MK 67 vs 6" F-8 Achromat

I just ordered an MK 67 Deluxe from ITE, special pricing @ $995. The reviews I have read are generally positive. I was originally thinking of purchasing an M715, but the price difference between the reduced MK 67 and the M715 was just too much to justify 1 extra inch of aperture, although the central obstruction of the M715 is smaller (25% vs 33% in MK 67).

I primarily observe planets. Any first hand experience as to how the MK 67 should compare with my present scope, an AR 6 (6" F/8 Achromat). I belive the the AR 6 is very well corrected, my own observations through a Ronchi test grate do not show discernable over or under correction.

Will the achromatic nature of the MK 67 give better high power planetary views, or will the Central Obstruction give me inferior views.

I'll know soon enough when I take delivery, but I'd like to know of the experiences of any readers.

Thanks.

The MK 67 Deluxe will perform much better than the 6" achromat refractor - you will not have chromatic abberation, which degrades the images of the refractor more than the contrast lost from the central obstruction of the Maksutov.

I also bought an MK 67 from ITE (took almost 7 months do be delivered, partly due to the US west coast dock strike of late 2002 - ouch...the wait was worth every day) superb optics, pinpoint stars, great planetary & lunar views.

I suggest buying a premium 2" diagonal, & add a Telrad unless you are going to use a GOTO mount...the 10 X 50 finder scope has a fairly narrow field of view (I use the Telrad to get close to dim objects, and use the finder to center the scope.

The scope does take a while to temperature stabilize, but the views are worth the wait.

Additionally, I had a very good experience with ITE...Bill answered all of my questions, and was a peasure to do business with.

Greg Martin

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I've done some fairly close comparisons of my MN 56 with a 5" D&G f/12 refractor. The MN 56 was just as sharp, and I suspect sharper than the D&G. The D&G is observably brighter.

I should note that at f/12 the D&G will have considerably less color than the 6" f/8 which is approaches being a short tube.

Depending on your climate, my biggest concern with the MK 67 would be cool down.

No doubt the M715 would be a better choice, however, at more than twice the price I can't justify it (especially to my boss - I mean wife) ($2345 standard / $2845 deluxe). My main concern is that I not take a step backward from the 6 " Achromat. The smaller tube will likely get me out more often.

What I'd really like is the M91 (9" F/13.5 MakCass w/ 26% co). Have to wait for the wallet to catch up to the appetite.

Seriously though, the M715 was clearly my top choice, the MK 67 was simply a more "economical" compromise.

I hope I'm happy. I'll let you all know.

Thanks to everyone who responded to my post.

I picked up the new scope yesterday. No curse. Saturn was awesome. I will follow up with some info on the scope and my purchase experience if anyone is interested.

Thanks again!