Posted By William Paolini
SCOPE: 10” f/4.7 Dob.
OBSERVING: 80% time spent mid-high power lunar, planetary, globulars, doubles. 20% time in low power mode scanning. I’m in light polluted area so rich field scanning is generally disappointing and DSO is a waste of time.
EYEPIECES: My collection runs from 40-82 degree afov eyepieces. They are Nagler’s, Siebert’s, UO HD’s, UO Erfles, RKE’s, TV Plossls, TV Wide Field.
HABITS: I have always been attracted to the wider fields. The old 24 TV Wide Field has always been a favorite. However, nowadays I rarely use it. The UO Super Erfles usually get more use for longer focal lengths. Primary reason is the contrast is incredible and the color is extremely neutral. They just put up a “cleaner” image so it’s easier to forget the glass you are looking through is there. On higher power work, the Naglers were always first. And they usually go in still, but now only for an initial “wow” – akin to the 1st drag on a cigarette. After that’s over, time to get to business so they come out in favor of a sharper more neutral image. For me the UO HD’s put up the cleanest clearest image. But the smaller afov usually get’s to me, and I move to the Sieberts which stay neutral in color, but not quite as neutral as the UO HDs. Actually, not sure if neutral is a good word, more “white.” For some odd reason, the whites seem whiter in the HDs, almost a white cast to the illuminated sources in the fov. I find an afov of 82 degrees is nice for pleasure, but for business 60-70 seems to work the best…more towards 70. If the high power work is on an extended object line the Moon or Jupiter or Saturn with their surrounding moons, the small afov of the HDs is not a drawback in the Dob since plenty of navigation references in the fov to push the scope back to the point of interest. However, for Globulars or doubles, the HD’s small afov is a challenge in the Dob, especially when up around 300-500x. So then get myself back to the Sieberts which run 60-70 afov (Ultras and Star Splitters). One thing I have noticed in every observing session, always wishing the HD’s had a wider afov! So there is something about the quality of the image they put up that obviously strikes me more than any of the other designs and brands. So the “color” the ep puts up is evidently very important to me, as is the point sharpness (I notice also always wishing the HDs put up as sharp of a point as the Siebert Star Splitters). Oddly also, weight seems to be important. I mean if the ep is too light I tend to think it is cheap which indirectly influences its use. For instance, the RKEs have that black aluminum barrel. I switched those out for chromed brass barrels which made them look better, feel better, and actually handle better, especially in the cold. The TV Plossls are just too small, plus their imagery is the worst of the collection (just a grainier image in comparison). So those have fallen into almost complete disuse. So I guess it’s when the mix of performance factors are present which make it easiest for me to completely ignore the eyepiece and concentrate solely on the object is what makes me reach for which ep first. In my present collection that is usually the Siebert Star Splitters first, UO HDs second.