Using The SSDSI-II As An Autoguider, Batch Process

all saved data will be kept intact. If another Size Format is utilized, there may be some loss of data, especially when saving combined images.

Batch Process

Batch Process can be used to process multiple images simultaneously using the various commands available in MaxIm DL Essentials Edition. The ﬁrst step is to select a set of images or ﬁles.

Image ﬁles can be selected from disk using the Select Files button. You can browse to a location on the disk where your image ﬁles are located, and select a number of ﬁles. Use CTRL-click to select individual ﬁles, and SHIFT-click to select a range of ﬁles. You can see the path for the selected ﬁles by turning on the Show Path check box.

You can also select images already open in MaxIm DL Essentials Edition by clicking the Select Images button. The window that pops-up will indicate all the images currently open. Again, use CTRL-click and/or SHIFT-click to select multiple images. Click OK when done.

You can subsequently remove selected images and ﬁles from the Batch Process list by selecting them with the mouse and clicking the Remove but- ton.

Once all input images have been selected, use the Processing Commands settings to specify which of the commands from the Edit and Process menus will be applied to each of the selected images. Each selected command will be run automatically on each input image. The individual commands must already be set up with the settings you wish to use. The individual commands are run in the same order that you specify them in the dropdown lists.

Select the location for the saved ﬁles using the Path button, or click Write Output to Source Folder to cause the ﬁles to be saved back into the folder from which they were loaded. (This option cannot be used when an image has never been saved, for example, one freshly acquired from a camera.) In the event that saving a ﬁle will cause it to overwrite an existing ﬁle, you can select skip save, overwrite it, or move to subfolder. You can specify the subfolder name in the adjacent ﬁeld. Use Size Format to select between 16-Bit Integer and 32-Bit IEEE Float formats for the processed images. To keep all processed image data intact (especially for stacked images), we recommend using the 32-Bit IEEE Float format. If you need to open the resultant ﬁles in another pro- gram, however, you may need to use the 16-Bit Integer format.

Click OK to start the Batch Process operation. Successfully converted and saved ﬁles are removed from the list box, leaving only those for which an error occurred. In this case, the OK button will change to Retry. To ﬁnd out what error occurred, point the mouse cursor at an image name in the list. The appro- priate error message will appear in the Status Bar at the bottom of the MaxIm DL Essentials Edition main window.

Using The SSDSI-II As An Autoguider

A great feature of the SSDSI-II is its ability to be used as an autoguider for tele- scope mounts. You can use the SSDSI-II to autoguide a mount while images are being taken with another camera, such as a DSLR or another SSDSI-II.

Tracking errors are usually sufﬁciently small on short duration images (15 to 90 seconds depending on the mount) that guiding is not required. Therefore a series of short exposure images can be taken and combined together later using the Combine command. However, in many cases a single long exposure is superior due to the elimination of extra readout noise and the residual blur- ring caused in realigning the images.

When taking long exposures with astronomical telescopes, motorized tracking is required to compensate for the Earth’s rotation. Most telescope mounts do not track accurately enough for long-exposure imaging without some form of additional “guiding”. Manual guiding can be done by an observer watching a star (“guide star”) through a telescope (“guide scope”) mounted next to the main imaging telescope (on the same mount). The observer makes manual corrections to the motor drives via a pushbutton hand controller to keep the star centered in the guide scope’s eyepiece over time. In this way the track- ing accuracy of the main telescope (with imaging camera attached) can be assured. Stars in the resultant images will be crisp and round. Manual guiding can be very tiresome and tedious, however, especially if taking many long exposures throughout the night.

The SSDSI-II can be used as an “autoguider” to take the place of the observer so that no manual guiding corrections are needed during long exposure imag- ing. Keep in mind, however, that when the SSDSI-II is used in this way, you will need another telescope and camera (such as a DSLR or a second SSDSI-II) on the mount to actually take images with; the SSDSI-II takes the place of the observer viewing through the guide scope, but cannot autoguide and image at the same time.

So, in order to use the SSDSI-II as an autoguider, the following equipment will be required:

•Astronomical telescope mount capable of accepting autoguider drive com- mands.

•Cable to connect computer (serial port) to mount’s autoguider jack (mount speciﬁc).

•Main telescope for imaging.

•Camera for imaging.

•Guide scope for guiding.

•Any required rings or brackets for guide scope attachment to the mount along with the main telescope.