Rebel XT DPI

[Michaelmjc]

Does anyone know what the DPI is for the Rebel XT?

Thanks,
Mike

[tim]

We really need a sticky to explain resolution to people. Try reading this (http://photography-on-the.net/forum/showthread.php?t=71802). DPI is irrelevant in 99% of situations.

[Michaelmjc]

The only reason why I ask is, My neighbor works at a printing press. He said he could print off some nice size prints but he needs to know the dpi. I'm not asking what DPI is, just asking what the DPI is on the XT.

[Jim_T]

Does anyone know what the DPI is for the Rebel XT?

Thanks,
Mike

The DPI is whatever you want to make it :)

Asking the DPI of a camera is kind of like asking the MPH of a car..

Edit...... The formula for dots per inch is dots divided by inches

If you have 1000 dots and you spread them across 10 inches, you have 1000 / 10 = 100 DPI

That's it... Go back and ask the publisher how BIG he'll be printing the images.. Then just take the total pixels and divide by inches.. You can then tell him how many DPI..

[Michaelmjc]

The DPI is whatever you want to make it :)

Asking the DPI of a camera is kind of like asking the MPH of a car..
Ok, what is the max DPI of it then?

[Jim_T]

We're doubling here :)

If you go back and read my edit.. It should be clear..

Dots per inch = dots divided by inches..

If you don't know the inches you plan on printing, you CAN'T solve DPI.


It's kind of like saying "How far will I go if I'm travelling in my car at 30MPH"

In this case, without TIME, there is NO way to answer the question..

[lostdoggy]

A guess: 240 to 300 from RAW to TIFF 8bit
Most printer at home at least needs 140dpi for a 5x7
But like Jim said its what you make it to be
You can find out how many dpi from loading it in PS CS browser look in the lower lefthand side you EXIF file will give the info you are asking.
Again if you are shooting RAW how you process the file will determine the DPI.

[tim]

Ok, what is the max DPI of it then?

Well, say it's 3000 dots (pixels) and you print it 0.1 inches wide. That makes 30,000 dots per inch. If you print it 1 inch wide that's 3000 dots per inch. etc.

[Michaelmjc]

Ahhh... makes a lot more sence now. Thanks for clearing it up, those analagies (think thats spelled wrong) helped a lot ;)

[lostdoggy]

Try this:
http://www.luminous-landscape.com/tutorials/understanding-series/und_resolution.shtml

[lostdoggy]

Here is another:
http://www.luminous-landscape.com/tutorials/understanding-series/res-demyst.shtml

[Jackal]

Alright so let me get this straight. As I am also confused on this (too used to dark room printing)

If my printer specs are:
-Up to 4,800 x 1,200 optimized color dpi output on premium photo paper

Is this the correct process in printing a 6x4 size print?

-Open full res picture in PS
-Goto image size, under document pick 6 inches x 4 inches and put 300 for pixels/inch?
-It will shrink it down and I goto print and print it.

Does that pixels/inch have anything to do with printing or am I way off?

[Edit] Heh, ok I had resample image check so it wasn't automatically changing the pixels/inch.

If I take one of my pictures and make the document size 6x4 the pixels/inch turns into 576. How do I know if this is ok for the printer?

[lostdoggy]

I'm not an expert on this but, you only need about 72dpi on the monitor to view and it will look great but in order to print it on a printer you'll need at lease 150dpi for a 5x7 but most onsumer level printer tops out around 180dpi. What see in most advertised printer rating is interpolated. Mean that adjacent dots are being duplicate to fill in the gaps. Check the links above. Good info on the matter.

[Bob_A]

I believe that for a typical "hand held" viewing distance you need 300 dpi for high quality prints (300 x 300 dpi is also the max resolution spec for my Selphy CP600 4x6 proof printer). Given this, the 20D can make an exceptional 8x10 (7.8x11.7) print that will closely match the result from a film camera without any special software.

However ...

If you are making very large prints you are not typically viewing them close up. So, the size of the print that you can make also depends on how far away the person viewing it is going to be. You could produce a great billboard sized image if it is being viewed from a distance far enough away.

Also, you can purchase software such as Genuine Fractals that can interpolate to make very high quality large prints from lower MP cameras.

So, how big do you want your image to be?


Bob

[robertwgross]

If my printer specs are:
-Up to 4,800 x 1,200 optimized color dpi output on premium photo paper

That is a bit of printer company spec-manship.

Most inkjet printers spray a number of different colors of ink together to produce a single dot on the paper. If you need to get more than 300 DPI aggregate, then something is wrong.

---Bob Gross---