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| Summer Milky Way Cygnus constellation Simple tripod photo - Canon 40D ISO 1200 |
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| Summer Milky Way Cygnus constellation Simple tripod photo - Canon 40D ISO 1200 |
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Astrophotography from Brooklyn, New York City. I capture the Moon, planets, Sun, Milky Way, and night sky from NYC and during travel. Passionate about astronomy, nightscape, and starscape photography. Using Celestron NexStar 4SE, Coronado SolarMax II 60, Canon EOS Ra, 60Da, 40D, NexImage, and Canon EF lenses to reveal the beauty of the universe.
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| Bahtinov Focus Mask, Celestron NexStar 4SE, Canon 40D, Spica Out of focus - the central spike is noticeably displaced from the |
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| Saturn, Celestron NexStar 4SE, NexImage, Vibration Suppression Pads, Bahtinov mask, Astrophotography |
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| Saturn, Celestron NexStar 4SE, NexImage, Astrophotography |
| Bahtinov mask, Celestron 4SE, Brooklyn Astrophotography |
| Celestron Vibration Suppression Pads |
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| Saturn photos with UV/Infrared Cutoff Filter and without filter, Celestron 4SE, NexImage |
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| Registax 6, Celestron 4SE, Jupiter |
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| Registax 5, Celestron 4SE, Jupiter |
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| Saturn opposition 2011 - Celestron 4SE |
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| Webcam Astrophotography - Celestron 4SE NexImage - Brooklyn Astronomy |
| NexImage and Celestron 4SE- Brooklyn Astrophotography |
| Brooklyn Astronomy and Astrophotography - Celestron 4SE and Celestron NexImage |
| NYC Astrophotography - Celestron 4SE and NexImage |
This post is the first part of a small series showing how to connect a Canon EOS DSLR to the Celestron NexStar 4SE for prime-focus astrophotography. Before assembling anything, here are the individual components you need: the T-Adapter-C90, Barlow T-Adapter 1¼ inches, a Canon EOS T-ring, and the Canon EOS 40D camera body.
Photographing the parts separately helps beginners understand how each piece looks and where it will eventually fit in the optical path. Later posts in this series will show the full assembly and the final connection to the telescope.
| T-Adapter-C90, Barlow T-Adapter 1 1/4 inches, T-ring for Canon EOS, Canon 40D - Astrophotograpgy adapter setup for Celestron 4SE |
This post only shows the individual pieces. In the next steps, you will see how these parts combine into a full optical train for prime-focus imaging or higher-magnification setups using the 1¼-inch Barlow T-Adapter. By understanding the components first, it becomes much easier to follow the later assembly photos and the final telescope-to-camera configuration.
This post shows the second assembled configuration for attaching a Canon EOS DSLR to the Celestron NexStar 4SE. In this setup, the camera is mounted using the 1¼-inch Barlow T-Adapter (93640), providing additional magnification while still operating in true prime-focus mode.
This configuration follows the first assembled setup using the T-Adapter-C90 on the rear port. While both deliver native prime focus, the camera is attached to a different optical output port of the telescope.
| Second assembled configuration: 4SE with Barlow T-Adapter 1¼", Canon EOS T-ring, and Canon EOS 40D on the top optical port |
In the first assembled setup (Part 2), the camera attaches to the rear threaded photographic adapter. In this second configuration, the camera attaches to the top diagonal barrel, the same position normally used by the finderscope bracket.
Both positions are true prime focus, only using different light output paths.
The Celestron NexStar 4SE includes a built-in Flip Mirror Control that allows light to exit through either:
Switching the flip mirror determines which port receives the light. This second assembled configuration simply uses the top port + 1¼-inch Barlow T-Adapter for increased magnification and easier access to the camera screen.
This post shows the third assembled configuration for attaching a Canon EOS DSLR to the Celestron NexStar 4SE. In this setup, the camera connects to the rear port of the telescope, but instead of attaching the DSLR directly, this configuration uses an Erect Image Diagonal (94116) between the telescope and the 1¼-inch Barlow T-Adapter.
This places the DSLR in a horizontal orientation, which becomes especially convenient when the telescope is pointed around 45° above the horizon. Even as the optical tube tilts upward, the camera remains easy to reach, focus, and frame. Although the diagonal changes the direction of the camera, the configuration still operates in true prime-focus mode.
| Celestron NexStar 4SE with Erect Image Diagonal (94116), Barlow T-Adapter 1¼", and Canon EOS 40D. |
The Erect Image Diagonal attaches to the rear threaded port, and the 1¼-inch Barlow T-Adapter is inserted into the diagonal’s eyepiece holder. The Canon EOS T-ring and 40D DSLR attach to the Barlow adapter.
This provides a comfortable horizontal camera position, ideal when the telescope is pointed toward objects at mid-altitude angles (~45° above the horizon). Because the telescope’s native focal path is preserved, this remains true prime-focus astrophotography.
This setup is especially effective when photographing targets located around 45° above the horizon. At these angles, the telescope tube is tilted upward while the DSLR remains horizontal, making focusing and framing much easier.
All three assembled configurations in this series have their own advantages and limitations. Depending on the altitude angle of your target — low, mid-altitude, or near zenith — you can select the configuration that offers the most comfortable and stable camera position.
| Configuration | Camera Port Used | Camera Orientation | Best For (Altitude Angle) | Advantages |
|
Part 2 – Straight Rear Port T-Adapter-C90 + Canon EOS |
Rear Threaded Photographic Adapter | Inline with telescope tube |
Low altitude (near horizon) Best mechanical stability. |
• Shortest optical path • Strong support • Best for Moon, planets, low-angle objects |
|
Part 3 – Top Port via Flip Mirror Barlow T-Adapter 1¼" + Canon EOS |
Top Diagonal Barrel (Flip Mirror Output) | Camera facing upward |
High altitude (70–90°) Ideal near zenith. |
• Very easy LCD viewing • Weight close to mount arm • Excellent for objects high in the sky |
|
Part 4 – Rear Port + Erect Image Diagonal Diagonal → Barlow → Canon EOS |
Rear Threaded Port → Diagonal | DSLR horizontal via diagonal |
Mid-altitude (~45°) Most comfortable orientation. |
• Camera stays horizontal • Very ergonomic focusing • Great for clusters and mid-altitude targets |
Each configuration has its own strengths, limitations, and ideal angle ranges. By choosing the correct setup based on the altitude of your astrophotography target, you can achieve the most comfortable camera position and the best mechanical stability with the Celestron NexStar 4SE.
How to attach a Canon DSLR to the Celestron NexStar 4SE using the T-Adapter-C90 (93635-A) and a Canon EOS T-Ring — a simple and reliable setup for beginner astrophotography.
The Celestron NexStar 4SE is one of the most popular beginner telescopes for planetary, lunar, solar, and bright nebula photography, making it an excellent first step into real astrophotography. This post shows the exact setup I used to attach my Canon EOS 40D DSLR to the NexStar 4SE using the T-Adapter-C90 (93635-A) and a Canon EOS T-ring. If you’re just beginning telescope astrophotography, this is the first and most important connection you need to learn.
The process is simple: the telescope's visual back accepts the T-Adapter-C90, and the Canon EOS T-ring attaches to the adapter. Once the T-ring is locked onto your DSLR, the entire camera becomes the “eyepiece,” letting you capture the Moon, planets, and bright star fields directly through the optical system.
| Canon EOS 40D attached to Celestron NexStar 4SE using the T-Adapter-C90 (93635-A) and Canon EOS T-ring |
This is the complete physical connection: Telescope → T-Adapter → Canon T-Ring → DSLR. No eyepiece is used during prime-focus astrophotography.
This configuration enables prime focus astrophotography, where the telescope’s optics act as the camera’s lens. By attaching the Canon EOS 40D directly to the Celestron NexStar 4SE using the T-Adapter and T-Ring, you get a stable, optically efficient setup ideal for bright astronomical targets.
This setup is perfect for photographing objects such as:
More advanced astrophotographers can later use the NexStar 4SE for certain deep-sky projects with skill and practice, so this telescope can grow with you as you learn. But for beginners, its strongest and most exciting results come from planetary and lunar photography, where the 4SE delivers sharp, detailed images right from the start.
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| Blue Sunset Costa Rica |
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| Sunset Costa Rica |
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| Cloudy Sunset Costa Rica |
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| Gold Sunset - Costa Rica |
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| Total Lunar Eclipse Celestron NexStar 4SE Canon 40D |
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| NYC Total Lunar Eclipse Celestron 4SE Canon_40D Brooklyn Astronomy |
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| Total Lunar Eclipse Celestron 4SE Canon_40D Brooklyn Astronomy |
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| Total Lunar Eclipse Celestron 4SE Canon_40D Brooklyn Astronomy |
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| Total Lunar Eclipse Celestron 4SE Canon_40D Brooklyn Astronomy |
This Blue Moon from November 21, 2010 was photographed in Brooklyn using a Canon 40D and Celestron NexStar 4SE telescope, showing how different white balance settings reveal natural lunar colors.
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| Color full moon, blue moon, Canon 40D, Celestron 4SE |
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| Blue Moon Celestron 4SE Canon 40D Brooklyn Astronomy |
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| Full Moon Celestron 4SE Canon 40D Brooklyn Astronomy |
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| Full Moon Celestron 4SE Canon 40D |
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| Celestron 4SE Canon 40D Moon Brooklyn Astronomy Backyard Astrophotography |
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| Apollo 15 landing site at Hadley–Apennine region, Mare Serenitatis, Mare Tranquillitatis. Canon 40D, Celestron 4SE, Brooklyn Moon astronomy from backyard |
| Tycho crater, Brooklyn Moon astronomy from backyard Canon 40D and Celestron 4SE |
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| Moon astrophotography Canon 40D and Celestron 4SE, Tycho crater, Brooklyn Moon astronomy from backyard |
| Copernicus crater, Astronomy from Brooklyn backyard Canon 40D and Celestron 4SE |
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| Celestron 4SE Moon Copernicus crater, Brooklyn backyard Astronomy |
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| Moon Celestron 4SE Canon 40D Astronomy Brooklyn Astrophotography |
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| Comet Hartley 2, Celestron 4SE Canon 40D Brooklyn |
| Brooklyn Astrophotography, Celestron 4SE PiggyBack, NYC Astronomy |
| PiggyBack Camera Mount for Celestron NexStar 4SE (Item# BRKTPIG4), Comet Photo Setup, Brooklyn NYC Astrophotography |
| NYC Astrophotography, Celestron 4SE |
| Celestron 4SE and Canon 40D - NYC Astrophotography |