Page 1 of 1

Photoprinter Resolutions

PostPosted: Tue Oct 03, 2006 11:32 pm
by MattyO
I have been searching for this answer for a while and havn't really come up with anything.

What resolution do photoprinters at harvey norman, and maybe other places print at?

I am just wondering how far my 6mp will go, especially when cropping pictures?

Sorry if this has been answered elsewhere

-Matt

PostPosted: Tue Oct 03, 2006 11:35 pm
by Ady
I think most high quality prints are done at no more than 300DPI. You can go lower than that and still have decent quality, but I don't think it would be worth pushing it below 200DPI. You should be pretty safe if you work things based on that.

PostPosted: Tue Oct 03, 2006 11:43 pm
by MattyO
Sorry, one last question. Is the 200 dots per square inch? or 200 dots along one side? ie 40,000 dots per square inch?

PostPosted: Tue Oct 03, 2006 11:50 pm
by Ady
Hang on, i'll just go count them. brb











Okay I was just joking. :lol: :lol:

I guess it's just dots per square inch. :)

An easy way to see how big you could print is just by opening your image in photo shop and in the image size dialog box, under document size change it to somewhere between 200-300dpi from 72dpi and it will tell you how big the picture is in cm, mm, etc. Just make sure you untick resample image before you change the DPI. Hope that helps.

PostPosted: Wed Oct 04, 2006 12:51 am
by sirhc55
Yup - dots per square inch. Dots per inch relates to the lpi (lines per inch) as applied in litho printing - in this case 300dpi is, in fact, 150lpi. Most magazines print between 150 and 175lpi, whilst newspapers are anything from 60 to 96. The reason that newspapers have a lower dpi (or lpi) is due to the absorbency of the paper and the spread of ink.

PostPosted: Wed Oct 04, 2006 8:21 am
by Aussie Dave
If they have a website, they usually state what DPI resolution they're printing at. I think it all comes down to what printer the lab is using. Some places print at 200 and some at 300.

As sirch said, it's Dots Per Inch.

An easy way to calculate what size your image needs to be, use this formula:

(no of inches) x (required dpi resolution)

eg. 8"x12" pic @ 300dpi would be:

8 x 300 = 2400 pixels
12 x 300 = 3600 pixels

Hence, you'd need to resize your image to 3600 x 2400 pixels (which from a D70 isn't that much of a stretch. Of course, if you were printing at 200dpi, it would be 2400 x 1600 pixels, which would mean you'd actually need to downsize your original file.

As long as the photo is quite sharp to begin with, most people seem to be able to print as large as 30" x 20" without any problem. Suffice to say, at this size, you're not meant to stand with your nose against the print on the wall to view it.....as it's not going to look like a 6x4 print. Remember, you're actually digitally adding pixels to the image that weren't really there, when upsizing an image :wink:

Hope this is helpful... :)

PostPosted: Wed Oct 04, 2006 11:59 am
by MattyO
Thank you people.

That has really helped. With printing an image, is there an acceptable amount that you can stretch an image before it starts to lose visual quality? Or should we strive to always stick within our pixel limitations

PostPosted: Wed Oct 04, 2006 2:46 pm
by Aussie Dave
MattyO wrote:Thank you people.

That has really helped. With printing an image, is there an acceptable amount that you can stretch an image before it starts to lose visual quality? Or should we strive to always stick within our pixel limitations


How blue is the sky ? :lol:
Unfortunately, it all depends on the quality of the image you're working from. Some will look great if you enlarge them alot, some will not.

As someone suggested in a post the other day, you can always enlarge to a specific size (assuming you have a size in mind), then take a 6"x4" crop from it and go get it printed to see what it looks like. You could perhaps take a few different crops from varying parts of the image. This will give you an idea on how it will look and it's not going to cost you a fortune, should you be disappointed.

If it looks good, get it printed full-size. If not, resize to a smaller dimension and try again... :)

PostPosted: Wed Oct 04, 2006 7:22 pm
by Matt. K
180 dpi is more than enough for most applications. Try it and see.