New Skymax 150 mm.

[Guest]

I have just acquired a new Skymax 150mm. Just wondering how other owners have upgraded or improved the focussing system. Perhaps a Baader clicklock (is there one available)?

Or a better focussed? I would be interested to hear. Any pictures of your upgrade would be great.

Thanks.

Martin.

[nightfisher]

There was a revelation focusser  for this scope, i think any crayford for SCT should fit and regarding dew shield why not make one, stick with the 150 mak, they are a good scope, i have owned 2 of them

[nfotis]

If this has the SCT visual back, you just attach a 2" dual speed focuser, like the TS Crayford focuser.

You do the rough focus with the standard focuser, and fine tuning with the dual speed one.

https://www.teleskop-express.de/shop/product_info.php/language/en/info/p781_TS-Optics-2--Dual-Speed-Crayford-Focuser-with-SC-thread-connection.html

N.F.

 

[Captain Scarlet]

I have 2 Skymaxs, a 150 and a 180. As all above have suggested, you can obviously focus using the "native knob", which actually works fine, or you can add a Crayford focuser to the back. I do have Crayfords for my Skymaxs, but increasingly I simply use the knob. The problem with the knob is that it rotates a nut around a threaded bar the other end of which is attached to a bulkhead-and-sledge to which is bonded the primary mirror, which slides up and down the central baffle tube. To allow this movement, the outer baffle tube (to which the primary mirror is bonded) sits around the inner tube, and there is necessarily clearance and lubrication. Turning the focus-knob causes the outer tube to very slightly tilt with respect to the inner, causing the mirror to very slightly change orientation. At high magnification, this results in "image shift" as you focus.

The Crayford avoids this problem, but it has 2 drawbacks (no pun intended). It makes the scope very back-heavy, and it significantly increases the focal length, of the order of 200mm in my Skymax 180, probably slightly less in the 150.

Another upgrade, which I have done, is to buy the Feathertouch FTM-CPC8 upgrade to the native knob. It's very good, but expensive.

Finally another tip: I was finding my Skymax focus knob to be very "stictiony". I solved this problem by realising that the rubber knob is actually just pushed on to a big steel cylinder, and the rubber was in direct contact with the back end of the scope, and would stick to it. Just pull the knob out 0.5mm or so to avoid the rubber contact and you'll find it to be very smooth.

I hope helpful, Cheers, Magnus

[Splodger]

If you on a really tight budget and just want finer control try The Poor Man’s Dual Speed Focuser - A Clothes Peg! Seriously, it works a treat. Just clip it onto the knob at 90° et voila! Fine adjustment at your fingertips. It works for me 😃

[GazOC]

5 hours ago, Splodger said:

If you on a really tight budget and just want finer control try The Poor Man’s Dual Speed Focuser - A Clothes Peg! Seriously, it works a treat. Just clip it onto the knob at 90° et voila! Fine adjustment at your fingertips. It works for me 😃

So it's not just me who does this! I've mentioned it a few times in threads over the years but no-one ever seems to follow up on it 🤣

[badhex]

14 hours ago, GazOC said:

So it's not just me who does this! I've mentioned it a few times in threads over the years but no-one ever seems to follow up on it

Clothes peg user here too, on my old Skymax 102! 🙋