Star Focus Assistant is a utility developed to help astrophotographers using a DSLR camera focus their camera while viewing an object in real time.
This requires that your camera have the ability to send a real time or "Live View" image to your computer so that you can see your "target" image change focus as you turn the focus ring on your camera lens.
Star Focus Assistant does this by tracking a slowly moving bright spot (your focus star) and magnifying dynamically a portion of your display. "Star Focus Assistant" uses pixel information from this "Live View" image.
When you launch Star Focus Assistant, you see a small "Control Panel" and a larger "Display Window".
Star Focus Assistant operates in two modes: "Normal" and "Auto Track".
In "Normal" mode, the "Display Window" background displays a magnified view of the desktop area around your cursor. As your cursor moves around the screen, you see the image inside the "Display Window" change as well.
Located in the middle of the "Display Window" is a "Red Box" that surrounds the nine cells around your cursor. This "Red Box" identifies the cells used by the tracking algorithm.
In "Auto Track" mode, you identify a bright spot you want to track across the display, move the cursor over this spot and then press the "Command-Option" keys to activate the automatic tracking function.
You will see "AT Mode" displayed in red font to the right of the "Hide/Show" button in the "Control Panel". A specially developed algorithm will keep your cursor close to the bright spot as it moves.
To leave the "Auto Track" mode so that you can use your mouse and cursor for other computer operations, press the "Command-Control" keys to revert to the "Normal" mode.
The "Control Panel" provides two controls.
There is a button to "Show" or "Hide" the "Display Window".
There is an up/down selector to increase or decrease the "Magnification" level (10x to 30x) of the computer display area inside the "Display Window".
Using "Star Focus Assistant" In The Field: (Note: The instructions listed below use Canon`s EOS Utility program and its "Live View" viewing capability to illustrate how to use "Star Focus Assistant" in the field. Other camera manufacturers may have similar utility programs for their cameras equipped with the "Live View" feature.)
Setup your camera and computer just as you would for any typical imaging session.
Select a bright star to use for your focus routine.
Use whatever program works for you (e.g., Canon EOS Utility, Nikon Camera Control Pro, etc.) to set your camera to BULB, the lowest F-stop for your lens, and an ISO of 1600 or so.
Activate the "Live View" feature on your camera. In the EOS Utility program, select "Camera settings/ Remote shooting", then the "Tool" menu selection at the top of the screen, then the "Remote Live View shooting" option from the drop-down menu and center your focus star in the display.
With your focus star centered, click on the 10x magnification button in the lower right corner of the screen (Canon EOS Utility).
Launch "Star Focus Assistant" and position the "Control Panel" and "Display Window" off to the side.
Place your cursor near your target star. You will see the area around your cursor appear inside the "Display Window". Place your cursor inside the star`s bright center and press the "Command-Option" keys to activate the "Auto Track" feature. "Auto Track" will now keep the star`s image inside the "Display Window" so that you can concentrate on focusing your camera lens.
As you rotate your camera lens`s focus ring, notice that the image in the "Display Window" is surrounded by red or blue pixels. This indicates that the image is out of focus.
When the image is as white and free from colored pixels around its periphery as possible, your image should be in focus. From this point forward, don`t touch the focus ring on your lens.
All you have to do next is quit Star Focus Assistant and take some great pictures.
Limitations:
· 10 launches trial.
