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Posts Made By: Roland Christen

January 14, 2006 05:03 PM Forum: Astro-Physics

AP Mach1GTO mount announcement

Posted By Roland Christen

To all,

The long-awaited Mach1GTO is the perfect "little brother" to our 900GTO and 1200GTO. It may be smaller, but it is every bit as sophisticated. It uses the same GTOCP3 Servo Control Box as the larger mounts and is driven by the same superb Swiss servo motors. Design goals emphasized compactness, light weight, rigidity and precision. We are delighted with the way these goals were met. Roland has been so excited in recent weeks, that I had to restrain him from spilling the beans too soon.

http://www.astro-physics.com/products/mounts/mach1gto/mach1gto.htm

The price has not been finalized, however the target price is $ 5,950. Production will begin in February 2006. Estimated delivery of the first mounts is the summer of 2006.

In mid-January, we will contact all of the people on our existing 400GTO/600EGTO notification lists, which we have merged together. We will provide information regarding the new mount and ask each person to confirm their interest in the Mach1GTO. If you are not already on one of these lists, you can sign up on our online notification form. In a day or two, we will replace the 400GTO and 600EGTO selections with Mach1GTO. In the end, all of these lists will be merged, so if you have signed up on any of them, you are on the list.

http://www.astro-physics.com/webdata/notify.html

We truly appreciate your support through all these years. Thank you.


Marj Christen
Astro-Physics, Inc
11250 Forest Hills Road
Machesney Park, IL 61115
Phone: 815-282-1513
Fax: 815-282-9847
www.astro-physics.com

February 6, 2006 05:14 PM Forum: Astro Binoculars

Large Budget Bino tests - and question for you guy

Posted By Roland Christen

Hi All,

I've been interested in getting a nice pair of large astro binoculars for some time now. I've looked at just about all the available brands at various star parties and have not found much of anything that is really constructed properly. Over the last two months I tested a number budget brands, all sourced from China, and one bino supposedly made in Japan. These are 70 and 80mm bino, 10x, 15x and 20x models. Here is what I found on almost all of them:

The 80mm binos without fail vignet internally because the prisms are too small. The entrance aperture limits the on-axis real aperture to 70mm, and the extreme off-axis to only about 45mm. The 70mm binos typically are vignetted to 60mm, and some as small as 45mm on-axis. Off-axis the illumination falls off drastically on the worst ones to about 35mm.

The next thing I found was that most of them have simple Kellner eyepieces with very poor off-axis star images, although on-axis they are not bad up to about 30 degree apparent field. The off-axis images have far more astigmatism, coma and lateral color that I can stand personally. However, what really surprised me about some of the models was the amount of spherical aberration in the front lenses. The undercorrection was so severe that only about 40mm of the full 80mm aperture was in critical focus, while the outer part of the lens formed an out-of-focus blur around each star. I have a pair of Minolta 10X45 binos with roof prisms that actually outperformed on of the 80mm binos on faintest stars visible.

lastly, I examined the coatings on the optics, including all the prism surfaces. Even the ones that were supposedly fully multi-coated had some of the internal surfaces coated with fairly high reflectivity coatings. Normally, an uncoated glass surface loses 5%, a single layer maybe 1.2%, and a multi-coated loses less than 0.5% per surface. Several of the fully multi-coated binos had prism surfaces with coatings that reflected over 5%, even though they were coated! And the eyepieces - well they had basically mediocre coatings.

About 2 weeks ago I received a pair of premium binos from a small Chinese maker which were said to be a direct copy of the 15x70 Fujinons. This sample was certainly a spitting image of that brand. The coatings are excellent all the way through, the eyepieces are nicely corrected over a fairly large field (not perfect at the edges), the spherical correction is miles better than any of the 70 and 80mm that I tested. Since I got them, the skies have been cloudy, but today it finally cleared up and I got a chance to test them on the stars.

My first test was a few minutes after sunset when the sky was still bright. The Moon was up, and the views were quite impressive with lots of crater detail even though these are only 15x. I noticed Mars nearby, and it was quite easy to see. I'm sure I could have picked it up earlier before sunset. As I panned back to the Moon, I noticed some faint stars already visible. It was the Pleiades, all members easily visible in the bright sky. This bino definitely has some excellent contrast. To say that I was pleased with these is an understatement.

Now the question. I have found what for me is an excellent bino. The company that makes them is a small outfit, and they cannot compete on price with the large makers which supply all the normal budget binos in their various configurations. These binos are basically twice the cost for the same size, but they actually work. Is there a market for something like this among cost concious amateurs?

Their specs are thus:
Total transmission over 90%. Eyepieces are special design, distortion free, flat field, sharp from center to edge. They are nitrogen filled, O-ring sealed, fog proof and waterproof. They were originally designed for extreme service for the military and can be lubed for operation from -40C to +70C. The only negative is that they are heavier than their budget bretheren, mainly because they do not use any plastic in their construction. Plus, they do not use ED or fluorite optics, something that would bump their price above $1k (it's not really needed at 15x unless you are truly picky and flush with cash). Estimated final price is around $350 if we were to import them, offer them for sale and be prepared to stand behind them warranty wise.

Is this realistic or am I blowing smoke (by the way, the owner of the company said that he doubted that amateurs would be willing to pay for what is basically a professional binocular).

Rolando

February 15, 2006 02:57 PM Forum: CCD Imaging and Processing/Deep Sky

M42 H-alpha

Posted By Roland Christen

Tried my hand at H-alpha last night. Scope was 160EDF operating at F5.7 with STL11000 and 10nm Ha filter. Image is approximately 1/4 size.

Rolando

March 31, 2006 06:52 AM Forum: Equipment Talk

Re: Surface Roughness & CP's

Posted By Roland Christen

All of the companies I work with use submerged polishing because it prevents differential temperature across the substrate, and thus reduces the tendency of a glass to spring after removal from the polisher.

RC

April 6, 2006 04:27 PM Forum: CCD Imaging and Processing/Deep Sky

M86 region

Posted By Roland Christen

It was actually clear for once here, so I had a chance to image 3 nights ago. This is the region around M86. The really cool galaxy in the upper left is NGC 4438.
160 EDF refractor at F5.7, STL11000.

Rolando


April 6, 2006 04:35 PM Forum: Astro-Physics

Re: Elephant in the room?

Posted By Roland Christen

>>Is there perhaps an elephant in the room>>

Beats me smile .

Rolando

June 10, 2006 12:49 PM Forum: Landscape Photography

Molokai

Posted By Roland Christen

A couple of images from a recent trip to the Hawaiian islands. We spent a couple of days just hanging and let the island sort of seep into our souls.

Molokai is the most undeveloped and least visited of the major islands. It represents most of what has been lost to development and tourism on the other islands.

It has only one small hotel, which it seems has not been updated since Captain Cook arrived. There are almost no tourist facilities, which makes it an intriguing place to visit for those who like to depart from the beaten path. The beaches are few and very empty of tourists. The western part of the island has wild surf almost year around, but there are a couple of small isolated beaches tucked into the coastline which offer superb swimming and snorkling. The people are friendly and you must make time for "talk story" whenever you visit any of the roadside fruit and veggie stands. It is not a place I would recommend to the first timer, but it can be a sublime experience to the seasoned traveler.

Rolando

June 14, 2006 01:25 PM Forum: CCD Imaging and Processing/Deep Sky

M64

Posted By Roland Christen

Shot this one two days ago. 5 exposures of 5 minutes each stacked in MaximDL. SBIG STL11000 camera, 160EDF refractor at F7.5

Rolando

July 19, 2006 01:16 PM Forum: Astro-Physics

New Product Announcement

Posted By Roland Christen

Hi All,
We just posted all the info for our new binocular line on the web site
http://www.astro-physics.com/

We have them in stock for immediate delivery.

Roland Christen

July 31, 2006 11:39 AM Forum: CCD Imaging and Processing/Deep Sky

M8 M20 IC4685

Posted By Roland Christen

Here is a link to some cool summer objects, probably the second most photographed objects. This stunning image was taken by Dave Jurasevich (optics by me own hands grin ):

http://www.starimager.com/Image%20Gallery%20Pages/Hydrogen%20Alpha%20Images/m8_m20_ic4685.htm

Rolando