File size for printing?

[Kragmeister]

Greetings,

I've been scanning MF B&W negs with an Epson 3170 and Vuescan. I've been scanning at 1600 dpi and having the files scaled to make 10 x 10" prints. In the days when I had a darkroom I used to print 6x6 negs at 10" square on 11 x 14" paper, some habits are hard to break. 🙂

Now the issue. I had a CDR with two files, a 500 mb TIFF and a 60 mb JPEG of the same image. I took it to the local corporate camera shop to try to make a print in the "Digi Print Cafe'" and the workstation wouldn't load the files. A tech told me that they were too big for the workstations but that he could load 'em into the server from another computer. Sure enough, he could read the files on another machine.

He then tells me that having such large files is not necessary to preserve detail, even from 6x6 negs. His contention is that a 3mb JPG is sufficient for prints up to 20x30". I'm not sure about this. Any thoughts?

FWIW, the prints won't be inkjet, instead they are printing on RC photo paper.

Later,
Greg

 

[Ash]

JPEG's are by definition a compressed file.

There's a point where a jpeg tries to be 'uncompressed' and the filesize gets ridiculous. It's all down to the dpi you want to print at. You may as well save as uncompressed, that way ALL the detail from the scan will remain, but the filesize is huge (ie tiff)

 

[kaiyen]

Well, ideal method is to not only resize but to do so at the ppi according to the output device. For instance, if it's a Nortisu, you want 400 ppi. So you'd want to resize to 4000ppi in either direction at 10" square. Once you get that, you save out to TIFF or very slightly compressed jpg and the file size should be manageable.

I use Qimage for this. I set up a "printer" that prints to file of 400ppi. I then print the files and end up with properly sized files that I just send along to coscto online. Files are much smaller than the original scans, certainly.

allan

 

[ffttklackdedeng]

Greg,

If you don't need to process the picture any further (as in your case when the picture is ready for printing), saving as jpg is perfectly fine. You also don't need to save in the 'max quality' setting of your jpg save dialog, 85 to 90 'percent' will be as good as 'maximum'. Thus you really can print from a file which is just a few mb large. How big it will get depends on the picture content, afaik especially on the amount of fine texture details (vs. smooth textures).

To estimate how much is enough for your eyes, you could take a small crop from the file and save it with 85%, 90%, 100% jpg and also as tiff and make 6x4 inch prints from those - I guess you won't see any differences.

Just don't reduce the resolution of the picture - you will see this if you e.g. go below 1000dpi in the scan! 1600dpi for 10x10 inch from MF neg seems fine (although I doubt that the 3170 delivers 1600 - I have one, too and 've been through this).

Have fun, Robert

 

[ffttklackdedeng]

Well, ideal method is to not only resize but to do so at the ppi according to the output device. For instance, if it's a Nortisu, you want 400 ppi. So you'd want to resize to 4000ppi in either direction at 10" square.

Sorry: I think you mean the picture should be 4000x4000 pixel large? From 6x6 MF negative this would mean 1600dpi

 

[ampguy]

See if your printing lab is in this database:

http://drycreekphoto.com/icc/

they may have tools and info. you can use.

 

[kaiyen]

oops - you're right. didn't do the math with the actual size of the negative. My point was that the file you send to the printer should be 4000x4000, but that is just about 1600, yes.

and the 3170 should be able to do just about 1600 true. at least the 3200 seems to, and it's basically the same scan engine.

allan

 

[Kragmeister]

Hey Ampguy!

Dan's Camera City was in the database and I downloaded the ICC profile. When I stop in there Monday I'll ask about their equipment to see if it is the same.

Kaiyen!

I get the idea, and that is pretty much what I did with the large JPEG file that I let them have for printing. I still saved as large file when saving in Photoshop 6.

Guess my plan now is to use the ginormous TIFF files for processing the image then save to JPEG for archiving and printing. This ought to save some drive space too after finalizing the images and dumping the TIFFs into the bit bucket.

Later,
Greg

 

[kaiyen]

My only comment is that you should keep the TIFF as the archive. Or PSD. But JPG for archive....eh...not a great idea.

allan

 

[ampguy]

cool

cool

Good idea to check with them that they didn't upgrade recently or change settings.

Also, if the printer is a 12x18, here's a creative way to do a couple of 8x10's with business cards in the trim:

http://bermangraphics.com/coolpix/noritsu_tips.htm

Hey Ampguy!

Dan's Camera City was in the database and I downloaded the ICC profile. When I stop in there Monday I'll ask about their equipment to see if it is the same.

Kaiyen!

I get the idea, and that is pretty much what I did with the large JPEG file that I let them have for printing. I still saved as large file when saving in Photoshop 6.

Guess my plan now is to use the ginormous TIFF files for processing the image then save to JPEG for archiving and printing. This ought to save some drive space too after finalizing the images and dumping the TIFFs into the bit bucket.

Later,
Greg

 

[Kragmeister]

Hey Kaiyan,

I see the point about saving the TIFF file for archving. Drive space is the issue right now. I need a 2nd larger drive or a DVD burner as I'm maxing out my 40gb drive.

Ampguy!

Thanks for the link to Berman Graphics site, great tips there. The place I usually take my stuff to has a Fuji Frontier, but Dan's Camera is on my commute route.

Later,
Greg

 

[kbg32]

Anything more then 300 dpi in your output file is overkill. Most printers can't handle any more information then that, especially desktop printers. Even though they may print at 2400 dpi, that is usually the output of the ink, not the information from the file.