Canon 450 Dpi

[jackbauer]

i just realised after 2 years that my canon 450D produces picts at a lousey 72dpi, rather than 300!! how do i get it to take and save picts at 300dpi?

i understand that the Nikon D40x does it very well.

btw i've tried it at saving as jpegs and raw.

 

[Thmaga]

Dpi, is a term used for printing. A camera cannot produce images at a certain DPI because dpi merely instructs the printer how many of the pixels it should print per inch.

Its likely that your software is setting the files at the wrong value, 72 is used for viewing on-screen.

In Photoshop the dpi can be changed under image size, untick resample image and enter 300 in the resolution box, taking note that its set to pixels/inch.

 

[leeboy22001]

I just shoot in RAW and use DPP to convert to 300 dpi jpegs.

 

[jackbauer]

but if i use photoshop and ask it to save file at 300dpi, am i not guilty of upscaling a pict?

 

[TinaC]

I think you will find that 72 dpi is the viewing resolution on screen. The print resolution will be different and is set in your imaging software.

I have Elements set to 72 for on screen and 300dpi for output to printer.

Hope this helps

 

[Thmaga]

if you untick resample image, all it will do is change the number attached to the file from 72 to 300 , the pixels wont change

 

[jackbauer]

if you untick resample image, all it will do is change the number attached to the file from 72 to 300 , the pixels wont change

where is the resample image option?

 

[jackbauer]

but if i use photoshop and ask it to save file at 300dpi, am i not guilty of upscaling a pict?

so the 72dpi thats attached to the file is just used for printing purposes, so if i were to have it printed it will print at 72dpi?

 

[feriso]

No, you still have the same number of pixels in your picture, it just tells the printer how many of them to print per inch

 

[jackbauer]

also if it is just a number why does Pshop add a whole megabyte to the file size? when i change it from 72 to 300

 

[Jakska]

so the 72dpi thats attached to the file is just used for printing purposes, so if i were to have it printed it will print at 72dpi?

Basically yeah. If your file is 72 dpi, then your print will have 72 dots per inch. That kind of print resolution is great if you want to print things that are going to be viewed from afar. Lowering the dpi is a good way of really enlarging things for print, for example for billboards or bill posters, etc. If you want something to be viewed close (arms length or closer) then you want as much detail as possible so stick to 300+ dpi. Ignore the numbers unless you're going to print, on-screen the dpi figures don't mean anything at all.

 

[Thmaga]

also if it is just a number why does Pshop add a whole megabyte to the file size? when i change it from 72 to 300

it shouldn't change anything except the dpi, if the file size is changing, then its upscaling the image, what photoshop version do you have?

 

[mercmanuk]

Just updated DPP and it is preset to 350 dpi is this better or worse than 300, or is 300 about right

Merc

 

[thelamont]

i just realised after 2 years that my canon 450D produces picts at a lousey 72dpi, rather than 300!! how do i get it to take and save picts at 300dpi?

i understand that the Nikon D40x does it very well.

btw i've tried it at saving as jpegs and raw.

Hi ... I think you will find that if you save in RAW with a 450D the resulting pic will be 4272 x 2848 pixels ... now that don't sound too lousey to me.

DPI is the print resolution ... 72dpi = low quality ... 300 dpi = high quality.

 

[existent]

if you untick resample image, all it will do is change the number attached to the file from 72 to 300 , the pixels wont change

I always thought dpi and image size determined how big you can print at what quality..

for example if you can print a 12mb file at 18x12 at 300dpi, then your dpi will be lower for a 24x16 print unless you upscale...

 

[jackbauer]

it shouldn't change anything except the dpi, if the file size is changing, then its upscaling the image, what photoshop version do you have?

Photoshop CS5

 

[Roy C]

Just updated DPP and it is preset to 350 dpi is this better or worse than 300, or is 300 about right

Merc

As many have explained Merc, the dpi is only relevant at print time so you can have any figure you like 72, 200, 300 or even 1000 is does not matter, the number of pixels, file size and image quality will be unaffected.

 

[jackbauer]

As many have explained Merc, the dpi is only relevant at print time so you can have any figure you like 72, 200, 300 or even 1000 is does not matter, the number of pixels, file size and image quality will be unaffected.

not true, all i did was change the dpi of one image from 72 to 300, and it added an extra MByte to the file!

also "...if you untick resample image" <<did that too

 

[Roy C]

not true, all i did was change the dpi of one image from 72 to 300, and it added an extra MByte to the file!

also "...if you untick resample image" <<did that too

That is because you up rezed and added pixels - keep the same pixels size and just change the dpi to whatever you want - the file size will not change.
As an example if your image is, say, 4000 x 2000 pixels and 72 dpi - just change the dpi to whatever you want (try 1000 dpi) and make sure that your pixel size is still 4000 x 2000, the resulting file size will not change.

 

[jackbauer]

That is because you up rezed and added pixels - keep the same pixels size and just change the dpi to whatever you want - the file size will not change.
As an example if your image is, say, 4000 x 2000 pixels and 72 dpi - just change the dpi to whatever you want (try 1000 dpi) and make sure that your pixel size is still 4000 x 2000, the resulting file size will not change.

i have!!! the pixel size remains the same but the file size increases by 1mb!

 

[Roy C]

i have!!! the pixel size remains the same but the file size increases by 1mb!

You must be doing something wrong as changing the dpi without altering the pixel dimensions will not change the file size (assuming, of course that you also do not change, say, the jpeg quality setting).

I have only had CS5 for a week so I just tried it to see if it was any weird CS5 thing. I took a 1000 x 750 72 dpi pic which was 130 KB and changed the dpi to 1000 (keeping the pixels at 1000 x 750). the resultant file was still 130 KB. You are most certainly doing something wrong.

 

[POAH]

sounds normal - are you saving at quality 12?

i have!!! the pixel size remains the same but the file size increases by 1mb!