- Customer group: Guest
-
- Register
- Login
- Your account
- Home
- Details
Products description
04. Comparison of various cameras for the Sol’Ex (SolEx)
Various cameras can be used with the Sol'Ex. These cameras and their properties in relation to the spectroheliograph are listed here.
ASI178MM camera
Illustration of the spectrum when a 4.5 mm slit is used
Image size: | 3896 pixels x 2080 pixels - Pixels size: 2.4 microns |
Spectral sampling (for blnning 1x1): | 0.0626 A/pixel |
Maximal focal for capture full solar disk: | 480 mm (slit limitation) |
Anmerkungen: Das Spaltbild (rechts und links) passt mit einem kleinen Spielraum auf die Breite des Sensors. Dies ist eine absichtliche Anpassung, die bei der Entwicklung von Sol'Ex vorgenommen wurde. Diese Konfiguration wird als perfekt für Sol'Ex angesehen.
ASI290 Mini camera
| Image size: 1936 pixels x 1096 pixels - Pixel size: 2.9 microns Spectral sampling (for blnning 1x1): 0.0726 A/pixel Maximum focal point for capture full solar disk: 380 mm (camera limitation) | |
Notes: The entire slit image no longer fits within the width of the sensor. The focal length of the telescope should not exceed 380 mm if the image of the solar disk is to be acquired in a single pass. A 31.75 mm extension tube is used at the interface to ensure sharpness.
ASI174 Mini camera
| Image size: 1931936 pixels x 1216 pixels - Pixel size: 5.86 microns Spectral sampling (for blnning 1x1): 0.1450 A/pixel Maximum focal point for capture full solar disk: 480 mm (slit limitation) | |
Notes: The slit image largely fits the width of the detector.
The sensor is characterized by a large pixel size. The spectral sampling is insufficient to capture Sol'Ex's full spectral performance. The image is significantly undersampled, making it difficult to accurately observe the wings of the H-alpha lines and to examine the finer lines. The contrast of the images in the H-alpha line is also reduced.
However, the effective bandwidth of the order of 0.3 A is on the level of good interference filters, meaning it is still possible to acquire good images in this line.
The resolution of details on the solar disk is also somewhat compromised compared to a camera with smaller pixels, such as an ASI178MM.
On the other hand, this camera is perfectly suited for observing the H and K lines of Ca II in the UV, which have much lower spectral resolution requirements. The image is also very bright in an area of the spectrum where there is a lack of luminosity.
ASI183MM Pro camera
Image size: | 5496 pixels x 3672 pixels - Pixels size: 2.4 microns |
Spectral sampling (for blnning 1x1): | 0.0626 A/pixel |
Maximal focal for capture full solar disk: | 480 mm (slit limitation) |
Notes: We're entering the category of "large" cameras equipped with Peltier cooling. The size is impressive, but it should be noted that there is an adaptation to Sol'Ex and that we are able to focus the spectrum.
It is possible to acquire solar "scans" with such a large-sensor camera, but of course, the ROI ("cropping") is more than necessary. The entire image of the slit no longer fits within the width of the sensor. This configuration will be particularly effective for Star'Ex because of its cooling capability (or if a different slit is installed in the future).
ASI294MM Pro camera
Image size: | 8244 pixels x 5644 pixels - Pixels size: 2.32 microns |
Spectral sampling (for blnning 1x1): | 0.0605 A/pixel |
Maximal focal for capture full solar disk: | 480 mm (slit limitation) |
Notes: This is also a large camera with a cooling system. The situation with this camera is complicated because, if you look at the official ZWO documentation, you can see that it is described as having 4144 x 2822 pixels with 4.64 micron pixels. In reality, this camera, which is based on a color model, has a mode that is twice as powerful, which some software (e.g., Prism) can read. Ultimately, this is the camera that samples the spectrum most finely. However, as can be seen in the image above left, the spectrum takes up less than half of the usable area. Christian was able to successfully use this camera (together with the ASI183MM Pro) for solar scans by performing the necessary cropping.
ASI6200MM Pro camera
Image size: | 8244 pixels x 5644 pixels - Pixels size: 2.32 microns |
Spectral sampling (for blnning 1x1): | 0.0605 A/pixel |
Maximal focal for capture full solar disk: | 480 mm (slit limitation) |
Notes: This camera falls outside the category due to its size, format (24 x 36), and price (the ASI2600MM Pro model is slightly cheaper, with a smaller sensor but equivalent features).
This configuration is shown for demonstration purposes and as a curiosity.
Sony Alpha DSLR
Sol'Ex can be used with a digital camera (APN). The ability to capture "true" color images with this camera is of interest for learning how a spectrograph works and the general principles of spectrography. Color imaging of spectra is a potential educational approach.
Many digital cameras can also be connected to large screens via the HDMI interface, an ideal solution for public demonstrations. However, it is not practical to perform solar scans with this type of device (pixel size, Bayer matrix, reading mode, etc.).
A small set of additional parts is required to obtain a clear image, tested here with the Sony Alpha series. This "APN kit" includes an "APN tube" for a helical focusing system, an "APN spacer," and an "APN ring." This set is intended for use with the 125 mm focal length lens. Another use of "APN_tube" can be found in the "Stars" section.
This Product was added to our catalogue on 14/11/2022.
Die Box kann unter tpl_modified/boxes/box_miscellaneous.html verändert werden. Die Sprachvariablen befinden sich in der Datei tpl_modified/lang/german/lang_german.custom.