Sony Cybershot: Display comes up, no picture, black screen shots

5 megapixels or more. In general, unless you're really tight on space or know you're not going to need the resolution, set your camera to its highest resolution (8 megapixels in your case) and leave it there. You can always make a large picture smaller; you can't make a small picture larger.
See page 13 of the Cyber-shot handbook: http://www.docs.sony.com/release/DSCT70_handbook.pdf

Check your lens block it faulty

the memory card Sony, called memory stick have a slider in right side. Slide to unlock and you can continue using you memory stick.

is important for people to share knowledge to hear your comments, rate points

The camera either has a stuck aperture inside the lens or a bad CCD sensor.

The aperture is the opening that allows light to enter the lens. If it's stuck closed no light goes in, so no display on the LCD and solid black pictures. The way to fix it is to replace the lens. You can try tapping or banging the camera on it's side on your hand or even gently on a table. This might unstick the aperture for a short time, but it will just stick again later.

If the CCD is bad the sensor won't show anything other than solid black, or sometimes purple/pink smeared lines. Again the solution is to replace the lens assembly, or look for a used CCD online and just switch that out instead.

Hope this helps!

Thomas Drayton
Owner, Darntoothysam.com Digital Camera Repair

1. Ensure the camera is turned on.
2. If applicable, ensure the lens cover has been removed before taking pictures.
3. Ensure the LCD backlight is turned on by pressing the DISPLAY button several times until the screen appears. NOTE: Depending on the camera model, the DISPLAY button may be labeled as DISP or with a display icon [FIG. 1]. This button could be a standalone button or incorporated as one of the control arrow buttons depending on the model of camera.
   
4. If operating the camera with a battery, ensure the battery is fully charged.
5. Ensure the battery is inserted properly in the camera.
6. If operating the camera with the power adapter, ensure it is plugged into a working AC outlet.
7. Ensure no Audio/Video (A/V) cables are connected for viewing pictures on a TV; the LCD screen will not display when an A/V cable is connected.
8. Perform a reset procedure on the camera.

The troubleshooting steps listed above should resolve your issue. If you have completed all of the steps and the issue is not resolved, service may be required. The Sony Service Web site at http://eservice.sony.com/ can assist you in obtaining service from a Sony Service Center or locating a Sony Authorized Servicer.

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Try to reset the camera to original settings:
How to reset a Cyber-shot® digital still camera back to original factory settings. Solution
Cyber-shot cameras nowadays have a built-in rechargeable battery for retaining time, date, and other settings. Since the built-in rechargeable battery is not removable, current Cyber-shot camera models can only be returned to the original factory settings by pressing a small RESET button on the camera or by using an Initialize option in the menu.
Older-model Cyber-shot cameras (prior to the year 2000) do not have a built-in rechargeable battery and do not have a RESET button or Initialize option in the menu. These cameras require a manual power reset.
IMPORTANT: To determine whether or not your camera has a RESET button or Initialize option, or for other model-specific information to complete any of the steps in this solution, refer to the operating instructions supplied with the product. Manuals are available online in the Manuals/Specs/Warranty section of the Sony® eSupport Web site.
Follow the appropriate procedure below for your camera.
Using an Initialize option in the menu
Since Cyber-shot cameras have different menu system layouts, refer to the instruction manual specific for your camera model.
Using a RESET button

1. Locate the RESET button on the camera.
2. Use a pointed object (like a ballpoint pen) to press and hold the RESET button for 2-3 seconds.
3. After 2-3 seconds has elapsed, release the RESET button.

Performing a manual power reset

1. Turn off the camera.
2. Remove the battery pack.
3. Remove the button-sized lithium battery.
4. Allow the camera to remain without power for 30 seconds.
5. Reinsert the button-sized lithium battery.
6. Reinsert the battery pack.
7. Turn on the camera.

This happened because you are not a camera repair technician. You took a complicated piece of electronic equipment apart without any knowledge of what you were doing. I'm glad that at least, your pics turn out.

Sony makes more than one 10.1MP Cybershot camera. If you know the model number, you can look for the appropriate manual here: http://esupport.sony.com/US/perl/index.pl

http://esupport.sony.com/US/perl/select-system.pl?PRODTYPE=7&NAVDISP=di

the sony DSC-100 is a 5.0-megapixel CCD so you will not get more megapixel from this camera.

the part which comes out when the power is on might have got stuck .. there may be some dust particles. just blow over it or vaccum it..