Photography
How Much Can RAW Really Fix Later?
How much can RAW really fix later? Its latitude is real, but only works on what the capture preserved: deferred decisions, estimates, and what never comes back.
Knowledge
Taking photos, running into problems, and keeping a record of what I tried.
About Knowledge
This is where I keep a record of the problems I've actually run into in the field, what I tried, and what I learned — so I don't forget. I'm sharing it as-is with anyone who might need it.
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Photography
What Decides the “Best” Image Quality in 2026?
Is the “best” image quality in 2026 a tripod, base ISO and f/8? A GH6 B0 print test taught me what a camera can deliver and what a photo needs differ.
Photography
Does a High-Megapixel Camera Need a High-Resolution Lens?
Lens and sensor aren’t two numbers where the smaller wins; they combine. What 47 MP showed me, what stars showed, and where “good for X megapixels” comes from.
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Photography
Did Digital Change What a Lens Needs to Do?
I thought a lens was still just a lens. Digital brought no wide angle, stripes against the light, a superb old 85mm, a failed 4×5 lens. What changed sat behind it.
Photography
Film Still Had Better Image Quality. I Bought the Nikon D1 Anyway.
In 1999 the Nikon D1 cost ¥650,000. I still thought well-printed film was better. Then my scan and a D1 file met on the same A4 office laser, and my path changed.
Photography
Where Was the Photograph Finished?
From one transparency came an exhibition print and a photo book; to me they did not look the same. Where was the photograph finished? 1990s sources and my path.
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Photography
27 articlesPhotography
How Much Can RAW Really Fix Later?
How much can RAW really fix later? Its latitude is real, but only works on what the capture preserved: deferred decisions, estimates, and what never comes back.
Photography
What Decides the “Best” Image Quality in 2026?
Is the “best” image quality in 2026 a tripod, base ISO and f/8? A GH6 B0 print test taught me what a camera can deliver and what a photo needs differ.
Photography
Does a High-Megapixel Camera Need a High-Resolution Lens?
Lens and sensor aren’t two numbers where the smaller wins; they combine. What 47 MP showed me, what stars showed, and where “good for X megapixels” comes from.
Photography
Did Digital Change What a Lens Needs to Do?
I thought a lens was still just a lens. Digital brought no wide angle, stripes against the light, a superb old 85mm, a failed 4×5 lens. What changed sat behind it.
Photography
Film Still Had Better Image Quality. I Bought the Nikon D1 Anyway.
In 1999 the Nikon D1 cost ¥650,000. I still thought well-printed film was better. Then my scan and a D1 file met on the same A4 office laser, and my path changed.
Photography
Where Was the Photograph Finished?
From one transparency came an exhibition print and a photo book; to me they did not look the same. Where was the photograph finished? 1990s sources and my path.
Photography
Was Large-Format Image Quality Just About the Lens?
Was large-format image quality just the lens? Ground glass, movements, film position, wind, dark slide — what 1980s manuals said to control, and my mistakes.
Photography
What Were Large-Format Lenses Designed For?
Did large-format lenses trade resolution for gradation? What the makers' catalogues actually sold, what f/22 meant, and what I looked at when choosing lenses.
Photography
Can You Really See a 0.03 mm Blur in a Print?
Once enlarged, a 0.03 mm blur is widened again by the printer and paper — an amount you can bound if the conditions are fixed. Whether a viewer sees it is not decided by the published data.
Photography
Why Was the Original Velvia Used as a “High-Quality” Film?
Why was the original Velvia used as a “high-quality” film? The sources show several choices; in my mountain-photography work it was almost one. Color, ISO 50, and Kodak.
Photography
Why Do Star Trails Show Seams Even Though the Frames Were Shot Continuously?
Why do Lighten-stacked star trails show seams and dashes even though the frames were shot continuously? I re-measured 3,522 Nikon D3 NEF files from 17 years ago. The gaps between frames alone could not explain it; the star's measured brightness was already fluctuating before compositing, and Lighten selected and amplified it. Cause and period remain unknown.
Photography
What Did “Rich Gradation” in Film Really Mean?
“Rich gradation” in film was not dynamic range, and not bit depth. The Japanese word carried several questions at once. From what I saw in new leaves and fresh snow on transparencies in the 1990s, and from the technical literature, here is what it meant.
Photography
A 30-Minute Exposure vs. 30 Minutes of Lighten Compositing: What Actually Differs?
The star is just as bright either way, so why does one 30-minute exposure look different from sixty 30 s frames stacked with Lighten? A star image drifts across the sensor; in my Nikon D3 data, one pixel receives starlight for only about 30 seconds of the 30 minutes.
Photography
How Many Megapixels Is 4×5 Film? Why There Is No Single Answer
How many megapixels is 4×5 film? There is no single answer. The same Velvia data sheet lists 80 and 160 lines/mm depending on test contrast — four times apart as a cell count. Comparison is possible once the conditions are set, but not as one number. I bought a 4×5 in 1990 and shot Velvia.
Photography
Is a Lens Really at Its Best 2–3 Stops Down?
Is a lens really at its best 2–3 stops down from wide open? The same “2–3 stops” means f/2.4–f/3.4 on an f/1.2 lens and f/11–f/16 on an f/5.6 lens. In the measured examples I checked, the best-performing aperture scattered from near wide open to nearly five stops down. A useful rule of thumb — not a law, and not the aperture your photograph needs.
Photography
Does Lower ISO Really Mean Better Image Quality?
Does lower ISO really mean better image quality? Not always. When lowering the ISO lets you collect more light with a longer shutter speed, the picture can get better — but what made it better was the light, not the low number. Lowering only the ISO number is a different thing, and expanded settings like ISO 50 have a trap of their own. From a photographer who starts every shoot at ISO 100 and f/8.
Photography
Does Raising ISO Really Increase Noise?
Does raising ISO really increase noise? With the same light, raising only the ISO does not add to the noise the light itself carries. The main reason the noise stood out was the small amount of light; ISO made it easier to see, and the rest depends on the camera's design. A photographer who shoots star landscapes at ISO 12800 re-examines a piece of common sense.
Photography
What Is Your Circle of Confusion?
The 0.03 mm circle of confusion is not a physical constant. It compresses viewing conditions — output size, viewing distance and an acceptable angle of blur — into one number. I used 0.03 for more than 25 years without asking what it assumed; here is what I found, and which conditions you need to declare to find your own.
Photography
Is f/8 Really the “Best” Aperture?
Is f/8 really the best aperture? About 50 years after my father told me to “shoot at f/8,” I revisited the rule through optical theory, real-lens measurements and an aberration model. I found no evidence for a universal f/8 — yet I still use it when I have no reason to choose otherwise.
Photography
When Did My "8 Seconds" for Freezing Stars Become Outdated?
How many seconds should you expose for astrophotography? Since my Nikon D3 days I have used 8 seconds at around 15mm for nearly 20 years. I re-examine that 8 seconds through the 500 Rule, the NPF Rule and higher-resolution sensors. This is not an article recommending 8 seconds.
Photography
How to Focus on Stars in Astrophotography: Where and How to Set Focus Correctly
Learn how to focus on stars for astrophotography. Discover when to use starry sky AF, manual focus techniques, and why the infinity mark isn't always reliable for sharp star images.
Photography
Astrotracer ④: How Did I Calculate Astrotracer Tracking Error? — From the Rotating Sky to Star Motion on the Sensor
What exactly is the "tracking residual of N px" used in the first three articles? I open up the whole calculation — grid points on the sensor, inverse projection to the sky, rotating the Earth, reprojection, following with X/Y shift plus rotation, and measuring what is left — including how AI was used.
Photography
Astrotracer ③: Why Do Stars Still Trail Near the Edges with an Ultra-Wide Lens? — Sensor-Shift Tracking Is Not an Equatorial Mount
The stars are held at the center of the frame but trail near the edges. I had assumed for years that it was "because it is a fisheye." Recalculating from the rotating celestial sphere, the lens projection and the rigid motion of the image sensor gave the opposite of what I expected.
Photography
Astrotracer ②: How Long Should You Track the Stars? — The Maximum Tracking Time Is Not the Exposure You Want for a Star-Landscape
The manufacturer's tracking time is not a guarantee that the stars will stay points. This article separates four different limits — the mechanism, tracking accuracy, ground blur and stars near the frame edges — and works out ground blur by focal length, and how it relates to the 500 rule.
Photography
Astrotracer ①: Why Do the Stars Stay Sharp While the Ground Blurs? — How Sensor-Shift Tracking Works
Track the stars and the ground blurs. That is not unique to Astrotracer — an equatorial mount does the same thing. Here is how PENTAX moves the image sensor in X, Y and rotation to follow the stars, and where the ground actually blurs in the frame, based on official documents, patents and an idealized geometric model.
Photography
Coastal and Water Photography: Shooting Techniques for Compelling Images
Master coastal photography techniques including ICM, long exposure, and silhouettes. Learn how to apply these methods to everyday subjects and create impactful monochrome images.
Photography
Complete Guide to Astrophotography Camera Settings and Equipment: From Exposure Fundamentals to Essential Gear
Master astrophotography exposure settings, essential equipment, and pre-shoot preparation. Learn exposure principles, lens requirements, and best practices for capturing the night sky.
Photoshop
3 articlesPhotoshop
5 Essential Considerations for Portrait Retouching
Master portrait retouching with these 5 key techniques: preserving skin texture, enhancing eyes, color grading, background processing, and composition refinement.
Photoshop
Photoshop Lab Color Mode Retouching: Master the L, a, and b Channels
Learn how to use Photoshop's Lab Color mode to separate luminosity from color information. Discover techniques for skin retouching, landscape enhancement, and professional color correction that go beyond RGB adjustments.
Photoshop
Dodge and Burn Retouching Fundamentals: Creating Even Light with a 50% Gray Layer
Master dodge and burn retouching using a 50% gray overlay layer. Learn brush settings, selection techniques, and Lab color methods to add even, natural lighting to portraits and landscapes without streaking.
Sidekick
1 articlesSidekick
What to Check When Sidekick Star's AI Mask Generation Won't Finish
Sidekick Star's AI mask generation can appear to stall without ever completing. Here is what is actually happening, what you can try, and the improvements made on the development side.
Marketing
2 articlesMarketing
What Makes Photos Stand Out on 1X.com: Genre-Specific Retouching Trends
Discover the common elements that get photos featured and awarded on 1X.com. Learn genre-specific retouching strategies for portrait, landscape, astro, and monochrome photography.
Marketing
How to Sell Photography Knowledge on note: From Account Setup to Pricing Strategy
Learn how to monetize your photography and retouching expertise on note, from creating an account to implementing tiered pricing strategies and membership programs.