Converting 14-bit scans to 8-bit from Nikon Coolscan V-ED

[chris_schofield]

<p>I scanned the first 100 of about 2,000 slides with my Nikon Coolscan V-ED at 14-bit depth, then later decided to scan the remainder at 8-bit. Each 14-bit scan is over 100 Megabytes.<br>

<br />Is there any way I can convert the 14-bit scans to 8-bit? I can open the file in Nikon Scan 4.0, and use 'Image->Color Space->24-bit RGB', and save, but the file doesn't get any smaller. Nowhere can I find a way to change the bit depth directly. I can open the file in Photoshop, and use 'Image->Mode->8-bits/Channel', and then the file gets much smaller, but I'd like to make the change before I get into Photoshop. Thanks!</p>

[digitaldog]

<p>Big files but you might just want those high bit scans:</p>

<p>http://www.digitalphotopro.com/gear/imaging-tech/the-bit-depth-decision.html</p>

<p>But you can also just build a Photoshop droplet after making an action to sample to 24 bit color. I have no idea how else you could do this outside of Photoshop and in the Nikon software. </p>

[bgelfand]

<p>Since you have Photoshop, I recommend you create a Photoshop action to convert from 16-bit to 8-bit color. Then use the Photoshop batch processing function (FILE > AUTOMATE >BATCH) to convert your files all at once.</p>

[randy_myers3]

<p>Storage is dirt cheap these days. Keep the bits.</p>

[victor_ho2]

<p>http://www.hamrick.com/<br>

Vuescan software. I believe that this will allow you to resize your images. You can check with the support site. They are pretty good at answering. And the best news is that you can batch convert your files. So assign a source folder with 14 bit files and designate a destination folder for the smaller files. Then you have to decide if you discard the larger files. I bet you keep them because it's painful to think about rescanning again. If you're not using this software to scan, it's worth looking into. The files are very good and the scan software is supported and updated by Hamrick. It's also faster than the Nikon software. Vuescan works with multiple scanners and with all the latest system software. I switched because the current Mac OS does not work with Nikon software. Nikon does not support software upgrades any longer. The Vuescan software does the 'ICE' thing as well as Nikon. I really did no special cleaning for multiple slides (thousands - tens of). </p>

[robert lee]

<blockquote>

<p>I scanned the first 100 of about 2,000 slides with my Nikon Coolscan V-ED at 14-bit depth, then later decided to scan the remainder at 8-bit. </p>

</blockquote>

<p>Look harder, there is a pixel data size selection in the Nikonscan GUI. </p>

<p>More importantly: <strong>don't do this, you'll regret it</strong>. I'm sure you've come to find out by now that scanning is super labor intensive. The Nikon is decently fast, but 2000 frames will still cost you 3 to 6 months of time; I've done it. It isn't something you want to do more than once. </p>

<p>The difference between 8 and 14/16 bits pixel depth is significant the moment you need to do any post. Once you've thrown the bits away, they're gone forever.</p>

[david_henderson]

<p>Wouldn't you be better off making the scans in 14 bit, doing any editimg you might need ( and nearly all scans need a bit of editing in my experience) and then converting to 8 bit as a last act (mode/8bit) when your satisfied with your pictures. So the 14 bit space thing becomes temporary and doesn't get out of hand if you edit soon after you've scanned rather than leaving all the editing till after you've done all the scanning. Doesn't help the scan time of course, but you need to believe that you need to set this off against better quality files.</p>

[chris_schofield]

<p>Regarding "Look harder, there is a pixel data size selection in the Nikonscan GUI." - I see an entry under 'scanner'/'bit depth', but that is only valid when the scanner is plugged in and sets the bit depth for future scans, not existing scans. I can't find any other place where bit depth can be modified (other than 'image'/'color space', but that has no effect on size).<br>

I will not actually 'throw away' the scans that I've already done at 14-bit - I always save originals, but will create an 8-bit working copy that is then consistent with 80% of other scans I made.<br>

I understand the argument for 14-bits vs 8-bits - somewhat like the argument for shooting 'raw'. The reason I don't generally shoot raw is the same reason I don't want to work with the 14 bit scans ... it's not just a storage issue (more bytes), but also, an issue of time (time to scan, time to later load, time to step through and 'review', etc).</p>