Important thing to remember! Please read!

The GIOTTO 150 flat field generator is recommended to be used with aperture sizes from 112mm to 174mm. It is highly suggested to choose an illuminated flat panel diameter size that exceeds the aperture of the optical tube to avoid any risk of illumination dropping at the edges due to lack of coverage. Choosing a flat panel too small for the aperture can cause poor results of flat calibration since the illumination might not be completely uniform throughout the field of view. There is maximum internal diameter and maximum illuminated diameter. The illuminated diameter is the variable to consider what GIOTTO size would work best for the telescope being used.

• Flats capture the camera and telescope system's response to a uniformly illuminated white background field of view to reduce or eliminate vignetting and dust shadows in final images
• PrimaLuceLab's GIOTTO series of smart flat field generators emit uniform light source for capturing calibration frames
• GIOTTO 150 is recommended for aperture sizes from 112mm to 174mm, and can be attached to telescope using included plastic thumbscrews that don't cause damage externally to the OTA
• GIOTTO has a control panel with USB-C and WiFi connectivity, making it easy to use with a computer, smartphone, or tablet
• PLAY astrophotography software and dedicated ASCOM driver simplify the process of recording calibration files with GIOTTO
• Virtual HandPad allows for controlling GIOTTO via tablet, and saving preferred settings for future use
• GIOTTO can also be used as a remotely controlled motorized cap with the optional (sold separately) PrimaLuceLab ALTO telescope cover motor, for optimal positioning and automatic opening/closing of telescope.

Astrophotography involves capturing images of dim objects with extremely low light conditions. The quality of these images depends on several variables, including the equipment used, the atmospheric conditions, and the calibration frames captured during the imaging process. Flat, dark and bias frames are three important calibration phases that each address certain issues that can be caused otherwise.

Flats, also known as flat frames or flat field frames, are one type of calibration frame that plays an important role in astrophotography. Flats capture the response of the camera and telescope system to a uniformly illuminated white background field of view. This is done to reduce or in some cases eliminate any vignetting, a phenemenon where the edges of the image appear darker due to telescope optics (it can also be caused by an image circle too large or small for a particular sensor format, in which case flats will not work) and other factors, particularly when a user is conducting wide field astrophotography with a very fast focal ratio and a large camera sensor (at least full frame). A second benefit flat calibration frames provide is remedy from shadows that can appear as dark patches and lines in final frames due to dust in the telescope or camera sensor. While the goal should be to keep dust away from these optical and imaging instruments to begin with, effects from dust leftover can be remedied through flats.

By capturing flat frames, these imperfections and issues can be corrected during the image processing stage. The flat frames provide a reference image of a uniformly illuminated field of view, which can be used to normalize the intensity of the main image and remove the effects of vignetting and dust shadows.

To make executing flat calibration frames a walk in the park, PrimaLuceLab has created the GIOTTO series of smart flat field generators that can help capture these calibration frames for astrophotography. These devices emit a uniform light source that can be used to illuminate the telescope's field of view, creating the necessary flat frames for calibration.

The GIOTTO 150 flat field generator is recommended to be used with aperture sizes from 112mm to 174mm. To attach the flat panel to a telescope, the imager can simply use the included plastic (to prevent exterior OTA damage) thumbscrews to secure the GIOTTO 150 in place. This eliminates the need to hold the flat field generator in front of the telescope during calibration frames or to move the telescope to the zenith if it cannot be held in position by hand.

GIOTTO has a control panel with a USB-C port for connecting to a computer or a PrimaLuceLab EAGLE and also offers WiFi connectivity for wireless control using a smartphone or tablet with the included Virtual HandPad App. It can be powered easily with a 12V power source without the need for a separate power supply, making it convenient to use with an astrophotography telescope.

The PLAY astrophotography software is designed to control GIOTTO and other PrimaLuceLab devices, with a wizard that simplifies the process of recording calibration files. GIOTTO can also be controlled with other Windows astrophotography software via the dedicated ASCOM driver.

The included Virtual HandPad can be used to control GIOTTO without a computer, allowing users to adjust light settings and save preferred settings for future use.

Additionally, GIOTTO can be used as a remotely controlled motorized cap with the optional PrimaLuceLab ALTO telescope cover motor, which can be easily connected to most telescopes using the PLUS clamp to a Vixen or Losmandy style dovetail bar that is installed on many telescope designs on the market. If the dovetail bar is too short, replacing it will a longer one should do the trick! This design allows for optimal positioning of GIOTTO and ALTO to open and close the telescope automatically.

• PrimaLuceLab's ALTO-1 is a peripheral device accessory for the GIOTTO Flat Illuminated covers up to 220mm for telescopes used by astro imagers.
• ALTO-1 functions as a motor for remotely opening and closing telescope covers, making it easier and quicker for users to execute flat calibration frames without needing to be physically present at the telescope.
• Supplied with USB and 12V power passthrough plugs and Cable Locking Clips (CLC) for improved cable management and simplified telescope setup.
• No need for external power units.
• ALTO-1 is a great complementary accessory for the GIOTTO, which is an essential tool in astrophotography for correcting uneven illumination of the camera's sensor via flat calibration process, which can remedy vignetting and dark streaks caused by dust in final results.
• Includes an integrated control system that allows for convenient connection to an EAGLE or regular Windows computer via a USB-C port, enabling control through PLAY software or third-party astrophotography software that supports ASCOM CoverCalibrator.
• To connect ALTO-1 with a telescope, users can use the PLLMORVLP PLUS dovetail clamp as an optional accessory, which can connect ALTO-1 to any Vixen or Losmandy style dovetail bar that are commonly screwed into the vast majority of telescopes on the market.
• It is important to note that using GIOTTO with ALTO-1 cannot seal the telescope front opening, so it is not recommended to use them to record dark calibration frames and instead recommended for a dark library.

PrimaLuceLab has created a peripheral device accessory called ALTO-1, which functions as a motor for the GIOTTO Flat Illuminated covers up to 220mm for telescopes used by astro imagers. With ALTO-1, users can remotely open and close their telescope cover, making it easier and quicker for them to execute flat calibration frames without needing to physically be at the telescope at all times.

ALTO-1 comes with USB and 12V power passthrough plugs that can directly connect to the GIOTTO, as well as Cable Locking Clips (CLC) that can improve cable management and simplify telescope setup. ALTO-1 is designed to run off a 12V power source, eliminating the need for external power units.

As a great complimentary accessory for the GIOTTO, making flats is an essential yet easy step in astrophotography that helps to correct for the uneven illumination of the camera's sensor caused which can result in vignetting and dark streaks caused by dust. When doing long exposure at a wide field of view, astrophotographers will be grateful to have both ALTO and GIOTTO at their fingertips to assist in this crucial step!

The ALTO device has an integrated control system that allows for convenient connection to an EAGLE or regular Windows computer via a USB-C port, enabling control through PLAY software or third-party astrophotography software that supports ASCOM CoverCalibrator. To top it off, it also has WiFi capability, enabling remote control using a smartphone or tablet via the Virtual HandPad app. ALTO doesn't require a separate power unit, as it operates using a 12V power source, which is easily accessible and can be powered together with the astrophotography telescope.

To connect both ALTO and GIOTTO devices to a control computer, there is no need to separately connect USB and power cables to each device. ALTO offers USB and 12V power passthrough plugs that make cable management more efficient. The user can connect short USB and power cables from GIOTTO directly to ALTO, and then only need to connect a USB and a 12V power cable from ALTO to the computer. The computer will identify GIOTTO and ALTO as distinct devices in the device manager, enabling separate control of both devices through the software at all times.

To connect ALTO with a telescope, the imager can use the PLLMORVLP PLUS dovetail clamp as an optional accessory, which can connect ALTO to any Vixen or Losmandy style dovetail bar that are commonly screwed in to the vast majority of telescopes on the market. If the telescope has a short dovetail (which is the case in some optical designs), the user can add a longer dovetail bar to clamp ALTO just above or below the front end of the OTA. By doing this, it allows the user to adjust the positions of GIOTTO and ALTO for optimal opening and closing of the telescope tube. In the lower part of the ALTO body, there are several M6 threaded holes that attach the ALTO to the telescope without the PLUS clamp. However, in this case, the imager must also find a way to fix ALTO on the telescope to allow GIOTTO rotation. It is important to note that using GIOTTO with ALTO cannot seal the telescope front opening, so it is not recommended to use them to record dark calibration frames. Instead, it is suggested to record a dark library.

Difference between dark calibration frames and dark library?

While the end goal is identical, that is, both dark calibration and dark library remedy the issues caused by camera noise, they differ in how and when they can ordinarly be used.

In the case of dark calibration frames, these are exposures that are executed when the telescope tube (or camera lens) is covered, and no light enters the camera sensor. This produces an image data of only the camera's internal noise, which can be subtracted from other images taken during the same imaging session, thus eliminating the effects of it. Dark calibration frames are specific to each individual camera and imaging session, as the amount and type of noise can vary depending on factors such as temperature and exposure time.

On the other hand, a dark library is a collection of pre-calculated dark frames that can be applied to any image. A dark library is created by taking multiple dark calibration frames at various temperatures and exposure times, then averaging them to create a representative sample of the camera's internal noise. This library can then be used to subtract the noise from other images, regardless of when or where they were taken. This is why it is recommended to use this method when using GIOTTO in conjuction with ALTO since the optical tube cannot be fully sealed. Another option is using a dark frame filter as a substitute, especially if using a camera without a mechanical shutter.

ALTO can be managed using the PLAY astrophotography software, which is designed not only to operate PrimaLuceLab devices but also to make astrophotography as seamless and smooth as possible. With the software's unique wizard, the user can quickly adjust the opening and closing position of ALTO and GIOTTO on their telescope, and then remotely control it. For user's who want to use different software, they can use any other third party software as long as it is compatible with ASCOM CoverCalibrator driver.

The PrimaLuceLab ALTO motor can be operated without the use of a computer by connecting a smartphone or tablet to its WiFi network, allowing access to the controls through the Virtual HandPad feature, allows to remotely open or close the telescope cap without requiring a computer, essentially having a tablet or phone serve as a hand controller. Settings can also be saved and reused later.