Seibert Eyepieces



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Date: NA
Price: $40.00+
Design: Various designs
Description: 1.25 inch eyepieces.


Iíve been into astronomy for 30+ years now and have seen and used a good many different eyepieces. Being primarily a planetary observer in my early years, I used only Orthos. I remember the eyepiece that I would use all the time on the 12 Ĺ" f/10 scope, would be the Meade 12.5mm Ortho. Saturn would look great through this eyepiece. A few years later, University Optics (UO) Orthos caught my attention, so I bought a set and have used them since. These UO Orthos were the best going eyepieces and were hard to beat. Even when using Zeiss Orthos, I would  always revert back to the University Optics Orthos. So it just goes to show that you do not have to spend an astronomical amount of money to get great eyepieces.

When it comes to the planets, Orthos are definitely the way to go (or so I thought)  for sharpness contrast and brightness. The only thing I was looking for in eyepieces when observing the planets was good eye relief. Well, I finely found the eyepieces that give the eye relief, brightness, sharpness and the contrast. These eyepieces are made by Siebert Optical. Not only is the owner Harry a joy to do business with ( which is hard to find today ) but you can personally talk with the designer about the eyepieces that he makes.

After asking Mr. Siebert which eyepieces he would recommend for observing this coming Mars opposition, he recommends his 7mm, 10mm, 12.5mm to be used with my 6" f/8 refractor. Iíve read some good reviews on his 10mm eyepiece being used on M42 with great results and the same with his 12.5mm, so knew I would be able to use these for my deep sky observing also. Well, enough about all of this, and onto my results of the testing that I did with these eyepieces.

My testing began with the 12.5mm Siebert against the Meade 12.5mm Ortho, UO 12.5mm Ortho and a Meade 12.5mm Plossl. The eye relief  of the Siebert was more comfortable to view through than either of the Meade eyepieces and the UO Ortho. I began testing the eyepiece for coma near the edge of the eyepiece. This was a main concern I had after reading that this was a minor problem with the Siebert in fast scopes. In my f/8 refractor stars were pin points all the way across the whole field of view with no coma seen at all. With the Meade Plossl there was coma near the last 10% of the field of view, while there was no coma at all in the Meade or UO 12.5mm Orthos. As for sky blackness, the Siebert was the best. I then moved onto Jupiter to compare sharpness and contrast among the four 12.5mm eyepieces. At 384x with the help of a 4x TV POWERMATE, the Plossl was in the back seat compared to the two Orthos and the Siebert 12.5mm eyepiece. The Siebert was sharper and was a good deal brighter than the Meade Ortho and was running head to head with the UO Ortho. In brightness the Siebert out did the Meade Plossl and was a tad bit brighter than the UO Ortho. The Siebert beat the Plossl in contrast and had just a tad bit more contrast than the UO Ortho and the Meade Ortho (the difference was slight but noticeable among the three). I find myself using this Siebert 12.5mm eyepiece a lot for globular clusters in my 9 1/4" SCT also.

The Siebert  15mm eyepiece ( that I got for deep sky observing )  is everything that the 12.5mm is, but with a slight ghosting on Jupiter. It is brighter than the Meade 4000 series 15mm SP and the sky is much blacker also. When compared to the Zeiss 15mm Ortho on Jupiter, the only problem it has is the ghosting like I said earlier. As far as brightness goes it is equal to the Zeiss Ortho, but because of the ghosting it loses out on sharpness and contrast. Where the Siebert 15mm excels, is on deep sky objects. When observing open clusters with the 15mm Siebert and the 15mm SP Meade, the Siebert is sharper and with no coma at all across the whole field of view. The Meade had no coma also, but where the Siebert beats the Meade is in the blackness of the sky which makes the stars sharper.

My two new favorite Lunar and  planetary eyepieces are the Siebert 7mm and 10mm wide angles. All I can say is that the 7mm is great. It is very sharp and shows a lot of sharpness on Jupiter and Saturn. Contrast is a must see to appreciate kind of thing with this eyepiece, with a lot of detail being seen easily. I compared this eyepiece against one of the greatest planetary eyepieces out there, which is the one and only University Optics 9mm Ortho. Boy was it a fight to the end, no way did I ever think that this would be the best duel going for me during this comparison. I thought for sure when it came to these two eyepieces that the University Optics would walk all over the Siebert in contrast and sharpness. (I was only thinking this because Iíve compared the UO 9mm Ortho to a good many high-priced eyepieces and it always won) Well, it now had an eyepiece that not only ran neck in neck with it in the contrast arena but also in sharpness and brightness. When it was all done and over, the Siebert made me a believer that there was an eyepiece out there that could do it.

The end result showed that the Siebert 7mm Wide Angle was as sharp and had as much contrast as the old University Optic 7mm Ortho did. Siebert Optics just edged out the UO in brightness, and the background sky was blacker in the Siebert 7mm Wide Angle than in the UO 7mm Ortho. The Siebert 7mm has a 65 degree field of view compared to 45 degree field of view for the UO Ortho. The same results were to be had with the Siebert 10mm comparison, with the only difference being in brightness. University Optics 9mm Ortho was a bit brighter between the two eyepieces.

I highly recommend the Siebert 7mm, 10mm, and 12.5mm for planetary observing and the 15mm for bright nebulas and tight open clusters. With the 4x TV POWERMATE the 15mm is a good globular cluster eyepiece when the seeing allows that kind of power to be used. I used the combo of the 4x POWERMATE and the 15mm in my 6" f/8 Refractor on M13, what a sight it was, totally resolved right to the core with dark lanes running through the cluster.

Iíve read so many reviews where people say that in the looks department the Siebertís wont win any contestís, but I must say that this is not all that true. These are nice looking eyepieces and very well built with a good solid feel. They are very light weight which is good as far as Iím concerned. The other thing that gets me is when reviewers write things like, these are nice sharp eyepieces for the money.

Come on now, these are great eyepieces even if they were $200 instead of $40 to $45. You do not hear this kind of comment about the University Optics Orthoís which sell at $55 to $65, and these are great eyepieces which have stood the test of time. Mr. Siebert is doing use all a favor by making a good line of eyepieces at a very good price, keep up the good work Harry. I own the whole line of Meade 4000's and all the University Orthos, the whole line of Vixen LV eyepieces and now Iíll be owning all the Siebertís.

Review by Don Regan, Director of the Deep Sky Observatory, and also new Director of the Deep Sky Observatoryís planetary section. Main scope is a 12" SCT and two 6" APO refractors and a 9" APO.

Submitted by Don Regan - - New York

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