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S2 and my impressions.

ptomsu

Workshop Member
Jürgen, the resolution of the scan varies between scanners. For instance most of my drum scans are supplied to me at 4,000 pixels/inch.

The important point is when finalising your print file and sizes you need to use 'Image Size' in Photoshop and set the resolution to 360 pixels/inch (or divisibles) before sending to the printer.

Keith
Thanks for that tip Keith! Will do this for the prints I deliver to my printer from now on.
 

jotloob

Subscriber Member
Jürgen, the resolution of the scan varies between scanners. For instance most of my drum scans are supplied to me at 4,000 pixels/inch.
The important point is when finalising your print file and sizes you need to use 'Image Size' in Photoshop and set the resolution to 360 pixels/inch (or divisibles) before sending to the printer.
Keith
Keith

When I do scans on my ATRIXSCAN F1 , I set the "printer resolution" to 360dpi . (I never used any different value) . Pressing the ctrl key on my keyboard then shows me in the same field the resulting scan resolution . In most cases , it is 2400ppi , for the scanwork I do and the negative sizes I scan . When scanning LF 4x5 negatives , the "printer resolution" is set to 1800ppi . The smaller the negative , the higher the scanner resolution . This is done by the scanner software , which checks the film size during initialization . I use SILVERFAST Ai studio .

I do not understand , why the professional LAB does set the "printer resolution" to 300dpi . I will give them a call today , and post the answer .

Jürgen
 

KeithL

Well-known member
Jürgen

I'm afraid you've completely lost me there!

Let me try to explain my own position again. I always scan or have third party scans made at the native resolution of the scanner. This varies between scanners (and film formats) but typically would be 4000 pixels inch for a 6x6 drumscan. When finalising my print files I resize them and save them at the optimum resolution for the printer, typically 360 pixels/inch for Epson printers. When using third party printing services I save the files at the optimum resolution for the third party printer, again this varies depending on the type of printer used.

A word of warning, like most things in life, the 'Image Size' dialog in Photoshop is easy enough to understand and use if you know how to use it, but if you don't then it's all too easy to misunderstand and misuse!

Of course the print output resolution is an entirely different matter and depends on the printer and paper/ink combination used. Typically I would print at 1440 dots/inch using Epson printers and fine art matte papers.

Hope this helps rather than confuses!

Keith
 

carstenw

Active member
It is not serious though. No matter the printing resolution set for the file, there is the same number of pixels, and the value is just a number in the header of the file, which you can change later to fit your printer. The only exception would be if the printer adjusts its scanning resolution to be a multiple of the desired print resolution, as the Atrixscan F1 seems to do. Then you might get a non-divisible resolution, and the final result would have to be interpolated to be printed. I don't know how a given scanner scans differently to get different dpi values. Does it step the motor differently?
 

KeithL

Well-known member
I should add that the reason that I finalise the print files when using third party services rather than leaving it to them is because all too many of the services haven't a bloody clue :angry:
 

jotloob

Subscriber Member
Jürgen
I'm afraid you've completely lost me there !
Keith
Keith

No I have not lost you there at all .
The words of confusion are , that I used "printing solution" , but did not mean printer solution as used by EPSON , 2880 or 1440 .
So I confused you and others . Hopefully not too much . Sorry .

So you help me please in getting the correct word for the 360dpi the scan has . What is the correct word for that 360dpi resolution .

Summary : I scan a 6x12 negative at a scanner resolution of 2400ppi .
I have choosen , that the scan shall have 360dpi (that in turn results in 2400ppi for the scanner) and print my image at a resolution of say 1440 or 2880 after reworking the image with PS .
 

KeithL

Well-known member
Keith
Summary : I scan a 6x12 negative at a scanner resolution of 2400ppi .
I have choosen , that the scan shall have 360dpi (that in turn results in 2400ppi for the scanner) and print my image at a resolution of say 1440 or 2880 after reworking the image with PS .
Jürgen

Sorry, but I'm still confused (this is no critisism of you).

I understand that you are scanning your negative at 2400 pixels/inch and that you are printing your image at 1440 or 2880 dots/inch. The bit I don't understand is as follows:- "I have choosen , that the scan shall have 360dpi (that in turn results in 2400ppi for the scanner)"

?

Keith
 

Stuart Richardson

Active member
I think I understand. My scanner also does this -- instead of deciding what ppi to scan at, you can set the "dpi" directly in the scan software, and it will scan at whatever ppi is required to achieve that dpi! It sounds a lot more confusing than it is. So instead of converting to that dpi later in photoshop, you are actually making the scan based on the dpi you want for the output, rather than making as big a scan as possible and then downsizing or upsizing to the require dpi in photoshop.
 

jotloob

Subscriber Member
Jürgen

Sorry, but I'm still confused (this is no critisism of you).
I understand that you are scanning your negative at 2400 pixels/inch and that you are printing your image at 1440 or 2880 dots/inch. The bit I don't understand is as follows:- "I have choosen , that the scan shall have 360dpi (that in turn results in 2400ppi for the scanner)"
?
Keith
Keith
Now you got me . NO ! ! !
You made me get out the SILVER FAST Manual . Unfortunately , it is the german manual . I will try to get a download of an english version .

But one thing is for shure , and it is explicitly written in the manual , that different scanner software and also PSCS as well as printer manufacturer use a different terminology for one and the same thing .
The expressions : ppi , lpi , dpi , spi and quality factor are the ones . And that makes the understanding confusing and difficult .
BTW SilverFast people claim to be one of these confusors , because they look at scanning from the industrial printing buisness side .
That of course is not a great help here .

So I do not see much sense , to explain that mysterious figure 360dpi now , but according to the Silverfast terminology it is the result of a quality factor of 1,5 and a raster of 240lpi . 1,5x240=360 . 360 now called dpi .They call it output resolution .
All very confusing .

I will do some further study , but can only talk from the SF Ai s point of view .

Jürgen
 

KeithL

Well-known member
I think I understand.
Jürgen, I think Stuart has solved the mystery!

Stuart/Jürgen, I prefer to make a full size 'master preprint file' and then base all of the subsequent files - whether they are for print or press - on this master file. Whatever the use it's then a simple matter of resizing before printing or sending to clients for press.

Keith
 

ptomsu

Workshop Member
Jürgen, I think Stuart has solved the mystery!

Stuart/Jürgen, I prefer to make a full size 'master preprint file' and then base all of the subsequent files - whether they are for print or press - on this master file. Whatever the use it's then a simple matter of resizing before printing or sending to clients for press.

Keith
Actually what I do!

1) Scanning with maximum resolution without any care for the print.

2) Retouching the file and do all corrections and have it saved.

3) Convert to actual image size and preferred DPI just before printing - just on the demand of the printer.

Seems to be the most straight forward and clear procedd :thumbup:
 

harmsr

Workshop Member
Actually what I do!

1) Scanning with maximum resolution without any care for the print.

2) Retouching the file and do all corrections and have it saved.

3) Convert to actual image size and preferred DPI just before printing - just on the demand of the printer.

Seems to be the most straight forward and clear procedd :thumbup:
Ditto!
 

jotloob

Subscriber Member
Peter

That is almost exactly my workflow .
Except that I do not scan with the maximum resolution , but with the resolution calculated by SILVER FAST for my maximum print size , my printers can do .

I name the first scan the alpha scan (@scan) , from there I produce an alpha work file
(@work) and after that a final version , which then can be used for the different print sizes . As disk storage is currently quit cheap , the file sizes dont bother me at all .

Jürgen
 

LJL

New member
I concur that is the way to go. By scanning at max resolution, you get a file that will let you do whatever your want now and later, like maybe if your printers change ;-) Rather than scan, and rescan later if needed, you get one good master file that will provide you with whatever you may need later. As you say, since storage is pretty cheap, this is not as big an issue.

LJ
 

JanRSmit

New member
Ah, harmony :angel:
Is'nt it Great.

I do a lot of scanning, simply on maximum resolution and colordepth. One never knows what future use the file can bring. Finalise the resulting image in color-correct, contrast, etc. When done save as master, and from master do any derivation: print, web etc.
Works fine, no issues yet when sending a file to the printer regardless of the resulting DPI. Works ok with PWP, looks ok with LightRoom(just in the process of testing out LightRoom), also on a professional imaging show using Epson it worked fine.

IQ is Technology, PQ is YOU

Jan R.
 
R

Rafa

Guest
That's also my workflow.
I have also found that, for my eyes at least, there is no appreciable difference by doing the upsampling in Photoshop or letting the printer driver do it. As far as I understand, the driver also uses a Bicubic interpolation algorithm. So in most cases I don't do the last step of adjusting the dpi to 360.
I was wondering if somebody has done exhaustive tests and have found situations where it is best to do the resizing in PS vs. letting the printer driver do it.
 
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