MobileRead Forums - View Single Post - Optimum scanning resolutions for images in Sigil?

Jim the Obscure · 11-03-2012, 08:17 PM

I'm in the process of assembling my first ePub book (Gertrude Jekyll, Wall & Water Gardens @ 454 KB / 91 pp of text in MS Word Doc) and will be using Sigil to do so once I've scanned the 150 odd b&w photographs (+/- 3 1/2" x5 1/2") in it. I did a test scan on my HP flatbed @ 300 ppi / 256 grayscale and got a 1.42 MB file (which is going to add up) so I tried the same grayscale at 150 ppi and got a 260 KB, which is better, but would still add up to about 40 MB in images alone - couldn't see much difference in quality between them. I will be importing them into Word 2003 and saving as HTML, Filtered, then opening in Sigil (which I’m still learning).

My question is (& I've searched a lot) what is the optimum PPI resolution for scans of b&w photographs to be imported into Sigil for display on both e-readers and in something like Calibre on a computer? What is the trade-off point between file size and quality in terms of resolution? Most of the ePubs that I've downloaded from places like archive.org are crawling with OCR errors from the Google scans and I've edited this text carefully for spelling (horror show of old & Latin plant names and tons of italics) and would like it to look nice but not be too huge. Also wondering about resolutions for colour scans too for future projects. (Best saved as JPEG's?)

I post a lot of cleaned-up text of (mostly) old gardening book excerpts on my blog (jimtheobscure.com) if anyone's interested – ps - wordpress.com doesn't support the upload of ePubs but I contacted Scribd support (looking for a place to park some) to inquire and they replied that they hope to be supporting them within the next quarter - now to work on Wordpress.

Thanks!

11-03-2012, 08:17 PM	#1
Jim the Obscure Jim the Obscure Posts: 5 Karma: 180 Join Date: Nov 2012 Location: Vancouver, British Columbia, Canada Device: none (Calibre)	Optimum scanning resolutions for images in Sigil? I'm in the process of assembling my first ePub book (Gertrude Jekyll, Wall & Water Gardens @ 454 KB / 91 pp of text in MS Word Doc) and will be using Sigil to do so once I've scanned the 150 odd b&w photographs (+/- 3 1/2" x5 1/2") in it. I did a test scan on my HP flatbed @ 300 ppi / 256 grayscale and got a 1.42 MB file (which is going to add up) so I tried the same grayscale at 150 ppi and got a 260 KB, which is better, but would still add up to about 40 MB in images alone - couldn't see much difference in quality between them. I will be importing them into Word 2003 and saving as HTML, Filtered, then opening in Sigil (which I’m still learning). My question is (& I've searched a lot) what is the optimum PPI resolution for scans of b&w photographs to be imported into Sigil for display on both e-readers and in something like Calibre on a computer? What is the trade-off point between file size and quality in terms of resolution? Most of the ePubs that I've downloaded from places like archive.org are crawling with OCR errors from the Google scans and I've edited this text carefully for spelling (horror show of old & Latin plant names and tons of italics) and would like it to look nice but not be too huge. Also wondering about resolutions for colour scans too for future projects. (Best saved as JPEG's?) I post a lot of cleaned-up text of (mostly) old gardening book excerpts on my blog (jimtheobscure.com) if anyone's interested – ps - wordpress.com doesn't support the upload of ePubs but I contacted Scribd support (looking for a place to park some) to inquire and they replied that they hope to be supporting them within the next quarter - now to work on Wordpress. Thanks!