How to get the most out of your Epson V700, V750, V800 or V850
Have you ever wondered what would be the best settings for your scans with an Epson flatbed scanner? Well, there are two ways of getting those values and one of them is a s simple as reading this blog post. I did some testing with an USAF 1951 resolution target and I will share my findings with you. These settings work great on my scanner, with my mounting solution and chances are that they work for your flatbed scanner as well. Of course the optimal way of doing it, is investing some time and money and do your own tests. In this blog post I will explain what is required to do the tests and provide you with the link to some more detailed explanations. So it is totally up to you if you want to do your own tests or play around with my settings and see if they work for you.
In the past few years I simply used 2400spi (samples per inch) as a standard resolution setting for all my scans, as well as some sharpening presets that seem to work most of the time. After my tests it turned out that these values are close to the optimum settings but with some adjustments I was able to reveal even more and cleaner detail from my scans.
How the Epson Flatbed scanners work
Epson uses CCD sensors (Charge-Coupled Devices) for their scanners and these CCD elements are moved by an stepper motor underneath the glass surface of the flatbed scanner. These two elements determine the theoretical optical resolution in both directions vertically and horizontally. Epson states a theoretical optical resolution of 4800spi for all of their V-series scanners. The optical group that includes the CCD sensor is quite complex and small variations and inaccuracies reduce the optical quality slightly. That means the real optical resolution is smaller than the one stated by Epson.
Other factors on resolution and sharpness
We need to be aware that the optical performance of the scanners may vary from system to system. Additionally the real optical resolution can vary along the scanner surface due to the complexity of the system. Mostly the center is the sharpest and sharpness drops towards the outer areas. Unfortunately there is no focusing option built into the scanner and that means we have to live with the fixed focus that lies somewhere above the flatbed surface. The Epson film holders are optimized for this point, but due to building variations many scanner units are the sharpest at a different height. The film holders can be adjusted slightly, but in order to get the highest possible quality, I suggest doing some tests to find the sweet spot of your personal system. This might be the most important test you really need to do on your own. Feel free to use my values for the optimum sharpness settings but without placing the film correctly on your scanner, these settings are less valuable.
Just a word of warning. For marketing reasons scanner manufacturers often add an additional value to their specifications in order to let their product appear even more powerful. This interpolated resolution does nothing else than up-scaling the digital file. While this is not really bad, it just does not add any additional information or detail to the scan. It increases file size significantly and you can always do the same thing with Photoshop or Lightroom. It makes no sense to clutter your hard-drive with unnecessarily big files.
USAF 1951 - Resolution Test Target
The US Air Force set the standard for testing the performance of optical systems and their test target is still widely used to measure the performance of scanners. The target is printed on positive film and consists of groups of bars with dimensions from big to small. The idea is to find the biggest bar which the scanner is still able to discern. It will determine the maximum optical resolution of the system.
Optimum Film Holder Height
In order to use it properly it is required to mount it carefully and to make sure you scan it at the focus point of your flatbed scanner. A quick way of finding the optimum height of your film holder is, by doing some sample scans at 2400spi resolution and varying the height for each scan. I used several layers of thin cardboard to heighten my mounting solution until I got the best and sharpest scans. The Epson film holders use variable pins to change the height. Sometimes it might be even necessary to increase the maximum height of the original holders even further. If you are like me and use a different holder, you just need to start with the lowest possible height and increase it step by step until you found the best position.
Optimum Optical Resolution Test
Doing all these tests is tedious but simple. You can find a detailed explanation with additional information on the LaserSoft homepage. This document has been designed to be used with SilverFast 6 but should give you a very good explanation of the required steps for SilverFast 8 as well.
We need to make several scans to determine the optimum resolution. Here is a brief overview of the required steps to find the optimum resolution:
- Make a 48bit color HDR raw scan in SilverFast or a 48bit TIFF scan without any adjustments in any other scanner software for the following resolution settings 6400spi, 4800spi, 3200spi, 2400spi and 1800spi. Name the scans accordingly.
- Open the file in Photoshop and zoom to 100%
- Determine the optical resolution of each scan with the use of the table provided on the SilverFast website or the table that comes with the target.
- Make notes and decide which setting works best for you.
Here are my personal results:
scan resolution Vertical Horizontal
1800spi 1825 2048
2400spi 2299 2580
3200spi 2580 2896
4800spi 2299 2896
6400spi 2299 2896
So, we can learn two things from this result. First, the horizontal resolution is a bit better than the vertical and second, the best scan resolution setting would be 3200spi for the maximum amount of detail. If you don´t want big files and look for a good relationship between file size and amount of detail the common setting of 2400spi will still work and give you brilliant results. The smaller resolution might also reduce artifacts and even reduce some grain and scanner noise. So in the end you will have tow options: 3200spi for the absolute maximum amount of detail and 2400spi for a cleaner final image. You can read more about how the chosen resolution might affect your grain rendering this article: Grain Resolution and Perception
Now it is time to find the best sharpening settings for the two scan resolutions we are using with the Epson V-Series. Use the two Tiff files you have created with 3200spi and 2400spi resolution and use the sharpening settings in your desired image editing software.
Her are my settings for Photoshop, SilverFast and Adobe Lightroom:
Lightroom: Amount 65 Radius 0,7 Detail 85 Mask 0
Photoshop USM: Amount 160% Radius 1,0 Threshold 0
SilverFast: Power 240 Radius 1,9 Threshold 0
Lightroom: Amount 70 Radius 0,7 Detail 90 Mask 0
Photoshop USM: Amount 190% radius 1,3 Threshold 0
SilverFast: Power 260 Radius 2,2 Threshold 0
The auto sharpen setting in SilverFast works very well, even though I found that with the resolution target a lower setting will give you cleaner details.
In order to get the best amount of detail we should find sharpening settings that increase the perceived amount of detail and do correct for scanner inaccuracy. In a later step we will be able to include creative sharpening or local adjustments. I kept the radius slide relatively low in order to maintain the separation of the bars in the test target. For certain images it might be useful to change that. This largely depends of content as well as the used film type. Especially film with a larger grain structure would probably require a different amount of sharpening. Experiment with these settings and use them as a starting point.
After some more testing with these settings I found that what works well for a resolution target might introduce artifacts like halos at high contrast edges in some images. I established a fallback sharpening setting to avoid these halos. They read as follows:
Lightroom: Amount 40 Radius 0,8 Detail 20 Mask 0
i did some More testing and found tagt my go to combination fort Most scans is a scan resolution of 2400spi while sharpening the files in Lightroom later on with the above mentioned settings. This will give me less artifacts as well as the most pleasing grain structure.
Removing other Artifacts
Now that we know about the optimum resolution, we need to look at other inaccuracies created by the scanner. I encountered quite significant chromatic aberration when scanning the test files. With the help of Lightroom these artifacts can be largely removed. I recommend using the CA removal setting in Lightroom or Adobe Camera Raw for your scans. I have mentioned in previous posts that I am using a two step workflow. I first scan the file in SilverFast and than optimize the files in Lightroom. Presets are your best friend here. You can easily make two presets for each mentioned resolution and include the sharpening settings, chromatic aberration removal and some noise reduction. Noise reduction would require some more tests. I found it very helpful to include some basic noise reduction to all my scans as this will eliminate scanner noise to a high amount.
In the end I was quite surprised how much detail can be extracted with a flatbed scanner. The film height plays an enormous role. This test should have the highest priority. At a input resolution of 3200spi you are able to achieve a perceived optical resolution of approximately 2800spi. This value is more than what I have expected. I call it perceived resolution as without sharpening the test target suggest a lower optical resolution, around the common suggestion of 2400spi. Let me end this post with a short disclaimer. Even though I mentioned it already, I would like to stress that these are just my findings, my settings that work for me. Feel free to use them, but keep in mind that your system might be slightly different or you sharpening aesthetics are different compared to mine. All my tests have been run on an Epson V700, but I expect similar results from the V750, V800 and V850. If you are using a V550 or V600, you should run your own tests to find the optimum resolution settings for these scanners.
I would be very interested in hearing your thoughts or personal experiences with your scanner. Good luck with your tests!