Telescopi Italiani TI35 f/5.0 Modified Harmer Wynne Astrograph
Price as Configured: $0.00
Tell us what you're looking for, and we’ll point you in the right direction. Email Us.
Italian Telescopes TI35 f/5.0 — 350mm Aperture, 1750mm Focal Length, 87mm Corrected Field
The Italian Telescopes TI35 f/5.0 is a 350mm (13.8") Modified Harmer Wynne astrograph offering 1750mm of focal length in a transportable carbon fiber tube weighing under 19kg. Designed by Telescopi Italiani — the Italian optical engineering firm founded by Leonardo Priami and Claudio Dandolo — the TI35 f/5.0 delivers a true diffraction-limited corrected field of 87mm in diameter, making it one of the largest corrected fields available in a portable instrument of this aperture class. Deep Space Products is proud to offer the TI35 f/5.0 as the U.S. dealer for Italian Telescopes, backed by our team's deep expertise in pairing precision optics with the mounts and observatory systems that get the most out of them.
Why imagers choose the f/5.0
For astrophotographers working with modern large-format sensors — full-frame and medium-format CMOS cameras — the corrected field diameter is every bit as important as the aperture. The TI35 f/5.0's 87mm diffraction-limited image circle fills sensors like the Sony IMX455 and IMX461 without compromise, delivering pinpoint stars from center to corner across all spectral bands. At 1750mm of focal length, the f/5.0 also provides a more moderate image scale than the faster f/3.5 sibling, making it well-suited to mid-size deep sky targets — nebulae, galaxy groups, and extended objects where you want 350mm of light-gathering power without the aggressive framing of a super-fast system. Italian Telescopes describes the f/5.0 as their "all-around" configuration, and that framing is accurate: it's the variant that handles the widest range of imaging subjects with the greatest flexibility.
The 1750mm focal length also pairs naturally with a broader range of narrowband imaging targets, giving finer detail on objects where the f/3.5's wider field is more than necessary. The f/5.0's slightly longer optical path also makes it somewhat more forgiving of focus and tilt variations, which matters in remote and unattended observatory environments.
Modified Harmer Wynne optical system
Both TI35 variants share the same fundamental optical architecture — a parabolic primary mirror combined with a spherical secondary and a three-element ED glass corrector — but the f/5.0's geometry produces a wider corrected image circle while maintaining the same spectral coverage (400nm to 1.2 microns) and near-zero residual color error across the entire field. The corrector is a 116mm diameter, three-element ED design with multilayer coatings spanning 400–900nm, and Telescopi Italiani publishes complete spot diagrams and polychromatic wavefront data for the f/5.0 — documentation that most competitors simply do not provide. Those diagrams confirm diffraction-limited correction across the full 87mm field diameter, not just at center.
The 56% effective obstruction is a deliberate engineering tradeoff. Telescopi Italiani sized the secondary mirror to optimize illumination out to 30mm off-axis with a well-dimensioned secondary rather than under-sizing it to improve a single illumination number at the expense of actual collected light. The result is excellent edge-to-edge brightness on large sensors without sacrificing aperture efficiency.
Carbon fiber construction and built-in automation
The TI35's carbon fiber tube is not cosmetic — it exists because carbon fiber's low thermal expansion coefficient keeps the optical system in focus as temperatures drop during a night's imaging session. The same structural choice gives the TI35 extreme rigidity relative to its weight: at under 19kg for a 350mm instrument, it is genuinely portable by a single person and compatible with mounts from the 10Micron GM2000HPS II through larger platforms. The 740mm tube length and 430mm overall diameter make it compact enough for most roll-off roof and dome observatory footprints that would struggle with longer truss designs.
Built-in automation is standard — not optional. The TI35 includes an integrated electronic secondary mirror focuser (ASCOM Alpaca compatible), onboard control electronics, and Wi-Fi telescope control software. An automated dust cover and field rotator are available as options, both ASCOM Alpaca compatible. Every control input — focus, dust cover, field rotation — is accessible over Wi-Fi without physical access to the telescope, which matters enormously for remote observatory use.
DSP Remote compatibility and observatory integration
The TI35 f/5.0's combination of compact dimensions, Wi-Fi control, and ASCOM Alpaca compatibility makes it well-matched for hosting at DSP Remote, Deep Space Products' Bortle 1 telescope hosting facility in southwest New Mexico. An instrument that can be fully controlled remotely — with no manual intervention required for focus, field rotation, or dust cover management — is exactly what unattended dark-sky hosting demands. Deep Space Products' team has direct experience configuring Italian Telescopes astrographs in remote observatory environments and can advise on the full system stack: mount selection, imaging train layout, control software, and automation.
Fused Silica (Quartz) primary and secondary mirrors are available as a factory option for customers in permanent observatory installations where thermal stability over long unmanned runs is a priority. Fused Silica carries a thermal expansion coefficient of 5.4 × 10⁻⁷/°C — approximately six times lower than standard borosilicate glass — and the near-zero CTE lightweight mirror shape is the preferred choice for any setup where ambient temperature changes significantly between imaging sessions.
Specify your configuration with Deep Space Products
The TI35 f/5.0 is a precision instrument that rewards careful system planning. Deep Space Products works with each customer individually to match the TI35 to the right equatorial mount, imaging camera, filter wheel, and control software for their specific goals — whether that's a portable dark-site setup built around the 10Micron GM2000HPS II or a permanent remote observatory. Contact us to talk through your application, confirm compatibility with your existing equipment, and get accurate lead time and shipping information for your order.
