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Forum: Digital Processing, Software, and Printing
22 Hours Ago
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Film may be a good idea for archival storage.
Although it would seem like properly encoded and stored digital storage media (i'd not trust SSDs or modern high-density magnetic media) would be the best choice for archiving images, they suffer from obsolescence of the reader equipment. Not many people have ways to read old floppies, Zip disks, Compact Flash cards, or SCSI disks any more. (Note: I think I do these things in my basement of old tech but given that's I haven't tested them lately, I might be wrong). In theory, one could carefully transfer every collected archive image from one generation of digital storage to the next, but will people always do that? And what happens when the makers of Photoshop 2050 decide it's not worth including the compatibility files for reading DNGs from the 2020s?
Film (if properly stored!) has the advantage that is can ALWAYS readable by the human eye and can even be redigitized by whatever camera du jour.
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Forum: Digital Processing, Software, and Printing
2 Days Ago
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The key is finding a good high-resolution display such as a 4k HDR monitor. You want the blackest possible blacks. Even with that, the tonal range of the display image (10 bits?) with be less than the range of both of the RAW and of the film.
The other gotcha would be reflections off the display of the room (illuminated by the displayed image) and the front of the camera. A good matte black hood over the display with a hole the size of the front element will prevent unwanted ghostly reflections. (Note: a polarizing filter is unlikely to help much given the imaging geometry.)
There might also be some tricks to finding the best film emulsion to couple properly with the spectral output of the RGB pixels of the display otherwise the colors could be shifted or desaturated.
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Forum: General Photography
3 Days Ago
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My only additional comment is that the solution depends on exactly WHY the film renders the way it does because that affects whether you:
1) put a color filter in front of the lens,
2) put a color filter in the scanner or darkroom enlarger, or
3) tweak some digital value of the scan file.
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Forum: General Photography
5 Days Ago
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Hmmm.... This sounds like a deeper issue because it is also affected by the color dyes in the film, the color filters if you use a scanner, and the color properties of the output display, printer, or color paper.
Exactly WHERE are you viewing the scene that renders foliage as injection-molded green and what steps do you take to get from outdoor scenery to indoor imagery?
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Forum: Repairs and Warranty Service
5 Days Ago
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It might be a hole in the shutter curtain near the left side of the lower edge of the film gate.
If the leak shows up in the sprocket zone of the film, then its probably in the back.
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Forum: Photographic Industry and Professionals
5 Days Ago
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The diversity (and divergence) of comments on this thread show that maybe the original question of the thread rests on a false premise. Perhaps the industry has not lost its way because there is no one way to go.
Some people want more and more resolution while others find a 10 MPix K10D to be adequate (with more pixels just being more of a burden).
Some people want the fastest AF and frame rates while others revel in the enforced delays and constraints of a slower camera.
Some people love the complexity of all the modes of metering, AF, white balance, digital filters, and time lapse controls while others seek simple elegance.
Some people pixel peep and demand corner-to-corner micro-contrast perfection from every lens while others eschew clinical perfection for evocative form and tonality.
Under such conditions no single camera or lens can ever grab everyone's attention or lead the photographic world into the future. And that is because "the future" is not a single destination, it is an ever enlarging world of choices in styles and approaches to photography that foster a diverging range of equipment.
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Forum: Photographic Industry and Professionals
6 Days Ago
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First, inventions are not like hamburgers -- they can't be cranked out on an assembly line day-after-day, year-after-year. Once something is invented, it can't be invented again. Each new invention permanently consumes some chunk of the space of all possible inventions. Sensor technology is near the limits of what silicon sensors can provide. Maybe some exotic new sensor technology (and Foveon ain't it) will eek another stop of dynamic range out of the light levels on this planet but maybe not. Physics places an upper bound on basic camera performance.
Second, many of the more recent inventions (extremes in framerates, video, global shutter) arguably only appeal to a niche audience and might actually turn-off some buyers. Sure, the breathless yammering of influencers and pundits tries to make each new feature a must-have, game-changer disruption of the entire industry. But the truth is that most inventions only bump the needle a little bit (and sometimes in the wrong direction like Sony's global shutter A9). Meanwhile, all of the pre-existing cameras ever built still continue to take decent pictures. The point is that each new invention is both even harder to create and even less likely to capture everyone's interest.
Interest in photography has not waned at all. I'd bet that the number of people taking photographs and the number of photographs taken per person continues to rise. It's just that more and more photographs are taken with smartphones. My wife's iPhone 14 Pro is essentially identical to interchangeable lens camera with a bag of three decent lenses (12, 24, and 75mm equivalent focal lengths). Sure, my Pentax cameras offer much more photographic control, a much wider array of lenses, and better resolution and image quality. But the iPhone takes very acceptable pictures under a wide range conditions. (The ratio of smartphone pictures to "real camera"pictures is nothing new -- I'd bet consumer point-and-shoot camera have always dominated the picture-per-year figures.)
There's also a strong segment of photographers (both established professionals and neophytes) who clamor for simpler cameras, not ones with more and more features. They actually want cameras that provide a more direct experience stripped of all the automagical bells, whistles, and shiny bits of technology that were added only for the sake of claiming the camera has more technology. A key part of that segment is in having more focused cameras that do something especially well rather than trying to do everything for everyone.
Personally, I think Pentax/Ricoh are doing alright in this era of over saturation of technology, especially given their limited resources. The monochrome K3 and forthcoming half-frame film camera epitomize the kinds of new products that are more interesting to actual customers. Rather than bloated technological flagships, maybe it's better to create nice sailboats that put the creativity of photography back in the hands of the photographer.
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Forum: Pentax K-3 III
04-15-2024, 08:48 AM
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A .bin file is a binary file. There are apps that can read and display such files but the results are unlikely to be easily human readable. Instead the displayed file would be shown in binary, octal, or hexadecimal code. Most likely, specific bits in the file correspond to specific settings in the camera.
Someone with good computer skills in assembly language programming (and a lot of time on their hands) could probably figure out the structure of the K3III's .bin file. Carefully comparing .bin files while making small changes to the settings would likely reveal which bits or codes in the .bin file correspond to which menus and settings on the camera.
Perhaps someone has already documented the structure of the K3III's .bin file.
Good luck!
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Forum: General Photography
04-05-2024, 01:18 PM
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Back story: found this camera whilst beachcombing.
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Forum: General Photography
04-05-2024, 01:16 PM
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A 10310mm f/1.23 lens and a 2 pixel circle of confusion on the LSST camera has a hyperfocal distance of over 4km so LEO and MEO objects might be a tad blurry.
The trickier issue is the depth of focus. How much can be lens-to-sensor distance vary without blurring the image by focusing too far away from infinity? That turns out to be only ±25 microns which is pretty tight for an optical assembly and path that many meters in size.
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Forum: General Photography
04-04-2024, 05:45 AM
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I want the lens! It's a 10,310 mm f/1.23!
The camera seems to have an 734 mm image circle giving it a crop factor of 1/17 relative to "full frame."
If you want to play the equivalence game, the lens is a 600mm f/0.07.
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Forum: Pentax News and Rumors
04-03-2024, 05:46 AM
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The K-3 name on the joke announcement seems to be confusing people. This joke was NOT a full frame version of the much-loved K-3.
The joke (one April 1, 2012) came out a year and half BEFORE the K-3 (announced 7 October 2013.) and four years BEFORE the K-1 (announced February 5, 2016).
The joke was meant be Pentax' first full frame camera but the pranksters named it the K-3 which fit model number progression at the time.
The extreme interest in the camera reflected Pentaxians' interest in a full frame camera.
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Forum: General Photography
03-31-2024, 10:12 AM
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First, the more you plan out your shots, the more you will be able to do as well as having time to enjoy the experience.
Your overall plan and equipment roster looks good: one camera focused on the sun and corona while others take wider angle shots of the experience.
Telephoto choice: you might want to test the sharpness of your copies of these lenses yourself on either the sun or moon. That practice will also help you learn: 1) the IQ of your lenses & teleconverter; 2) how to get and keep infinity focus; 2) how much these celestial bodies move over full duration of pre-eclipse to post-eclipse shooting; 3) how to deftly handle the heavy lens, camera, and tripod.
Wider shots: Find out the angular elevation of the sun during the eclipse at your chosen location to help plan the best focal length for shots that encompass the corona, sky, horizon, and landscape. If you multiply the elevation angle of the sun by 1.5X, you get the required lens angle of view for a shot that is 1/6th landscape, 2/3rd horizon and sky below the sun, and 1/6th sky above the sun. A 2X factor provides 1/3rd landscape, 1/3rd horizon+lower sky, 1/3rd upper sky but that may be too wide unless you do a panoramic crop. You might think about both portrait and landscape orientation variants of these shots.
Time Lapse: You might also set up a time lapse camera with a wide angle lens (the GR or a smartphone?) positioned to see you, your equipment, and the eclipse that you run for the minutes or even hours before, during, and after the eclipse - it can create a fun time lapse movie of your experience.
Other lenses: The only missing bit of gear might be a wider-angle lens for K-1. Depending on how high the sun is, you might need a full-frame lens wider than 24mm to get good landscape+eclipse images.
Other gear: A count-down timer with an alarm can help you keep track of time, especially to be ready for the reappearance of Baily's beads or diamond ring effects at the end of totality.
Have a wonderful time!
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Forum: Photographic Technique
03-31-2024, 05:56 AM
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To the best of my knowledge, the sun itself does not have an interesting features in the IR. The sun is mostly a blackbody radiator in the IR with some featureless attenuation due to gases in the atmosphere. An IR image of the partially eclipsed sun would not look any different than the visible light version of the sun.
What might be interesting are IR images that combine IR-interesting foliage or subject matter with the strange crescent-shaped dapples of sunlight that come through that foliage during the partial eclipse. A wide angle shot that has a nice view of the strange dappled shadows cast by a tree plus the tree's leaves (or other trees/shrubs in the background) might be quite otherworldly. Finding the right conditions and subject matter might be difficult during the event but you can scout out possibilities in the days before with shots taken at the same time of day as the eclipse.
You could even make your own crescent dapple generator with a large piece of cardboard or paper that has a pattern of small holes. That pattern could have a shape (a heart, circle, square, monogram letters, etc.), be a perfect grid, or something more random and organic. You could take IR portraits of people with crescent dapples on their faces. To get the dapple to be a certain diameter, the holey cardboard needs to be about 100 times the distance from the subject (in the direction of the sun) as the desired dapple size. For example, making 1/2" dapples means holding the cardboard about 50" from the subject. You can experiment with this concept in the days before. The only things that will be different during the partial eclipse is that the dapples will be crescents (not circles) and the contrast between the dapples and the shadowed area will increase (the light levels in the dapple during the partial eclipse will be the same as during full sun but the shadows will be darker.)
Have fun!
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Forum: General Photography
03-30-2024, 04:57 AM
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Forum: Flashes, Lighting, and Studio
03-27-2024, 03:21 PM
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The best way to think about this is that EC is the way the photographer tells the exposure system that the subject is NOT the proverbial 18% gray. Bright subjects need positive EC to increase the exposure. Dark subjects need negative EC to decrease the exposure.
Even if the subject matter is 18% gray, EC can be used for highkey or lowkey effects that intentionally over- or under-expose the subject for artistic purposes.
In the case of fill flash, different ambient and flash EC settings may be needed if the ambient-lit background and flashed foreground have very different tonalities (e.g., a black cat in front of a bright white backdrop) of if the photographer wants to enforce some level of over- or under-exposure for the two elements of the scene.
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Forum: Pentax News and Rumors
03-27-2024, 09:31 AM
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None of the options fit. I'm not an early adopter of updates, not a strict schedule updater, but I'm not a "never updater." My poll option would be:
"I occasionally update the firmware."
I probably miss most updates because I was not paying attention. When I do update, it might sometimes be when it fixes a problem or adds a nice feature. Or it might be at some random time when I think about it and check for new firmware.
Although I've never had a problem with a firmware update, I never ever update the firmware before a big trip. Because of that policy, I sometimes download new firmware but don't take the time to update before the next version appears.
P.S. By contrast, I'm much more cautious about updating applications and operating systems on phones, tablets, and computers (except for security updates). I've had too many experiences where the updated version was far worse than the original version -- slower performance, features removed, backward file compatibility removed, etc. Operating system upgrades are the worst -- they often make obnoxious, productivity-damaging changes with the added problem of forcing updates to applications that bring more problems.
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Forum: General Photography
03-25-2024, 08:15 AM
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Should photography be quick and effortless or should it take lots of time and concentration??? That depends!
Sometimes, for some people, photography should be quick and effortless:
For a pro photographer, especially an event photographer, the faster they can get the job done (and done well), the better. I'm sure the average bride, groom, and wedding party guest surely appreciates a photographer who quickly gets all the necessary and serendipitous shots without monopolizing everyone's time at the event. And a fashion, product, portrait, or industrial photographer who can work fast can take on more projects per month and can save their client money.
However, for some other people, photography should take lots of time and concentration:
Photography can be an wonderful passtime. But photography is only a great passtime if it takes time. Many of the best hobbies (painting, wood working, restoring old stuff, etc.) bring satisfaction by requiring laborious mastery of a complex, technical, and artistic process. Would people like jigsaw puzzles if they automagically self-assembled on the table at the click of button? Probably not. Some people feel that way about photography -- they want to take a long time to put all the pieces together: equipment choice, composition, lighting, exposure, timing, post processing, etc.
And, ironically some of the best "fleeting moment" pictures can require dozens of hours of time. I know some landscape photographers who literally invest hours, even dozens of hours, repeatedly traveling and hiking to the same scenic location until they get the perfect confluence of sunrise, sunset, foliage, or weather.
Thus, each person must decide if they want emphasize efficient production of an outcome (the photograph) or satisfying experience of a process (photography). The answer to that question will drive them in markedly different directions on the time and labor requirements of each image.
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Forum: Pentax News and Rumors
03-24-2024, 03:42 PM
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If that ND filter does not block enough IR, the sun can still burn the aperture blades, shutter, and anything black in the mirror box. Also, I looked up the transmission for a Hoya UV/IR cut filter (HOYA | UV&IR Cut) and found that it only blocks IR in the range that silicon can see. IR beyond about 1100nm passes through so some longer wave IR (maybe about 5-10% the full solar value would get to the sensor).
Indeed! I also take sunrise telephotos without problems but that is when the sun is heavily filtered by haze and atmosphere and within EV 18 max value of the camera's light meter. When the sun is high in a clear sky, it's EV value is probably around 32.
A quickie test is to put the filter on your telephoto lens (with no body and the aperture held open), point it at the sun, and pass your hand quickly behind the lens at about the film plane distance. If you feel nothing, pass it slower. If you still feel nothing, then let it sit a bit.
It is true that all I've said assumes a worst case scenario -- a filter that is transparent to IR. In reality, you'll probably be fine. That ND filter won't be totally transparent in IR. It probably will block a significant fraction of the sun's energy. And the UV/IR filter will reflect a good chunk of any IR that gets in. But......
P.S. Old Style NDs, IRNDs, and Everything in Between ? Kolari Vision had some interesting information about the IR performance of "old style ND" filters. It definitely showed that ND filters don't block IR as well as they block visible light. But they are no where near being transparent to IR. An old style OD 4.0 filter (blocking about 13 stops of visible light) was 4 stops brighter in IR. That's enough to really affect the exposure calculation but that's still a decent 9 stops of attenuation of energy.
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Forum: Pentax News and Rumors
03-24-2024, 11:11 AM
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YIPES!
If the filter truly lacks any attenuation in the IR, then the net effect is a filter with only about 1 stop of attenuation of the sun's energy.
This Lens Rentals Blog post provides nasty examples of what the sun can do to the insides of lenses, aperture irises, mirrors, shutters, and sensors.
This is why ALL solar filters should be at the front of the optical system -- limiting the total energy that enters the lens. Filtering at the sensor or eyepiece cannot prevent damage inside the optical system.
In theory, the IR/UV filter might protect the sensor, but not the shutter, mirror, mirrorbox, or lens. Moreover, most IR/UV filters use a thin-film coating to reflect the unwanted light. They don't get rid of the energy, just bounce it elsewhere. And if the lens is not pointed perfectly at the sun or you are on a planet that is spinning so that the image of the sun moves out of the frame, then the blazing IR solar spot can move on to all the black bits inside the camera.
You might be able to test your filter (at your own risk!) Position a magnifying glass in the full sun in a fireproof area so that it burns anything placed at focal point on the ground below it. Add the candidate filter, put a sacrificial bit of black plastic in the focal point, and see what happens. If the plastic burns, melts, or gets warm, the filter is not blocking enough IR and the filter fails the test. If it passes this test, the filter might be safe for short periods of use but I'd still not look through the eyepiece!
Have fun (but be careful!)
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Forum: General Photography
03-24-2024, 08:51 AM
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Traveling with non-photographers does require some adaptation:
When hiking with a group of non-photographers, I've learned to hike fast to reach anticipated overlooks, photogenic streams, flowery meadows, etc. And they've learned that they can pass me and that I'll catch up. I'll also snack heavily on the trail so that when the group stops for lunch (typically at a scenic spot), I don't need to eat and can use that time to compose and make photos.
My wife is fairly tolerant of photographic pauses but sometimes it's better to agree to each go at our own pace and each tarry at our own respective attractions. We'll agree to meet at some specific point and time. These days, various apps (e.g., Apple's built-in "Find My" app) make it easy for a couple (or a group) to track each other's locations and find each other.
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Forum: Pentax News and Rumors
03-22-2024, 08:05 AM
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Please make sure you measure the density in IR because that accounts from almost half the sun's high-intensity output.
The filter's darkness in visible light is no guarantee of safety. For example, fully-exposed and developed color negative film looks extremely opaque but it is transparent in IR. The human eyeball has no way to sense damaging levels of IR so it's possible to be permanently blinded with the wrong filter material.
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Forum: Pentax SLR Lens Discussion
03-22-2024, 07:35 AM
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Here are two bits of knowledge about lenses and astrophotography to keep in mind:
1) The effects of focal length on star brightness:
Most people know that the overall photographic brightness of the extended objects in the scene (i.e., subjects such as the canyon wall, sky glow, moon, nebula, etc.) is a function of the numerical aperture. Images of extended objects with a f/1.4 lens are 2-stops brighter than images of the same subject taken at f/2.8. A f/1.4 lens lets you shoot with 1/4 the total shutter time or 1/4 the ISO setting compared to a f/2.8 lens.
In contrast, the photographic brightness of a point object (e.g., a star) is a function of the physical aperture which is the product of the numerical aperture multiplied by the focal length. A 14/2.8 lens has a physical aperture of 5mm. A 35/1.4 has a physical aperture of 25mm. That's 5X the diameter which is 25X the light collecting area which makes the stars 4.6 stops brighter. (This is why telescope optics are primarily defined by their physical aperture, not the numerical aperture. The James Webb Space Telescope has a seemly pathetic f/20 numerical aperture but that's less important than 6.5 meter physical aperture of the mirror.) With the 35/1.4, you'll see a lot more stars and they will be a lot brighter compared to any sky glow, nebulosity, or the foreground canyons.
2) The effects of focal length on astrotracer:
Astrotracer shifts the sensor in an attempt to follow the motion of the stars in the sky. However, the sensor shift is in the rectilinear coordinate system of the imaging lens while the sky moves in a spherical coordinate system. For longer focal length lenses, the moving spherical coordinate system of the sky is fairly accurately handled by the rectilinear motion of the sensor. However, short focal length lenses will show trailing of stars, especially in the corners. If you are using Astrotracer and need longer shutter times, you might be better off with a longer lens. The alternative is to buy a tracking mount which can move the whole camera-and-lens to follow the curving arc of the celestial sphere.
Overall, you may find that the 35/1.4 delivers better images albeit at the significant cost of having to shoot a bunch of tiles in order to get a wide enough angular field of view to show more of the canyon and Milky Way.
Have a great time!
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Forum: Pentax News and Rumors
03-20-2024, 05:39 AM
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I bought a large sheet of Thousand Oaks solar filter material and made filters for: 49mm, 52mm, 58mm, 77mm, 5" telescope, and a pair of filters for my Pentax binoculars. The camera lens filters use the screw-in rings scavenged old de-glassed skylight/haze filters. The telescope and binocular filters have cardboard frames with tensioned ring of rubber bands to ensure that the filters grip the optics but can be removed during totality.
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