# Twain scanning: gigantic file size?
**URL:** https://boards.straightdope.com/t/twain-scanning-gigantic-file-size/71891
**Category:** Factual Questions
**Created:** [July 10, 2001, 12:00am UTC](https://boards.straightdope.com/t/twain-scanning-gigantic-file-size/71891 "2001-07-10T00:00:15Z")
**Posts on this page:** 11
**Page:** 1
### Author:  [@Johanna](https://boards.straightdope.com/u/Johanna)
#### Post date: [July 10, 2001, 12:00am UTC](https://boards.straightdope.com/t/twain-scanning-gigantic-file-size/71891/1 "2001-07-10T00:00:15Z")
I would like to know why every time when I scan a picture with Twain, the result is such a huge image file. It gets blown up to be over 10 times the actual dimension of the picture.
I just scanned a color picture whose dimensions were about 4x6 inches. The resulting .jpg turned out so blown up, the person was bigger than life size. The .jpg was 26 MB!!! It was enough to choke the memory of Photoshop when I tried to shrink it down. My issue is not only with the amount of bytes, but the dimensions in inches too.
The scanning software I have been using is ScanSoft PaperPort 6.5 on a Brother MFC 9200C. The Twain has only three settings: resolution DPI, color type, and scanning area size (the last of these does not affect the blow-up phenomenon).
How do I simply scan a picture at **actual size?**
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### Author:  [@Gaspode](https://boards.straightdope.com/u/Gaspode)
#### Post date: [July 10, 2001, 12:49am UTC](https://boards.straightdope.com/t/twain-scanning-gigantic-file-size/71891/2 "2001-07-10T00:49:46Z")
All the scanning software I’ve used scans the image at ‘actual size’, it’s only the resolution that varies.
If the image size is too large the problem is with your resolution. If you only want to use the image on screen set the resolution at 75-100 DPI. If you want to print it, scan the image at slightly over your printer’s maximum resolution.
When printing set the software to print at the size of the original image if their isn’t a "print actual size’ option.
You can easily re-size to whatever actual dimensions you want in pretty much all editing software provided the resolution isn’t so high it causes the system to crash/hang.
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### Author:  [@bordelond](https://boards.straightdope.com/u/bordelond)
#### Post date: [July 10, 2001, 12:50am UTC](https://boards.straightdope.com/t/twain-scanning-gigantic-file-size/71891/3 "2001-07-10T00:50:02Z")
You’ll have to play with the resolution, though it is unclear from this end whether you’ll have to increase it or decrease it.
Just as an experiment, scan something at the scanner’s max DPI, then at 300 dpi, then at 72 dpi. Compare the final file sizes. If your scanner is marketed to home users simply wanting to put pictures online, then 72 dpi is probably the ticket.
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### Author:  [@London\_Calling](https://boards.straightdope.com/u/London_Calling)
#### Post date: [July 10, 2001, 1:02am UTC](https://boards.straightdope.com/t/twain-scanning-gigantic-file-size/71891/4 "2001-07-10T01:02:29Z")
Whoa – hope you got a lot of RAM 😉
Yep, as above. What I’d add is that sometimes the little box (often a scroll down) for determining the dpi is pretty small so it’s possible to not realise there can be more than the default resolution setting.
My next stage (I guess there are other ways, some probably better) would be to open the image in Photoshop and go: Image (from the menu bar thingy) \> Image Size. That gets the image to the dimensions you want, however, its probably still a very large file.
Then you need to optimise the image if you plan to use it on the web so go: File \> Save For the Web (in Photoshop 5.5 and above).
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### Author:  [@Mac\_Guffin](https://boards.straightdope.com/u/Mac_Guffin)
#### Post date: [July 10, 2001, 1:18am UTC](https://boards.straightdope.com/t/twain-scanning-gigantic-file-size/71891/5 "2001-07-10T01:18:14Z")
All scanning software I ever used has a resolution setting. The higher the resolution, the larger the pic. I would have to know what scanner you own to say for sure, but you should check out the website for the manufacturer of your scanner. You should find a list of FAQ’s there that should help.
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### Author:  [@AHunter3](https://boards.straightdope.com/u/AHunter3)
#### Post date: [July 10, 2001, 1:48am UTC](https://boards.straightdope.com/t/twain-scanning-gigantic-file-size/71891/6 "2001-07-10T01:48:06Z")
To your computer, an image file 4" x 6" at 360 dpi is the same as an image file 20" x 30" at 72 dpi, except for the instructions it sends to the printer about how densely to array the pixels.
So the image size that matters (to you and the computer) when you are setting up your scan is the pixels horizontal by pixels vertical. You can optimize the image to fit the printed page afterwards.
If your scanning s/w doesn’t have size in pixels as an option, try scanning a 1" x 1" square at different available settings and check the image size in pixels in Photoshop to see what those settings equate to per original inch of scanned material.
A 26 MB JPEG sounds like a fairly large image scanned at 400 dpi or an 8.5 x 11 image scanned at 600. Of course JPEGs vary considerably in size depending on quality and various other factors such as colors and color distribution in the image, but that’s my guesstimate.
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### Author:  [@Skywatcher](https://boards.straightdope.com/u/Skywatcher)
#### Post date: [July 10, 2001, 7:44pm UTC](https://boards.straightdope.com/t/twain-scanning-gigantic-file-size/71891/7 "2001-07-10T19:44:28Z")
**Jomo Mojo** , did you know you can tell twain to reduce the scan size? I normally scan a 4x6 at 300dpi and 75%. The resulting image is more manageable.
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### Author:  [@astro](https://boards.straightdope.com/u/astro)
#### Post date: [July 10, 2001, 9:39pm UTC](https://boards.straightdope.com/t/twain-scanning-gigantic-file-size/71891/8 "2001-07-10T21:39:00Z")
Also remember in many cases you need to set an image window size just prior to scanning for the item to be scanned. This is usually a floating dashed line you can move and resize to encompass the item to be scanned. If you do not do this the scanner will typically try to scan the entire scanning bed area of 8x11 or 11x14 and your file size will be huge even with a medium small photo.
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### Author:  [@TheNerd](https://boards.straightdope.com/u/TheNerd)
#### Post date: [July 10, 2001, 10:10pm UTC](https://boards.straightdope.com/t/twain-scanning-gigantic-file-size/71891/9 "2001-07-10T22:10:57Z")
As an aside, did you know that twain merely stands for “technology without an interesting name”?
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### Author:  [@Kamandi](https://boards.straightdope.com/u/Kamandi)
#### Post date: [July 10, 2001, 10:36pm UTC](https://boards.straightdope.com/t/twain-scanning-gigantic-file-size/71891/10 "2001-07-10T22:36:16Z")
> [@](#):
>
> \*Originally posted by TheNerd \*
> \*\*As an aside, did you know that twain merely stands for “technology without an interesting name”? \*\*
Cite?
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### Author:  [@sailor](https://boards.straightdope.com/u/sailor)
#### Post date: [July 10, 2001, 11:33pm UTC](https://boards.straightdope.com/t/twain-scanning-gigantic-file-size/71891/11 "2001-07-10T23:33:43Z")
> [@](#):
>
> [Si non e vero, e ben trovato](http://whatis.techtarget.com/definition/0,,sid9_gci213232,00.html)
> In several accounts, TWAIN was an acronym developed playfully from “technology without an important name.” However, the the TWAIN Working Group says that, after the name chosen originally turned out to be already trademarked, an 11th hour meeting of the group came up with TWAIN, deriving it from the saying “Ne’er the twain shall meet,” because the program sits between the driver and the application. The name is not intended to be an acronym.
Other sources about TWAIN: [HP](http://www.hp.com/cposupport/scanners/support_doc/bps01512.html) and [http://www.twain.org/about.htm](http://www.twain.org/about.htm)