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There are two sunspots and one of those with a scar. Isn’t it funny? The seeing today is bad. Originally I intended to use TV 5X & DMK 21 to do a high magnification shot, but it sucks because of the bad seeing today. These images are taken with TV 2.5X & DMK21.

LS80T, TV 2.5X, DMK21

Nice pictures willis, today's sun is fun.

I shared this experience with my mother today and she was pretty surprised by the nature of sun.
My mom said that binoviewer with WO's 20mm is much better than Baader zoom's 20mm and significantly better than single eye observation.

I'm really confused...because I still believe Baader's obtain a better image than WO's (WO's is fairly well actually), however using Baader's Zoom are hard to reach focus and complicated to make any adjustment for laymen. If I want to share the sun with the others in the coming days, it means I must keep the WO's pair.

StevenTam 寫:Nice pictures willis, today's sun is fun.

I shared this experience with my mother today and she was pretty surprised by the nature of sun.
My mom said that binoviewer with WO's 20mm is much better than Baader zoom's 20mm and significantly better than single eye observation.

I'm really confused...because I still believe Baader's obtain a better image than WO's (WO's is fairly well actually), however using Baader's Zoom are hard to reach focus and complicated to make any adjustment for laymen. If I want to share the sun with the others in the coming days, it means I must keep the WO's pair.

May be the binoviewer experience is TOO comfortable that she thinks she sees more. Also, most people do not scrutinize the details of the sun like you do when testing which eyepiece is better. They just take the overall view and give a comment on the general impression.

Usually, I show the single-eye view to people first, then the binoviewer. This is because binoviewer is harder to adjust for laymen, and people usually view the image for MUCH LONGER on binoviewer.

對，我試過有一次在路邊天文用上Mark V雙目，但因為要因人而異慢慢調，發現是反效果，不用用一個Ethos 17看月亮好了。

Televue Radian 是很好的行星目鏡，eye relief也夠長，若當晚精神狀態不好，眼睛有點累，你會發現很容易用它看出比TMB Supermonocentric多的東西。所以比較目視裝置的終極解像度對比度時，眼睛狀況要夠好才成，一般沒經驗的人很容易把舒適度評價為器材的目視性能。

正如一輛跑車，用薄闊的輪呔及換上硬避震是指定動作，但乘客絶不舒服。

P.S.，Willis第一張照片中，那兩顆黑子附近的結構，我昨天搞活動時，用LS35T也看到，很美的。

社長 寫:P.S.，Willis第一張照片中，那兩顆黑子附近的結構，我昨天搞活動時，用LS35T也看到，很美的。

Yes! I always use both LS80T & LS35T to do observations. I found that the image of LS35T is brighter than that of LS80T. The proms viewed under LS35T is brigther. However, the details of both proms & suface are much better under LS80T. I guess it is due to the band width of LS80T is narrower.

willis 寫:

社長 寫:P.S.，Willis第一張照片中，那兩顆黑子附近的結構，我昨天搞活動時，用LS35T也看到，很美的。

Yes! I always use both LS80T & LS35T to do observations. I found that the image of LS35T is brighter than that of LS80T. The proms viewed under LS35T is brigther. However, the details of both proms & suface are much better under LS80T. I guess it is due to the band width of LS80T is narrower.

No, LS35T 是設計成透光率較高，以容許較高放大倍率觀測的(20-60x)，跟頻寛無關。

社長 寫:

willis 寫:

社長 寫:P.S.，Willis第一張照片中，那兩顆黑子附近的結構，我昨天搞活動時，用LS35T也看到，很美的。

Yes! I always use both LS80T & LS35T to do observations. I found that the image of LS35T is brighter than that of LS80T. The proms viewed under LS35T is brigther. However, the details of both proms & suface are much better under LS80T. I guess it is due to the band width of LS80T is narrower.

No, LS35T 是設計成透光率較高，以容許較高放大倍率觀測的(20-60x)，跟頻寛無關。

So Lunt should use the same technology in LS80T!

David & 社長, Thank you for your sharing.

I also believe eye-relief is improtat to observation but a pair of good quality eye piece with long eye-relief is certainly not cheap. Anyway, the lunt zoom eye piece is just fairly perform on sun, I am wondering when Mr. Lunt will announce his new series. Any news or hearsay information on that?

StevenTam 寫:David & 社長, Thank you for your sharing.

I also believe eye-relief is improtat to observation but a pair of good quality eye piece with long eye-relief is certainly not cheap. Anyway, the lunt zoom eye piece is just fairly perform on sun, I am wondering when Mr. Lunt will announce his new series. Any news or hearsay information on that?

有一段時間用過Radian, Panoptics，開始對eye relief的感覺不大。

例如Pentax XO目鏡的eye relief特別短，但我很深知觀測行星月面的確要聚精滙神的。

那次我們在石澳用Baader Mark V雙目配兩個Ethos 13，其實eye relief也不算長，但一看M42就好像整個頭伸入太空一樣。

很多人說TMB Supermonocentric的eye relief短，但忘了那是30度視場的目鏡，實際上寛容度大一些的，所以David第一次試用TMB Supermonocentric時，他是一面問這類目鏡eye relief會否很短，一面忘了自己是戴著眼鏡看mon 4的，然後他明白了。