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#136
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film vs CMOS
On Sun, 12 Aug 2018 00:54:04 +0800, "Mr. Man-wai Chang"
wrote: On 8/12/2018 12:50 AM, nospam wrote: In article , Mr. Man-wai Chang wrote: But how do you get a 100% TRUE lossless original? Using good, old film-based cameras? film is more lossy than digital. I don't know much about photography films. And you might need to talk about the size (length x width) as well as the resolution of the senors and films! But isn't film molecular level? Not really. A film image is constructed of crystaline grains which are far above molecules in size. -- Regards, Eric Stevens |
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#137
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Is VLC 3.0.3 for Windows 7?
"Paul" wrote:
Apd wrote: The term "bitmap" in computing doesn't only refer to picture image data. For example, the Mac file system: [..] But this reference has nothing to do with images, Yes, that's what I said. so we cannot become concerned about whether it should be bitmap or pixmap. I was giving another use of the term "bitmap" since this part of the thread is about definitions. I said nothing about pixmaps. |
#138
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Is VLC 3.0.3 for Windows 7?
In article , Wolf K
wrote: Well, he was just dim, if he didn't realise that a JPEG_is_ a bitmap. it isn't. jpeg is a compressed file format True. yep. which has nothing whatsoever to do with bmp files. Nonsense. nope. bmp is an entirely separate format. |
#139
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Is VLC 3.0.3 for Windows 7?
"NY" wrote
| | Knowing Apple they'd say "Go to the gas station and pull up at the pump with | a square (instead of cylindrical) nozzle on the holster" - because they like | to reinvent everything and do everything differently from everyone else. And it will cost you $49.95 for that new square fitting. | A case in point is how to copy photos that my wife took on her iPad. Nothing | as simple as plugging in a USB cable and seeing the iPad as a device in | Windows, as you would with Android or with a dedicated camera. Oh no. Awhile back I was trying to help a friend look into tablets. I knew almost nothing, as I've never used a tablet. I was trying to figure out what kind of functionality was available. At the Apple church I asked the clerk if iPads provided some kind of file system to store and access files. He had no idea what I was talking about. After conferring with other clerks he eventually came back and said that, yes, there's an app for that. It's called "Explorer". |
#140
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Is VLC 3.0.3 for Windows 7?
In article , Mayayana
wrote: Awhile back I was trying to help a friend look into tablets. I knew almost nothing, as I've never used a tablet. clearly still the case. I was trying to figure out what kind of functionality was available. At the Apple church I asked the clerk if iPads provided some kind of file system to store and access files. He had no idea what I was talking about. After conferring with other clerks he eventually came back and said that, yes, there's an app for that. It's called "Explorer". he's wrong. |
#141
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Is VLC 3.0.3 for Windows 7?
Mayayana wrote:
"NY" wrote | | Knowing Apple they'd say "Go to the gas station and pull up at the pump with | a square (instead of cylindrical) nozzle on the holster" - because they like | to reinvent everything and do everything differently from everyone else. And it will cost you $49.95 for that new square fitting. | A case in point is how to copy photos that my wife took on her iPad. Nothing | as simple as plugging in a USB cable and seeing the iPad as a device in | Windows, as you would with Android or with a dedicated camera. Oh no. Awhile back I was trying to help a friend look into tablets. I knew almost nothing, as I've never used a tablet. I was trying to figure out what kind of functionality was available. At the Apple church I asked the clerk if iPads provided some kind of file system to store and access files. He had no idea what I was talking about. After conferring with other clerks he eventually came back and said that, yes, there's an app for that. It's called "Explorer". Some things are just hard to do. 2017/06/05 https://techcrunch.com/2017/06/05/io...ystem-to-ipad/ "The company is also launching a new app called Files, which brings desktop-style file management to iPad" The presenter has been dwarfed by the concept. I didn't realize iPads were that big. What if that falls on you ? Is there a VESA mount ? https://beta.techcrunch.com/wp-conte...0917.jpg?w=680 Paul |
#142
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Is VLC 3.0.3 for Windows 7?
"Paul" wrote
| | And that's also related to BitBLT. Back in the day, | a system would have BITBLT as a form of graphics | acceleration. And it worked on bitmaps. | | https://en.wikipedia.org/wiki/Bit_blit | | That predates lots of other graphics acceleration | technologies. The article says BITBLT came from | Xerox PARC. | Acceleration? BitBlt usually stands for bit block transfer. It's also the name of the Windows function to copy a bitmap when it's done between "device contexts", as opposed to copying a byte array. | There was a short era of B&W graphics in there, | which really nobody got to see. The monitor may have | been monochrome (capable of gray scale), but the | frame buffers only had "1 bit pixels". Just black | and white as choices. | Those are still around. ICO files are composed of two bitmaps, or rather any number of pairs of bitmaps. Each image bitmap is paired with a mask bitmap. The mask bitmap is just black/white, to indicate which image pixels shouldn't be displayed, thus allowing for an image with transparent areas so that it didn't have to be rectangular. |
#143
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Is VLC 3.0.3 for Windows 7?
Mayayana wrote:
"Paul" wrote | | And that's also related to BitBLT. Back in the day, | a system would have BITBLT as a form of graphics | acceleration. And it worked on bitmaps. | | https://en.wikipedia.org/wiki/Bit_blit | | That predates lots of other graphics acceleration | technologies. The article says BITBLT came from | Xerox PARC. | Acceleration? BitBlt usually stands for bit block transfer. It's also the name of the Windows function to copy a bitmap when it's done between "device contexts", as opposed to copying a byte array. Ours would have been similar to this. https://research.swtch.com/bitblt "Bitblt combined a rectangle of a source image with a similarly-sized rectangle in a destination image using a boolean function and replaced the destination rectangle with the boolean result." With a boolean function being XOR perhaps. I think there was actually a table of functions printed on the card surface, for easy reference. (You would expect AND, OR, XOR, perhaps a NOT somethingorother thrown in, and the table would have all the opcodes shown for it.) It was unclear how the data was moved around, because there wasn't enough logic for a DMA circuit and sequencer. I would have been more interested, if there was a software library so I could play with it. Paul |
#144
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Is VLC 3.0.3 for Windows 7?
In message , Wolf K
writes: On 2018-08-14 17:26, nospam wrote: In article , J. P. Gilliver (John) wrote: Well, he was just dim, if he didn't realise that a JPEG_is_ a bitmap. it isn't. jpeg is a compressed file format True. which has nothing whatsoever to do with bmp files. Nonsense. Indeed. A JPEG is a compressed bytemap/bitmap. A BMP is an uncompressed one. -- J. P. Gilliver. UMRA: 1960/1985 MB++G()AL-IS-Ch++(p)Ar@T+H+Sh0!:`)DNAf I'm the oldest woman on primetime not baking cakes. - Anne Robinson, RT 2015/8/15-21 |
#145
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film vs CMOS
"nospam" wrote in message
... This means that if you take a photo on 120 film and on 35 mm, with appropriate focal lengths of the two lenses to give the same field of view of the subject in both cases, and use the same aperture, the DOF will be less on the 120 photo than the 35 mm photo. nope. it will be identical for the same image quality. So as long as film grain isn't the limiting issue, you should be able to take a photo on 120 film with a lens that gives a certain field of view, and then on 35 mm with a different lens that gives the same field of view, and if you use the same aperture on both lenses, you shouldn't see a shallower DOF on a print from the larger format negative? That goes against everything I've ever learned about photography, and the fringe benefit of using larger film (the main one being finer level of detail for the same type of film). I'll have to try taking comparison photos on my SLR and compact cameras, to test it. As I thought, the SLR photo has a shallower DOF than the compact, for same aperture and comparable lens focal lengths to give same field of view in both photos. Nikon D90, 18-200 mm lens, set to 150 mm, 35 mm equivalent=225mm, f5.6, image size 4288 x 2848 pixels https://s22.postimg.cc/phiylnsnl/DSC_0151.jpg Canon Powershot SX260HS, 4.5-90 mm lens, set to 34 mm, no 35 mm equivalent stated, f5.6, image size 4000 x 2664 https://s22.postimg.cc/k6420pe81/IMG_1316.jpg Both these are full frame, both focussed on the pins of the mains adaptor in the centre of the picture. Both pictures taken from same position (ie same distance to subject in foreground). Very similar image resolution. |
#146
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Is VLC 3.0.3 for Windows 7?
"J. P. Gilliver (John)" wrote:
In message , Wolf K writes: On 2018-08-14 17:26, nospam wrote: In article , J. P. Gilliver (John) wrote: Well, he was just dim, if he didn't realise that a JPEG_is_ a bitmap. it isn't. jpeg is a compressed file format True. which has nothing whatsoever to do with bmp files. Nonsense. Indeed. A JPEG is a compressed bytemap/bitmap. A BMP is an uncompressed one. Can you please stop making sense when nospam is carefully misinterpreting/ misrepresenting other posters!? Straw men are people too! |
#147
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Is VLC 3.0.3 for Windows 7?
"Frank Slootweg" wrote
| Can you please stop making sense when nospam is carefully | misinterpreting/ misrepresenting other posters!? Straw men are people | too! Ah. The refreshing voice of sanity. |
#148
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Is VLC 3.0.3 for Windows 7?
In article , Wolf K
wrote: Well, he was just dim, if he didn't realise that a JPEG_is_ a bitmap. it isn't. jpeg is a compressed file format True. yep. which has nothing whatsoever to do with bmp files. Nonsense. nope. bmp is an entirely separate format. JPG are compressed bitmaps. "Bitmap" has a wider reference than *.bmp files. https://en.wikipedia.org/wiki/Bitmap ...Similarly, most other image file formats, such as JPEG, TIFF, PNG, and GIF, also store bitmap images (as opposed to vector graphics), but they are not usually referred to as bitmaps, since they use compressed formats internally. in other words, what you're saying is technically true, but few people would make that claim. zip files are compressed files and folders. are you going to claim that there is no difference between the two? |
#149
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Is VLC 3.0.3 for Windows 7?
In article , J. P. Gilliver (John)
wrote: Well, he was just dim, if he didn't realise that a JPEG_is_ a bitmap. it isn't. jpeg is a compressed file format True. which has nothing whatsoever to do with bmp files. Nonsense. Indeed. A JPEG is a compressed bytemap/bitmap. A BMP is an uncompressed one. which means they're *different* formats, exactly as i said. an app that supports one format does not necessarily support the other format. or are you now going to claim that any app that can read a jpeg can also read a bmp? |
#150
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film vs CMOS
In article , NY
wrote: This means that if you take a photo on 120 film and on 35 mm, with appropriate focal lengths of the two lenses to give the same field of view of the subject in both cases, and use the same aperture, the DOF will be less on the 120 photo than the 35 mm photo. nope. it will be identical for the same image quality. So as long as film grain isn't the limiting issue, you should be able to take a photo on 120 film with a lens that gives a certain field of view, and then on 35 mm with a different lens that gives the same field of view, and if you use the same aperture on both lenses, you shouldn't see a shallower DOF on a print from the larger format negative? if you do that, then the image quality will be different, which means other characteristics may also be different. also, depth of field is a function of the physical aperture (not f/stop), so if you use the same f/stop on both (for exposure purposes) you're actually using a larger aperture on the longer focal length lens, thus the difference you're seeing (along with the difference in image quality from the larger format, which can't be ignored). That goes against everything I've ever learned about photography, it's a common myth. and the fringe benefit of using larger film (the main one being finer level of detail for the same type of film). in other words, different image quality. this explains it exceptionally well: http://www.clarkvision.com/articles/dof_myth/ A commonly cited advantage of smaller digital cameras is their greater depth-of-field. This is incorrect. € The myth, simply stated, is: smaller digital cameras have a larger depth-of-field than larger digital cameras. The simple reason why the myth is incorrect is that depth of field is set by aperture, focal length, and a criterion for spatial resolution, and if one keeps aperture of the larger camera the same as that in the smaller camera, the two cameras record the same image with the same signal-to-noise ratio and the same depth of field with the same exposure time. Below are details explaining why this is true, and Figure 1 gives an example. .... Given the identical photon noise, exposure time, enlargement size, and number of pixels giving the same spatial resolution (i.e. the same total image quality), digital cameras with different sized sensors will produce images with identical depths-of-field. (This assumes similar relative performance in the camera's electronics, blur filters, and lenses.) The larger format camera will use a higher f/ratio and an ISO equal to the ratio of the sensor sizes to achieve that equality. If the scene is static enough that a longer exposure time can be used, then the larger format camera will produce the same depth-of-field images as the smaller format camera, but will collect more photons and produce higher signal-to-noise images. Another way to look at the problem, is the larger format camera could use an even smaller aperture and a longer exposure to achieve a similar signal-to-noise ratio image with greater depth of field than a smaller format camera. Thus, the larger format camera has the advantage for producing equal or better images with equal or better depth-of-field as smaller format cameras. |
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