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Ben Rum - 16 Mar 2005 12:13 GMT

I'm a new user of a Canon EOS 300D, I used to download directly from the
Camera using the Canon FileViewer utility, and do so at 300 pixels/inch. (at
USB 1.1 which is way too slow)

I have bought a USB 2.0 CF reader, and it seems to download at 180 pixels /
inch. The reader has no software, it's just an external drive.

How can I increase this?? Or do I need to?

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Alan Browne - 16 Mar 2005 15:41 GMT

> How can I increase this?? Or do I need to?

It's arbitrary, don't worry. Set the print dpi as you need it in PS and
get on with it.

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G.T. - 16 Mar 2005 17:52 GMT

> I'm a new user of a Canon EOS 300D, I used to download directly from the
> Camera using the Canon FileViewer utility, and do so at 300 pixels/inch. (at
[quoted text clipped - 4 lines]
>
> How can I increase this?? Or do I need to?

Good idea in getting the CF reader. PPI can be changed in most any image
manipulation program and is only needed when you go to print.

Greg

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Ben Rum - 16 Mar 2005 18:31 GMT

> Good idea in getting the CF reader. PPI can be changed in most any image
> manipulation program and is only needed when you go to print.
>
> Greg

Thanks, can I expand a little on this then? I'll have to do some RTFM'ing I
think..

If I have a shot that I save to 72 pixels / inch, and the same shot save to
900 pixels / inch. I'm not really going to get any more detail, just a
bigger file right? In which case, I'm not sure I'm seeing any advantage in
either option, as the photo is captured with a defined level of detail to
begin with.

So if I print both files (one at 72ppi and one at 900ppi) at, 10x8, I'm
really going to get the same detail in the print arent I? Both images are
essentially the same thing only one is just an "inflated" version of the
other.

Thanks, Ben.

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G.T. - 16 Mar 2005 20:06 GMT

Remember the last letter of ppi is inch. E.g., a 6MP file at 72PPI
will not fit on an 8x10 and the same 6MP file at 900PPI will be much
smaller than 8x10. Vice versa, if you want to print at 900PPI (which
you probably realize is overkill) on an 8x10 you're going to need a lot
of pixels, i.e. a much larger file size.

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Jeremy Nixon - 16 Mar 2005 20:49 GMT

> If I have a shot that I save to 72 pixels / inch, and the same shot save to
> 900 pixels / inch. I'm not really going to get any more detail, just a
> bigger file right?

You're going to get exactly the same file, the only difference being that
one will say "72 pixels per inch" and the other will say "900 pixels per
inch". The files will be the same size and the picture material will be
exactly identical. The "pixels per inch" is an arbitrary number that has
no meaning whatsoever until you print the file, at which point it is
determined by the picture size in pixels versus the print size.

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Jeremy | jeremy@exit109.com

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David H. Lipman - 16 Mar 2005 18:57 GMT

From: "Ben Rum" <bundyrum75@yahoo.com>

| I'm a new user of a Canon EOS 300D, I used to download directly from the
| Camera using the Canon FileViewer utility, and do so at 300 pixels/inch. (at
[quoted text clipped - 4 lines]
|
| How can I increase this?? Or do I need to?

If you are using a USB v2.0 CF Card Reader connected to a USB v2.0 port, then you will have
a drive letter such as "G:" on your computer and you would be copying files at xxMB/sec not
pixels/inch.

If your hard disk is "C:" and the Card Reader is "G:", copy the folders from the "G:" drive
to the "C:" drive and then edit your RAW and/or JPEGs from the POV of your "C:" drive. The
"C:" drive is the faster of the two drives.

When you are satisfied, you can delete all files/folders on the "G:" drive, reformat the
"G:" drive on the computer or reformat the CF card in your camera.

Signature

Dave

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Skip M - 17 Mar 2005 04:58 GMT

> I'm a new user of a Canon EOS 300D, I used to download directly from the
> Camera using the Canon FileViewer utility, and do so at 300 pixels/inch.
[quoted text clipped - 6 lines]
>
> How can I increase this?? Or do I need to?

Check your actual image size. The pixel dimensions will be the same, but
the inch/mm dimensions will be different. 180dpi at 11x17 approx is the
size those little puppies come out of your camera, Canon FileViewer utility
arbitrarily upsizes to 300dpi on an 8x12. On my 20D it's 350dpi for an 8x12
vs. 292dpi from the card reader, where the image dimensions are 2336p x
3504p or 8.185344 mp, the resolution of my camera. My D30, a 3mp camera,
came up, at 8x12 and 180dpi, 1440x2160, or 3.110mp. I'll bet if you look at
the dimensions of your image, it'll equal 6mp, or thereabouts, no matter
what the dpi says.
You can resize to any dimensions, with in reason, that you want.

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Skip Middleton
http://www.shadowcatcherimagery.com

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Dr. Joel M. Hoffman - 22 Mar 2005 01:56 GMT

>I'm a new user of a Canon EOS 300D, I used to download directly from the
>Camera using the Canon FileViewer utility, and do so at 300 pixels/inch. (at
[quoted text clipped - 4 lines]
>
>How can I increase this?? Or do I need to?

Dots per inch (DPI) is meaningless until you print (or display) the
file. Until then, all you care about it the number of dots in the
file.

-Joel

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Bob Niland - 22 Mar 2005 02:07 GMT

>> ... new user of a Canon EOS 300D, ... and it seems to
>> download at 180 pixels / inch. How can I increase this??

Unless there's some hidden camera menu or firmware hack,
you can't. I surmise that Canon printers have native
print resolutions that are integer multiples or fractions
of 180 dpi (vs., say, 150 for HP), and that Canon has
hard-coded the image dpi for their own printers. What a
surprise, not - and a bit of a nuisance, as I'd much
prefer 300 dpi.

This seems to be a function of image storage in the cam,
and is independent of how you extract the images. I also
use a USB 2.0 CF reader. The reader has nothing to do
with the dpi.

> Or do I need to?

> Dr. Joel M. Hoffman <joel@exc.com> wrote:
> Dots per inch (DPI) is meaningless until you print (or
> display) the file. Until then, all you care about it the
> number of dots in the file.

True. If you have to edit/adjust/resave the image anyway,
any decent image editor (e.g. PhotoShop) will allow you to
re-declare the image res without actually re-scaling it.
But don't do this just as an open-redeclare-resave op,
because doing so in .jpg always entails more losses.

There may exist applets that just allow hacking the res
declaration in JPEGs, and can do so with no image losses.

Of course, you can also shoot raw and resave in some other
lossless format such as TIFF.

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