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sophiecentaur
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I always wonder why different manufacturers have so many RAW formats /algorithms. Is it Licence issues?
sophiecentaur said:It's amazing that we see the rigging at all at that distance. It can't be bigger than 10mm and could be 6 or 8mm. (less than 10^-5 radians at a km distance). For an aperture of 20mm and a wavelength of 800nm, the Rayleigh criterion gives a resolution of 2X10^-5. No wonder it's all a bit fuzzy - right near the limit for discriminating two adjacent rigging lines so when they cross, that blur is only to be expected.
Whatever our equipment can do for us, we always want better.
Borek said:No, but we shot mostly in RAW, and what we see on our monitors is in RAW as well, we just convert for jpg to show pictures on forum. At this stage - I can speak for myself only, but I doubt And2 do it much differently - I choose compression level so that the effect I am referring too is still visible. As far as I know at zero compression level jpg is a loseless format, be sure I will not hesitate to use it if I will find it necessary.
sophiecentaur said:<snip>
On the subject of Haze; I have looked all over for a filter that would (sharp-) cut out the far end of the visible Blue. This, I am sure, would reduce the worst of the haze - allowing more contrasty pictures - without knocking out all the Blues. Distant mountains can be made to look a lot sharper if you reduce the gain in the blue but this, of course, wrecks the colour balance. I'm convinced that some clever filter could help a lot.
Why isn't there anything about? (or is there?) It could be that filters (other than polarising) are not used much with digital photography because Photoshop can do most of it after the event.
Andy Resnick said:I exclusively shoot JPG. I can see the compression artifacts on occasion, but so infrequently that I can't justify the added time and effort needed to deal with RAW.
sophiecentaur said:RAW files are hardly more trouble, actually. <snip>
Perhaps they are just more trouble in the application you are using. Using Aperture 2, you wouldn't be aware whether you were importing Jpeg or RAW until you wanted to change exposure / brightness/ contrast etc. At that stage you would find that could actually (but only if you wanted to) alter the daylight / shade etc. colour balance, rather than have to frigg it using tone /hue / saturation controls.Andy Resnick said:This isn't something I'm going to argue about. They are more trouble for me, so I don't deal with that format.
Andy Resnick said:Here's something to consider- these two images (300%) may appear to have different levels of detail:
One reason is that our eyes are more sensitive to contrast at mid-range spatial frequencies, and so the cutoff frequency does not directly correlate with how 'good' the image 'looks'.
Borek said:I am not aware of any. Some cameras can save in jpg and tiff (that was the case of Marzena's Lumix) - but I never bothered to check the difference between these tiffs and jpg, and I can't don't have access to the camera now.
sophiecentaur said:I always wonder why different manufacturers have so many RAW formats /algorithms. Is it Licence issues?
Andy Resnick said:http://www.tiffen.com/filters.htm and http://www.hoyafilter.com/products/hoya/index.html have some specifically to address haze. Alternatively, you could get a longpass cut-off filter at nearly any wavelength you want:
http://www.edmundoptics.com/products/displayproduct.cfm?productID=2683
sophiecentaur said:From the look of the two graphs, it seems to me that the second picture could have had had some 'aperture correction' processing. The slope is increased and there is a slight ringing before and after. That is a common 'sharpening' method which accentuates edges and makes them more noticeable. In one dimension, it's achieved by a simple delay line filter to introduce a bit of hf boost. Point and shoot digital cameras have this built in, to some extent.
Andy Resnick said:I exclusively shoot JPG. I can see the compression artifacts on occasion, but so infrequently that I can't justify the added time and effort needed to deal with RAW.
Borek said:One the main reasons for using RAW - for me - is that they are much easier to correct later. Plus they save all 12 bits, so there is a little bit more room for mistakes.
sophiecentaur said:..., so I use it. You have no idea just how many iffy pictures you can rescue when they're in RAW.
Andy Resnick said:Both images are straight off the camera (original shot was in B&W), same aperture setting, etc. (manual focus lens). After capture, both images were treated the same- neither was sharpened.
Andre said:Maybe I can illustrate the advantage of 12 bits of RAW or more (wasn't it 14?) versus 8 bits JPG as hinted by Borek and Sophie.
Suppose that the metering tells you that this is the perfect exposure setting and that's what you save as jpg:
Obviously the dynamic range here exceeds what 8 bit jpg can reproduce. It won't help much if you increase or decrease the pitch"
You simply lost the information stored in the excess bits, but look what happens if you change the pitch in raw up or down:
See how much information was lost in the jpg.
Now you just need the software to HDR those three together.
Andy Resnick said:That's a different problem, one of excessive magnification- even a tack-sharp 35mm image will look horrible if enlarged to a poster-sized print and viewed close-up. That's why medium format cameras are used even for 8" x 10" magazine prints- the magnification is less.
Andre said:Maybe I can illustrate the advantage of 12 bits of RAW or more (wasn't it 14?) versus 8 bits JPG as hinted by Borek and Sophie.
<snip>
sophiecentaur said:And have a special shaped gradient filter for all occasions? I think you need to enter the 21st century, Andy. If you are interested enough to be discussing things at this level you can't justify sticking to jpegs. Pros use RAW for a good reason.
Andy Resnick said:Until you start posting photos you took, I'm not sure why I should take you seriously.
The techniques discussed here work best when full highlight and shadow detail have been captured by the camera sensor in Raw format.
sophiecentaur said:That's an interesting response. I can't recall, on any previous occasion, being asked, on PF, for personal experimental results, to justify a very reasonable opinion. Did you object to the, perhaps, cheeky wording of my last post. I'm sorry if you were but I thought these conversations were somewhat 'between friends'.
A few minutes on any Photograpy Forum will produce loads of opinions in favour of using Raw format and will provide you with plenty of examples of suitable software. If you have actually used one of the 'modern' image management applications then I would be amazed if you were to say you could tell the difference between the way they deal with Jpeg and Raw formats. If you haven't, then I suggest you give it a try. You will see what I mean.
Can there really be any doubt that data compression before processing cannot produce as good results as processing first and then compressing the data? A 'mechanical' form of pre-processing (a shaped filter mask) would clearly only be a partial solution to the problem of the contrast ratio of an original scene. I don't think you were really being serious, actually.
A few extra bits of quantising must contribute significantly to exposure latitude. Anyone who has used colour reversal film (slides) will know that what you had is what you get. You have nothing like the flexibility that colour negative film will give you. Cibachrome could produce absolutely stunning results - but only from a perfect positive transparency.
http://gallery.me.com/lyner" but not all of high technical quality, of course. Many of the earlier ones were shot in Jpeg.
Andre said:
Members are not required to conduct their own experiments to back up every claim. This is pretty mainstream stuff being discussed in this thread, not some outlandish claims along the lines of faster-than-light travel (just for example).Andy Resnick said:PF is a scientific forum- claims are supported or refuted with evidence, not by appeals to authority or anecdotal evidence.
Andy Resnick said:I'm not sure how to respond- I think you are mixing up concepts, or at least not understanding me.
I don't understand why you care so much about what I do.
I posted on this thread because I was directly asked a question.
Redbelly98 said:Members are not required to conduct their own experiments to back up every claim. This is pretty mainstream stuff being discussed in this thread, not some outlandish claims along the lines of faster-than-light travel (just for example).
sophiecentaur said:From the look of the two graphs, it seems to me that the second picture could have had had some 'aperture correction' processing. The slope is increased and there is a slight ringing before and after. That is a common 'sharpening' method which accentuates edges and makes them more noticeable. <snip>
sophiecentaur said:I<snip>Raw is the way forward for serious photography. Jpeg is the equivalent of the Instamatic, by comparison.
sophiecentaur said:<snip>If you are interested enough to be discussing things at this level you can't justify sticking to jpegs. Pros use RAW for a good reason.
sophiecentaur said:<snip>
sophiecentaur said:<snip>
sophiecentaur said:Yes, I have had mixed messages, I think. I am still not exactly sure which imaging method is referred to in some of your past posts. <snip>
sophiecentaur said:Yes, I have had mixed messages, I think.<snip>
Andy Resnick said:<snip>
You are free to use whatever tools you wish to create an image. Again, and I thought I was being clear about this, in my *personal experience* taking non-science images, I have no use for the RAW data format. *For me personally*, it's not worth the order of magnitude difference in file size or time required to sit and wait for the computer. *Personally*, I prefer to take photos rather than stare at a computer monitor. YMMV.
sophiecentaur said:Do you have a problem with people disagreeing with you in areas of your expertise?
<snip>