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Our Customer Pictures Page

The following pictures were taken by our customers. Only small thumbnails versions are shown on this page but click on a picture and the full size picture will display. By only having small versions of the pictures on the page it loads much faster for those with slow internet connections.

Mike's First Spectrum Picture:

The following picture is Mike's very first spectrum picture taken on 8/19/05 from his observatory in Tennessee. It is the spectrum of the star Vega using his SBIG ST-10 camera with a Type D1 - DG Filter mounted in his SBIG CFW-8a filter wheel. This is the untouched B/W picture with an average of (12) 20 second images acquired with the ST10XME on a 106 mm apo refractor. The camera was binned 2x2 (resolution 1092 x 736). The DG Filter was located 25.9 mm from the ST-10's focal plane and was focused on the near IR end above 810 nm of the spectrum which is one reason the spectrum resembles an arrow pointing to the right.

The Detail he captured is Exceptional. The first two Hydrogen series lines just jumped out at you - Without having to do Any Processing at All! Using the Quick Calibration procedure the distance to the Hb line was found to be 481 pixels. The Hb line has a known wavelength of 486.133 nm. But Vega has a Radial Velocity of -14 km/sec which will change this wavelength as its been Red Shifted. Using our Red Shift Calc Spreadsheet we find the observed wavelength for the Hb line Mike photographed is really 486.103 nm.

Putting these numbers in the reference section of the Spectral Tool Spreadsheet (Reference Wavelength = 486.103 and the Base Line Distance to Reference = 481 pixels) will calibrate this Tool to Mike's camera + D1 Filter setup. This will allow the wavelengths of all the other lines in his image to be quickly determined to within a few nanometers as soon as their distance from the center of Vega's image is measured and entered into the Unknown distance box of the Spectral Tool Spreadsheet.

When this is done for the two extreme ends of the spectrum in Mike's photograph we find that his unprocessed image captured Vega's spectrum from 372.7 nm, in the near UV, to 896.9 nm in the near IR. If the image had been processed (for example in Photoshop) you would find the Red end would extend past the 897 nm point.

This image is typical of that produced by a very good refractor. The circular dim blob in the upper right corner of the picture is an out of focus image of a dim star. Spectral images taken with reflecting and SCT telescopes resemble a straight line without any flaring as is seen in this photograph.

Nick's First Spectrum Picture:

This spectrum is Nick's first spectrum taken from his back garden in England. It was taken in November 2005. Its the spectrum of the star Bellatrix. It was taken with a C8 (an 8" SCT telescope) working at f/10. It was taken using a Type A1 - DG Filter on a Meade LPI camera that still had the Meade IR filter in it. You can see how the Red end of the spectrum is cut short at 650 nm. This is due to the red cut-off by the IR filter. The Ha line is located at 656 nm and was lost due to the IR filter's absorption. The image was captured using K3CCD where 50 frames were combined using Regsitax and image processing was finished using Photoshop CS2. The two tick marks are the Hg (Hydrogen Gamma) line at 434.047 nm, and the Hb (Hydrogen Beta) line at 486.133 nm.

Notice how the image of the star is blurred and the image of the spectrum is sharp and spectral lines can be seen. This is because to get a good spectrum picture you need to focus on the spectrum and not the object, which blurs the object's image. Also notice that the spectrum is rectangular in shape. This is characteristic of a mirror system (like a SCT) as opposed to a lens system as used my Mike in his APO picture above.

Bellatrix is a 1.69 magnitude star with a radial motion of +18 km/sec. This motion will shift the observed wavelength by about 0.03 nm from the rest wavelength. So the observed Hg line is really seen at 437.073 nm, and the Hb line is really seen at 486.162 nm.

Nick's Composite Spectrum Picture:

During December of 2005, Nick took the spectrum of several of the stars making up the constellation Orion using his A1 and B1-S DG Filters on his LPI camera and then superimposed these spectrums onto a picture of the appropriate stars in the constellation. His LPI camera had the IR Blocking removed.

Really a NICE job Nick. Congratulations.

Nick's Spectral Line Analysis:

Using the tools on the CD that came with his DG Filters Nick was able to identify several of the elements of the stars that make up the Orion constellation. He used a modified LPI camera (on his C8 telescope), that had its IR Blocking Filter removed - which gave it extended Red and IR sensitivity. He used the procedure on our web page (also on the CD) to remove the LPI's IR Blocking filter from his camera.

In the course of only one month Nick had progressed from his first picture to being able to identify the individual elements in a star's spectrum with confidence.