HP ACC2 Aurora manual Focusing

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CHAPTER 15 FOCUSING:

One of the drawbacks of a digital camera with no analog output is the difficulty to focus it. The Unis/UiO cameras consist of three adjustable lenses for focusing.

1)Front fisheye lens:

This should use the UV filter setting in the lens filter setting. (MARK: This is not the interference filter wheel, 630.0nm, … .) This UV filter is marked with white characters. The other filters are marked with yellow or red characters. The lens settings in the front fisheye lens should be set fully

open (f-stop to f4) and focused to ∞ .

2)The middle lens:

This is the filter re-imaging optics, CANON camera lens in front of the image intensifier.

As with the other lenses it should be set fully open (f-stop , f0.95). The focus of this lens has to be adjusted.

3)The bottom lens:

This is the intensifier re-imaging optics. This is the NIKON camera lens in front of the CC200 camera head.

As with the other lenses it should be set fully open (f-stop, f1.2). The focus of this lens has to be adjusted.

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Only the PMIS program is used when focusing the camera. The user knows from the experience with the sequence files the best settings for the image intensifier gain and exposure time for the various filters (and for the open filter). When focusing towards stars (or planets) the filter settings with open filter should be used, then a shorter exposure time must be selected.

One person should watch and control the computer while the other person turn the lenses in the camera hut.

The focusing can be done as:

user->comopen->1 user->filterwheel->1 user->initgain->1 user->initpower->1 user->shutterctrl->1

Be careful now, no lights in the camera hut. The intensifier is now continuously exposed to light and could easily be damaged.

Then in the Image_1 window: