My minolta maxxum 7d won't take a picture....The shutter will push down but no picture will be taken. I tried it later in the day then it worked. Now today I tried, it worked this morning and then not again...what could be wrong with it

Go into the settings and select Clean CCD. It should be under the blue menu. The shutter curtain has a tendency to stick on this model. There was a recall on them way back when they first came out.

This is a common problem with the 7D. The shutter curtain will stick after several years of service. Put the camera in clean mode to get the curtain to lift, or send it to Sony to replace it. It was a design flaw by Minolta.

In the camera setup page2 set "File # memrory" to ON
From now the pictures are recorded on the CF card with the shutter counter number (for example Pict8194.jpg or Pict8194.mrw)
You can read this when you look at the pictures with the play button and press the dial UP, the third line from the bottom shows the directory and the counter number (for example 100KM023-8194,

Are the pictures in focus? Does your viewfinder have a diopter correction?

Quite right too. When the M42 adaptor is fitted there is absolutely no exchange of information between the lens and the body: M42 lenses pre-date all of those later developments. Your camera will also be unable to stop down the lens automatically when taking the picture, most M42 lenses don't even stop down automatically when connected to an M42 body.

You need to do things the old-fashioned way. Your camera needs to be set to meter manually, shutter priority mode may also be used. In manual mode you focus the lens as normal with the aperture ring set to the lowest aperture number (i.e.aperture is wide open).
You then make sure that the lens in in manual mode as well and stop down to whatever you want, if the image remains bright enough then you can adjust the precise focus using the hyperfocal principle if you like which takes advantage of the increased depth of field of a stopped down lens.
In manual mode, you then tell the camera what aperture you have set (read it from the lens barrel) and set the shutter speed using the camera's light meter to guide you. If using shutter priority mode then the camera will choose the shutter speed for you.
Check everything is set as you intend and press the shutter.

It all sounds long winded but is exactly how many of the world's greatest photos were taken and soon becomes second nature. You also learn far more about the relationship between aperture, shutter speed and ISO settings and will be able to talk about reciprocity like you know about it!

Yes this is a common problem. Set the camera to take a long exposure shot (5 seconds) and with the lens off take a photo. Can you see the ccd or just the shutter (black)? If its just the shutter the shutter is jammed. It's basically a question of persisting with rebooting the camera and taking shots until the shutter frees itself.

your having a problem with the antishake

I was cleaning my CCD and damaged the shutter. Same problem. Click to take a picture and the camera locks up and powers off. Turn the camera back on and the shutter releases and the camera resets and powers on. $281 service call later and Precision fixed it quickly. Replaced the shutter. They warranty their work for 6 months. Priced way too high, but nobody would touch it. As soon as I told other repair services how I messed it up, they turned me down. I had to much money invested in the camera to toss it in the closet.

There is a known problem with the 7D and some early 5D's where sometimes when you turn the camera on and take a picture it is all black and the camera locks up. You can turn it off and back on and the problem goes away for awhile. Don't know if this is what ou are experiencing. If it is, Sony (who bought out Konica Minolta's camera division) will fix the problem for free. Just had this repaired on my 7D.

This is a known design defect in the cameras and Sony is repairing them, even if your warranty is expired.

see this for Konica Minolta's official statement:
http://ca.konicaminolta.com/information/20070202/01_en.html

it'll direct you to a sony page where you can sign up to get your camera repaired!

more info can be seen here:
http://www.dyxum.com/columns/other/First_Black_Frame/First_Black_Frame.asp