Sme scanner/printing questions

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atlcruiser

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Hi,
I am now scanning 35 and 120 on my canon flatbed. Cant remember what model 🙂
Maybe I am just confused here...
I am using photshop elements to crop and fiddle with negs as required. I want to be able to send to the web as well as get large size commercial prints made in both color and B+W.

How big do I need to scan to get a large size print made? If i run the 120 at 800 dpi it is 4+ mg. If i go much larger Elements will not be able to handle the file size. I keep thinking bigger is better but if i cant get it into elements I end up with a big raw neg to print. At times that is OK but I really need occassional cropping.

I am lucky in that i have a good commercial printer locally. Talked to tham a bit but I think they are a bit over my head. Main thing I got from them was acess to the FTP site, file type, and to make sure the files are in RGB colorspace. Very little info on what size files give me what quality/size print.

My workflow is weak right now as I am learning; at least i hope i am!

Currently shooting 5+ rolls of 35 and 4+ of 120 per week. All B+W get developed at home and the C41/E6 is done with the local camera shop (We really have one of those). I am scannign everything I get at low DPI to see it and use for the web. Negs that i think are really worth a good look are rescanned at a higher DPI which gets back to the question above.
Any suggesstions on workflow would be great. My GF is really tired of me stayign up till 2am every night with the scanner going.

thanks
 
Without more details (scanner model and your definition of "large size commercial prints") no one can give you hard specifics.

In general, to get close to the full detail in most films, you need to be scanning at around 2400 to 4800 ppi. It depends largely on the film's grain size and resolution and the resolution of the lens used when taking the picture. This scanning resolution does not change with film format except that larger format lenses generally have somewhat lower resolving power, in absolute terms (they do often have more relative to image size).

Personally, I generally scan 6x6 and 6x7 format 120 films at 2400ppi and 35mm films at 3200ppi, though there are frequent exceptions. I scan my 4x5 and 3-1/4x4-1/4 Polaroid T665 P/N negs at 2400ppi with few exceptions. For me, the largest prints I typically make are 12x18 images on 13x17 paper.
 
To calculate scanning pixel density, take the length of your desired print, multiply by 300, and that is (actually more than) the number of pixels you will need on that side to get a decent print. So, 10" will need 3000 pixels.

Divide that number by the corresponding length on your negative-a 2" negative measurement would indicate a 1500 ppi scan.

To keep the file size down, don't do TIFF. Waste of time. If you don't believe me, try a TIFF and a JPEG of the same file, see if you can tell the difference. The printer will almost certainly convert to JPEG anyway.
 
Thanks!

On workflow:
Do folks scan mutiple times depending on the use of the particular scan; print size. Or scan once and just mess with as needed.
 
atlcruiser said:
Thanks!

On workflow:
Do folks scan mutiple times depending on the use of the particular scan; print size. Or scan once and just mess with as needed.
Click to expand...

For 35mm film (Leica M4-2) I scan at 3600PPI with Plustek 7500
For 120-6x6 BronicaSQ I scan at 2400 with Epson 4180+Betterholder
For 120 6x9 Bessa-I I scan at 1200 with Epson 4180+Betterholder
I then use LR to crop and size images for the desired size(s)
 
aad said:
...To keep the file size down, don't do TIFF. Waste of time. ...
Click to expand...

TIFF is far from a waste of time!

Scanning to JPEG has a number of serious disadvantages. JPEG involves lossy compression, though when the compression is modest the damage in minor. The big limitation is that JPEG is an 8bit per pixel (24 bit RGB) format. TIFF, on the other hand, supports 16pit per pixel (48 bit RGB). Using this latter format allows the scan to retain more of the subtle highlight and shadow detail and tonality.

The third way is to scan from a good image editing program (e.g. Photoshop) avoiding the disk file save between scanning and editing. This way you can scan at 48bit and have that 48bit image passed to the image editor for final adjustment. You can then, if you wish, reduce it to 24bit and save as a minimally compressed (PS "quality" of 10-12) JPEG. This workflow allows you to do all of your adjustments and editing on the 48bit scan data.
 
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