resolution

Djurchicprelude · Aug 17, 2005

so i took some digital pics that are 3072 x 2304 and am confused about something called resolution, i want to get some of these pics printed but someone told me i need a resolution of 300 or something. how do i find out what the resolution of these pics are? if its any easyer for you guys could u tell me what what sizes i can get it printed with it still being nice and crisp? thanks and sorry, i know its probably a total noob question. im just getting into photography but loving it. thanks again

Meysha · Aug 17, 2005

You'll need some software like photoshop or gimp to change the resolution.

What you have to be careful of though is the file size after you change it. When you change the resolution from 72dpi or whatever it is probably set to atm to 300 dpi (dots per inch) then your picture will get bigger (ie it'll go from 20MB to something like 400MB). So you then have to physically change the height and width of the picture so that it's roughly the same MB size as before.

So with that size you mentioned you could get something like a 7 x 10 or some weird shape slightly biggger. You can of course make a bigger print, but then you start adding in pixels and that's when you get loss of quality.

Big Mike · Aug 17, 2005

If you image is 3072 x 2304 pixels, that is your image size. Your resolution is the number of pixels per inch (PPI). The default is usually 72, which is good for viewing on a computer. So that image at 72 PPI would be 42" x 32" on a computer at 100%...very big.

If you changed the resolution to 300 PPI you would have an image about 10" x 7".

Typically printing is done at 300 dots per inch (DPI)...so the size at 300 PPI is the same size when printed at 300 DPI.

It is possible to change the image size, to make it bigger but this requires the software to do some interpretation...the bigger you go, the more interpretation, the worse the image will look.

Djurchicprelude · Aug 17, 2005

ok i get that, but how do i change the resolution to 300? is that something i gotta do on my digital camera? or on the computer? or can i just put the pic on a cd and take it to the camera shop and they will change it? i want to orint it out kinda big but dont want the pic to look like ****, want it all nice and crisp

JohnMF · Aug 17, 2005

if you just want to get it developed i wouldnt worry about the resolution, just leave it at what your digital camera has made it by default. take it to your local deveopers or online developers and tell them what size you want them. just bumping up the resolution to 300dpi wont make the quality any better than it already is, you'll just end up with a massive file!

For books and magazines pictures are usually scanned at 300dpi+ and cropped to the required size.

fadingaway1986 · Aug 18, 2005

If it helps to know,

My 300D takes them at 180DPI... So... I would assume 300 isn't needed.

Big Mike · Aug 18, 2005

300 DPI is the PRINTER setting...it has nothing to do with the camera.

The resolution of the digital file is PPI pixels per inch...and if you are sending the file to be printed...then yes, it does not matter very much...they will do whatever they need to do...to get a good print for you.

Another thing you need to be aware of is the size of the file (in pixels) compared to the size of print you want. If the ratio is not the same...they will have to crop the image to get the right size...and you may not like the arbitrary crop they make. So, it's best to make the crop yourself. For example, if you want a 5x7 make the file 1500x2100 (or at least that ratio.)

fadingaway1986 · Aug 18, 2005

There was no need to yell.

And you are wrong, the printer will not do whatever is needed to get you a good print. They couldnt give a **** about whether or not your print is good. If your file wasn't good enough - thats your problem.

Big Mike · Aug 18, 2005

Sorry, I didn't mean to yell...just emphasize my point. It seems that most people get it wrong. Including, a lot of documentation, web sites, articles and stores.

A 20D is a better camera than a 300D and the files come off at 72 PPI.

What I meant to say is that 'if you file is good enough', you can send it for printing at 72 PPI or 180 PPI or what ever. Their software will do what ever it does to make the print. If they print it at 100 DPI...and it looks like crap...well then don't pay for it.

If however you are printing the file yourself...that's when you should make sure to set the PPI high enough. 300 is usually the safe number but some might use something like 240 PPI.

Vmann · Aug 18, 2005

fadingaway1986 said:
And you are wrong, the printer will not do whatever is needed to get you a good print. They couldnt give a **** about whether or not your print is good. If your file wasn't good enough - thats your problem.

I don't know what lab you use but my labs will usaully go out of there way... to the best of there ability and time to create what they think it is you want. There reputation and future business is depending on it. Some labs don't even like when people try to resize because there programs or process dont match the quality the lab can achieve. It all depends on what labs you use. Just pick a good one... trial/error. Also if they look like junk as a result of poor printing not poor photography don't pay for them.

If you want to print these on a home printer then resizing is going to be more of a issue but even then some home and photo printers can produce decent prints by such large files because your going to have to shrink the print to "fit the page". Not the best way but depending on your printer will usaully work. If not there are plenty of tutorials online for photoshop or like programs.

fadingaway1986 · Aug 19, 2005

I am not speaking of using a lab. I work in one. Basically if someone brings in a file, and it's not good enough, that's their problem, not ours.

Also our machines are automated. I had a lady almost refuse to pay for her 50 or so photos, because she had taken them on a camera phone and they looked absolutely TERRIBLE. Basically I made her pay, because that is her fault, not ours. Anyone who knows anything about taking a photo knows those cameras are worthless.

Meysha · Aug 19, 2005

If you're going to be printing the file at home - I find that the software you use to send the photo to the printer is very very important. And depending on what you use the picture can be of crap or great quality - even if it's the same file. So don't use some crappy cheap program.

ksmattfish · Aug 19, 2005

Djurchicprelude said:
so i took some digital pics that are 3072 x 2304 and am confused about something called resolution,

Your photo's resolution is 3072 pixels by 2304 pixels. These are the dots that make up the image.

DPI and PPI stand for dots per inch and points per inch. DPI and PPI don't change resolution, they just measure how far the dots are spread out.

If you set it to 300 dpi/ppi then your photo will be set up to be 10.24" x 7.68" ( 3074 divided by 300 = 10.24, and 2304 divided by 300 = 7.68 ).

If you set it to 200 dpi/ppi it would be the same resolution, but set up to be viewed/printed 15.37" x 11.52" ( 3074 / 200 = 15.37, etc... ).

How high dpi/ppi is required to make a good photo depends on a lot of things, including the viewer's opinion. Over 200 dpi/ppi usually looks pretty good. You'll just have to get some big prints made to see if you think they are good enough. My digital camera files are 3504 x 2336, and I was very surprised at how good the 18"x12" prints look ( that's about 200 dpi ).

Just take the full res file ( 3072 x 2304 ) to the lab, and tell them how big you want it printed. If the dpi/ppi of the file doesn't match the print size you have requested, and the lab can't deal with it, then find another lab, because they suck.