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RTMC solar binoviewing

Started by Jim Mahon, 05/27/2003 02:37PM
Posted 05/27/2003 02:37PM Opening Post
I had a chance to look through several Coronado-equipped scopes at RTMC, including my own, both with and without a shiny new Denkmeier Two.

I was put on the road to binoviewing by a huge gain in solar disk detail seen last summer when a friend dropped his Lomo viewer into my Genesis SDF with Coronado Solarmax 60 mounted. He had a pair of 17mm Nexstar plossls in the viewer, and despite the fact that I'd never been particularly fond of these eyepieces, the increase in contrast and definition on filaments, plage, and all sorts of granular detail (which I'm probably too lazy/new to h-alpha to know the proper terms for..) was simply breathtaking.

I'd begun to wonder as I waited for an ordered Denk Two whether I'd begun to exagerrate this effect in my own mind, and was sort of soft-pedaling the experience to friends. Absent the viewer to SHOW them, I didn't want to overstate the truth. This weekend removed any doubts.

The increase in visible detail on the disk/proms was absolutely stunning when a single eyepiece was replaced by either the Denk Two or the Denk standard a guy camping nearby offered for comparison. It didn't really matter much what eyepieces were used in the viewers - they all showed a huge improvement over any single eyepiece. Looked through some Coronado CeMax, TV Pans in 19mm and 24mm, Nexstar plossls, and UO orthos. As IÕd already ordered a Denk, comparing the two Denks was my interest. In retrospect, I should've tried to rustle up a couple of other brands for a quick comparison, but I didn't really want to be juggling various correctors and such with very little time for a careful comparison. There were no huge optical differences between the two other than an impression of a slight increase in sharpness when the Denk Twos replaced the Standards. Both were very good views!

The main point was that the gain in detail when going from cyclops to either viewer with any eyepiece set was very close to the gain seen when adding a second stacked etalon (the h-alpha interference filter) to the single-etalon instrument in cyclops mode. Not QUITE as good as the stacked rigs with their narrower bandpass, but very close and a whole lot cheaper even when figuring in the cost of a pair of premium eyepieces.

The stacked view plus binoviewers was even better, but I came away sure that a single etalon plus a binoviewer is the most cost-effective approach for me - and that not even taking into account night use of the viewer! Another guy who was present changed his mind on the spot and decided not to order a stacked etalon setup, but rather to order a single etalon outfit and a binoviewer instead. I admit to a twinge of envy when he walked over to a vendor and bought a pair of 24mm Panoptics on the spot...

All in all, an instructive weekend. Russ at Denkmeier told me my viewer will come in time for the Grand Canyon Star Party.


Posted 05/28/2003 08:06AM #1
I had a chance to compare some of these setups a week earlier at the NEAF, getting that same ohmygosh(!!!) experience when at the binoviewers. It was amazing how much more detail popped out when both eyes were used.

I too am now contemplating a binoviewer for my SolarMax90/T-max/BF30 setup (though I don't foresee myself stacking a 60mm with it). Russ L. and Bill D. are working with Coronado on an H-a optimized binoviewer, presumably based upon the Denk-two, and since I already have the 2" OCS (for another application), I'm already part-way there! shocked)


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