How do I change the format to jpg only on my Nikon D3100?

You can use the Nikon View program that should have been included with the camera. or you download the current versions of Nikon ViewNX or Nikon Capture available free at Nikon Imaging Products Software

Look here for specs: Nikon D3100

You apparently are shooting in both jpg and raw modes. I do that. So what you have is actually two pictures. The jpg picture is full screen and the raw (nef) picture has the black lines you describe.

I don't know why it does this other than to allow you to recognize which pictures is raw and which is jpg. It is not a problem and picture quality is not impacted in any way.

Your manual should explain fairly clearly the benefits of both formats. You can use the menu to change it to take only jpg or nef pictures and possibly other formats.

When I edit photos, unless I'm in a hurry, I usually make a copy of the NEF photo and edit that. You can make many more changes in an NEF photo than you can in a jpg photo.

In either case, I would suggest you always edit from a copy to protect the original. I think my D-90 allows the use of other formats in addition to jpg, but nef is the only raw format that Nikon uses.

hello, to disassembly the nikon d3100 and change the lcd you need the disassembly instructions and pictures i had found a official service manual that has them and it will help you with that ,you can download it from the below link:
http://goo.gl/AvZHV
Good Luck

Im not sure what lens you are using but the SD card holds your pictures try another card or format the same card it maybe full
test the lens by useing the old lens and shoot good luck

Hello, try to factory reset it, if still does not work and you will need to disassembly your nikon d3100 and change any parts i had found a official service manual that it will help, ypu can download it from the below link:

http://goo.gl/AvZHV

Good Luck

If your SD card is not large in size (mb's) it will oniy hold so many pictures
either format or use another empty card

I will assume you are using OS-10 Snow Leopard or later and a recent version of iPhoto. I would experiment. First I would locate one of your files in Finder and open the picture in Preview to see if the file is basically good. Assuming it is, click on the Apple icon at the upper left of your screen and click 'Software Update' on the pull-down menu. Make sure iPhoto is up to date. Another thing you could try, would be to take one of the files that will not open properly and temporarily changing the file extension from .jepg to .jpg. Both .jepg and .jpg are the exact same format, but it is worth a try.

I found this site that has the service manual: nikon d3100 service manual Download Pdf nikon d3100 service manual Find...

Hi,

You can download the instruction manual in PDF format by clicking this link.

Adobe PDF Reader is required to view this manual. Download Adobe Reader

Hope this helps. Kindly let me know if you have any difficulty in downloading the manual.
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