chris_strom

You are welcome, Vincent.

I am using Vuescan, too. It has its pitfalls, but once you know them it is pretty reliable.

I had a similar issue with Silverfast when I tried to evaluate whether to use Silverfast or Vuescan to obtain RAW scans. I wrote to technical support and got a good explanation how Silverfast works. But I have to admit, the answer is stored at home in my private mailbox.

As far as I remember, when using the HDR 48bit output, the gamma setting is of no importance. It will change the appearance of the preview window, but not the actual file output. It would alter the output if you choose an 48bit output WITHOUT the HDR mode. I may mix up thing now with Vuescan, but I think it has something to do with whether you want to have all the image manipulation functions of Silverfasts scanning software included (you would use normal 48bit mode, only usable in the professional version, not SE version) or if you want to have just the pure sensor signal (48-bit HDR mode). ColorNeg, in this case, relies on the HDR 48bit file which is by nature of the sensor data, in linear gamma. You have to assign the working color space of your image editor while opening just because ColorNeg has to make sure that there are no color space conversions in the background by the image editor to shift between working color space and image color space. The plugin is very sensitive to color space mistakes.

Christian

Vincent, I can answer this question, if Mark doesn't mind.

Scanning raw does not take IT8 calibration into account. In terms of slides, this is not a problem. You can use a commercial or free ICC creation tool (e.g. LPROF ICC profiler) to create an ICC file based on a scan of the IT8 target and the IT8 information file. To use it afterwards, copy the created ICC profile to your system directory and use an ICC profile capable image editor like Photoshop. While opening the RAW file, there should be no color space ASSIGNED to it and ideally, you are asked to do so. In the drop down list of color spaces available, further down below you should find the one you created (listed with the name you gave it during the creation process). After applying the profile, the colors of the image are corrected. Afterwards, CONVERT the image to your working space color space, e.g., AdobeRGB.

In terms of negatives, this is not possbile. You can only rely on ColorPerfect to identify unusual color drifts and to care for them. The two most important things to watch out for when using the ColorNeg part of ColorPerfect for negative conversion is (from my personal experiences)

a) make sure that the RAW scans you obtain are in linear gamma

b) whatever colorspace you assign to the RAW file while opening in photoshop, make sure it is also the working color space set within photoshop preferences and to not convert it afterwards until you have finished the work within the ColorNeg plugin.

Best wishes,

Christian

PS: for some reason, the editor does not recognize my carrier returns...

Indeed Mark, Rishi's explanation is correct. In fact, by personal experiences, I can confirm that using an inappropriate IT8 target leeds to false color casts. When I am back home, I can post an example of what happens in this case and what the differences look like. Its not that in every case it looks wrong, but different. Often, the color cast is visible in the shadows.

Christian

<p>Mark, what you describe is indeed the usage of the IT8 calibration target. It offers the possibility to adjust the scanner output to standardized and calibrated readings of a laboratory, therefore allows for the truthfull reproduction of colors, at least as far as the scanner hardware allows for.<br /><br />But the target has to be made specifically for the film you are going to scan. In terms of Kodak slide film, this is simple as Kodak states that the target can be used for the complete range of Kodak Ektachrome Slide film, probably because the film base and materials are similar.<br /><br />But in terms of Fuji slide films, different targets are necessary. This is because the various films use different kind and numbers of layers and substances which can lead to different color appearance for the scanner's sensor. Often, one target can be used for different Fuji films (e.g. one target is for Provia 400X and Astia 100F), but e.g. Velvia RVP50 needs a special one. The physical nature of this effect is called metamerism, which leads to different color responses depending on which film is used in combination with which (scanner) light source.<br /><br />A good source for Fuji slide film IT8 targets is Wolf Faust at <a href="http://www.targets.coloraid.de"><cite>www.targets.coloraid.de</cite></a><br>

Christian</p>

<p>There are so many variables in testing a scanner, the difference in results hardly surprises. I'll give you an example.<br /> <br />I personally own a Silverfast resolution target. That is the one used in the resolution tests of filmscanner.info. If I insert this resolution target into my Plustek 7600i with the frontside upwards and scan it with 3600 dpi, I get this:<br /> <img src="http://img707.imageshack.us/img707/6279/scan12122100013600front.jpg" alt="" width="600" height="576" /><br /> I think, it is fair to say that symbol 5.6 is resolved into seperated lines, which would translate to 2896 dpi. Not bad! 3200/2896, thats 90% efficiency.<br /> If I raise the scanning resolution to 7200 dpi, I get this:<br /> <img src="http://img547.imageshack.us/img547/3702/scan12122100027200front.jpg" alt="" /><br /> I think it is valid to say, that 6.3 (thats the 2nd symbol in the 6 column because the 6 comumn starts with symbol 6.2) is besing resolved, albeit very low contrast. This is equivalent to 4096 dpi scanning resolution. Impressive for a consumer scanner at this price point.<br /> <br />If I now flip the resolution slide and insert it with the backside upwards, I get vastly inferior scans:<br /> <br />3600 dpi scan:<br /> <img src="http://imageshack.us/scaled/landing/600/scan12122100013600backu.jpg" alt="" /><br /> 7200 dpi scan:<br /> <img src="http://img585.imageshack.us/img585/7889/scan12122100027200backu.jpg" alt="" /><br /> <br />This would lead to much lower measured resolution figures. But why should anybody do this, you might ask. Well, maybe because he used the scanner for scanning slides before conducting this test. Let me explain:<br /> <img src="http://img821.imageshack.us/img821/3959/scan1212210003syltoverv.jpg" alt="" width="1024" height="686" /></p>

<p>This is a shot of a ferry boat that shuttles between the german isle of Sylt and the danish isle of Rømø. I took it on Fuji Velvia RVP50 using an AF-S 50mm f/1.4 at what I remember to be f/5.6 and about 1/160-1/250s as it was bright sunlight. This roll of film was developed at a well known professional studio in germany, farbglanz.de. But the following experiences are valid for cheap mass laboratories as well, as my experience has shown.<br /> If I insert this slide into the Plustek 7600 with the frontside upwards, just like the resolution slide for optimal performance, and scan the small part in the near center of the frame, I get this:<br /> <img src="http://img526.imageshack.us/img526/9968/scan1212210003syltback.jpg" alt="" width="1416" height="720" /><br />Not bad, and while I was running my first scans with the Plustek, I thought this would be it.<br /> But then I tried flipping the slides, and in this case, the corresponding scan looks like this:<br /> <img src="http://img833.imageshack.us/img833/5696/scan1212210003syltfront.jpg" alt="" width="1320" height="720" /><br /> Now thats an improvement!<br /> <br />I suspect that depending on the construction of the slide frame, the actual film within the frame is position in different heights. The depth of field of the scanner cannot compensate due to the lack of an AF and in case of the Plustek 7600i, the native depth of field is not cast enough to allow greater variances in film height. For the slide frames I buy and use, it is better to flip the slide for scanning. In case of the resolution target and the slide frame it is using, it is better to scan the other way around. Other users might have experienced the same without knowing, which would explain the differences in apparent resolution of the same scanner. Also, it might not always be possbile to perfectly adjust to the actual plane of focus just by flipping the slide.<br>

Christian<br>

PS: larger images are displayed in reduzed size. judgement of shaprness and resolution should be performed with the images maximized. otherwise, false conclusions could be drawn.</p>

<p>I think we can be glad to have Mark from Plustek to give us updates from time to time. Usually, you do not get anything from the manufacturer before release. When Nikon delayed the release of the D800 due to the disasters, nobody was curious as Nikon did not release any info about an upcoming product before. It was just the rumor mill suggesting that delay, which was later confirmed by persons working together with Nikon.</p>

<p>Also, Mark communicates on additional platforms like Flickr where e.g. he stated that official information from Plustek USA will be released 30 days prior to sale. There are other platforms as well, just google a bit, e.g. rangefinder forum.</p>

<p>There was been a lot of information released so far, much more than usual for a manufacturer which is very kind of Plustek. It was said that the original delay was caused by the "one of the big" sensor manufacturer whose sensor devision was sold, which makes it likely that the original sensor should have been a Kodak. If you have a look at Kodaks linear CCD sensor portfolio, you'll see that they do not offer a sensor which resolution is as high as the one the new OpticFilm 120 is going to have. If there aren't sensors in Kodaks product range that are not listed in their catalog, it is likely that by switching to the new sensor, the OpticFilm 120 also gained a plus in resolution, which makes the delay really less of a worry. BTW, if I am not mistaken, the stated resolution suggests a Toshiba linear CCD sensor (TCD2957BFG) which would do the job, coupled with a respective lens. If one is interested in further technical details beyond the ones given so far, looking deeper into the sensor specs should give some info about what capabilities to expect.</p>

<p>Chris</p>

<p>I own the Plustek OpticFilm 7600 and if the new OpticFilm 120 can transfer the quality of the 7600 over to MF, it will already be worth buying. Nevertheless, there is still room for improvement :-) Looking forward to its release!<br>

- Chris</p>