editing tiff file?

[bimmer88]

hi , im a new user of D1 and i 've got a problem, after i convert image to tif 16bit ,i realise that i cannot editing the images in photoshop? can anyone tell me wat to do if i wanna do some editing? Thanks

[henkbos]

You're probably eager to start so a quick respons. I think you have to convert to 8bit TIFF before you can use some PS functions. Give it a go.

[Don Ellis]

Patient: "Doctor, Doctor, it hurts when I do this."
Doctor: "Then don't do that." :p

Which means in simplest terms that you convert to 8-bit and forget about it.

But if you'd like to convert to 16-bit, you can do Contrast, Levels, Curves, Hue, and Saturation in 16-bit mode. Then convert to Mode, 8-bit, and do everything else.

Cheers,

Don

[bimmer88]

Hi thanks for the reply, but after i drop it to 8bit...the image drop from 23mb to 11.6mb? so does that mean my image will not be as sharp if i wanna blow it up to 20inches?Thanks again!

[Don Ellis]

[Please note -- most of this particular message is ompletely wrong, as Roger Cavanaugh thankfully pointed out. Sharpening is certainly possible on 16-bit images in Photoshop and I apologize for misleading anyone. I'm leaving this message in place simply for continuity. Please ignore it for content...]
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Well, let me put it this way -- you're not going to be able to sharpen a 16-bit image in Photoshop, so you'll end up with a sharper image by reducing it to 8-bit and sharpening, rather than staying with an unsharpened 16-bit image.

I haven't done a lot of printing but it's been my experience that 8-bit is adequate for properly exposed photos. The 16-bit allows you a little more latitude, of course, with curves and contrast.

Having said all this, there might be a program that allows you to work with 16-bit images throughout the enhancement process, including sharpening.

Good luck,

Don

[Roger_Cavanagh]

You can do a substantial amount of 16-bit editing in Photoshop 6 or 7 (those are the versions I've used) including sharpening using the Unsharp Mask filter.

As Don has already mentioned most of the critical adjustments like curves and levels can be done in 16-bit. The most obvious function that is not available in 16-bit is layers.

Personally, I prefer to stay in 16-bit as long as possible. 8-bit conversion throws away an awful lot of data. I find that I can postprocess the vast majority of my images completely in 16-bit and only convert to 8-bit JPG for web galleries.

Here are some useful articles on 16-bit including more explanation on why high bit editing is a good thing:

http://www.creativepro.com/story/feature/7627.html
http://www.creativepro.com/story/feature/16097.html
http://www.computer-darkroom.com/16bit/16bit_1.htm

Regards,

[Don Ellis]

Roger_Cavanagh wrote: You can do a substantial amount of 16-bit editing in Photoshop 6 or 7 (those are the versions I've used) including sharpening using the Unsharp Mask filter.
Hi Roger,

You are one kind man not to use the large club on me for my sharpening comment. These days I often use a combination of Ultrasharpen Pro and then Unsharp Mask to sharpen my photos and Ultrasharpen won't work on 16-bit files -- so, my comment.

Thank you for correcting that. One of the benefits of Pekka's forum is that we can correct our misstatements so I'm going to add an "Ignorant Fool Disclaimer" right now.

Cheers,

Don