Image Sharpening

[Jim Ford]

Originally Posted by pressld2

If you need to edit in Photoshop after raw conversion then you should convert to a 16 bit tiff file for this. Then do whatever you need to do, sharpen last - still in 16 bit tiff - and then save as an 8 bit jpeg.

I aggree with this, but I don't always save to 16 bit TIFF for Photoshop. I really ought to, but my PC is a bit slow!

Jim

[mickmassie]

You guys have lost me here. So take it slow please.

I use the Photoshop RAW dialogue, set my crop, exposure and curve adjustments, then I say 'Open Image' to go the the regular Photoshop dialogue. I have not converted to TIFF or JPEG or anything else. At the end of whatever processing I do (in my case mainly Lab Color sharpening and final exposure tweaking) I then save the file as a JPEG or TIFF or whatever. Before that, is the file I am working on an 8bit or 16bit ? It isn't a JPEG until I save it as such.

I don't save the image as JPEG and then keep working on it, I always start with a RAW image, and don't convert to JPEG until the end.

Am I still losing quality by Lab Color sharpening after the RAW dialogue has finished ?

Mick.

[col188]

I always use RAW, process to TIFF using Capture one, convert to sRGB/Jpeg and resize for upload.
Don't use sharpening in camera or RAW conversion, but do, smart sharpen after conversion, and then again before final upload to web.
Works fine for me, and I'm often surprised at the improvements.
Col

[pressld2]

Originally Posted by mickmassie

You guys have lost me here. So take it slow please.

If it's any consolation, I lose meself half the time too!

Just to make it even more complicated most raw files are 12 bit but a few cameras (my Nikon D300 included) can save 14 bit raw. I don't think there are any that capture 16 bit images to start with but someone may correct me on that.

As far as I'm concerned, if I just want to tweak the exposure, saturation and white balance a bit, or play around with curves then I'll do it in Lightroom on the raw file. I use the 14 bit option, by the way, just because it's there, but I can't honestly say that I can see any difference from the 12 bit files from my old D70.

Only if I want to do anything more extensive, particularly anything involving layers or selective adjustments to part of an image then I will first save it as a 16 bit tiff and then make all the adjustments to that file. 16 bit because that's the highest quality available and tiff because it's a "lossless" format which means that the quality doesn't degrade each time you save it - unlike a jpeg. I only save it as an 8 bit jpeg once all editing is finished and it's ready for upload.

Dave P.

[mickmassie]

So back to the point where I started to get worried.

"Some Photoshop gurus recommend converting images to Lab mode, sharpening the lightness channel, then converting back to RGB. However, unless the image actually requires some other operation that demands Lab mode, roundtripping from RGB to Lab to RGB is somewhat destructive on 8-bit/channel images (you lose anywhere from 30 to 35 of the 256 levels available due to quantization error) that can lead to hue shift and possible posterization." He then goes on to say that on "16-bit/channel images the quantization error is a non-issue."

I shoot 14 bit RAW, with the 'lossless compressed' option. I don't convert to JPG or TIFF or whatever until after I have done all of my photoshop processing. I don't think I am in any '8-bit' danger as described by Jim (quoting Bruce) above and I think I am safe to keep pressing my 'Lab Sharpen' button. If I was staring with a JPG as my source file it would be different, of course. Can anyone reassure me on that ?

Mick.

It's good here innit ?

[col188]

As long as you have the original file archived, you can always go back to it. TIFF is lossless and is best processed in 16bit (8bit ok though), finally converting to Jpeg for upload or printing........and of course can be compared to, a jpeg converted and processed file.
Really depends on what quality the end product needs to be.
Col

Originally Posted by mickmassie

So back to the point where I started to get worried.

"Some Photoshop gurus recommend converting images to Lab mode, sharpening the lightness channel, then converting back to RGB. However, unless the image actually requires some other operation that demands Lab mode, roundtripping from RGB to Lab to RGB is somewhat destructive on 8-bit/channel images (you lose anywhere from 30 to 35 of the 256 levels available due to quantization error) that can lead to hue shift and possible posterization." He then goes on to say that on "16-bit/channel images the quantization error is a non-issue."

I shoot 14 bit RAW, with the 'lossless compressed' option. I don't convert to JPG or TIFF or whatever until after I have done all of my photoshop processing. I don't think I am in any '8-bit' danger as described by Jim (quoting Bruce) above and I think I am safe to keep pressing my 'Lab Sharpen' button. If I was staring with a JPG as my source file it would be different, of course. Can anyone reassure me on that ?

Mick.

It's good here innit ?

[Lee70]

Hi all

I've tried most of the suggestions that have been put forward and in the end i didn't find much difference between any of the final outputs i did.

I did however come across Nik Sharpener Pro 3.0 which is a plugin for Photoshop.It allows you to pre-sharpen your RAW file and then once you have done all your other things to your image and saved it.You can then sharpen the image again for final output.

It's like a 2 stage sharpen and the results for me swayed me to keep it on my system.

You can download a trial from here : https://www.niksoftware.com/site/

Just click on the downloads section.

Thanks to everyone for their input

Lee

[PMG]

Thanks Lee for bringing the question up - its given me a chance to rethink what I do and why - glad you've settled on something - will take a look later

Pauline

[Lee70]

Originally Posted by PMG

Thanks Lee for bringing the question up - its given me a chance to rethink what I do and why - glad you've settled on something - will take a look later

Pauline

Hi Pauline

Your welcome.

I didn't realise just how many techniques there are to sharpening an image.

If it wasn't for the members on this site i probably would have been stuck with photos that i were never quite happy with.I've even ran some of last years family holiday snaps through it and they look so much nicer.
So once again a big thank you to everyone for their help.Without it i would have been throwing away far more photos than i needed to.

[acherontia]

Originally Posted by Lee70

Hi Pauline


I didn't realise just how many techniques there are to sharpening an image.

Many, many ways Lee! If you want to sharpen in jpg then the best way is using layers - it's far subtler and avoids it looking obvious.

Personally I only ever ever sharpen in RAW. If the image doesn't hold up at 100% -200% it generally goes in the bin. I'm so used to doing it this way for stock sites who will not accept over sharpened images. Also - I'd much rather be out and about taking the images than spending hours trying to recover an image that really shouldn't have the effort spent on it - I used to but have learnt better! Some I do save for ID purposes though.

To the trained eye it is very obvious when an image has been over post processed and those editors at Alamy etc. are real swines about image quality!!

But for personal use I'd recommend using layers when sharpening - but there are a few ways of doing that too!The one Dorseteye described is a typical one and more effective than using the 'sharpen' 'sharpen more' or 'unsharp mask' commands.

Also - you mentioned hand shake. Have you thought about using a tripod or a bean bag? Anti shake does help (especially if it has different settings) but it's not always foolproof. I don't know what kind of camera you have but you could think about speeding things up with different apertures, shutter speeds and ISO settings.

OH's hands aren't has steady as mine so for hand held macro work he tends to use on board lighting (twin flashes) to speed things up.

A very vast subject, isn't it ???

Acher