Archived from groups: comp.periphs.printers (
More info?)
BF <bfor@adelphia.net> wrote:
>
>>
>> I think your going to have to reset your brain and discard what you are
>> currently thinking i.e. stop confusing yourself.
>>
>> Printers don't know anything about pixels. They just react to the data
>> stream feed them. Normally across the width of the paper the nozzle
>> spacing controls the print resolution and the stepping motor controls
>> the resolution down the length of the paper. My I860 has the color
>> nozzles spaced at 1200 dpi and the motor can step to 4800 dpi
>> resolution. Per Canon's manual the printer can place droplets pitched
>> as fine as 1/4800".
>>
>> It is software/firmware that takes the input data (pixels) and scales
>> that to fit within the output size at the printer's resolution.
>> Theoretically, the closer your data matches the printers somewhat fixed
>> output resolution the better/sharper the print results should be.
>>
>> Using your example if you are taking 4000 pixels of data and placing
>> them along the 10" length of the paper and the printer can step 4800
>> dpi, then 48,000/4000 = 12 drops of ink for each "pixel" of data. Across
>> the wide of the print the resolution is 19,200 droplet of ink and you
>> have 2400 "pixels" of data = 8 drops of ink per pixel of data. All the
>> scaling is handled by software/firmware.
>>
>> The bigger the input data the larger the output data stream is and the
>> time to process the data goes up.
>>
>> This is my take but other may think otherwise.
>>
>> Mickey
>
>Please click the link below. If I go to resize in P.S., unselect
>"resample image", set the size I want to print at 8X10, it shows it will
>be at 406.4 pixels per inch. If I do the same thing with print with
>preview and pick the size 8X10, photoShop is setting it at 406.4 PPI, I
>assume. This is where the confusion comes in. I understand that printers
>print in dots of ink per inch, but where does the 406.4 PPI come into
>play. It obviously does something because it determines the size the
>print is going to be. Sorry I am so thick but this sort of stuff bothers
>me until I understand it. Thanks for your patience.
>
>
http://paintedover.com/uploads/4/imagesize.jpg
Isn't this just telling you that the "document" would be 406.4 ppi if
"printed" on the screen? PhotoShop doesn't know, after all, how many
nozzles your printer has or its resolution capabilities.