Photography

This part of the site is to show some photography I take over the time.

Click one of the section below to enter a gallery.
After that you can find a subject of interest by using the powerful selection engine at the top of the next page.

The default resolution is 640x480 but for some images you can select a much bigger one.

 Astronomy

Astronomy images.

Exhibition by Patrick Chevalley (529 photos in total)
Some of the last photos added to this gallery:

740663 PHOTO HAVE BEEN VIEWED TO DATE

Please set your monitor to distinguish each cell of the below gray scale. Take a specific attention at the low light level, it should be a very small difference between the first two cells.

For a more precise setting:

The chart on the right enables you to set the black level (brightness) and estimate display gamma over a range of 1 to 3 with precison better than �0.1.
The gamma pattern is on the left; the black level pattern is on the right. Before using the chart, the monitor should be turned for on at least 15 minutes (30 preferred).

Gamma is estimated by locating the position where the average intensity across the gamma pattern is constant. The corresponding gamma is shown on the left.
You should be far enough from your monitor so the line pattern isn't clearly visible.

Your monitor's gamma should be close to 1.8 or 2.2.

Black level (brightness) Your monitor's brightness control (which should actually be called black level) can be adjusted using the mostly black pattern on the right side of the chart.
This pattern contains two dark gray vertical bars, A and B, which increase in luminance with increasing gamma. (If you can't see them, your black level is way low.)
The left bar (A) should be just above the threshold of visibility opposite your chosen gamma (usually 1.8 or 2.2)-- it should be invisible where gamma is lower by about 0.3.
The right bar (B) should be distinctly visible, brighter than (A), but still very dark.

There is considerable interaction between the brightness and gamma settings-- increasing brightness decreases gamma-- so you may have to go back and forth two or three times (the contrast setting should have little effect on the interaction).
The vertical bars correspond to normalized luminances of 0.002 and 0.006 at the specified gamma.

Thank's to Norman Koren for it's authorization to reproduce this from is web page.
You can find an incredible amount of information in the original page.

Latest News:

Change default image size
[2007-09-06 21:04:00]

As big screen is now the norm I change the default image size from 640x480 to 1024x768.
The others sizes are still available using the size box at the bottom of the page.


Finally got a DSLR!
[2006-11-01 20:46:00]

This Sony Alpha 100 look not too bad at astrophotography.
The first result are here, I include some full size crop to appreciate the image resolution.


New update
[2005-01-15 15:47:00]

All 2004 images are now online with also images taken with the new Meade DSI in January 2005


Jupiter images
[2003-11-13 18:30:00]

Add 200 images of Jupiter taken from August 2000 up to now.


New old images
[2003-10-07 22:28:00]

Add images taken at La Silla in 1982.


New photos are online
[2003-10-03 12:00:00]

OK, the site is now working and a first selection of recent image added to the Astronomy gallery.

More to come in the next days.