Mark Good questions. I'm using the Epson software. Some of the things I would like to know more about are:
1. How do you limit the blocked up shadows areas? When I use backlight selection, I just get a lot of red dots in the scanned photo especially in the shadow areas.
2. Which are better to scan and post process if you bracketed an exposure? The under, over or calculated exposure shot?
3. Which pre-scan selections do you use and why? How do you set them up? (I don't use any except ICE and make all changes PP to speed up the scan process and reduce the overall amount of processing time I have to spend).
4. Do you handle these selections differently between 35mm and MF?
5. Which films do you find scan best with the flat bed?
6. How do you straighten the curled negatives?
7. What non-Epson scan software do you use and where does it work best for you?
I was hoping to get a discusion started that we all could trade on our experience so we all can scan better.
Epson Scan is a fairly limited application which nonetheless has the key tools needed to at least get a decent scan into Photoshop or Photoshop Elements where you can continue working on the image. You may wish to download demo versions of VueScan and SilverFast Ai6 to see whether those programs would better address your objectives.
The first thing about opening shadows is to check whether the film itself is exposed in a manner that the shadows can be opened. If you think they can be, and you are working in Epson Scan, it would be best to try doing this with the histogram and tone curve adjustments. The best exposure for scanning will be the one which doesn't clip highlights or shadows. Check the histogram in Epson Scan to determine which exposure has the most well-behaved histogram. If you must compromise, avoid exposures which clip all three channels in the highlights, because that is unrecoverable, whereas shadows which look plugged can often be opened somewhat in the software.
I scan in 48 bit colour (this is 3 channels by 16 bit each) because this maximizes the amount of data which can be used for post-scan adjustments, and minimizes risks of banding and posterization. If Photoshop Elements cannot handle 16-bit data, that's OK, scan in 16-bit anyhow because one day you may wish to reprocess these scans with an application that is 16-bit capable. You can convert a duplicate of these scans to 8 bit for Elements, but keep the original as a 16-bit file.
In the Configuration options you should go to the Color section, select Color Sync and within that menu select the ARGB color space and the correct profile for your scanner from the drop-down list in "Scanner Source". I would recommend ProPhoto colour space, except that Epson Scan doesn't provide it.
There is no need to scan everything at 2400 PPI. It depends on the output dimensions and output PPI you will need. For example, if you scan a 35mm frame at 2400 PPI, you will have 3600 pixels on the long dimensions. If you print that at 360 PPI, you can make a print with a 10 inch long dimension. With this kind of calculation, think of the largest output size you are ever likely to make and the output resolution you will require, then scan-in at the corresponding input resolution. It may be more or less than 2400 PPI.
As for how to set-up your scans in Epson Scan, click the Help button at the lower left of the Epson Scan interface.
You raise a question about which things to do as part of the scan and afterward. The configuration options, and exposure correction are the most important to do at the scan stage, because mishaps here could be difficult to recover with decent quality afterward.
Anything suggested here is valid regardless of whether the input media is 35mm or MF.
I don't find any film scans best with a flat bed. Epson is is as good as it gets for flat-bed scanning, but a good, dedicated film scanner will deliver more detailed scans. Unfortunately the best of these scanners are either costly or hard to find or both. If you can find a decent buy of a Minolta Scan Elite 5400 original or model 2, or with more difficulty, one of the later Nikon Coolscan models, they will out-perform the flatbeds. As well, you may wish to check-out my article on the Plustek 7600iAi on this website.
Dealing with curled negatives is difficult. Ideally, if the scanner allows you to scan them on glass, you can get them held down temporarily by wetting the underside with film cleaner. If this approach can't be done with that scanner, you need a frame-holder which flattens the film. The frame holder I have for the Epson V750 isn't too bad for that, but not stellar. You may try flattening the negatives under a few heavy books for a week or so and see whether that helps, being careful that nothing transfers from the book to the negatives.
I use SilverFast Ai6 Studio for all my scanning - it is all 'round the most complete scanning solution on the market for all the scanners discussed here.