Pixinsight Lerar Link -

Let me know, and I’ll give you a precise review of the specific product you meant!

PixInsight , "lerar" is likely a misspelling of , specifically referring to the function found in the Screen Transfer Function (STF)

process. This "Linear Link" (or "Linked STF") is a fundamental concept for viewing and color-balancing raw astronomical data. 1. Understanding Linked vs. Unlinked STF

The Screen Transfer Function (STF) provides a temporary "stretch" so you can see your data without permanently altering the underlying linear pixels. PixInsight Linked STF (Link Icon ON):

Applies the same stretch parameters to the Red, Green, and Blue channels. When to use:

After you have performed color calibration (like SPCC). It preserves the color balance you've achieved.

If the image hasn't been calibrated, a linked stretch often looks heavily green or red because raw sensor data is usually unbalanced. Unlinked STF (Link Icon OFF): Calculates an independent stretch for each channel. When to use: pixinsight lerar link

On raw, uncalibrated data. It "neutralizes" the background visually so you can see the nebula or galaxy clearly without a heavy color cast. 2. How to Use the "Link" Feature Open the STF Process: Process > All Processes > ScreenTransferFunction Locate the Link Icon:

It is the small chain-link icon in the top-left corner of the STF window. Toggle the Link: Click to Break the Link:

The icon will no longer be highlighted. Now, when you click the "Nuclear" (Auto-Stretch) button, PixInsight will balance the colors for you visually. Click to Enable the Link: The icon will be highlighted. Use this once you have used SpectrophotometricColorCalibration (SPCC) to ensure you are seeing the "true" calibrated colors. 3. Linear vs. Non-Linear Guide Linear Stage:

Your data remains raw and "dark." Use STF (Linked or Unlinked) to see what you are doing while applying processes like DynamicBackgroundExtraction (DBE) , BlurXTerminator, and SPCC. Non-Linear Stage:

Once you are ready to permanently brighten the image, you "stretch" it using HistogramTransformation GeneralizedHyperbolicStretch (GHS)

. After this, the STF is no longer needed and should be reset. PixInsight Summary Table: STF Link States Icon Appearance Best Use Case Broken chain Viewing raw, uncalibrated stacked data Solid chain Viewing data after SPCC or Color Calibration One-Shot Color (OSC) Let me know, and I’ll give you a

In the Screen Transfer Function (STF), the Link RGB Channels button (represented by a small chain icon in the top left of the STF window) determines how PixInsight calculates an automatic stretch for your image.

Linked Mode (ON): PixInsight applies the same mathematical stretch to all three color channels (Red, Green, and Blue) based on the image's overall statistics.

Unlinked Mode (OFF): PixInsight calculates a separate, independent stretch for each channel. This effectively "neutralizes" the background by aligning the histograms of the individual colors. Why Linear Images Need "Unlinking" Initially

Raw astronomical data often has a heavy color bias, frequently appearing green due to the Bayer pattern of color cameras or atmospheric conditions.

Visualizing Hidden Data: Because raw data is "linear," it looks nearly black to the human eye.

Removing the Cast: When you use an Unlinked STF (Ctrl + Click the "Radioactive" icon), PixInsight stretches the channels separately, which removes that heavy green or red cast and lets you see the actual nebula or galaxy detail. The Workflow: When to Toggle the Link First, we need to create the base color image

Standard processing in PixInsight follows a specific path regarding the STF link:

Initial Viewing (Unlinked): Upon first opening an image, use an Unlinked STF to see through the color cast and gradients.

Color Calibration: Perform processes like SpectrophotometricColorCalibration (SPCC) or BackgroundNeutralization.

Switch to Linked Mode: Once the image is color-calibrated, you must Link the Channels. A Linked STF will now show the "true" balanced colors you just created. If you keep it unlinked after calibration, the STF will override your calibration and show an artificial color balance. Pro Tips for Managing the Link

Beginners often forget to link their dark flats to flats. If your flats and dark-flats have different exposure times or temperatures, WBPP will fail to calibrate the flats, leading to over-correction.

Pro Tip for the “Lerar Link”: Always use the “Show Linked Files” button in WBPP. This visual diagram shows exactly which calibration frame is applied to which light frame. If you see red “X” marks, your linking is broken.

First, we need to create the base color image.

Pro Tip: At this stage, your RGB image might look washed out or have a heavy color cast. This is normal. Use the BackgroundNeutralization and ColorCalibration processes on this RGB image before proceeding.