Posts Made By: Ron Bee

Is there a list of objects discovered by William Herschel? If so, can someone point me to it? Otherwise, I can attempt an arduous compilation from SEDS, Uranometria, etc. :-(. Also, off-hand, does anyone has the total number?

Thanks in advance,
Ron B[ee]

Someone posted this cool link to the effect of seeing on Talking Telescopes.
http://www.cmc.ec.gc.ca/cmc/htmls/seeing_e.html

Ron B[ee]

No, not the omnipotent "Q" from Star Trek... please read on...

Ok, no one seems to like the terms "semi-APO", "neoachromat". I realize that we've discussed the use of these terms. But I'd like to present a hypothetical scenario and perhaps define "quasi-APO". And please, no semi-pregnant argument ;-) that I think have not been
discussed (or had been discussed before my time ;-). This discussion is limited to visual use.

Let's start from some dim and mystic past discussions and let's use my favorite 4-inch aperture as example. I recall someone said that chromatic aberrations (CA) is:

CA(4-inch f/20 achromat doublet) = CA(4-inch f/8 APO doublet)

If f/20 is incorrect, please supply a correct number. But it doesn't matter in this discussion. First everyone would agree that an 4" f/5 achromat is quite colorful compared to the 4" f/10 achromat (eg. Synta). And I would assume that the 4" f/10 achromat would be more "colorful" than an f/20 achromat. If you agree with this, then I assert that there exists a zone of **perceived** color correction that "looks" better than f/5 but not good enough like an f/20. Why then can't "quasi-APO" (Q-APO ;-) be used to describe a refractor that falls in-between the equation above? Also, Ed Ting, Todd Gross and other experienced reviewers have mentioned this "property" (of semi-APO) in more than one of their reviews.

I don't know if optical theory allow for this "twilight zone".

Thanks,
Ron B[ee]

Well, I'm so excited about my new book that UPS just dropped off, Observing Handbook and Catalogue of Deep-Sky Objects, by Skiff and Luginbuhl. I'm just scanning through it and I think this is better than my 3 volume Burnham books already. Quickly on the things I'm thrilled with shakes:

o description of objects by different aperture.
o SB number, I no longer need my slide rule ;-).
o photometric data, more speed limit test for my Light Cup
o organized by constellation - just like Burnham books.

No darn !@#$%^&* moon is gonna stop me from trying out one of the objects tonight!

Wish list for the next revised standard version: description of objects through a 10.2cm APO ;-). Or if the authors can give me a go-ahead to substitute 15cm for 10.2cm ;-).

Off-hand, this is a book that should be hung on the tripod of every amateur astromer's equatorial mount ;-), you know like those yellow pages hanging at every public phone boothes! The best part: the book is so affordable.

Ron B[ee]
PS If you don't see me post for a while, you'd know what I'm busy on ;-).

http://members.cox.net/ronby/Observations/082902.htm

Enjoy,
Ron B[ee]

Before you guys with the 5", 6", and larger cast the first aperture stone, please here me out....

I was catching up on my reading of the Oct. issue of S&T when I came across a most interesting article about astronomy in Mexico. Then, my 4-inch short sighted eyes caught something. "A keen planetary observer, [Francisco Javier] Escalente [1887-1972] spent 55 years observing Mars [my favorite planet] from his home in Mexico City, using a 4-inch Zeiss f/21 refractor. In 1960, he and fellow member
Elpidio Lopez wrote a landmark 620-page book on the red planet, filled with numerous highly detailed drawings that they had made at the eyepiece". [S&T Oct 2002]

Boy, was it an astro-orchestra to the ears of my 4" TV-102 Light Cup. The 4-inch instrument is indeed a serious planetary instrument! I can only imagine the wealth of material in the elbow busting weight of his 620-page book! Surely, if the 4-inch weren't serious, it couldn't have produce so much data. Also, he was honored by the
International Astronomical Union by having a 49-mile crater situated along the Martial equator at longitude 245d christened with his name.

Now, I have escalated my quest to find out more about this
fascinating astronomer. Unfortunately, Google search turns up nothing. Does anyone have any more info? Anyone else knows who used a 4" instrument to study and publish papers on the planets in the past? Well, the next time I'm in Mexico, I'd sure visit the library!

So let us all who owns the small telescopes (4" refractor, 4" MCT, 4.5" Newt, 5" SCT, 5" MCT, etc.) not forget to
"seriously" observe the red planet next year.

Ron B[ee]
PS Feliz aniversario, SAM y felices Fiesta Patrias!

Before you guys with the 5", 6", and larger cast the first aperture stone, please here me out....

I was catching up on my reading of the Oct. issue of S&T when I came across a most interesting article about astronomy in Mexico. Then, my 4-inch short sighted eyes caught something. "A keen planetary observer, [Francisco Javier] Escalente [1887-1972] spent 55 years observing Mars [my favorite planet] from his home in Mexico City, using a 4-inch Zeiss f/21 refractor. In 1960, he and fellow member
Elpidio Lopez wrote a landmark 620-page book on the red planet, filled with numerous highly detailed drawings that they had made at the eyepiece". [S&T Oct 2002]

Boy, was it an astro-orchestra to the ears of my 4" TV-102 Light Cup. The 4-inch instrument is indeed a serious planetary instrument! I can only imagine the wealth of material in the elbow busting weight of his 620-page book! Surely, if the 4-inch weren't serious, it couldn't have produce so much data. Also, he was honored by the
International Astronomical Union by having a 49-mile crater situated along the Martial equator at longitude 245d christened with his name.

Now, I have escalated my quest to find out more about this
fascinating astronomer. Unfortunately, Google search turns up nothing. Does anyone have any more info? Anyone else knows who used a 4" instrument to study and publish papers on the planets in the past? Well, the next time I'm in Mexico, I'd sure visit the library!

So let us all who owns the small telescopes (4" refractor, 4" MCT, 4.5" Newt, 5" SCT, 5" MCT, etc.) not forget to
"seriously" observe the red planet next year.

Ron B[ee]
PS Feliz aniversario, SAM y felices Fiesta Patrias!

I just got a new brain spinning book, Telescope Optics by Rutten & van Venrooij. I thought the book was out of print earlier, but notice that this is the 5th printing dated 2002! At any rate, a quick glance especially at the software section tells me that the materials are dated (eg. DOS programs ;-). Now perhaps, I might be able converse with the optics experts and more importantly understand just a wee-bit more, albeit at an elementary grade school level :-(. One thing is for certain: the book has already shown me what I thought the 0.1% I knew about optics is actually a -20% (yes negative sign) knowledge :-(. I still would love a book by Roland and/or Thomas ;-).

Anyway, the authors used the terms "semi-apochromat" or "half-apochromats" and no one seems to have a problem with this, most interesting. They used these terms to state that the secondary spectrum is reduced to 1/4000 the
focal length. Umm, most revealing. The authors then talked about Apoklaas objectives which "utilizes two special glasses, reducing its secondary spectrum
to 0.00012f)."

What is this Apoklaas? I've never heard of it or seen on the web. Is it something that was popular at one time but now no longer being made. Can someone provide more description?

Thanks,
Ron the elementary optical (but slowly rising from inept) B[ee]

Last year, one of the surprise on Jupiter was the dark barges. I have a couple of questions:

o Was the dark barges discovered by amateur, professional, or spacecraft? If amateur, does anyone know who and/or what instrument was used in the discovery?

o Was it the first time dark barges has been seen on Jupiter? Or has there been other occurences throughout history?

Thanks,
Ron B[ee]

http://members.cox.net/ronby/Observations/091002.htm

Enjoy and please don't laugh ;-).

Ron B[ee]