Eight vs. sixteen, how many bits do you need?

[bakuretsu]

After writing my fairly well-received histograms article, a few people took me to task on a statement I made about the difference between making tonal changes in 8-bit versus 16-bit. I've lurked in several threads on the topic and it seems to divide many photographers; unnecessarily, I think.

So I opened Photoshop and I started playing around. I have my way of doing things and I wanted to see if it made any sense at all. Turns out, it does. I think this exploration will be helpful for everyone who is looking for their own optimal workflow, so I wrote another article about it.

How Many Bits? Is Eight Enough?

I'll ask everyone here the same question I asked at the end of the article: what are your workflow preferences when it comes to 8-bit vs. 16-bit? If your camera supports RAW and you shoot JPEG, why? (Another debate in and of itself.)

 

[fmw]

I think the major reason people shoot JPEG is that the camera does some of the post process so it saves time in Photoshop. Personally, it wouldn't save me enough time to worry about it so I shoot everything in RAW.

Well, almost everything. I shoot web product photos in JPEG. I have no post processing at all to do except resize. I can knock them out in less than 30 seconds each in photoshop.

An advantage of RAW shooting, at least for me, is that I can ignore all of those stupid menus and settings in the camera. I'm proud to say I use well less than 10% of the cameras "features."

 

[EOS_JD]

Mostly 8 bit..... Can't be bothered with the additional stage to convert most of the time.

However if it's an important image that looks to be losing detail in PP then I'd try 16bit. But that's rare indeed.

 

[PNA]

Read your first article.....learned something.

On the second one.

 

[DigitalDiva]

When I took a digital printing course, we almost always converted from 16 to 8 bit once editing was completed. It greatly reduced the file size once it was flatted and converted. We were making 8x10 300dpi images that were scanned or RAW images. I'll read your article next. Read your article. Very useful!

 

[PNA]

Second one read.....

So your suggested work flow would be: RAW>TIFF>JPG....?

 

[skieur]

I shoot in both jpeg and RAW. 16 bit gives you more colours to work with in editing and better gradations between colours, which is absolutely necessary in some shots. A lot of shots need colour correction in postprocessing and most beginners do not have the eye to notice the problems.

The best approach for top quality is to shoot and do editing in RAW, save to TIF to do the finishing touches and perhaps use software filters and then print. Certainly for some work that is somewhat time consuming and not necessary and in those cases I would shoot in jpeg.

skieur

 

[DigitalDiva]

I go from RAW to TIFF for printing but always print from an 8-bit TIFF and I have technically clean prints.

 

[ksmattfish]

So I opened Photoshop and I started playing around.

Can you give more details as to how you performed your test? When I used levels in PS to expand 60 to 190 gradients in 8 bit and 16 bit I couldn't see any differences between the two.

I shoot raw, and edit in both 8 bit and 16 bit. I like post processing, and the raw workflow, but I can see how jpeg would be more advantageous for a different photog. Many, many, many successful pros shoot jpeg and edit in 8 bit.

For me bit depth is usually a decision based on available time. My computer takes a little longer in 16 bit, and if I've got hundreds of photos to get through that can really add up. In general I guess I'll blindly fall in with the "bigger must be better, right?" crowd, but more and more I'm coming around to the idea that as long as the exposure is good, and I'm not doing any radical editing, 8 bits is more than enough. I can't seem to spot the difference in large prints, and that's usually good enough for me.

 

[Garbz]

16 makes sense for editing, nothing beyond that. Why people would shoot in JPEG instead of RAW is beyond me. The only thing that could possibly be useful is having extra space for a further 400 photos on their memory card. It's not saving or wasting time. Eventually the photographer will be previewing the photos on the computer, and the good packages that allow them to do that will automatically convert to an 8bit JPEG in a batch if they are pleased with how everything came out.

That's my workflow. RAW from the camera. I look at all the photos in Lightroom. Delete the crap ones. Adjust the good but slightly stuffed up ones usually only a white balance correction since I always shoot in daylight. The ones that need further editing go into Photoshop. When I am finished I select the entire album click export to JPEG, and then delete the DNGs to save space.

I believe in basic economics of cost vs performance. Shooting RAWs makes sense to me. Keeping them if I will never actually edit them again doesn't.

 

[Big Mike]

There was a good article in 'Digital Photo Pro' a few months ago, that gave a good explanation of why 16bit is better than 8bit.

 

[RVsForFun]

...but I'm told you can't even see 16 bits worth of color on your monitor. Your RGB color monitor can't show the full 8-bit RGB (16.7 million colors) spectrum anyway, so editing in 16-bit can only show a portion of that colorspace at one time.

Until a 16-bit JPEG standard is adopted, used on the web, used to print with and completely replaces all electronic projection devices, you're dealing in an 8-bit JPEG world.

 

[Mike_E]

Under 20" 8 bit, over 20"s 16 bit. 20"s ~ eh, depends on what it is.

mike

 

[D-50]

Unless file size is a major concern why not edit and store files in the best formats. I shoot in RAW and convert to uncomressed Tiffs for editing then I save in Tiff. Yeah my files range from 30 to 100mb depending on the size but you can always buy more space to put your files in.

 

[Garbz]

Because the sheer logistics of moving AND backing up literally thousands of raw files scares me. Then there's the problem of everytime I send one I need to convert it, put it up on the net, convert it.

I think of RAW as I think of 8bit vs 16bit. It makes a lot of sense when editing files to keep information way beyond what the monitor or printer is capable of, but when you're done with editing they just use up useless space. I personally don't see the point since I don't go back and edit images after I am finished with them, and I can't see a difference between a Q11 JPEG and a RAW. Heck even a difference map in photoshop shows now difference.