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Capture Sharpening for the E-1

in Olympus E-System , Thursday, October 06, 2005

After nearly two years with the E-1, I think I have finally made some progress on how to extract maximum sharpness from RAW files. It is often said that E-1 RAW images can take a lot of sharpening. Exactly why this is the case I guess depends on several factors, but my own experience tends to back this up. Until now, my workflow has been to process images from RAW to TIFF using CaptureOne, but disabling all sharpening. I then sharpen in Photoshop, using a capture sharpern / output sharpen method supported by Pixelgenius Photokit Sharpener. Over time I have tried various tricks, such as increasing the opacity of the sharpening layers, or duplicating the capture sharpen step (a suggestion from one of the Pixelgenius team). Recently though, I read a commentary on RAW sharpening by Alain Briot at Digital Outback, which got me thinking. Alain's method was to capture sharpen in the RAW converter, using Photokit for output sharpening. Since here he was using CaptureOne (before he sold out to RawShooter :-) ), I decided to try it myself. I have been reluctant to use RAW converter sharpening in the past, due to several factors. First, it isn't so clear how well the algorithms compare with Photoshop, and the level of control, and especially of documentation is poor or non-existent. Second, it is equally unclear if sharpening is done as part of the RAW conversion process, so somehow able to work with a level of information detail not available in an output TIFF, or if it is applied post-processing, and finally because various "gurus" say not to. However, if it is good enough for Alain Briot, it is certainly good enough for me. The next question is "how much sharpening do I need". What I want is to apply enough to bring out detail and minimise the softness introduced in the RAW conversion, but I don't want to overdo it, I want to see detail, but I don't want to see the kid of obvious sharpening I would see in a file prepared for printing. The only way to find out is to try it. So I did. I am a bit dubious about the value of the image below. It is difficult to appreciate much from a small uploaded JPEG. However, the fragment on the left was sharpened in CaptureOne, with sharpening settings Amount:0 Threshold:2 (yes, there is a big difference between 0 and "disable"). The one on the right is with CaptureOne sharpening disabled, and PhotoKit Sharpener's Digital MedRes, Medium Edge Sharpen capture sharpener. sharpen.jpg The sharpening is actually almost identical, although I'd give a slight edge to CaptureOne. But what is far more noticeable, at least when I look closely in Photoshop, is that Photokit is introducing a slight "smearing" effect, as well as some edge effects. I can boost the sharpening level in CaptureOne without introducing any such artifacts, but more to the point, their presence will have an effect on further output sharpening. I should make it clear that I consider Photokit to be excellent, and I will certainly use it for capture sharpening of scans, and output sharpening of everything. And it could be that this result could be changed with fine tuning, and also that it is very specific to the E-1 (although Alain Briot doesn't use an E-1). I'm also not going to reprocess every E-1 image I have on file. But in future, I will capture sharpen in CaptureOne, and if I'm making large prints of existing images, I may well go back to the RAW and reprocess.