Telescope Reviews: That extra inch…

Last night my son and I were out at a dark site in frigid weather. The temperature dropped from -10C (14F) to -20C (-5F) during our 2 hour session, but we were dressed appropriately (and the cottage was not far away

). We took both the 127Mak and the 150 F5 Newt with us on this moonless night of average seeing, figuring that we had both planetary and DSO well covered. We looked at favourites such as M42, the double cluster, open clusters in Auriga, but what surprised me the most was Jupiter. I knew that aperture made a difference, but I did not expect to be as noticeable as it was with just an extra inch. Also, I have always believed that an F5 Newtonian would not be as good on planets because of how sensitive it is to collimation (I used a Cheshire to check it before we went out). I was wrong.

Jupiter was amazing in the Newt. It was noticeably brighter and the edge of the bands were sharper and more defined on average than in the Mak. The Mak was still very good but the sharpness came and went while it was steadier in the Newt. Both scope had cooled for two hours, but perhaps the Mak was still sensitive to the dropping temperature or to body heat (and breathing). The Mak on the other hand was a touch better on contrast. Polar shading was more obvious, but a bit being the key word. I believe that the extra brightness of the Newt was a strong advantage and it helped seeing some detail in the bands, while in the Mak I had to tease them out by patiently sitting and observing.

The Newt also offered nice low power wide field views but the Mak still offered amazing views of M42 and the open clusters; it just was not wide field but that was not a bother. In the end, both of these are very nice scopes at a dark site and each has its advantages. The real advantage of the Mak is ergonomics. It was more comfortable being seated behind it when we wanted to look at an object for an extended period of time. This made it easy to wait for periods of clear seeing, during which very nice detail came into view. The Mak is also easier to take with us while the Newt stays at the cottage. With ski equipment and clothing packed in the car, I can easily take the 127Mak, a small EP case and the AZ4. The Newt has a larger case and it pretty well takes most of the trunk space when we take it along.

Oh yes one more thing that was bothersome. In the cold weather, the focuser in the Mak was very stiff and made focusing a chore, but for some reason the Newt remained smooth for the entire time.

Eric