| Don Allen |
| (sage) |
| 12/23/08 01:22 PM |
Contrast Enhanced Diagonal
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Has anyone tried one of these diagonals by Burgess Optical? He announced the product in his user group a few weeks ago.
| StarStuff1 |
| (scholastic sledgehammer) |
| 12/24/08 04:46 PM |
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Re: Contrast Enhanced Diagonal
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Hi Don,
Guess you noticed that one of the group members is planning on testing a CED1 tomorrow night using 91mm and 128mm apos.
Could be interesting.
| Don Allen |
| (sage) |
| 12/24/08 08:51 PM |
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Re: Contrast Enhanced Diagonal
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Had not heard. Looking forward to the report.
| Telescopeman54 |
| (Vendor - Trapezium Telescopes & Services, LLC.) |
| 12/24/08 11:51 PM |
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Re: Contrast Enhanced Diagonal
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I am waiting for mine. Of course, that will mean several weeks of more rotten weather!
Steve
| Don Allen |
| (sage) |
| 12/25/08 12:27 AM |
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Re: Contrast Enhanced Diagonal
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Does bad weather come because you buy a scope or because someone sells you one...that is the question. Either way it would appear the retailers of astro gear must be doing well this winter.
| rmollise |
| (Post Laureate) |
| 12/25/08 10:52 AM |
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Re: Contrast Enhanced Diagonal
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Quote:
Has anyone tried one of these diagonals by Burgess Optical? He announced the product in his user group a few weeks ago.
How does a diagonal work this magic?
| Paul G |
| (Carpal Tunnel) |
| 12/25/08 12:57 PM |
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Re: Contrast Enhanced Diagonal
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Quote:Quote:
Has anyone tried one of these diagonals by Burgess Optical? He announced the product in his user group a few weeks ago.
How does a diagonal work this magic?
Not sure. Burgess didn't respond to a request for information on reflectivity as a function of wavelength.
Tom Trusock
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| () |
| 12/25/08 01:08 PM |
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Re: Contrast Enhanced Diagonal
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I also, am wondering.
| Jim7728 |
| (Postmaster) |
| 12/25/08 01:29 PM |
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Re: Contrast Enhanced Diagonal
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Okay, it's got my attention.
http://tech.groups.yahoo.com/group/BurgessRefractors/message/13515
Particularly the CED2 for achromats.
But, we'll have to wait and see. Thanks for the heads up!
| shams42 |
| (sage) |
| 01/19/09 01:15 AM |
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Re: Contrast Enhanced Diagonal
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Any news about this product? I'm interested in the CED2. How could this correct for CA?
| coliea |
| (member) |
| 01/19/09 03:01 AM |
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Re: Contrast Enhanced Diagonal
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Quote:
I also, am wondering.
Me too - when it comes to spin, Bill's the master
| Dennis Sakva |
| (Pooh-Bah) |
| 01/19/09 07:33 AM |
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Re: Contrast Enhanced Diagonal
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Probably it's a specifically designed dielectric mirror that works by not reflecting deep violet thus increasing contrast of achros.
| Covey32 |
| (scholastic sledgehammer) |
| 01/19/09 07:35 AM |
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Re: Contrast Enhanced Diagonal
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In the old west his wagon would have had "Magic Elixir" written on the side of it and he would have been called a "pitchman".
Of course...somebody has to do it.
Why not him ??
| Jim7728 |
| (Postmaster) |
| 01/19/09 08:29 AM |
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Re: Contrast Enhanced Diagonal
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Still not sure how the CED works other than it's perhaps a star diagonal with some kind of MV coating(?) I found one user's first impression report.
http://tech.groups.yahoo.com/group/BurgessRefractors/message/13668
| nighty |
| (sage) |
| 01/19/09 09:15 AM |
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Re: Contrast Enhanced Diagonal
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This will not be the technical report that is desired, but Venus and the moon looked so much better during the brief "first light" that I did not regret my purchase. This is the most expensive accessory that I have purchased, so the above statement is a sincere recommendation.
To me, it seems to be a simple device that lets you see more detail with the equipment you use regularly.
It was used with a BO 1278 and compared to a quality diagonal with a WO minus violet filter. I was impressed.
| Covey32 |
| (scholastic sledgehammer) |
| 01/19/09 09:21 AM |
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Re: Contrast Enhanced Diagonal
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Polarizing filters are generally cheaper.
| Sol Robbins |
| (Carpal Tunnel) |
| 01/19/09 09:59 PM |
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Re: Contrast Enhanced Diagonal
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I have both the CED1 and CED2 and am testing them out. Though Bill has not given me any details, I believe these diagonals are special purpose with special benefits depending on what you're observing in concert with the aperture of a scope.
That said I know that they act as interference filters. In diagonal form, they are purported to be a 1/10 wave after coatings. Additionally, their 45 degree angle negates any reflections that occurs when using the screw on the eyepiece type of interference filter. The CEDs really reduce eyepiece scatter when viewing the Moon.
I can also compare these diagonals to one-off infereference filters I have with known, at least to me
, peaks of transmission. I have been using interference filters for years and have approximately 25 of them. Most of them for beta testing.
To compare these to run of the mill filters or polarizers is somewhat of a mistake.
The best thing out of the box about these diagonals are how well collimated they are simply inserted into my refractor. Both diagonals I received are spot on. I can't say that about any other diagonal I have ever owned.
More later.
Best,
| shams42 |
| (sage) |
| 01/20/09 09:17 AM |
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Re: Contrast Enhanced Diagonal
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I'm in the market for a 2" diagonal to replace the 1.25" one that came with my telescope. I assume my stock diagonal has relatively poor reflectivity. Do you think I would be better off with a CED2 for planetary and DSOs, or a more general-purpose brighter 2" diagonal and a filter, such as a Baader semi-APO, for planetary and lunar viewing?
To restate, do you think the CED2 would be brighter on DSOs than my stock diagonal? I don't have a lot of aperature to spare (4.7"). Is it a good compromise piece, or would I be better off with something else?
As a newbie, I've viewed mostly DSOs so far, but this partly reflects the relative unavailability of planetary targets right now. I don't yet have a sense of what my "specialty" will become.
| Sol Robbins |
| (Carpal Tunnel) |
| 01/22/09 07:28 PM |
| Attachment |
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Re: Contrast Enhanced Diagonal
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Hi,
I had good conditions for observing Venus with an enhanced aluminum star diagonal, the CED1 and the CED2. I took my Chromacor II out of my 6" f/8 achromat.
I made sketches using each diagonal. I tried to sketch as accurately as I could. Anyway, hopefully this might give some kind of idea of what the differences in overall detail may be when viewing this specific object
Below is with a stock star diagonal.
Best,
| Sol Robbins |
| (Carpal Tunnel) |
| 01/22/09 07:29 PM |
| Attachment |
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Re: Contrast Enhanced Diagonal
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Sketched observation with the CED1.
| Sol Robbins |
| (Carpal Tunnel) |
| 01/22/09 07:30 PM |
| Attachment |
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Re: Contrast Enhanced Diagonal
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Lastly, with the CED2.
| Tamiji Homma |
| (Pooh-Bah) |
| 01/22/09 10:59 PM |
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Re: Contrast Enhanced Diagonal
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Hi Sol,
Thank you for nice sketches. I found it very interesting. It is difficult to pick up details from super bright Venus surface.
I am curious how you see the full Moon surface with CED2.
It looks like the CED is interesting product.
Tammy
| Sol Robbins |
| (Carpal Tunnel) |
| 01/22/09 11:25 PM |
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Re: Contrast Enhanced Diagonal
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Thank you very much Tamiji.
THe Moon will have to wait as will Jupiter. These objects may prove to be interesting as test subjects.
It was interesting that with the CED2, light scatter from the air and/or the eyepiece was eradicated.
Other than the CA inherrent in an achromat, Venus had a very clean appearance.
Best,
| Tamiji Homma |
| (Pooh-Bah) |
| 01/23/09 12:59 AM |
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Re: Contrast Enhanced Diagonal
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Quote:
THe Moon will have to wait as will Jupiter. These objects may prove to be interesting as test subjects.
It was interesting that with the CED2, light scatter from the air and/or the eyepiece was eradicated.
Other than the CA inherrent in an achromat, Venus had a very clean appearance.
Hi Sol,
Yes, long wait for Jupiter.
Did you notice any difference in brightness (transmission) from center to edge? I am guessing there is some gradient in coatings from center to edge. It's just my wild guess.
I may be totally off base
Recently, I compared very good wide AFOV eyepiece to excellent planetary eyepiece in light scatter and contrast. I saw Venus something similar to the first sketch (stock diagonal one) in very good wide AFOV eyepiece.
Then I saw something similar to your sketch with CED2 in excellent planetary eyepiece. I was a little bit stunned at the obvious difference. I realized that I've been missing something.
I observed similar result with the full Moon. I saw more details on bright Moon surface with the planetary eyepiece. I used to stay away from the full Moon but not any more
I haven't repeated the observation yet so I can't say it for sure, just seeing difference or something.
That's why I was curious about the full Moon. Let us know how you see when you get a chance to observe the full Moon with CED.
Tammy
| Sol Robbins |
| (Carpal Tunnel) |
| 01/23/09 01:38 PM |
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Re: Contrast Enhanced Diagonal
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Quote:
Did you notice any difference in brightness (transmission) from center to edge? I am guessing there is some gradient in coatings from center to edge. It's just my wild guess.
I may be totally off base
Recently, I compared very good wide AFOV eyepiece to excellent planetary eyepiece in light scatter and contrast. I saw Venus something similar to the first sketch (stock diagonal one) in very good wide AFOV eyepiece.
Tammy
Tamiji,
I did not see any differences in brightness anywhere in the FOV. Venus moved around quite bit as I can't accurately polar align when its still light outside.
Thanks,
| Sol Robbins |
| (Carpal Tunnel) |
| 02/17/09 04:25 PM |
| Attachment |
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Re: Contrast Enhanced Diagonal
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Using all my diagonals for the 3 way comparison on Venus showed the CED2 was the clear winner.
Here's a sketch made Last night using the CED1 for Saturn. The Type 1 version was the clear winner for Saturn showing detail better than either a regular diagonal or the too dark CED2.
I hope you find it interesting.