{"product_id":"shelyak-se0150","title":"Shelyak Alpy \u0026 UVEX 35 µm slit","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003e35 µm Precision Slit Width\u003c\/li\u003e\n\u003cli\u003eIntegrated Guiding Mirror Surface\u003c\/li\u003e\n\u003cli\u003eCompatible with Shelyak Alpy \u0026amp; UVEX Spectrographs\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eDownloads\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eAlpy \u0026amp; UVEX 35 µm slit\u003c\/h2\u003e\n\u003cp\u003eThe Alpy \u0026amp; UVEX 35 µm slit is a core component for Shelyak spectrographs, functioning as both a precision entrance aperture and a guiding mirror. Its 35 µm width strikes a versatile balance between spectral resolution and light throughput, making it a standard choice for a wide range of astronomical targets.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eThe 35µm Slit: Balancing Resolution and Light Throughput\u003c\/h3\u003e\n\u003cp\u003eIn spectroscopy, the slit width directly controls the trade-off between the detail in your spectrum and its brightness. The 35 µm slit for the Alpy and UVEX spectrographs is a popular choice because it represents a highly effective compromise for many observing conditions and targets.\u003c\/p\u003e\n\u003cp\u003eThe polished, reflective surface surrounding the slit allows you to view the entire star field through your guiding camera. This ensures you can keep your target perfectly centered on the nearly invisible slit for long exposures, maximizing signal and preventing drift.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eSlit Selection for Alpy \u0026amp; UVEX: The 35µm Slit vs. Other Options\u003c\/h3\u003e\n\u003cp\u003eChoosing the correct slit is fundamental to achieving your scientific goals. While the 35µm slit is an excellent all-rounder, understanding its context helps you make the right decision for your specific target.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003evs. Narrower Slits (e.g., 25 µm):\u003c\/strong\u003e A narrower slit yields higher spectral resolution but passes significantly less light. It is the superior choice for studying fine absorption lines in the spectra of bright stars, where signal is plentiful.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003evs. Wider Slits (e.g., 50 µm+):\u003c\/strong\u003e A wider slit captures more photons, which is critical for obtaining a usable signal on very faint objects like distant galaxies or low-surface-brightness nebulae. The trade-off is a lower-resolution spectrum where fine details may be blurred.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eThe 35µm slit is the workhorse option, ideal for general stellar classification, analyzing emission lines in planetary nebulae, and capturing spectra of moderately bright comets and supernovae.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the main purpose of the Alpy \u0026amp; UVEX 35 µm slit?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eIt serves two critical functions. The precision-cut \u003cstrong\u003e35 µm slit\u003c\/strong\u003e acts as the entrance aperture for the spectrograph, determining the resolution of the spectrum. The reflective surface around the slit acts as a \u003cstrong\u003eguiding mirror\u003c\/strong\u003e, allowing you to see the star field and keep your target perfectly centered for the duration of an exposure.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the 35 µm slit affect the spectral resolution of my Alpy or UVEX?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe slit width is a primary factor in determining spectral resolution. A narrower slit produces a sharper, higher-resolution spectrum, allowing you to resolve finer details. The \u003cstrong\u003e35 µm slit\u003c\/strong\u003e provides a strong intermediate resolution, suitable for many projects from stellar classification to emission line studies in nebulae.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhen should I choose the 35 µm slit over a narrower one for my Alpy\/UVEX?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYou should choose the \u003cstrong\u003e35 µm slit\u003c\/strong\u003e when light throughput is as important as resolution. While a narrower slit (e.g., 25µm) offers higher resolution, it passes less light, requiring longer exposures. The 35µm slit is ideal for moderately faint targets or when seeing conditions don't support the highest possible resolution.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use the Alpy \u0026amp; UVEX 35 µm slit for guiding on my target star?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, absolutely. The component is a guiding mirror with a slit at its center. The light from your target that doesn't pass through the slit is reflected into your guiding camera, allowing you to monitor the star's position and make precise tracking corrections.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the 35 µm slit a good choice for observing faint nebulae like the Orion Nebula (M42) with a Shelyak spectrograph?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, the \u003cstrong\u003e35 µm slit\u003c\/strong\u003e is an excellent choice for targets like the Orion Nebula (M42). It allows enough light from the extended object to pass through to achieve a good signal-to-noise ratio in a reasonable time, while still providing enough resolution to separate key emission lines like Hydrogen-alpha and Oxygen-III.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eFor measuring the redshift of a bright quasar like 3C 273, would the 35 µm slit be appropriate for my UVEX?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe \u003cstrong\u003e35 µm slit\u003c\/strong\u003e is a very capable option for a bright quasar like 3C 273. It provides a good balance, capturing enough light for a clear continuum while delivering the resolution needed to accurately measure the shift in prominent spectral lines, such as the broad Hydrogen-beta line used for redshift calculations.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eSlit Width\u003c\/td\u003e\n\u003ctd\u003e35 µm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCompatibility\u003c\/td\u003e\n\u003ctd\u003eShelyak Alpy and UVEX series spectrographs\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eAlpy \u0026amp; UVEX 35 µm slit\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Shelyak_Alpy_600_Manual.pdf\" target=\"_blank\"\u003e\u003csvg class=\"DAV-img-box\" viewbox=\"0 0 512 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"\u003e\u003cpath d=\"M0 64C0 28.7 28.7 0 64 0L224 0l0 128c0 17.7 14.3 32 32 32l128 0 0 144-208 0c-35.3 0-64 28.7-64 64l0 144-48 0c-35.3 0-64-28.7-64-64L0 64zm384 64l-128 0L256 0 384 128zM176 352l32 0c30.9 0 56 25.1 56 56s-25.1 56-56 56l-16 0 0 32c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-48 0-80c0-8.8 7.2-16 16-16zm32 80c13.3 0 24-10.7 24-24s-10.7-24-24-24l-16 0 0 48 16 0zm96-80l32 0c26.5 0 48 21.5 48 48l0 64c0 26.5-21.5 48-48 48l-32 0c-8.8 0-16-7.2-16-16l0-128c0-8.8 7.2-16 16-16zm32 128c8.8 0 16-7.2 16-16l0-64c0-8.8-7.2-16-16-16l-16 0 0 96 16 0zm80-112c0-8.8 7.2-16 16-16l48 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 32 32 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 48c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-64 0-64z\" fill=\"#0047a7\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eShelyak Alpy 600 Manual\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/davidastro.com\/pages\/shelyak-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eShelyak 1-Year Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Shelyak","offers":[{"title":"Default Title","offer_id":52943049195805,"sku":"SHK-SE0150","price":221.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Shelyak-Alpy-UVEX-35-m-slit-1_b2bb2b2b-316f-4f80-84b8-877210aaf9ff.jpg?v=1789616376","url":"https:\/\/davidastro.com\/en-us\/products\/shelyak-se0150","provider":"David Astro","version":"1.0","type":"link"}