Epson 3200 File Size with Vuescan vs Epson

[David R]

I scanned one medium format B/W negative with both the Epson 1.25a and
Vuescan 78 software. Can someone explain why such a file size
difference?

334,584KB - Epson 1.25a (w3.627" x h4.612", resolution 3200)
96,814KB - Vuescan 78 (w3.663" x h4.517", resolution 3200)

I saved them to an uncompressed TIFF file. My scan settings were as
follows

16 Bit Gray for both software
Scan Resolution at 3200 for both software
Filters on Vuescan were set at Restore Color On, Restore Fading On,
Grain Reduction Off, and Sharpen On.
Filters on Epson 1.25a were set at Unsharpen Mask Filter Level High.
Target Size Original for both software.
Crop size was as close to the same for each.

Both scans look excellent. The Epson scan took half the time as the
Vuescan time.

 

[Mac McDougald]

I scanned one medium format B/W negative with both the Epson 1.25a and
Vuescan 78 software. Can someone explain why such a file size
difference?

334,584KB - Epson 1.25a (w3.627" x h4.612", resolution 3200)
96,814KB - Vuescan 78 (w3.663" x h4.517", resolution 3200)

I saved them to an uncompressed TIFF file. My scan settings were as
follows

16 Bit Gray for both software

3.6 x 4.6 inches @ 3200ppi = apprx. 161MB in 8bit grayscale, double that
for 16 bit.

The VueScan one is too low for even 8 bit, so you must have either:
- set output size to something smaller for save
- used LZW even though you didn't mean to.

Check pixel dimensions of both. They should be relatively close, but I
bet they're not.

Mac

 

[Mac McDougald]

Check pixel dimensions of both. They should be relatively close, but I
bet they're not.

Mac

I should have concluded, "OR LZW got applied".

M

 

[David C Miers]

Vuescan outputting tiff files defaults to some compression if it's left on
auto. You'll have to change it to get to the tiff settings.

 

[Leonard Evens]

Vuescan outputting tiff files defaults to some compression if it's left on
auto. You'll have to change it to get to the tiff settings.

Tiff lossless compression should not make such a large difference in
file size unless the image is highly unusual in distribution of tones.

Most likely the Vuescan scan was actually made at some other setting.

 

[David R]

I should have concluded, "OR LZW got applied".

M

The Epson Pixel size looks much larger. Here are the reading as viewed by PS.
Epson Pixel Dimensions: 326.7M (w11606 x h14758)
Vuescan Pixel Dimensions: 161.5M (w11720 x h14453)

 

[Bruceh]

The Epson Pixel size looks much larger. Here are the reading as viewed by PS.
Epson Pixel Dimensions: 326.7M (w11606 x h14758)
Vuescan Pixel Dimensions: 161.5M (w11720 x h14453)

(11,606 * 14,758) * (16bits/8bitsPerPixel) = 342.56 MB
(11,702 * 14,453) * (8 bits/8bitsPerPixel) = 169.13 MB

In Viewscan, is the setting for Output|Tiff file type set to
"16-bit gray" or "8-bit gray"? It should be the former.

 

[Mac McDougald]

The Epson Pixel size looks much larger. Here are the reading as viewed by PS.
Epson Pixel Dimensions: 326.7M (w11606 x h14758)

That's right for 16 bit.

Vuescan Pixel Dimensions: 161.5M (w11720 x h14453)

That's right for 8 bit.

So, you saved the VueScan one at 8 bit, and since you say the saved VS
image is only 96MB on disk, you must have LZW compression on it also.
Simple as that.

Mac

 

[Erik Krause]

Hello, David R
you wrote...

The Epson Pixel size looks much larger. Here are the reading as viewed by PS.
Epson Pixel Dimensions: 326.7M (w11606 x h14758)
Vuescan Pixel Dimensions: 161.5M (w11720 x h14453)

To know exactly what happend you can go to libtiff.org and get the
libtiff software package (for windows follow the windows binaries
link). The tiff tools are part of the package, tiffinfo gives you the
appropriate infos.