It looks WB was 5691K “as shot”.
The rocks looked too green to my eye so I dropped a colour picker on the rock and changed the temp globally. I probably should have done that with a local adjustment.
Thanks.
With respect to the colour space, I’d noticed I got a lot of out of gamut warnings on other pics I’d processed in DxO last week when on Wide Gamut. I did some reading here on many threads about colour space, but it was mostly above my head and I came away little the wiser, hence decided to keep things simple going forward.
I use TrueDoF-Pro to calculate things like hyperfocal distance, taking into account diffraction.
As a rule of thumb, the blur spot diameter should be twice the pixel pitch, which would make it 7µm. And that is regardless of sensor size ratio.
Entering 7µm into TrueDoF-Pro, for a focal length of 19mm, gives a hyperfocal distance of 19.7 metres with a closest sharp distance of 9.86 metres and a minimum aperture of f/3.5. To my mind, this is impractical.
Setting the blur dot size to 10µm really doesn’t help that much, giving a closest distance of 4.85m at an aperture of f/5.
For my 46Mpx Nikon D850, I tend to calculate for 20µm, which gives a closest distance of 1.22m at 19mm with an aperture of f/10 without diffraction.
Personally, I think f/5.6 would be too restrictive on DoF and so, I would try f/10, although, I can’t really see enough diffraction to worry about f/11.
I could agree with that. I had simply “neutralised” it to 0 along with the temperature to 5600.
Correct.
Well, to put it bluntly - get it! You’ll be amazed at the difference it can make and it is so much more controlled and refined than ClearViewPlus, which I would never use, or micro-contrast.
Yes, but your version changed that to 4940K, which was definitely a tad on the “hazy” side.
Which profile were you proofing to?
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Keep in mind that OM-5 has 17.3 x 13mm sensor.
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Which has almost the same pixel pitch as my D850 full frame and it is “blur spot diameter” (previously known as CoC) which determines diffraction more than equivalent focal length.
My theory is that light reflections from the grass got scattered by slightly foggy air, producing green cast in some parts of picture, which you can “fix” by magenta tint. But there might be some other reasons…
Size of circle of confusion must take into account lot of parameters.
2 of them not directly related to the gear used are the size of the final image and the distance of the observer to the image.
So …
(From my early days as a second camera operator).
EDIT : circle of confusion is used to evaluate depht of field.
Yes. I should have created a virtual copy like Joanna did.
I’ve just selected everything except the foreground. I prefer playing with contrast and black point rather than using Clearview because Clearview, most of the time, changes the colors, much more than highlights/mid tones/lowlights and blacks (I don’t know the words they use in English for these 4 tunings, I’m French, nobody’s perfect
).
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I’ve checked the folder of shots I was working on and it looks like I didn’t have soft-proofing on. Changing the colour space now to Wide Gamut shows out of range warning for the monitor and soft-proofing as sRGB, with the soft proofing out of range warning disappearing on the other soft-proofing options. My monitor is a 15 yr old Dell that apparently had a wide gamut at the time, described as being 102% of NTSC. No idea how that translates to sRGB, Adobe RGB etc.
The “collective” dop-file P7280021.ORF.dop (653,2 KB) presents …
There were 2 white framed versions that looked the same and I kept the second one.
Reading that you don’t have FP yet …
In the yellow virtual copy I’ve used the Luminosity mask \ Brush.
The shown foreground mask excludes rocks, bright grass and heather flowers.
But I doubt you will see them without FP – sorry for that.
now – see PM from August 1st, where I replaced the Luma masks…
It’s an old gamut not not really centered on current gamuts.
it covers about 90% srgb, 91% adobe rgb, 82% dci p3.
The first diagram on this page:
lets you see how NTSC compares to sRGB and Adobe RGB.
Blur spot diameter is not the same as CoC.
The blur spot diameter is a physical concept, the CoC is a users concept.
For printing one can say that diffraction is becoming visible when the blur spot is larger as the max CoC. And that depends on the print size you use.
For viewing 100% PhotPills uses a ratio of 2.5. Diffraction becomes visible when the blur spot is 2.5 times the pixel size.
The sensor dimensions are incorporated into the coc, 0.03 for FF and 0.02 for DX.
The blur spot is only dependent of the f-nr.
George
Agreed. Which is why I use a blur spot of 20µm, as a compromise between perfect, diffraction free, sharpness and the old-fashioned CoC based on sensor size.
Take a look at the writings of George Douvos. he is the author of TrueDoF-Pro, which I use regularly.
Especially interesting is this article which discusses high resolution sensors
According to TrueDoF-Pro, for ultimate diffraction-free rendering, the advice is to use twice the pixel pitch for the minimum possible blur spot, instead of 30µm, as in the old film days. In other words, for my 46Mpx Nikon D850, that means 10µm.
Unfortunately, that advice can be very unrealistic if I want anything like hyperfocal DoF for landscapes, because it yields a minimum aperture of f/5, which is severely restrictive as, for a 28mm focal length, it limits a nearest “acceptably sharp” distance to 10.5m.
But, if I compromise by using 20µm, I can then rely on a minimum aperture of f/10 to give me a nearest “acceptably sharp” distance of 2.68m, which usually means a DoF from almost in front of me to infinity for the same focal length.
I realise this seems to go against conventional wisdom, but 30µm was calculated many years ago, before digital, and which relied on emulsion grain size.
All I can say is, I am getting comments on my A2-sized prints from other “old-time” photographers, examining them with a magnifying glass, who are convinced they must have been taken with a large format camera - such is the sharpness and lack of diffraction.
Truth be told, I am finding less and less use for my 5" x 4" LF camera these days as, with scanning, I get a file that will print to 127cm x 102cm without interpolation and, with a my Nikon; I get a file that will print to 87cm x 58cm without interpolation but, by using something like Topaz Gigapixel, that is easily doubled to 174cm x 116cm. and I defy anyone to tell the difference in quality.
The only use I can now see for LF is when I need to use tilt and shift, or to create a wall-sized print.
No. It’s based on what a human can see at an arm length distance. I mean he can distinguish between a point and a circle. That maximum size of that point is the basic behind the idea of max CoC.
If you want to print a size that’s 10 times linear your sensor size, than that max coc is 1/10 of that point. On the other hand one can say that I’ve to magnify the sensorsize 8.3 times to print a A4 print. About.
If I calculate with a CoC of 0.03 then that visible point on your print will become 12*0.03=0.249mm. And that is the max size for us to see a dot as a sharp point and not as a circle. It’s not hard science.
George
The average human visual acuity is 1/1500 radian.
So, when you look at an A4 print from a distance that allows you to see it in its entirety (around 36 cm), it allows you to distinguish two details separated by 360/1,500 = 0.24 mm.
And if you could look at a 24 x 36 mm negative, from 42 mm distance (in order to fill your field of view with the picture) you get 28 µm which is roughly the size of the CoC.
Some take 1/1750 but anyway, it’s just an average value, meaning it depends how good is the visual acuity (e.g. old / young) is the person that looks at the photo etc.
That’s the same as what I calculated.
But what I wanted to say, the CoC is not based on emulsion grain size. It’s an optic item.
George
Yes, it was just another way to explain the result: nothing to do with emulsion grain or pixel size. Just average human visual acuity.
That’s all well and good, but now we have high resolution sensors, which are capable of resolving more detail - thus the move to blur spot diameter, based on pixel pitch, which changes things. Did you read George Douvos’ articles?
I have to know this stuff because I print to A2 and larger and need every bit of sharpness possible.
What I’m writing doesn’t depend on some theoretical and outdated calculation - it comes from real world experience of folks seeing my large prints, from up close, and not seeing diffraction on small details.
Surely you, as a photographer, have been to an exhibition and the first thing you do is put your face as close as possible to a print to see if it meets your critical standards of sharpness?
Well, at a CoC of 30µm, you would be disappointed but, with my prints, you would be gobsmacked at the detail…
The smaller the sensels, the more sensible for diffraction and/or unsharp images.
I did read the article though I didn’t spell it. He’s using an example of the D800, 2 sensels together with the size of 10 microns. His story, as far I can say, is just explaing the DOF.
Look at the Diffraction Calculator of PhotoPills https://www.photopills.com/calculators/diffraction. He’s using a calculator for 100% on screen related to 2.5 the sensel size and a calculator for printing related to the CoC.
I remember when the D800 was introduced there was an article from Nikon that warned that this camera needs pro-lenses due to its sensel size. Also it was much more sensitive to CA and the exposure time had to be chosen shorter. All due to its smaller sensels or higher resolution.
No, that’s the last thing I do. I do it, but surely isn’t the first thing.
From George Douvos.
His used max CoC, which he calls blur spot diameter are just the regular CoC. Yes, you can set it to any size. But setting it at a lower size as beeing standard only means you want to be more critical.
But reading and reading again his article I think he mixes up the difference between blur size and dof. And the D800 is more sensitive to faults.
I’ll let you know later.
George