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I have read that fluid mounting effects the process of drum scanning more than say, DSLR scanning. Something about the way the light interacts with the sensor. I do not own a drum scanner, but I can say that in my tests the improvements that come from fluid mounting for camera scanning are marginal at best. I really saw very little improvement. However on an older dedicated CCD line scanning medium format rig, the fluid mounting made a big difference.
So it really is a YMMV thing I have to say.
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I use Vuescan. It basically will give you wysiwyg. What you see is what you get. I prefer Vuescan ro anything epso has. If you want to try it out download a trial copy. Or if you want t use Epson software got to Colorperfect for how to do it uou have several steps to and need Colorperfect to do so.
Another thing is your scan will appear dark as no gamma encoding applied. If converting manually you first need to apply a gamma of 2.2. I use Colorperfect and it does a much better job at conversion than manual or otherwise although I can get pretty close manually.
The superiority of a linear scan for standard photo work is debatable. It certainly wasn't standard practice for high-end scanning during the heyday of film scanning. Steven can correct me, but I believe it's use comes from astro photography. With regular photo scanning, it seems most useful for scanning color negatives. I don't use it for BW scanning or slide scanning.
“You often feel tired, not because you've done too much, but because you've done too little of what sparks a light in you.”
― Alexander Den Heijer, Nothing You Don't Already Know
It does have its biggest uses in science, but it also has a good use for anything digital including film scanning. I have not really played with it for positive film scans, but for negatives, color and bw I use it.
Whether scanning film or using a digital camera the data is a collection of electrons representing photons that fill up pixel wells. Once a well fills up it spills into the surrounding wells. When that happens, data is lost. If no gain is applied, sometimes called an offset, then applying one which we do when a plying a gamm a curve blindly will cause a loss of data. Some cameras apply an inherent offset to avoid having values equal zero, such as Nikon. This leads to no actual black values.
The gamma curve of 2.2 applies an expansion and compression of values to enhance contrast,but in doing so, data can be lost, ie blown out or shoved to zero. Neither is good. On top of this the conversion process then applies a series of adjustments proprietary to a camera maker. For a scanner, the conversion routines attempt to mimic different films. Additionally, we also make adjustments to the scan data to refine it to get what we are after.
When you save this "final" image you have baked in the formula, ie,you can't undo it,and lose your ability to get back to the raw data without rescanning.
By scanning the image with nothing "cooked" in,you are free to convert and adjust as many times as you like having made only one scan. It also allows better control over pulling in highlights and darkness. If they are blown out nothing will help though. Same with black, if all zeros, there is no data and cannot be recovered.
I like to have absolute control over the data so I prefer linear raw scans.
If someone prefers to do it all at scan time that is perfectly acceptable.
For astronomy, astrophotography, the same applies for scanning film, but has a unique application for digital capture. The reasons are the same as above,but the explanation and reasons why are much more complex that involves noise reduction and pulling out hidden data gems and maximizing the sensor data capture. All this can also be applied to scans.
In digital capture of any scene you have three things you are dealing with, sensor read noise ( where captured sensor data is read by the analog to digital converter AD. This is similar to film grain which is random), dark current noise and sensor bias (pattern noise). We also take flat frames to counter sensor dust, vignetting and lense dust. You also have the same things in scans however, while you can take dark frames and possibly bias frames (I need to see if that can be done since bias frames are typically taken at .001sec or faster and I don't know if that can be done on the scanner)
Typically at least 50 dark frames are taken at the same exposure time as the image, in this case the length of time of scan at chosen dpi. Next a series of 200 or more bias are taken, may or may not be possible on a scanner, easily done on digital camera. Then 200 or more flats.
All this is done to remove noise and increase the signal to noise ratio by averaging and subtracting these calibration images from a series of actual images that have been averaged together before any debarying is done (this is done whether the sensor is color or monochrome) and any gamma applied, called stretching in the astro world.
Could this be applied to film scans? Most easily if using a dslr or mirrorless camera, possibly with flatbed scanners not sure for drum,and of course it would be all about your end goal. For film astrophotography it would the way to go. Basically what all those calibration frames do is allow one to characterize the sensor and remove its influence on the final product.
That was a cliffs note version.
"can be lost" doesn't entail that important data is lost. Your statement seems to say that the big danger in applying a gamma to the scan data is that the endpoints shouldn't be clipped. I agree that endpoints shouldn't be clipped, and one can do that without using a linear gamma. Many of us have decades of practice doing so. What I don't want is people new to scanning thinking that they need to jump into having a linear gamma, or getting Vuescan, or.... I've use a lot of scanning applications, and Vuescan is my least favorite, btw. My advice is to get the basics of scanning down. Don't jump in and do a whole bunch of scans. Rather, do a scan and take it to it's completed end use, whether onscreen or a print. Evaluate and try to do better. Once the basics are nailed down, then by all means investigate other options. What I'm saying is do the work, and be careful about magic bullet chasing.
“You often feel tired, not because you've done too much, but because you've done too little of what sparks a light in you.”
― Alexander Den Heijer, Nothing You Don't Already Know
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