Orion PARSEC 8300M User Manual download pdf (Page 8)

14 15

arrow button next to the preset name to

manage your presets, including Update

Current Preset, and Save As New

Preset. See MaxIm DL’s Help Topics

for more detailed information.

Readout Mode

In the Expose Tab, select Normal for

the best image quality, and Fast for a

quicker image download.

Frame Type

Choose, Light (Raw or Color for the

8300C), Bias, Dark, and Flat. Please

read section 5, “Astronomical Imaging”

to determine when and why to take a

dark or ﬂat.

Fan Speed

Select Camera Settings in the Expose tab (Figure 14.1) to access the fan speed,

High, Medium, or Low (Figure 14.2). High is recommended for the best cooling

performance.

There are a large slew of settings in the Camera Control Window’s Expose tab.

Please read MaxIm DL’s Help Topics which covers all the settings in greater detail.

3.2. The Screen Stretch Window

The function of the Screen Stretch Window (Figure 13) is to properly map the

image brightness levels captured by the camera into corresponding image bright-

ness levels on the computer screen. A typical camera image has each pixel (light

detecting site, over eight million pixels form a single Parsec image) represented

as a number (from 1 to 65535) depending on brightness. This has to be mapped

into the video monitor’s brightness range (from 1 to 255). It is important to set the

screen stretch appropriately, or a great image may look terrible!

When an image is displayed, you will notice a graph in the Screen Stretch

Window. This is called the “histogram” of the currently displayed image. A histo-

gram is a simple bar graph that shows the range of brightness in an image. Each

bar in the graph represents a level of brightness; the bar to the far left in the histo-

gram represents the dimmest pixels, and the bar to the far right is for the brightest

pixels. The height of the bar is the total number of pixels at that brightness level

in the image. Every image has a different histogram depending on how much of

the image is bright or dark. Directly viewing the histogram of your image in the

Screen Stretch Window provides an easy interface for making decisions on how

the screen stretch should be set.

In Maxim DL, the two parameters entered in the Screen Stretch Window are

Minimum and Maximum. A pixel that is at the Minimum value is set to zero (black),

and a pixel at the Maximum value is set to 255 (white). An easy way to adjust the

Maximum and Minimum values is to

move the slider arrows located directly

under the histogram of the image in the

Screen Stretch Window. The red slider

arrow corresponds to the Minimum

value and the green arrow corresponds

to the Maximum value. Simply left-click

and then drag each arrow to adjust it

to the desired level. The best results

are obtained by adjusting the arrows

(numbers) until the most pleasing dis-

play appears.

There are also seven automatic settings in the Screen Stretch Window. Typically,

Medium will give good results for deep sky objects, so the default screen stretch

setting is Medium.

Instead of using the Screen Stretch Window, it is faster to use the Quick Stretch

facility. This allows you to modify the image appearance instantly with small up/

down and left/right movements of the mouse. To do this, hold down the Shift key,

then left-click and drag the mouse on the image. You’ll ﬁnd this feature to be a

great convenience when ﬁne adjusting the screen stretch to get an image to look

its best.

The trick with stretching is determining exactly how to stretch the image for best

effect. Often there are several different possibilities for the same image. Trial-and-

error will be the best way to judge what the best screen stretch setting is. Try

Figure 14.1. The Camera Settings is found in the Expose tab.

Figure 14.2. Adjust the Fan Speed in

the Parsec Settings.

Figure 13. The Screen Stretch

Window is a histogram that allows you to

adjust the apparent brightness levels of an

image on your screen.

Number of pixels at

brightness level

Range of brightness levels

1 2 3 4 5 6 7 8 9 10 11 12 13 ... 22 23

Comments to this Manuals

No comments

Orion PARSEC 8300M User Manual Page 8

Comments to this Manuals

Related products and manuals for Camcorders Orion PARSEC 8300M