Adding equipment to the observatory telescope
At this time of year, large nebulae and open clusters are scattered across the sky, but they cannot be captured by the Prime Focus F/8 of the RC10.
Therefore, I decided to mount a short-focus telescope on the RC10 to photograph these nebulae and clusters.
(1) The first challenge of this operation is the guide scope.
Currently, I am using a guide scope with a focal length of 240mm, but if it is shorter than this, it will be difficult to guide the RC10. However, if I put a fixed-focus telescope and a 240mm guide scope on the RC10, the balance will not be good.
Therefore, I decided to guide with the newly purchased Touptek OAG.
This OAG is easy to use because the screw position is compatible with the ZWO EFW.
The main camera is the QHY294C-Pro (MFT).
(2) The second challenge is a filter holder.
Since I will be targeting nebulae and clusters, I need broad band and narrow band filters. Therefore, I decided to use a 2”X5 EFW, even though it would be heavy.
UV/IR, L-eNhance, L-Ultimate, SemoAPO, IR850
(3) The third issue was the telescope.
The RC10 has an electric cover and flat light source, so a long one is not possible.
Also, a large aperture is not possible because there is a risk of hitting the roof.
So I considered three telescopes as candidates from the ones I have.
- RedCat51: Best in terms of performance, but connecting OAG + EFW + manual rotator would easily exceed the 55mm back focus, so it cannot be used.
- TS SD70 Quad: Back focus is fine, but the Image Circle is APS-C, so I was worried about the accuracy of the OAG and rejected it.
- William Optics Z61: A telescope I bought about 5 years ago and have hardly used. It has halos and peripheral coma aberration because it is an APO Doublet, but the image The Circle is full size and there is plenty of room for the OAG. The lens used is the FPL-53, so there is no complaint about the color reproduction. It is used at Prime Focus F/5.9, so there are no problems with the back focus.
Result: The telescope was decided to be the WO Z61.
*The CMOS angle was fixed to a vertical composition. After checking various objects, the vertical composition was found to have an 80% or higher probability of capturing the subject.
今時期大きな星雲や散開星団が空に散らばっているが、RC10のPrime Focus F/8では収まらない。
よって、RC10の上に短焦点の望遠鏡を載せて、それらの星雲星団を撮影することにした。
（１）この作戦の最初の課題はGuideスコープである。
現在焦点距離240mmのGuide鏡を使っているが、これより短いとRC10のGuideは厳しい。しかし単焦点の望遠鏡と240mmのGuide鏡をRC10に積むとバランスが取れない。
よって、新規に購入のTouptek OAGでGuideをすることにした。
このOAGはZWOのEFWとスクリューの位置がコンパチブルなので使いやすい。
メインのカメラはQHY294C-Pro(MFT)
（２）2番目課題はフィルターのホルダーである。
星雲と星団をターゲットにするのでBroad BandとNarrow Bandのフィルターが必要。よって重くはなるが2”X5のEFWを使うことに。
UV/IR,L-eNhance,L-Ultimate,SemoAPO,IR850
（３）3番目の課題は望遠鏡である。
RC10にElectric Cover兼Flat光源が付いてるため長いものは無理。
また屋根へぶつかる危険もあるので大きい口径も無理。
よって手持ちの望遠鏡から候補として3つの望遠鏡を検討した。
・RedCat51：性能の的にはBestだが、OAG＋EFW＋手動Rotatorを接続するには55mmのBack Focusを余裕で超えてしまい、利用不可。
・TS SD70 Quad：Back Focusは問題ないが、Image CircleがAPS-CのためOAGの精度に不安を感じて却下。
・William Optics Z61：5年くらい前に買ってほとんど利用していない望遠鏡。APO Doubletのためハローや周辺のコマ収差があるが、Image CircleがFullサイズでOAGも余裕。レンズもFPL-53を利用しているので色の再現力は文句なし。Prime Focus F/5.9で利用するのでBack Focusも問題無い。
結果：望遠鏡はWO Z61に決定。
＊CMOSのアングルは縦構図で固定。色々Objectをチェックした結果縦構図の方が被写体を収められる確率が80%以上あったため。
最後にGuide性能と写り具合のチェックのためにL-Ultimateで撮影した10分露出のSingle Exposurer Rosette Nebula
At this time of year, large nebulae and open clusters are scattered across the sky, but they cannot be captured by the Prime Focus F/8 of the RC10.
Therefore, I decided to mount a short-focus telescope on the RC10 to photograph these nebulae and clusters.
(1) The first challenge of this operation is the guide scope.
Currently, I am using a guide scope with a focal length of 240mm, but if it is shorter than this, it will be difficult to guide the RC10. However, if I put a fixed-focus telescope and a 240mm guide scope on the RC10, the balance will not be good.
Therefore, I decided to guide with the newly purchased Touptek OAG.
This OAG is easy to use because the screw position is compatible with the ZWO EFW.
The main camera is the QHY294C-Pro (MFT).
(2) The second challenge is a filter holder.
Since I will be targeting nebulae and clusters, I need broad band and narrow band filters. Therefore, I decided to use a 2”X5 EFW, even though it would be heavy.
UV/IR, L-eNhance, L-Ultimate, SemoAPO, IR850
(3) The third issue was the telescope.
The RC10 has an electric cover and flat light source, so a long one is not possible.
Also, a large aperture is not possible because there is a risk of hitting the roof.
So I considered three telescopes as candidates from the ones I have.
- RedCat51: Best in terms of performance, but connecting OAG + EFW + manual rotator would easily exceed the 55mm back focus, so it cannot be used.
- TS SD70 Quad: Back focus is fine, but the Image Circle is APS-C, so I was worried about the accuracy of the OAG and rejected it.
- William Optics Z61: A telescope I bought about 5 years ago and have hardly used. It has halos and peripheral coma aberration because it is an APO Doublet, but the image The Circle is full size and there is plenty of room for the OAG. The lens used is the FPL-53, so there is no complaint about the color reproduction. It is used at Prime Focus F/5.9, so there are no problems with the back focus.
Result: The telescope was decided to be the WO Z61.
*The CMOS angle was fixed to a vertical composition. After checking various objects, the vertical composition was found to have an 80% or higher probability of capturing the subject.
Finally, a Single Exposurer Rosette Nebula with a 10-minute exposure taken with the L-Ultimate to check the Guide performance and image quality.
観測所の望遠鏡への機材追加
今時期大きな星雲や散開星団が空に散らばっているが、RC10のPrime Focus F/8では収まらない。
よって、RC10の上に短焦点の望遠鏡を載せて、それらの星雲星団を撮影することにした。
（１）この作戦の最初の課題はGuideスコープである。
現在焦点距離240mmのGuide鏡を使っているが、これより短いとRC10のGuideは厳しい。しかし単焦点の望遠鏡と240mmのGuide鏡をRC10に積むとバランスが取れない。
よって、新規に購入のTouptek OAGでGuideをすることにした。
このOAGはZWOのEFWとスクリューの位置がコンパチブルなので使いやすい。
メインのカメラはQHY294C-Pro(MFT)
（２）2番目課題はフィルターのホルダーである。
星雲と星団をターゲットにするのでBroad BandとNarrow Bandのフィルターが必要。よって重くはなるが2”X5のEFWを使うことに。
UV/IR,L-eNhance,L-Ultimate,SemoAPO,IR850
（３）3番目の課題は望遠鏡である。
RC10にElectric Cover兼Flat光源が付いてるため長いものは無理。
また屋根へぶつかる危険もあるので大きい口径も無理。
よって手持ちの望遠鏡から候補として3つの望遠鏡を検討した。
・RedCat51：性能の的にはBestだが、OAG＋EFW＋手動Rotatorを接続するには55mmのBack Focusを余裕で超えてしまい、利用不可。
・TS SD70 Quad：Back Focusは問題ないが、Image CircleがAPS-CのためOAGの精度に不安を感じて却下。
・William Optics Z61：5年くらい前に買ってほとんど利用していない望遠鏡。APO Doubletのためハローや周辺のコマ収差があるが、Image CircleがFullサイズでOAGも余裕。レンズもFPL-53を利用しているので色の再現力は文句なし。Prime Focus F/5.9で利用するのでBack Focusも問題無い。
結果：望遠鏡はWO Z61に決定。
＊CMOSのアングルは縦構図で固定。色々Objectをチェックした結果縦構図の方が被写体を収められる確率が80%以上あったため。
最後にGuide性能と写り具合のチェックのためにL-Ultimateで撮影した10分露出のSingle Exposurer Rosette Nebula
コメント