How are you printing?
What resolution does the printer want?
Usually, printing is done at something like 300ppi. At this resolution a 2×2 pixel dot would be 0.169mm. Good enough?
I am printing at 300ppi. I need to be able to calculate this, as I have 11 specks total, ranging from .16 to 2.25 MM. Can you tell me how you derived that it would be 2×2 pixels?
Thanks for your help!
Can’t you just do a fixel size marquee and type in the numbers?
Sure, once I know what the dimensions are. I was asking him how he derived that .16 mm would be equivalent to 2×2. How do I translate MM to Pixels?
It would be better to use InDesign, or QXP, or Illustrator and make these vector circles where you can simply type in the dimensions.
BTW:
MM times File resolution (expressed in Pixels/MM) = Pixels
Pixels/Inch times 25.4 = Pixels/MM
I was asking him how he derived that .16 mm would be equivalent to 2×2. How do I translate MM to Pixels?
It is something called math.
At 300 PPI, 1 pixel = 0.09mm, or 0.004 inch. These numbers are rounded.
Viol8ion,
You don’t have to be sarcastic. All I was asking for is the conversion from mm to pixels. Thanks for providing it, but you didn’t have to be so rude.
Mommy, he yelled at me!!!
I guess Viol8ion gave you the answer.
At 300ppi, each pixel is 0.084667mm. So you can make dots that are any multiple of this.
Whilst not being sarcastic, I appreciate that maths is not everyone’s strong point and something that is blindingly obvious to me, may be a mystery to someone just a smart. So, do come back if you need more [help that is, not sarcasm …].
BTW, Viol8ion
At 300 PPI, 1 pixel = 0.09mm, or 0.004 inch. These numbers are rounded
Incorrect. Rounding 0.084667 to 2 decimal places gives 0.08. Over here, we call it maths [as it is plural].
π
Incorrect. Rounding 0.084667 to 2 decimal places gives 0.08. Over here, we call it maths [as it is plural].
π
Heheh! Call me lazy for not adding the ‘s’.
I must disagree with your rounding, .084 would round to .08, yes. But the number is not .084, as the .0846 rounds to .085 which rounds to .09, at least in the maths I was taught. But, then that was many years ago, and who knows what has transpired in education since the dark ages.
"Over here, we call it maths [as it is plural]."
Between that usage, and using a collective verb for a company or group, such as: "Adobe are introducing a new application" UK’ers give themselves away every time!
π
Phos
Let alone references to colour and a PS tool called a rubber … π
Between that usage, and using a collective verb for a company or group, such as: "Adobe are introducing a new application" UK’ers give themselves away every time!
Isn’t that why we kicked them out of the country during the revolutions? Revolutions is plurals, isn’t it?
must disagree with your rounding, .084 would round to .08, yes. But the number is not .084, as the .0846 rounds to .085 which rounds to .09, at least in the maths I was taught. But, then that was many years ago, and who knows what has transpired in education since the dark ages.
I was educated in the Stone Age, according to my 16 year old daughter. Back then, the rounding mechanism we were taught was to look one digit to the right of the last one in the result. So, in this case, I would first truncate to 0.84 and then round.
I will now waste hours searching for documentary evidence … [No I won’t – I have a life. :-)]
BTW, maths is the abbreviation for mathematics. Just like hols is short for holidays. I gotcha this time.
Back then, the rounding mechanism we were taught was to look one digit to the right of the last one in the result. So, in this case, I would first truncate to 0.84 and then round.
I think my method is more accurate! ;-p Anyway, either one is close enough for rock and roll. Especially since, printing at 300DPI, 2 pixes at .084 or .085 will be closer to .17 than it will to .16, no matter how you round!
[edit] fixing my maths
I think my method is more accurate
Well, maybe. Anyway, I am not at all sure that the OP’s plan makes a lot of sense. Will a conventional printer actually print dots of this size?
It all depends on the level of accuracy he demands. a 2×2 pixel dot will measure .168mm by your rounded computation, .17mm by mine, actually somewhere in between, so he will be SOL trying to print a .16mm dot at 300PPI. At a higher PPI, he can get closer, it all depends on the precision of the printer, as well as type of ink and paper, ink will bleed as paper is porous.
EW,
You have a further problem. Inevitably when you go to print there will be some dot-gain. That will make small black dots print larger than the image would suggest. (white dots would print smaller).
Although your printer will be able to give you a guide as to how much dot-gain their press on the specified media is likely to suffer, the figure won’t be accurate enough to rely on for sizing a dot of that size.
FWIW, I ascribe to the Colin method of rounding.
A "more accurately rounded" number seems like a bit of an oxymoron.
By carl’s method 4.44444444444449 would round to 4.5
And if accuracy is key, then using Photoshop pixels is not the answer, but a vector object which may be sized to an unattainable degree of accuracy, the limitation being the resoltion of the printer.
A "more accurately rounded" number seems like a bit of an oxymoron.
Welcome to our paradox! π
I think thatis exactly what we have been saying in a round-about way. There is not likely to be a cost effective way to print a highly accurate representation. It all will depend on the amount of variance that is allowable with these sizes. Is 10% deviation allowable? Then it is likely do-able. Do they require a 2% tolerance? Then not likely with a 300PPI press.
Some fact about rounding:
It is always assumed that the precision of a rounded number cannot be larger than 0.5 times the decimal position you have rounded to (so in this case, we round to the second decimal position, we get: 0.01 x 0.5 = 0.005
Now let us look at an example:
According to Viol, rounding 1.0848 by you method gives you 1.09, which has an innacuracy of 0.0052
Rounding by the other (proper) method, you get 1.08 which has an innacuracy of 0.0048
Trust the mathee <grin>
Trust the mathee <grin>
Cool! Math never was my strong suite in school. I was too busy drawing pictures of girl’s butts on the notebook paper.
I’d do it in Illustrator, where I can create with an accuracy down to 13 X 10-7 of an inch.
But then, I’m a little obsessive about such things.
Cool! Math never was my strong suite in school. I was too busy drawing pictures of girl’s butts on the notebook paper.
You too? Now there’s a coincidence. π
and the funny thing is, 30 years later and I am still doing it!
Me too, of course. But now I’ve got over the hangup that someone might seem them and think they are boys. π
And we are going to be out of here any moment!
I think you’d be MUCH better off using a vector-based tool such as illustrator if you need this level of accuracy.
Brian
I’m not so sure you would get better accuracy. Using vectors, you are leaving the rasterization to the computer (it must be rasterized to print). If you are printing to a 600 dpi printer, I would set PS at 600 ppi and thus be able to know where pixels will fall, exactly.
So, can the math(s) genius’s figure out what a dot is at 600 ppi? <g,d&r>
I’ll see Don’s question, and raise, ALL IN, with this:
Q: How many 0.16mm specks in a parsec?
A: 192 quintillion, 854 quadrillion, 875 trillion.
If you are printing to a 600 dpi printer, I would set PS at 600 ppi and thus be able to know where pixels will fall, exactly
That might work if you had a monochome printer, but a colour printer will print all dots at the specified DPI. So a six colour, 600DPI printer might only print black at 100DPI. Also, printers often have assymetric DPIs.
So, can the math(s) genius’s figure out what a dot is at 600 ppi?
Yes, they can. π
So, can the math(s) genius’s figure out what a dot is at 600 ppi?
1 inch divided by 600 pixels equals 1/600th of an inch (or 0.001667 inches)
I’m not so sure you would get better accuracy. Using vectors, you are leaving the rasterization to the computer (it must be rasterized to print). If you are printing to a 600 dpi printer, I would set PS at 600 ppi and thus be able to know where pixels will fall, exactly.
While what you say is essentially true, this only applies to black and white printers receiving bitmap mode images. As soon as your send a greyscale or a colour image, the RIP (not the computer) steps in anyway.
Also, the PS file becomes less precise as soon as you change print resolution. Having the printer’s RIP rasterize the vector data is the more precise method.
If going out to a film rip your talking more like 2400dpi for accuracy. So that would be the limitation of using vectors.
Bear in mind that you can only fit 152,064,000 printer dots @2400dpi in a mile.
152,064,000 Printer dots? How many ink cartridges is that a what ever pico-liter/dot?
That’s a "whole slew of sauce" as we like to say in the printing biz.
Which leads to the well know axiom, "I’d walk a mile for a slew of sauce"
Kewpie doll to Renee (and Colin by default).
You can’t round twice, i.e., 0.849 becomes 0.85, which becomes 0.9. That would mean it REALLY becomes 1.0. Don werk lak that. Round once. When we round, we look at the single digit next to the number we’re rounding. Question: Is .04 less than or greater than 0.05? Less than. Thus, round down.
Sorry Carl.
But Colin, if we say "maths" here, it may incorrectly associate us with a particular socioeconomic class; and not a flattering one.
Thanks Tony. The way you explain it, it seems almost obvious.
it may incorrectly associate us with a particular socioeconomic class; and not a flattering one
Have to say you’ve stumped me here. I have no idea what you are alluding to. I am curious.
It’s a local thing Colin. It would basically mean that you speak in a "less than educated" fashion. It’d be like saying "I axed my teacher…" Maybe like a Cockney accent might be perceived by other parts of your country? That’s a guess.
I had better shut up now.
Nahhhh…."mathsUK"Βas a shortened term compared to "mathUS"Βis just a product of local colloquial familiarity. You’s, You’ins, Ya’ll, and many other similar regional pronunciations and variations..they’re all linguistic territorial identifier flags.
I find "Maths" as spoken and written to be rather quaintly provincial, but not an undereducated way of contrcating the word and concept.
It’s on my shortlist of EuroYokelSpeak that doesn’t raise my hackles.
:);):);)
Well I guess that settles it then.
It’s on my shortlist of EuroYokelSpeak that doesn’t raise my hackles
I have to ask: what does raise ’em?
Using "momentarily" correctly?
Spelling "aluminium" correctly?
π π
Aluminium, dangit, aluminium. It’s just too vocally busy.
Hey mang, wanna buy a custom Neonium sign for your basement billiards room?
Again..I got cocktails, and good breakfast confab in the Lounge. All ya gotta do is ask for ’em and, before too long, I’ll show up.
;):)
Aluminum was a typo made in 1906.
Most other elements end in "ium" [helium, magnesium …]. Ask Tom Lehrer.
If I was ever so fortunate to have had an elbow-to-elbow audience with Tom Lehrer, he and I would have a hilarious improv argument centering on the absurdity of the importance of the difference between aluminum and aluminium.
And we would have rallied together to bring the Isotopes back from Albuquerque.
And then we’d’ve riffed, at 5:59 am, about who has the best late night burgers.
Is TL still alive and kicking? My recordings of his stuff date back to 50s and 60s.
Ya know, Colin, that’s a good question.
Isn’t there some "DeadOrAlive.com" -type of website that could answer this question for us?
