Horsehead in H-AlphaPosted By Roland Christen |
Very nice detail. Smooth and sharp.
RC
RC
Posts Made By: Roland Christen
November 4, 2005 03:16 PM
Forum:
CCD Imaging and Processing/Deep Sky
November 7, 2005 07:04 PM
Forum:
CCD Imaging and Processing/Deep Sky
M45, Merope and IC349Posted By Roland Christen |
Closeup Merope and IC349 - 50 images luminance 10" F14.6 Mak-Cass with RGB color added from 160EDF and STL11000
Roland Christen
Roland Christen
November 12, 2005 09:43 PM
Forum:
CCD Imaging and Processing/Deep Sky
RosettePosted By Roland Christen |
This is a cropped portion of the middle at 1/2 size.
I am really beginning to like this camera. It seems to be a perfect fit to the 160EDF F5.7 focal ratio. With its 9 micron pixels, I can still get excellent resolution on almost all deep sky objects without having to resort to a much larger aperture. It has a very nice field size which eliminates the need to do mosaics. I don't have to mess with blooming stars, although I do miss the low noise and fast response of my ST10XE. Maybe in the future they will develop chips that are ideal in all respects, but for now I'm having lots of fun with this one.
By the way, anyone have any ideas for another object to image? I have to give this camera back soon
and really appreciate Ray Gralack for lending it to me for these tests.
Rolando
I am really beginning to like this camera. It seems to be a perfect fit to the 160EDF F5.7 focal ratio. With its 9 micron pixels, I can still get excellent resolution on almost all deep sky objects without having to resort to a much larger aperture. It has a very nice field size which eliminates the need to do mosaics. I don't have to mess with blooming stars, although I do miss the low noise and fast response of my ST10XE. Maybe in the future they will develop chips that are ideal in all respects, but for now I'm having lots of fun with this one.
By the way, anyone have any ideas for another object to image? I have to give this camera back soon
and really appreciate Ray Gralack for lending it to me for these tests.Rolando
November 22, 2005 03:57 PM
Forum:
CCD Imaging and Processing/Solar System
the Big picturePosted By Roland Christen |
Gorgeous picture.
RC
RC
November 30, 2005 01:19 AM
Forum:
Astro-Physics
Finally! New AP Ad in S&T!Posted By Roland Christen |
There will soon be some new products. You will see 
Rolando
Rolando
December 1, 2005 05:46 PM
Forum:
Binoviewers
New Baader BV'sPosted By Roland Christen |
Yes, I have checked them out very carefully since we carry all Baader accessories at Astro-Physics. They are the same as other Chinese made binos, with some Baader touches. The prisms are not very accurate, showing astigmatism if you try to use high power eyepieces directly. This is the same with other low cost Chinese binos also, but they will work adequately if you place a Barlow before the bino and do the magnification before the light beam enters the prism path. Then, with low power eyepieces you will get a high power view that is free of major astigmatism. The overall transmission is not bad, but as expected the beam splitter does not split 50-50, but seems to be more like 30 - 70. This could be just in the unit that I have and maybe others will be different yet.
Precision it is not. Affordable and useable it is. We, at Astro-Physics have not decided yet whether to carry offer it for sale.
Roland Christen
Precision it is not. Affordable and useable it is. We, at Astro-Physics have not decided yet whether to carry offer it for sale.
Roland Christen
December 9, 2005 12:58 AM
Forum:
Refractors
Stellarvue 102BVPosted By Roland Christen |
The term ED stands for "Extra low Dispersion". It applies the glaases with V numbers above 75. Not all ED glasses can be used to make apo lenses. Some ED glasses can only achieve achromat corrections.
Roland Christen
Roland Christen
December 22, 2005 05:27 PM
Forum:
Chinese Optics Imports
INCREDIBLE POST ON CN "the beat goes on"!Posted By Roland Christen |
It's possible that something is coming from Chinese sources. I don't think it will be as cheap as originally projected. It may even be a bit smaller diameter, but better corrected than a doublet ED lens. I'm guessing a 90 - 95mm fluorite refractor for about $990 to $1200 depending on what goes with it.
Anyone else willing to guess?
RC
Anyone else willing to guess?
RC
December 28, 2005 06:15 PM
Forum:
Eyepieces
5mm Tak LE apartPosted By Roland Christen |
The design is basically a simple Ortho fed by a Barlow (i.e. a Barlowed Ortho). You can do the same with any ordinary Ortho and 1.25" barlow lens.
The Barlow presents a relatively long focal ratio to the Ortho elements, and thus they will have correspondingly better off-axis performance. This is the trick behind every new short focus eyepiece available today. If you want 50 - 55 degree apparent field, a simple Ortho will do. If you want 60 - 70 degree, then an Erfle variation is used in the positive set. The Barlow serves to clean up the otherwise horrible off-axis performance of a standard Erfle. The Barlow is nothing special, and any good quality lens will work.
Roland Christen
The Barlow presents a relatively long focal ratio to the Ortho elements, and thus they will have correspondingly better off-axis performance. This is the trick behind every new short focus eyepiece available today. If you want 50 - 55 degree apparent field, a simple Ortho will do. If you want 60 - 70 degree, then an Erfle variation is used in the positive set. The Barlow serves to clean up the otherwise horrible off-axis performance of a standard Erfle. The Barlow is nothing special, and any good quality lens will work.
Roland Christen
December 29, 2005 06:00 PM
Forum:
Pictures of Me and My Telescope and........
My daughter and what Santa broughtPosted By Roland Christen |
Wow! What a cutie. The scopes nice too.
Rolando
Rolando
Funding Member
