SkyWatcher Pro 180mm (7 inch) Mak Cas
Submitted: Thursday, 22nd March 2007 by Mike (aerobrake)
This is a quick review and thoughts on a SkyWatcher Pro 180mm (7 inch) mak cas telescope that I have just acquired in Sydney. The scope itself is very solidly built but lacks finesse in the finish if you look closely, however this does not have any affect on the views thru the scope. The finder-scope seems to be of reasonable quality and certainly does the job of helping you zero in on your target. The front meniscus corrector had a slight tinge of the optical coating on it which looked perfect with no difference in shade or colour anywhere on the corrector. There was a couple of biggish bits of dust on the mirror when I picked up the scope from the shop but managed to shake them off the mirror, other than that the inside of the scope looked clean with a matt finish.
The rubber focus knob is very smooth to turn and is one of the best “feeling” ones I’ve used. There is about a “2 jupiter” diameter mirror shift using a 12mm eyepiece when changing from inside to outside focus. I connected up my ToUcam 740 webcam for some planetary photography and at no time did the plane leave the viewing area when I changed focus directions. There is some shaking when adjusting focus but I did not find it to be any more or less than my Lx90 etc and certainly not bad. I was a bit worried about it initially as there are only 2 bolts that hold the dovetail onto the OTA. I have connected a Losmandy universal plate to the dovetail that is attached to the OTA (see the piccies). I would not be piggybacking anything on top of the scope unless you can find and use tube rings to attach the OTA to a mount as I dont think the “ factory dovetail to OTA” connection is very robust. Having said that there is no worries using the scope “as is”.
Now for the important bit. The views thru the scope are very good. My example turned up almost perfectly collimated optics (there are 3 collimation bolts on the mirror at the back of the OTA for your adjustment). I used a Denkmeier binoviewer with 12mm University Optics ep’s for some of the best views of Saturn I’ve seen. I let the scope cool outside for about an hour and a half. Focus was easy to find with very good contrast images. I then turned to Luna and was again rewarded with fantastic views with sharp contrast. I did, however, notice a green ghosting of what looked like the reflection of the meniscus and the secondary spot if I pointed the OTA away from the moon with the moon just on the edge of the field of view. This requires further investigation as it might have been something in the ep’s or binoviewer combination but I have not noticed this in any of my other scopes using the same equipment. When looking directly at the moon there was no ghosting evident.
Speaking of the secondary spot on the meniscus, it is 44mm in diameter but there is a further obstruction of about 8-10mm as there is a conical glare shield surrounding the secondary spot (see pic) so I would estimate the obstruction to be about 54mm. This represents an obstruction of 30% by diameter, not small but not huge either.
In conclusion this is a good scope and a keeper. It is built a little like a workhorse and does lack a little finesse but this does not have any affect on the views thru the scope which are very good. If you have the means and desire to own the SkyWatcher mak, go for it!!!!