way,I've own Mak 180,can prove it's a very good scope with high penetrating optic..

[John]

I think really effective dew prevention gear is an essential with all designs with a big chunk of glass right up the front end - they are "dew magnets" !. At the least a dew shield and for "belt and braces", a heated dew strip as well.

Most eyepieces will work fine with the scope.

They are not wide field scopes and the largest true field you can get from them will be a touch less than 1 degree. A 32mm plossl or a 24mm 68 degree wide angle eyepiece will deliver that. many deep sky objects will fit into a 1 degree field though.

You might want to consider a right angled, correct image finder in due course if your scope is fitted with a straight through type.

If bought out from a house, they need 30-40 minutes to cool down before they will give good views at higher powers.

 

 

[spaceman_spiff]

Don't underestimate cool down time. I thought people were just moaning about it at first but then I started using the scope for imaging and it only starts delivering best results after ~1 hour (depending on weather), and that's after it has cooled down in the garage!

On the plus side, once it has cooled and you have nailed the focus, it gives stunning views.

[Stu]

Agreed, cooling is key to getting the best out of these scopes. If possible, keep it in a cool dry shed or garage, or just make sure you put it out a good hour before using it. It can be worth considering a fan that fits in the focuser too, to pull any warm air out of the baffle tube.

Other than that, a dew shield, preferably heated should do the trick. Regarding eyepieces, don't try to fight the narrow field of view, use the scope for its strengths; lunar, planetary, globs, PNs and doubles. Plus anything else which fits the fov!!

Having said that, although many say not to bother with 2" eyepieces, they can be useful and even though the baffle tube will cause some vignetting, your eye is not that sensitive to it so you will just see the larger fov.

[Sunshine]

WOW you guys are amazing, i just posted an hour ago and you guys are weighing in en mass lol  such a good group!

[spaceman_spiff]

Well SGL is hard to beat!

The Skymax 150 is honestly a great scope that is portable, rugged, and powerful. Lots of possible additions as well.

I do agree with @Stu not to try and force wide a FoV out of it. You will just get vignetting. Also if you do add an extra focuser onto the scope that this will increase the distance from the secondary to the eyepiece and increase the power of the scope (reducing the FoV), not by a huge amount but it is noticeable.

Personally, I have chosen not to add a focuser to the scope as I find the stock focuser pretty smooth and easy to achieve a good focus. You should also get a focus mask (such as a Bahtanov mask) for the scope. It is very useful when imaging and I imagine the same is true for visual work.

[RT65CB-SWL]

I allow 30-40minutes cool down time minimum to acclimatise to the ambient temperature outside if has been kept in a warmer environment.

A dew shield is a definite must have. I use unheated ones on my 're-modded' ETX105 & C6. Alternatively you can make your own from a camping or exercise mat and some Velcro tape, (or duct tape if you just stick it and wrap it round the outer diameter).

If you are happy with the standard 'push/pull' focuser rather than purchasing a Crayford focuser then you may want to consider a SCT star diagonal, ie the type that screws directly to the back (photo 1). 

I use my single-speed Crayford focusser too with my ETX (photo 2) but the focus knob and shaft are to close to the threaded locking collar/ring to enable it to fit perfectly, (with the C6 this is not necessary). So until I purchase a spacer or spacers, I use my field flattener/focal reducer. If I want to use a star diagonal with the Crayford focuser with it, then I have to use a 1.25" push-fit. 

<--- photo 1.            <--- photo 2.

 

Both my star diagonal & Crayford focuser include 2" to 1.25" reducers so that I can happily use my 1.25" eyepieces and 'other' 1.25" accessories too.

 

[Dave In Vermont]

I have the SW 150mm Mak - and it's a truly excellent scope. And you already understand it's inherent narrow F.O.V. and such. So I'll spare you this. However:

The Crayford dual-focus 10:1 is not really a 'must' anymore. Skywatcher does listen to customers, who complained about the focuser having the (normal) mirror-slop, and took this up with Synta which makes these telescopes for SW, Celestron, and Orion-USA. So I, too, heard of the mirror-slop and bought a GSO Crayford, but mine was made after Synta changed the main-focuser. As a result - it really wasn't necessary. The focuser worked very well without the mirror-slop problem. So my advice is to try it without and see what you find. You may or may not want to get the Crayford. And installing these is a breeze!

As for a dew-heater, I haven't found need. Dew-sheild - YES. But not so a heater. It really depends on where you are and your characteristic humidity-levels. The UK - soggy! Vermont not so. So as with a Crayford - try it out first and see what you find.

I always was a optical-finder person. So a 8 X 50mm RACI was my choice. The GSO one is my favorite, and the least costly! A win~win.

I'm sure I'm forgetting something.....Bah! This should do (for now). Other than that - I've had mine for a bit over 2 years now. As it was a choice between the 2 other, most favorite, 127mm & 180mm - I went for the much more rare 150mm. Now I'm seeing more and more folk getting these 150's. Seems they've finally gotten the attention I firmly believe they deserve. The only caveat is portablity. People see these "little" telescopes and presume they'd be easy to port place-to-place. NO. These may appear small - but the front corrector it a thick & heavy piece of glass! So these very powerful dynamo's of a telescope are really not a 'grab-and-go' choice. Armed with this knowledge, you're going to LOVE this telescope!

Enjoy!

Dave

[Sunshine]

That's some amazing advice Little Green Man! i can't wait! i also can't wait until i can add the Tak TOA 130 to my collection, couple years down the road but it will happen!

[nightfisher]

Great scope, had 2 of them, when focusing its best to get into a habit of going past the point of focus (out focus) then fine tune back IN this way you are pushing the mirror and using its own weight to stop any mirror flop, dew shield wants to be about 12" long

[Geoff Lister]

A simple dew shield can be made from a piece of dark, dense foam, yoga/camping mat; with a few strips of gaffer tape and stick-on Velcro. Even a simple cardboard tube + tape, will help delay dew formation. Extra focus-knob sensitivity can be obtained by using a clothespeg to increase the lever arm when close to focus.

I have 2 of the 127mm OTAs, in different locations, and, on one, I replaced the straight-through finder with its RACI equivalent; much more user-friendly, particularly for targets at high altitude angles.

Geoff

[Dave In Vermont]

The advice by Jules on back-focus is spot-on. This problem disappears if you've added a Crayford-Focuser and set it up properly.

The Celestron dew-shield, as it advertises 'Celestron' I imagine, is quite inexpensive - less than the plain Astrozap from Astrozap that makes these. At least over here.

Dave

 

 

[Analysis Paralysis]

On 12/11/2017 at 20:51, Sunshine said:

Hello, i have recently purchased a Skywatcher 150 Mak Cassegrain, i have no experience with this design, my intent is mainly visual planetary/lunar mostly, i will be swapping between my Lunt and the skywatcher on my grand polaris mount which is beefy and rock solid, should be no problem holding the 150.

i was wondering if i can pic the brains of those who have experience with Mak's, any suggestions on accessories which are a must have? eyepiece specifications which may suit it best since it does offer a narrow FOV? I'm aware that a dew shield is a must.

fire away and tell me what you believe should be partnered with that scope, id love to hear it thanks!!

Hi sunshine

 

I'm thinking of getting the 180 version, although my enthusiasm was recently dented when it was pointed out that the main planets Jupiter, Saturn are not well placed from northern hemisphere for next few years!?But, double stars and lunar still possible and some bright DSO. I'll be interested to see if you advised to put a ds Crayford on it...

[Analysis Paralysis]

On 13/11/2017 at 03:10, Dave In Vermont said:

I have the SW 150mm Mak - and it's a truly excellent scope. And you already understand it's inherent narrow F.O.V. and such. So I'll spare you this. However:

The Crayford dual-focus 10:1 is not really a 'must' anymore. Skywatcher does listen to customers, who complained about the focuser having the (normal) mirror-slop, and took this up with Synta which makes these telescopes for SW, Celestron, and Orion-USA. So I, too, heard of the mirror-slop and bought a GSO Crayford, but mine was made after Synta changed the main-focuser. As a result - it really wasn't necessary. The focuser worked very well without the mirror-slop problem. So my advice is to try it without and see what you find. You may or may not want to get the Crayford. And installing these is a breeze!

As for a dew-heater, I haven't found need. Dew-sheild - YES. But not so a heater. It really depends on where you are and your characteristic humidity-levels. The UK - soggy! Vermont not so. So as with a Crayford - try it out first and see what you find.

I always was a optical-finder person. So a 8 X 50mm RACI was my choice. The GSO one is my favorite, and the least costly! A win~win.

I'm sure I'm forgetting something.....Bah! This should do (for now). Other than that - I've had mine for a bit over 2 years now. As it was a choice between the 2 other, most favorite, 127mm & 180mm - I went for the much more rare 150mm. Now I'm seeing more and more folk getting these 150's. Seems they've finally gotten the attention I firmly believe they deserve. The only caveat is portablity. People see these "little" telescopes and presume they'd be easy to port place-to-place. NO. These may appear small - but the front corrector it a thick & heavy piece of glass! So these very powerful dynamo's of a telescope are really not a 'grab-and-go' choice. Armed with this knowledge, you're going to LOVE this telescope!

Enjoy!

Dave

Hi Dave

I am planning on getting the 180 mak to compliment my 80ed. I was very interested in your comment about the factory fitted focuser being much better now. So I won't leap into getting the Crayford unless really needed. In the past I heard it wasn't possible to fit one to the Mak. I assume skywatcher listened to people there and changed the design to allow this. But I will be getting a dew shield!

Mark

 

[Analysis Paralysis]

On 15/11/2017 at 10:45, Geoff Lister said:

A simple dew shield can be made from a piece of dark, dense foam, yoga/camping mat; with a few strips of gaffer tape and stick-on Velcro. Even a simple cardboard tube + tape, will help delay dew formation. Extra focus-knob sensitivity can be obtained by using a clothespeg to increase the lever arm when close to focus.

I have 2 of the 127mm OTAs, in different locations, and, on one, I replaced the straight-through finder with its RACI equivalent; much more user-friendly, particularly for targets at high altitude angles.

Geoff

Hi Geoff

Can you post a photo of your clothes peg in action?

 

Cheers, mark

[Bobby1970]

On my 127 I made a "jiffy" focuser. 

See here:-

https://stargazerslounge.com/topic/293214-jiffy-focuser-for-mak/

Definitely helps with fine focus

[Geoff Lister]

21 hours ago, Analysis Paralysis said:

Can you post a photo of your clothes peg in action?

As requested:-

Not the world's best peg for holding my socks on the line, but an easy grip/release action on the focus knob.

Geoff

[Analysis Paralysis]

7 hours ago, Geoff Lister said:

As requested:-

Not the world's best peg for holding my socks on the line, but an easy grip/release action on the focus knob.

Geoff

Thanks Geoff.

Are you able to obtain the fine tuning you require. 

Apparently the latest skywatcher maks will allow a dual speed Crayford, but obviously at a cost.

Mark

[Geoff Lister]

There is still some slack in the adjuster, so it is sometimes necessary to pass the focus point and then reverse the direction of knob travel. The peg just gives a slight edge in landing on the focus sweet-spot (after the mount vibration has finished).

I was aware that Skywatcher produced a dual-speed Crayford assembly as a retro-fit for their refractors. As far as I know, the focus on the Mak. is performed by moving the primary mirror cell, whereas a Crayford focuser moves the eyepiece. It should be possible to also move the eyepiece on a Mak., but I am not sure if the OTA's backplate would take a focus tube. A Mak. is, by its design, a short OTA; so adding a rear focus tube would negate some of that advantage, particularly if observing close to the zenith.

Geoff

 

[Lee_P]

Is there kit available to autofocus this telescope, so it can be automated through SGP?

[Geoff Lister]

I've seen a couple of photos of a remote focus system, using a motor/gearbox assembly bolted on the side of the backplate, and a belt drive engaging with the rubber splines on the focus knob. I think this was connected, by a thin cable, to a small box with a battery and in/out pushbuttons and some form of speed adjuster. This reduces the mount vibration induced by touching the focus knob, but is not automatic.

Geoff

[Lee_P]

3 hours ago, Geoff Lister said:

I've seen a couple of photos of a remote focus system, using a motor/gearbox assembly bolted on the side of the backplate, and a belt drive engaging with the rubber splines on the focus knob. I think this was connected, by a thin cable, to a small box with a battery and in/out pushbuttons and some form of speed adjuster. This reduces the mount vibration induced by touching the focus knob, but is not automatic.

Geoff

Ah, so there's no package that can be conveniently bought from FLO?

[Geoff Lister]

They do this for refractors, https://www.firstlightoptics.com/skywatcher-focusers/skywatcher-auto-focuser.html and with this https://www.firstlightoptics.com/astronomy-cables-leads-accessories/hitecastro-dc-focus-controller.html it could be controlled by a computer.

It could probably be adapted to work on a Mak.