ToupTek and Altair Camera Known Issues & Optimizations

Cameras utilizing ToupTek mainboards and OEM derivatives (including Altair Astro, Omegon, RisingTech, MallinCam, and Ogma) operate under the indi_toupcam_ccd or indi_altair_ccd drivers. Specific hardware models exhibit documented idiosyncrasies requiring custom driver configuration.

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1. Frame Quadrant Artifacts (Overlapping Quads)

Symptom

Certain Altair and ToupTek models (notably IMX585, IMX571, and IMX290 variants) intermittently initialize with severely corrupted frames displaying four horizontally and vertically shifted sub-quadrants divided by a black band at the top of the frame.

Root Cause

This artifact is caused by the camera driver defaulting to an RGB demosaicing mode using incomplete or unaligned frame buffers rather than direct sensor bayer readout.

Resolution

Force the driver to stream frames in native INDI_RAW format. In the camera configuration (INDI Configuration -> Custom Properties / Switches), define:

{
    "PROPERTIES": {},
    "SWITCHES": {
        "CCD_CAPTURE_FORMAT": {
            "on": [
                "INDI_RAW"
            ]
        }
    }
}

Reference discussions:

• GitHub Issue #1840
• GitHub Discussion #2397

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2. Sensor Resolution and Conversion Gain Presets

ToupTek camera drivers frequently initialize in a binned or lower-resolution preview mode by default. To operate at maximum optical resolution and optimize conversion gain, insert the appropriate switch configurations:

ToupTek ATR3CMOS / AE676C (Sony IMX676)

{
    "PROPERTIES": {},
    "SWITCHES": {
        "CCD_RESOLUTION": {
            "on": [
                "3536 x 3536"
            ]
        },
        "TC_CONVERSION_GAIN": {
            "on": [
                "GAIN_HIGH"
            ],
            "off": [
                "GAIN_LOW"
            ]
        },
        "CCD_CAPTURE_FORMAT": {
            "on": [
                "INDI_RAW"
            ]
        }
    }
}

Altair GPCAM3 678C (Sony IMX678)

{
    "PROPERTIES": {},
    "SWITCHES": {
        "CCD_RESOLUTION": {
            "on": [
                "3840 x 2160"
            ]
        },
        "TC_CONVERSION_GAIN": {
            "on": [
                "GAIN_HIGH"
            ],
            "off": [
                "GAIN_LOW"
            ]
        },
        "CCD_CAPTURE_FORMAT": {
            "on": [
                "INDI_RAW"
            ]
        }
    }
}

Altair Hypercam 178C (Sony IMX178)

{
    "PROPERTIES": {
        "CCD_CONTROLS": {
            "BandWidth": 40
        }
    },
    "SWITCHES": {
        "CCD_RESOLUTION": {
            "on": [
                "3040 x 2048"
            ]
        },
        "CCD_CAPTURE_FORMAT": {
            "on": [
                "INDI_RAW"
            ]
        }
    }
}

Altair GPCAM2 / GPCAM3 290C (Sony IMX290)

{
    "PROPERTIES": {},
    "SWITCHES": {
        "CCD_RESOLUTION": {
            "on": [
                "1920 x 1080"
            ]
        },
        "CCD_CAPTURE_FORMAT": {
            "on": [
                "INDI_RAW"
            ]
        }
    }
}

Altair GPCAM2 224C (Sony IMX224)

{
    "PROPERTIES": {},
    "SWITCHES": {
        "CCD_RESOLUTION": {
            "on": [
                "1280 x 960"
            ]
        },
        "CCD_CAPTURE_FORMAT": {
            "on": [
                "INDI_RAW"
            ]
        }
    }
}