Homemade Hyperbolic Astrograph - 2, Test Jig.

[Chanlunlun]

Dear Star Shooters,

The test jig of the astrograph has been finished. The aim is to test the dimension prior the construction of the metal OTA. Once metal work has been commenced it is very difficult to correct any design error due to wrong dimensional layout.

Another aim is to test run the optic of the whole design. At the moment a 4 inch f/3.5 parabolic mirror is fitted into the jig. Pictures with and without MPCC were shot using the jig and picture qualities were evaluated to see how good the MPCC could improve the picture quality of this particular f/3.5 parabolic mirror.

Attached please see the results . They are quite interesting.

Best regards
Chan Yuk Lun
1 July 2010.

[Chanlunlun]

The quailty of picture at central region - Parabolic mirror alone gioves very sharp image at central region, that with MPCC added gives slightly reduced resolution.

[Chanlunlun]

Now AB compare the lower left corner of the picture with and without MPCC. The standalone parabolic mirror produces terrible coma while the MOCC does its job amazingly.

[Eddy So]

謝謝分享！ [跪拜禮]

[梅西爾]

鏡神，你是否打算專利用這鏡去觀看彗星(因為先前聽鏡神說採用折射鏡可減低彗形像差 )？

[Chanlunlun]

鏡神，你是否打算專利用這鏡去觀看彗星(因為先前聽鏡神說採用折射鏡可減低彗形像差 )？

Dear Messier,

This astrograph is specially made to shoot deep sky objects. It has very fast speed ( f/3.5).

Of course the equipment could also be used for comet shooting.

Best regards
chan Yuk Lun

[PTS]

鏡神，你是否打算專利用這鏡去觀看彗星(因為先前聽鏡神說採用折射鏡可減低彗形像差 )？

I believe you misunderstood the terms.

減低彗形像差 does not mean "minimizing the aberration of the comet". and makes it a good telescope for comet observation.
彗形像差 = coma, which makes a star looks like a comet.

Of course, if you can 減低彗形像差, the image will be very good for all types of observations.

PTS

[梅西爾]

Thanks Mr Chanlunlun and Mr PTS s' teaching.

[starstar]

好型啊！！
真系好型啊！！

[BossKwan]

To Chanlunlun,

So classical your astrograph with this wooden frame!
And the modern focuser seems too deluxe with it...