天文观察摄影雜记---林月笙香港天文台

ＬＳ的是不是没对好焦呀．．．．．．．．．

ＬＳ的是不是没对好焦呀．．．．．．．．．
zhangke_ss 发表于 2011-8-1 23:57

                               
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这个我当时调到没法再调了,调焦座没有微调(1:12) 扭制就是有那样不便。
另外作晚处理图像时，家里那台电脑看和现在公司这台电脑看明显差别好大，这台看起来要暗好多，好像细节都没了那样。
今早一到公司打开一看，唉马上没劲了。。。
我不知道你那台电脑看得怎样，一般要有图象卡的电脑才好看。

US ASTRONOMY


ghswen : Yesterday, 04:01 PM from Murrieta, CA

You're getting close to 30 MANDII!
Keep at it.



laney50w : Yesterday, 04:03 PM from New York
Hey Mandii,

Nice picture! Keep up the good work!
Chris




Uncle Peter : Yesterday, 10:08 PM from Toronto, Ontario, Canada
Nice photo Mandii. Was that taken using a CCD camera?


deaman49 : Yesterday, 11:19 PM from Allegany, New York
Nice Pic Mandii!


MANDII : Today, 01:20 AM
Dear Uncle Peter ,

Yes , It's the one Meade DSI with color version . It has version I , II and III , and my one is version one . I had used it for nearly one and half years , so far no complaint on it's price and it's performance .


And also , betting clear skies and thanks all of you above having kind touch here .



CLOUDY NIGHTS

UmaDog : 08/01/11 09:45 PM from Long Island, NY

Nice, thanks. I know the feeling about clouds. If conditions are bad for long periods of time then it's hard to be motivated. I didn't realise Hong Kong was so cloudy.


MANDII : 08/01/11 09:45 PM
Well I don't mind what you had said the M93 to me previosuly , besides you had encouraged me a lot indeed ,to keep in mind not being lazy and keep on doing it .

Thank you sir from Long Island .

US ASTRONOMY

MANDII : Yesterday, 11:04 AM

Gordon this is the summary list with report number for easier check on each objects . Actually originally it's placed in first post of this thread and should be updated everytime ,but I can't update it anymore after some time it's posted . So I would like to have this summary list here now .



Uncle Peter: Yesterday, 08:32 PM from Toronto, Ontario, Canada
Mandii, that is the CCD camera I am planning to buy! I wasn't sure about how the images would be with the DSI, but now I see that they'll be just fine, judging from your photos.



MANDII : Yesterday, 09:58 PM
Wow uncle Peter don't do that , or It may waste you some unneccessary money ... It may not be a good choice for you actually . I am just saying my own favour ONLY. Besides I am not an experienced person ,especially in the field of equipments . You see I didn't use too much different equipments before ,so I don't know much about the equipments actually . I am only a person who try to use the most on what I have on hand .

For which CCD device is better , it's better you ask for advice from those experience persons in the CCD equipment sub forunms . They are much experienced than me .



Uncle Peter : Today, 01:27 AM from Toronto, Ontario, Canada
Thanks for the heads-up Mandii. I know for sure I don't want to get an expensive CCD camera. Some of them are as much as $1000 and more. I will head over to the CCD imaging forum and ask them if the Meade DSI is a good model to buy.

The exact model is the Meade DSI II Pro.

NO.27 )

Tonight M15 , little cloud , but transparancy worser than previous observing night .
I can't see the comic near M15 in eyepiece (K25mm) , though I had searched it for long time around the region of M15 . The DSI even much more smaller picture-FOV ( at least 4 times smaller ) than the eyepiece , thus it surely cannot cover this comic in picture . Anyway , this is the result of observing , tonight .


ORION 6"/F5 Newtonian
EQ3 unguide
DSI-I ( 30s X 16)
IRIS

Observe : 2011/08/03 10:00p.m

CLOUDY NIGHTS

UmaDog : 08/03/11 10:59 PM from Long Island, NY

Thanks for posting! I like M15. I spent some time trying to see the planetary in it on Saturday. I think I found the location but couldn't confirm it.

Do you ever get the chance to make trips to darker skies?




MANDII : 08/03/11 11:50 PM

well sir bascily I am a lazy man . I am lazy going out and no such time as well after work everyday .
I don't want to bring things . It's probably not the reason of distance , let say even I just need to setup the telescope every time observation on my home platform , just on my platform , and evreytime bring back these equipments after complete the observation . " That would also be a diffculty for me " . So you can understand now how it is impossible for me to go out . And that's the main reason I setup an observatory . Also , I want frequent observation , not talking about seldom use my teslecope , so frequent that I observe so many things like the Moon ,the planets and even the Plants on the nearby hill as well . Not only the DSO . So how can I setup the telescope every time if it's needed so frequently ?? That's impossible without an observatory that already setup and keep everything
well for you in a outside place .

2ndly , my location is quite dark already in Hong Kong , though it's not very dark but still OK . If the outside dark area is clear that night , then my place is just same . For me , The main problem is not the darkness in my site , it's the weather of cloudy nights and the quality of sky . I mean the Dust and thin misky layers that always covers the whole sky and make the tarnsparancy very low . And this is geographic weather matter , basicly everywhere in Hong Kong is just same . Not so many nights in a year without the clouds , not so many nights has very sharp stars . No matter where you go in a such small place in Hong Kong , the sky is just same . Cloudy and unclear nights . That's why I come this cloudy night forunm now .

US ASTRONOMY


WWPierre : 08-07-2011, 02:38 PM from Squamish B.C.

I set myself the task of finding the comet C/2009 P1 (Garradd) without the help of go-to.

I chose my new Vixen ED80, and set it on the motorized EQ3-2. with my Siebert 30mm ultra in the focuser. I started at ENIF (Epsilon Pegasus) and hopped to M15. Then I downloaded the PDF of the comet's path, and related it to Stellarium. I don't have the comet in the Stellarium data base, because I haven't been able to get any of the newer versions of Stellarium to run on this computer. There are a lot fewer stars in the PDF than Stellarium, so it took me a while to estimate the position of the comet. Once I determined it to be close to a certain keystone shaped asterism, I caught it with averted vision. When I was certain there was actually something there, I checked Stellarium, and determined that what I saw wasn't in the program.

The motor drive on the EQ3-2 is not equipped with a clutch, so it became a PITA to star hop, as the fastest slew it can muster is 8Xsiderial, which is pretty slow. I made sure I had a good balance, and loosened both clutches, that way I could move the scope on the EQ mount just as conveniently as if it were a dob, with the added advantage of tracking after target acquision and re-clamping.





MANDII : Today, 05:25 PM

Well Pierre your this article make me feel excited very much now . I also did try to find it out on last wednesday when it's very near M15 . People say it's near M15 . I use 6"/ F5 with 25mm eyepiece I can find out the M15 ! A white misky thing in an eyepiece indeed . Very nice ! Teh nI try to move around my telescope in search the comet , within 2 to 6 degree of FOV range . But I just can't see it ! Well I guess may be the sky transparency is not so good . So finally I just take a picture of the M15 . And ends up such a wonderful observing night , I still say it's wonderful though I have no chance to have a look on the real face of this comet , but you know the M15 had make me happy .

Clear skies for this simple report to evrybody , who are getting crazy with thuis comet recently .

中国牧夫

今日起撤退中国牧夫论坛 ！

爱牧夫技术：2011-9-16 14:11:42
论坛升级的工作即将开始，会有一段时间，导致无法访问，敬请谅解！



MANDII：2011-9-17 09:05:44
靠！怎么以前每个版面里的热门主题小窗口都没了，至顶的贴又保留，那么不公平！
那以后进论坛还有啥意思，以后都不来！

一年没来牧夫,这张贴的记录未完过，只是记在国外的论坛里，今日想继续这张未完的贴。
这一年以来，器材一样，有空便拍拍玩玩，好天就那么几天一年里,拍一个深空便算一个,还得补上一些这一年里的照片。




NO.28)

木星: 2010/10/11_No.12 | 2010/10/12_No.13 |2010/10/13_NO.14|2011/09/27_NO.28


ORION 6"/F5 Newtonian
EQ3
2X Barlow
DSI-I ( 0.0387s X 735)
Meade Envisage Drizzle Box stacking , Registax .

Observe : 2011/09/27 11:15 p.m

No.29)

补倆张M42和M45漏记照片。那时家里有部老爷机Olympus C-40 Digital camera  , 目镜（K25mm)后拍摄，暴光只能16秒，10张叠加。
这倆个M天体很亮，此DC机够感光，这倆张照片算是我比较满意的，当时给了我很大稀望，以为找到了现成的机子，可以不费一分钱又能达到个人拍M天体的目的。
想一直用它来拍，我是想拍比较亮的M天体，星团类为主，后来很失望在接下来倆三次中拍不到其它的星团，连M6，M7都不行。感光不够没它办法。
所以后来只能继续用DSI，DSI 是三年前决定用的，是我现有相机中感光最高的一部了，一直以来也没打算更新器材。

Orion 6"/F5 newtonian
K25mm eyepiece
EQ3
Olympus C-40Zoom (16s X10 )
IRIS , Photoshop

Observe :2011/12/27

NO.30)

Tonight very excited . The sky suddenly become a bit clear without not much clouds at around 10 o'clock . So I quickly take action . I spend around 30 minutes to find out this M41 by myself , I am very pleased when I see it . It's really beautiful in the eyepiece , so many bright stars ! And then after looking it for a while I turn to do imaging . At first I use my Omlympus Digital camera since last time it can have enough sensitivity on M45 and M42 , but this time M41 is much dimmer . It cannot be shown even a little bit of this M41 on the camera display at it's maximun 16 seconds exspoure . And then No way so I have to change to use DSI , so fianlly I can catch it at 15 seconds per frame in DSI , I take 22 frames . Finally do stacking in IRIS , and finalize in PS . Tonight the observing session is fine . The time now is 0:46am.

NO.31)

Olympus DC : 16s X 21
IRIS , PS .



So tonight this M35 is not really a good take , but it's just better than nothing .
Because I can have one more object in my list .
The tracking is very bad . My main goal this time is to see if my DC can have enough sensitivity to this cluster with magitude 5.0 under this low transparancy sky . It still can show a bit of this M35 . I realise the reason why last time the M41 was not captured well by my DC , it's not because of the DC sensitivity. It was because I haven't switch on the noice reduction option of my DC , that's why it produced so much noise and cannot revealed the object well .
2ndly , tonight M35 is located nearly at the zenith region , It's my first time to shift backward the observatory dome to do shooting . I found it's not very difficlut for me to rasie it up and move it back . So I am pleased about it .
                                                                                                                                                                                                                                                                                                                                                                               

No.32)

It's 1 months no clear nights , tonight I shoot M50 ( mag= 5.9 ,size =15').
it's taken with DSI , 30 seconds X 17 .
I use a dirfting softwere (WCS for DSI ) to do polar alignment .
Stacked in IRIS , post process in PS ( curve function , treshold ).

No.33)

Tonight M3 .
15 seconds x 35 taken by DSI
stacked in IRIS , PS pro-processed

NO.34)

作晚木星

ORION 6"/F5 newtonian
2X barlow  
EQ3
DSI ( 303 frames)
IRIS , PS

Observe : 2012/10/19  22:15

NO.35)

M34 今晚,人肉时角定位，星体与目镜中心偏差约1/3度，单张15秒55张,总跟踪时间850秒单跟,首次使用DSI双星自动叠加，PS后期。

ORION 6"/F5 Newtonian
EQ3
DSI（ 15s X 55)
Photoshop

Observe : 2012/10/25 22:00

分开单独发贴

http://www.astronomy.com.cn/bbs/thread-245415-1-1.html
http://www.astronomy.com.cn/bbs/thread-245415-1-1.html

No.36)


作晚木星,试下用philips spnc700 nc 摄像头,同样也是加2X , 比上次DSI 拍的大是大点,但没那么清楚。

ORION 6"/F5 Newtonian
EQ3
2X barlow
Philipes spn700nc （ 500 frames )
IRIS , Photoshop
Observe : 2012/10/31 22:30

分贴:
http://www.astronomy.com.cn/bbs/thread-245648-1-1.html

这里我发现有一个很重要的线索，一直以来不是很明白的疑团。
比较一下NO.34和No.36倆个木星,同样的镜子和巴罗为何会不一样大小,刚刚看了下倆部相机的感光片大小,
philipes摄像头比DSI要小点,大小比例和照片上用尺量下看起来差不多的,说明感光片越小,拍出来就越大。
这跟视场肯定有关系，这正正解释了为什么用DSI拍出来的星点要比单反的要大许多了，就算跟踪和对焦准确。
DSI的感光片面积可能是单反的十倍小! 同样的条件下星点就大十倍了。

不过如果我改用单反会有个问题得很小心考虑，因为没有GOTO， 无法确定星体位置，我是用目镜来确定位置的，用DSI可以很方便很快速地在目镜与它之间更换，目镜里找到后便插上DSI拍照，很容易，而且DSI又轻不会那么容易使整部镜子跑位。但单反估计可没那么容易和目镜对换，因为接口那里要上紧的。加上单反很重镜子没法很紧贴目标。所以一般人家用单反都是用GOTO，那样就不用目镜而星体位置能确定。星体位置不确定，目镜里可以立即看立即找，而相机便得暴光一定时间才行，那样找起来很费时间，不太可能那样做。所以用单反必需要有GOTO !

DSI就是星点太大了，没有单反那种幼细，加上单反视场大十倍，整张照片便布满星点了，看起来很自然地就变得漂亮多。而DSI的就显得单调，就那么几颗星 点，暗的又非常的暗没法解像得到。就是视场小，没它办法。视场小如果能解像到非常暗的星点倒没什么，那样整张照片依然还有很多的星点，那也很好看。但是相 机感光力就要更强的才可以了，就很贵的相机了。