Traction engine
Discussion
dcw@pr said:
That is simply not true,
"Oh yes it is" [Pantomimemodeoff]
Perhaps I'm not making sense (wouldn't be the first time), I'll try to give a more detailed answer.
At no point in my above post did I say that editing in 16 bit wasn't an advantage over 8 bit. Yes, I agree, it does give give smoother adjustments and less posterisation, but it cannot, somehow, magically, restore missing information.
You mentioned 12 bit which is was what most DSLRs capture the image at. 12 bit captures 4096 shades of gray. If your camera is set up to produce JPEG, the camera initially captures the image as, 12 bit RAW data, then it uses its pea sized brain to apply white balance, sharpness settings etc, depending on your preferences, and then produces an 8 bit image with a mere 256 shades of gray. Then, to add insult to injury, it compresses your file. The initial RAW data is gone, lost forever. Shooting JPEG is limiting your cameras ability. It's like having a V8 engine and switching off two cylinders. (just to keep it car related
) My point was that if the file was in RAW format to start with, much, much more information can be retrieved from it than trying to do it in post production. If you can manipulate the first image in this thread using 16 bit editing, to show the missing detail in the polished brass I would love to see it.
Just had a look back through the archives at this thread with has a picture which, I think, illustrates my point. Fortunately Steve has both the JPG and RAW files still on his site.
Trying to retrieve the detail in the sky from the JPG, even in 16bit mode is hopeless. Just quickly, using tricks like duping the layers and setting blending mode to multiply and applying curves just produces this:
A better result could, possibly?, be achieved with a bit more time. If you can achieve it, or have any tricks please share, It's always nice to learn something new.
Now, using Adobe RAW converter to process the RAW file, I think you will agree that somewhat more detail is available.
And if you use a better RAW converter like Capture One DSLR you can make larger adjustments for something like this:
And, again, if you process into 16 bit colour you will have more chance of hanging on to that detail with any further adjustments in PS.
Nine times out of ten, shooting in JPEG will give you perfectly satisfactory results for most snaps. But, if you really care about ultimate quality, shoot RAW. I only shoot RAW although, in 12 bit, only about 10% of the time. Much prefer 16 bit with 65, 536 shades of gray to play with.
Hope that makes a 'bit' (pardon the pun
) more sense now. Cheers
Paul
(P.S. Hope the pics show up OK. Sometimes when I preview I'm getting red Xs although I've double checked my formatting. If they don't show I'll host them on a site.)
I see what you are saying - but it appears you misunderstood the point I made originally. I didn't say that converting to 16bit will mean you can recover more detail, I said that it will help in the transition phase between the blown out areas and the correctly exposed ones. If you look at the original picture, you will see there are some funny artefacts in this area, which may possibly be avoided (or lessened) by editing in 16 bit.
Something I've never understood is why can the camera not save the JPEGs at 12bit? Is this an inbuilt limitation of the format?
Something I've never understood is why can the camera not save the JPEGs at 12bit? Is this an inbuilt limitation of the format?
dcw@pr said:
I see what you are saying - but it appears you misunderstood the point I made originally. I didn't say that converting to 16bit will mean you can recover more detail, I said that it will help in the transition phase between the blown out areas and the correctly exposed ones. If you look at the original picture, you will see there are some funny artefacts in this area, which may possibly be avoided (or lessened) by editing in 16 bit.
Perhaps I did misinterpret your original post. If so I apologise. So yes, you are correct. If you want to edit with the best possible results, do it in 16 bit, but, if you want to avoid the problems in the first place, shoot RAW.
dcw@pr said:
ISomething I've never understood is why can the camera not save the JPEGs at 12bit? Is this an inbuilt limitation of the format?
Not sure, possibly. But then again, 12 bit will take up more storage on a card than 8 and still won't give the advantages of RAW so why not just shoot RAW to start with? If you need to access JPEGs quickly shoot RAW + jpg, best of both worlds. After all cards are getting bigger and cheaper all the time.
It seems this thread has been hijacked slightly...but it's a subject I am interested in so here goes.
On my camera there are a few options for storing your photos-
1)JPEG (I will ignore the lower compression settings). Smallest file size (~3mb), therefore more can be fitted on the card, and it also takes less time to write them as they are taken - this is a point which is often overlooked. As a tradeoff you get compression artefacts, although these are very very small with the highest settings. You also only get 8 bit files, and the white balance is fixed. Sharpening is not an issue as this can be turned off if you so wish.
2)TIFF. Huge filesize (~18mb) so very slow write time, and very inefficient for storage space. theoretical quality benefits over JPEG, but in tests that I have done myself I found the difference to be only just detecatable. IMHO TIFF is useless in this application.
3)RAW. Obviously this has all the advantages already mentioned, such as more detail captured, and changeable white balance (again, I don't understand why this can't be done with JPEGs?). However, RAW files take considerably more time to process once they are off the camera, assuming that the equilvalent JPEG image has been taken to a reasonable quality and does not neeed to much fiddling. They are also big files (~14mb) with the problems that brings. I can also save compressed RAW files, which are half the size, but the camera takes significantly longer to process these, which can slow you down out in the field. Shooting JPEG + RAW is a total waste of time, I think. Stop sitting on the fence!
It is undoubtedly true that for maximum quality above everything else, photos should be shot in RAW. But I often have to process hundreds of photos within a few hours, or thousands within a few days. Even with a fast computer, this is not possible - you might as well just take the photo right in JPEG to begin with! If I were a landscape photographer (then I wouldn't be using a dSLR...) and I had enough time on my hands, then it would be RAW all the way.
What do you reckon?
On my camera there are a few options for storing your photos-
1)JPEG (I will ignore the lower compression settings). Smallest file size (~3mb), therefore more can be fitted on the card, and it also takes less time to write them as they are taken - this is a point which is often overlooked. As a tradeoff you get compression artefacts, although these are very very small with the highest settings. You also only get 8 bit files, and the white balance is fixed. Sharpening is not an issue as this can be turned off if you so wish.
2)TIFF. Huge filesize (~18mb) so very slow write time, and very inefficient for storage space. theoretical quality benefits over JPEG, but in tests that I have done myself I found the difference to be only just detecatable. IMHO TIFF is useless in this application.
3)RAW. Obviously this has all the advantages already mentioned, such as more detail captured, and changeable white balance (again, I don't understand why this can't be done with JPEGs?). However, RAW files take considerably more time to process once they are off the camera, assuming that the equilvalent JPEG image has been taken to a reasonable quality and does not neeed to much fiddling. They are also big files (~14mb) with the problems that brings. I can also save compressed RAW files, which are half the size, but the camera takes significantly longer to process these, which can slow you down out in the field. Shooting JPEG + RAW is a total waste of time, I think. Stop sitting on the fence!
It is undoubtedly true that for maximum quality above everything else, photos should be shot in RAW. But I often have to process hundreds of photos within a few hours, or thousands within a few days. Even with a fast computer, this is not possible - you might as well just take the photo right in JPEG to begin with! If I were a landscape photographer (then I wouldn't be using a dSLR...) and I had enough time on my hands, then it would be RAW all the way.
What do you reckon?
dcw@pr said:
3)RAW. Obviously this has all the advantages already mentioned, such as more detail captured, and changeable white balance (again, I don't understand why this can't be done with JPEGs?).
I guess there's just not enough info left in the file. A 14mb file is going to contain more info than a 3mb. It's just the way it is. Until they come up with a new 'RAWJPEG' format (and they most probably will) you will have to live with it.
dcw@pr said:
It is undoubtedly true that for maximum quality above everything else, photos should be shot in RAW. But I often have to process hundreds of photos within a few hours, or thousands within a few days. Even with a fast computer, this is not possible -
Capture One is very slow but, IMHO, produces the best quality. Adobe Raw converter is fast, coverts a 1ds RAW to 32 mb in about 5 sec's (2 1/2 year old Mac dual 1ghz G4). You run batch process with an action so that's 500, give or take, allowing a little for saving to disk time, per hour. Depending on camera/file, your milage may vary. For that extra quality, yes, you will have to do more work and possibly buy some more hard drives. Only you can decide if it's worth it (think I know the answer
). dcw@pr said:
What do you reckon?
As I said, nine times out of ten (most probably 98 out of 100), JPEG will be fine so, if ultimate quality isn't a priority, I reckon you should stick with JPEG unless, of course, it's a traction engine.
Oi Simpo! In future, stick to cats... a lot less troublesome.
Right, in my imaging travels (not all camera shot) but it's all just pixels 'init?
1) TIFF - pointless, outdated format written by people who couldn't program. Laterly (about the same time man started standing mostly upright) it got some compression in it. It is the choice of disk drive salesmen.
2) JPEG - Nice DCT based lossy format with an 8bit per channel standard. Yes you can do DCT's (Discrete Cosine Transforms) with more than 8 bits but I suspect that it's not done as A) most decoders can't handle it and B) all the 8 bit code is public domain and no-one can be ar5ed to do higher bit depths and get it widely accepted.
3) RAW - Compressed loss free camera specific format. It's the best as A) that's all the info there is to be had and B) there's no air in it.
4) Fractal - Really quite amazing compression and fantastic quality. Produces the odd strange effect every so often however. Massive amounts of CPU power to compress so no good for portables. No public source code (that's any good).
So, in short, shoot RAW unless you can't be bothered with the extra workflow....I have a feeling that may have been said before
?
Still, I like the pics. Be nice to try to get some with some movement in them to try to show just how much on traction engines spins and moves. They're a sod to drive BTW...Did it years ago...but that's a different story.
1) TIFF - pointless, outdated format written by people who couldn't program. Laterly (about the same time man started standing mostly upright) it got some compression in it. It is the choice of disk drive salesmen.
2) JPEG - Nice DCT based lossy format with an 8bit per channel standard. Yes you can do DCT's (Discrete Cosine Transforms) with more than 8 bits but I suspect that it's not done as A) most decoders can't handle it and B) all the 8 bit code is public domain and no-one can be ar5ed to do higher bit depths and get it widely accepted.
3) RAW - Compressed loss free camera specific format. It's the best as A) that's all the info there is to be had and B) there's no air in it.
4) Fractal - Really quite amazing compression and fantastic quality. Produces the odd strange effect every so often however. Massive amounts of CPU power to compress so no good for portables. No public source code (that's any good).
So, in short, shoot RAW unless you can't be bothered with the extra workflow....I have a feeling that may have been said before
? Still, I like the pics. Be nice to try to get some with some movement in them to try to show just how much on traction engines spins and moves. They're a sod to drive BTW...Did it years ago...but that's a different story.
thatphilbrettguy said:
Be nice to try to get some with some movement in them to try to show just how much on traction engines spins and moves. They're a sod to drive BTW...Did it years ago...but that's a different story.
Interesting idea - but it was only at 'tickover' so I'd have needed a 1"+ exposure and a tripod. And probably an ND filter as well!
Still, there's always PS
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