PPI is not DPI

[NobleValerian]

One cannot have an image in an application without effective resolution. It is impossible.

 

And one can have an image with a high effective resolution and have a poor print if the effective resolution exceeds the ability of the output device. Pixels will be tossed out in that case.

Well, that nonsense is just really good bait, I guess.  It is only "Effective Resolution" if the resolution change is a result of scaling, so you know if you're going to have enough pixel data for your desired result.  A 300 PPI image at 100% does not have an Effective Resolution, it has an Actual Resolution, because it has not been scaled.

 

For the sake of a proper argument, though, we should probably say that you're right.  Only for the sake of argument, because the point would be that effective resolution is about how much pixel data will fit into a set amount of space, not how many dots.  And the conversation is about PPI vs DPI.  Your effective resolution is PPI, not DPI, because how many pixels of data are held within that space has little to do with how many dots will be used to get your final result.  And just about every link out there explaining the difference between actual and effective will call it PPI, because until you print, your document is made of pixels, not dots.

[MikeW]

Even if an image is placed 1:1 in accordance to the dimensions = pixels, an image has an effective resolution. I think it is rare, in my work anyway, to ever have a 1:1 effective resolution. But even so, it is still effective resolution.

 

That effective resolution even at 1:1 is not what the resolution at print, either.

 

As I have said in reply to many of your and others' posts, I completely agree about the term swap. I would prefer it. And like Serif has replied to you and some others, they will revisit the use of terms for this.

 

Everything else we are doing is bantering about what those terms mean in the context of actual and abstract notions.

[Sharkey]

A little knowledge is a dangerous thing but too much knowledge can also be so.

 

Up until now my knowledge was based on the image manipulation software having PPI in the file title and my printer (and printing companies) I have used, having a DPI which I am asked to select.

 

Having read this and other contradictory postings I now know I know just enough to edit and print my photographs in a manner that is comprehensible to me - the rest is from my perspective mostly irrelevant.

 

Rasters/Vectors/effective resolutions etc. I know not what they are and in my ignorance, I will no doubt remain.

 

My original contribution (if it was a contribution) was to simply state the I found the AP usage of DPI confusing and would like it changed. Easy really. Why do I need a 'Doctorate' in digital imaging etc. to back my contribution up? I do not.

 

My initial confusion no longer exists because I have decided that although I think the usage is wrong I can adapt to its existence faster than the software writers.

 

Regards    Sharkey

[R C-R]

Up until now my knowledge was based on the image manipulation software having PPI in the file title and my printer (and printing companies) I have used, having a DPI which I am asked to select.

Just curious, but what is the name of the image manipulation software you use that has PPI appearing in file titles?

[Sharkey]

Just curious, but what is the name of the image manipulation software you use that has PPI appearing in file titles?

 

Is this continuous 'Nit Picking' really necessary?

 

OK. Not in the file title - in the file description is probably more accurate.

 

Lucky I do not write software for general public use :lol:

 

I used to use Adobe Raw Reader and a file description was always at the bottom of an image opened. You could change the parameters of the image to what you wanted in preferences as I recall. I think my default choice was RGB 1998,600PPI,16BIT or there abouts.

 

I will try in future to be more accurate but I cannot guarantee it. I would try harder if I was being paid to be that accurate but luckily I have not had to be that committed to earn crust for some time. Retired early. 

 

Regards.   Sharkey