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Posts Made By: William Paolini

June 8, 2006 01:16 PM Forum: Eyepieces

Wide field, Deal or No Deal?

Posted By William Paolini

Great question Floyd!!

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.

June 19, 2006 06:52 AM Forum: Eyepieces

Re: threats to the validity of eyepiece comparison

Posted By William Paolini

"If I hadn't belived it, I would have never seen it!"

Should we consider all of history just "entertainment?" Afterall, it's just the recordings of observers, with all their subjective biases.

It is impossible to find an observer without bias. Anyone saying they are objective is a bias itself.

To say that the observations of another should be for entertainment purposed only, is just plain wrong (both in the moral and scientific contexts).

If you take a close look at many objective double blind studies done in the research community, you will find the same things, human bias, ignorance of confounding variables (more biasing, both inadvertent and purposeful), and inappropriate extrapolations.

In any review of research or observations of another, the appropriate methodology is for the reader to find the areas which are of pertinence to their inquiery and evaluate that in the context of their need. One must be able to extract that which is needed from the documented observation. This is the key skill. This is how all observations provide value.

All observations are good. None are to be taken as entertainment.

June 19, 2006 07:26 AM Forum: Eyepieces

24mm Panoptic vs. 28mm Siebert Ultra

Posted By William Paolini

I think this decision will have more to do with other factors than just EP performance, because of the great difference in price mostly and how well you can handle your own expectations.

I don't have a Pan, just its predecessor, the 24mm TV Wide Field. I have a few Ultras, 15mm and smaller FL though. So really can't do an apples to apples comparison at all. However, the two EPs do leave me with distinctly differing feelings after use. I come away slightly more "pleased" when I use the WideField, but it is never "transparent" -- i.e., always realize I'm looking thru an EP-window. The Ultra, on the other hand, leaves me more of a memory of what I observed rather than the glass I'm observing through.

But all other things aside, both EPs are good. And after you forget about the EP you are using and concentrate on the business of observing, you have to ask yourself if you would have been happier with 2 EPs instead of 1 for the same money?

We all want the best. The "expectation" to contend with is do we all need the best? A difficult issue.

In another thread, someone referred to William Hershel. Take a moment to read a small part from his log regarding volcanoes on the Moon (http://www.space.edu/moon/timeline/1700s/1787-Herschel.html). It is really refreshing. At no point does he mention the instrument he is using, nor the eyepiece design. Seems for some reason, this observer's focus is solely on that which he is observing. Really nice to read. Plus in the 1st para he understands the limitations and biases of his own mind in the process.

I don't know, but after reading this, I'd go for more observing tools (i.e. EPs) over just having one. Sometimes, having one more perspective in a slightly different magnification, let's us see more.

Good luck with the quandary smile

June 21, 2006 06:46 AM Forum: Eyepieces

eyepiece collection

Posted By William Paolini

Did you mean a UO 7mm Ortho or Plossl?? If the Ortho, keep it!

The 7mm Nagler I have for the same scope...it performs wonderfully. 6 and 7mm seems to be a magic fl for this scope in my viewing area (D.C.).

The 35 Pan and future 19 Pan are great for low powers. Quite frankly, I don't see any need for anything else in between those fls. So the question becomes, the need to fill between 19mm and 7mm, and something a tad higher power perhaps than the 7mm.

I have the 5mm Nagler, and not as satisfied with the image as I am with the 5mm UO HD Ortho, or a 5mm Siebert Star Splitter. But, if you like building a "family" the 5mm Nagler, or 4.8mm T1 is not bad, then you'll have 2 Naglers. But these days I never reach for the 5mm Nagler since the others put up much better images.

If you like the imagry in the TV Zoom, then you are set for that filler between the 19 and 7mm. Otherwise and 11mm Nagler.

So you have some good stuff in the key FL positions there. The Sirius Plossls I personally don't like...actually I don't like Plossls much period...too plain jane performance wise. Would rather have a good Erfle than a Plossl any day.

But anyway, for me the "gems" of your collection are:

7mm Nagler
Nagler Zoom
19mm Pan (future)
35mm Pan

if the UO is an Ortho, then that's a gem also. Looking at the above, I think it still begs for an 11mm Nagler smile

The rest you can keep and swap as time goes by for variety smile


June 21, 2006 08:32 AM Forum: Eyepieces

Edmunds RKE 28mm

Posted By William Paolini

Agree...that is quite an EP for the price. Always puts up a good view.

btw - the EdmundsOptical site has a lot to be desired in terms of an easy navigatable interface. The RKEs are there. Try this url...
http://www.edmundoptics.com/onlinecatalog/displayproduct.cfm?productID=2075&search=1

Happy Observing!
-Bill

June 22, 2006 06:57 AM Forum: Eyepieces

So guys, what do you think about this situation?

Posted By William Paolini

Floyd,

If what looks like is happening is happening, then I think it would be appropriate to put this entire thread under the root of the thread in question, retitling this thread so latecomers read it.

Alternatively, you put a moderator comment under that root summarizing this thread's contentions for the protection of other AMarters or referring to this thread for further important information.

Third option would be to do selective deletions of each post in the thread taking out the inappropriate stuff so only items relative to topic of fixing scratches remains and just annotate in each of those that some text removed by moderator for legal reasons. I have seen this in other forums. Actually, this may be the "safest" and most appropriate approach.

-Bill

June 30, 2006 12:40 PM Forum: Eyepieces

Eyepiece Recommendation

Posted By William Paolini

The RKE's already recommended are good. But only 45deg afov, but in truth it looks a tad more to me. I barely notice a difference between the 8mm RKE and the 8mm TV Plossl which is supposed to be 52deg. But RKE after the 8mm, only has the 12mm.

The Siebert Star Splitters have 60deg afov and very sharp field stop. Available in virtually any fl you want. But they are $99 which is a bit over your range. On the plus side though, since Harry Sibert makes binoviewers, I sure he would ensure you get a perfectly matched set. So something to think about. I have these eps and they are very sharp.

Finally, for the cheapie route, there is this oldie I came across in 10mm that really performs quite well. Called a "10mm MA Long Eye Relief" eyepiece. No name on it. People have it on Astromart. I recently put up an add for them and got a few people having them. So you could get those for about $25 each used from AMarters. Send me a private email if you want to know more about this and I can send you some pics.

Other than that, Siebert has what he calls "Performance" series which are $49 and supposed to be 65deg. I have no experience with those though. Call Harry and maybe he'll give you a 30-day back on these...I know he does on other products, just not sure on these.

-Bill

July 3, 2006 01:50 PM Forum: Beginning Astronomy?

Need Help Triple Image

Posted By William Paolini

Well this does sound strange. Use the eyepieces in someone elses scope and see if they do the same thing. Unlikely though that all the eyepieces would be defective in the same way to cause the problem you are seeing.

Are you wearing glasses when you view through the scope? Only thing I could think of is that you have bifocals on and the image is bouncing off your glasses and back onto the eyepiece causing the 2 ghosted images.

July 6, 2006 01:23 PM Forum: Eyepieces

Barlow vs. high mag EPs

Posted By William Paolini

If you buy a good quality barlow, there is no readily apparent affect to the image vs a high power ep. I have a variety of eps and have done direct compares between the high power and the low power + barlow yielding the same Fl as the high power. I have not yet been able to detect a difference. So even the light loss from the extra glass is insignificant enough as not to reduce dimmest stars in the field. FYI, I have a 10" dob, f/5, and use a Klee 2.8x barlow.

I do notice however the afov does alter on some eps under barlow. The TV Powermate and Siebert Telecentric barlow are supposed to eliminate this alteration to the basic characteristics of the ep.

July 12, 2006 10:51 AM Forum: Eyepieces

Leitz 30 mm 88° WwPlanokular WOW!

Posted By William Paolini

Are they worth it? I have never looked thru one. I know I will probably be crucified for saying this, but hey...I'd "extrapolate" that it is probably a tad...little bit...overpriced. 8O Back in the ancient days when men were men, cameras had film, and dinos roamed the earth, Leitz had quite a reputation for a well build camera...and way expensive. Most internals were hand filed and made. You could stand on one of these without hurting them at all. Funny thing was, the Japanese cameras of the day perfomed better...meaning had much more accurate exposures and shutter timinghs since it was cookie-cuttered to tight specs in a factory. Go figure, robotics outdoes hand crafting.

It,s big, lots-o-glass, heard it performs well. Even if it was perfect...almost 3 times the cost for 6 more deg of afov than a Nagler.... shocked for me, the stars better sing and dance thru that thing to be "worth" that.