New Page 6

New Product Announcement
ALL SKY versions of the
ST-237A and STV cameras
Update November 1, 2002: We are now accepting
orders for December / January delivery

Many observatories use an all sky camera to monitor changing sky and weather conditions. Until now, obtaining high quality 180 degree views of the sky required an expensive large format CCD and a similarly expensive fish eye camera lens. Now, however, the ALL SKY cameras make this possible for much less. The lens used in the ALL SKY cameras is a high quality custom mounted 1.24mm F/2.8 fisheye. In order to illuminate the TC-237 CCD with the full field of the fish eye, the rear of the lens must be mounted very close to the CCD. To place the lens at the correct distance, a special housing has been designed that replaces the CCD chamber. The shutter or filter wheel must be removed and a new face plate will be made to cover the front of the camera head. The face plate has provision for a cap that may be used to take dark frames and for protection when the camera head is not in use. Then the entire ST-237AS.or STV head is held in a larger cylinder for weather protection (see photo of unassembled parts below).

The prototype "All Sky" version of the ST-237A camera head.
A new face plate with screw-on lens cap will be added to close the head cavity.

120 second image taken with the ST-237 All Sky camera from moderately light polluted Santa Barbara.
North is up. Polaris is top center and the big dipper is top right.
The milky way is clearly visible despite the bright lights of a shopping center to the south.

This chart was made using TheSky software to show approximately the same field of view as the image above.

One frame from an animation shot from a much darker Kitt Peak location.
Click on the image above to see the full animation.

Update November 1, 2002: The All Sky cameras are ready for production. The All Sky ST-237AS is a modified ST-237A with custom lens and housing for 180 degree field of view. The modifications consist of replacing the front plate, shutter and CCD chamber with a new front plate and CCD chamber. There is no shutter in the All Sky version and filters cannot be used. The new front plate is is larger than the camera head to allow the entire head assembly to fit inside a weather resistant mounting cylinder. A machined aluminum cap is provided to protect the lens when not in use. The CPU must be protected from weather, but the All Sky head is designed to be left outside all the time.

The unassembled parts of the AllSky Cam: CCD Camera head with oversized face plate and fish eye lens,
screw on lens cap and mounting cylinder for weather protection.

The assembled AllSky Cam: Head cable is fed through the open
bottom of the mounting cylinder (Weatherproofing assumes the
All Sky Cam is pointed at zenith). Aluminum lens cap may be
screwed on when camera is not in use.

List price as of this writing for a new ST-237AS is $1995. We are also selling a kit for modifying existing ST-237 (and STV) cameras. The kit contains all the parts necessary for the owner to perfrom the modifications although it is not recommended unless the owner is comfortable making these kinds of mechanical changes to his/her camera head. List price for the kit is $995. Prices and specifrications are subject to change without notice. Current prices may be found at our Price List page. Current specifications may be found at our Product Catalog section.