Digital Camera Resolution Problem

Hiya folks,I'm new here.* Hoping the vast knowledge base within this forum can help me with a problem.* Perhaps understanding it is my problem.* Here it is.* I'm an old school printer.* Letter presses and offset.* Dont have a clue about digital presses which my world has been converting to.* Whenever I printed photos on those old presses we operated in terms of 'DPI'* Dots per Inch.* Printers still do today even with digital presses.* Between 300 & 600 DPI is adequate for good print press rendering up to 5x7. My problem is no matter what resolution photos are at going into my computer, there is no guarentee they will end up the same coming out.* Example.* I up loaded a photo from my digital camera to my computer.* The photo was taken at the highest resolution setting of an 8.2 camera.* Looked great on my computer screen.* When I sent it to a comercial printer the resolution was barely 150 dpi.* I checked the photo in my Photo Shop program and it showed it to be nealy 1200 dpi.* What happened?* I did have to convert the photo into a 'pdf' file but I was assured by the software people that nothing was lost in the conversion.* It seems this problem is intermittent because I have received other photos from other people at much lower resolution and they have printed well while other photos of much higher resolution become pixilated at relatively small printing size (3x4).* Am I doing something wrong with the camera in uploading to the computer or is it something with the computer I dont understand.* Hope someone here can help me out.* Thank you.

You have multiple question for multiple questions.

1) software used to automatically send files to a printing service, may reduce the resolution so it doesn't take all night on a slow dial-up connection.

2) JPG file format has many setting which will affect the image quality. This includes pixelation of the image, the high the compression the more pixelation you will see.

3) Check you cameras settings, most of the time the standard setting is good but for large enlargements you need a lossless file format like Nikon RAW, or TIF would work. Some small PS cameras don't have anything but JPG and then you pick the setting with the less compression like form my Nikon JPG fine. Just be aware the file size is much larger, Little in my old Olympus C-3030 a 3.3 mega pixel camera the TIF is 12 mega byte, not its JPG setting out put of 700K.

Thankyou for your response freygr. Not sure I understand completly. As to compression of files sent to the press in first part of your response that is never an issure. As I understand it an 'FTP' is used on their email and can handle any size file. I've sent files nearly a gigabyte in size. I'm not digital camera savy. I use an inexpensive kodak model that has 8 meg capability. I still use film and a pentax 'H' model SLR I purchased in Japan in 1962. I'm not aware of any of those file formats you mentioned. The Kodak digital camera has 'good' and 'best' type selections. I take the memory card out of the camera and put in the computer to upload. Any photos that are printed commercially are converted to a 'pdf' file which goes directly to the press. In todays digital commercial printing world the work has to be press ready. There is no 'pre-flight'. The job is 'untouched by human hands' as they say. All I know is somewhere between the camera, computer and press, resolution on 'some' of my photos have severe resolution drop. In printers language what begins as a 600 or 1200 DPI photo ends up less than 150 DPI. Since its intermittent I have to assume its something I'm doing.

PDF will store the image in binary mode inside postscript and it could be the PDF converter which incorporates the image that's causing the problem. What are you using to convert it?

The best thing to do in Photoshop is to set the resolution to 300 and then to set the size that you want for width and height. This will then correct the image for you using a decent tool, and allow you to get the exact dimensions for printing.

Once this is done then the PDF converter should work okay.

However, If your just prinint pictures I suggest you try and find out if the printers will accept TIFF or JPG files for printing then you have better control, unless your creating a new paper or magazine with photo's in, in which case PDF will be required.

Hope that helps

Roger

In addition to the above resolution/size conversion in Photoshop, make sure to check the "Bicubic" resampling box. This will completely re-render the image and keep the ppi at the same amount. I have printed at 48"x96" with files from my 6.1MP D50 with excellent results using this method. Any good photo lab will resample images for larger prints if they are pro level. I don't use any lab that doesn't and it prevents me from having to upload huge files to them.