 |
 | Home | Contact Us | FAQ | Search & Site Map | Link to Us |
 | Sign In | Join | Other 45 Sites in Network |
| PhotoKB HomeDiscussion Groups Digital Photography Digital PhotoDSLR CamerasZLR CamerasPoint & Shoot CamerasFilm Photography 35 mmLarge FormatMedium formatDarkroomFilm and LabsOther EquipmentPhoto Technique Nature PhotographyPeople PhotographyTechnique GeneralGeneral Photo Topics General TopicsAustralian PhotographyUK PhotographyDirectoryPhoto Clubs |
Photo Forum / General Photo Topics / UK Photography / February 2005How many pixels..?
Just been looking at the Canon D 20. Whilst it is a very nice camera, and certainly pretty hot at 8.2MP, irt made me think of a question. I guess the makers are chasing the Holy Grail of so many pixels that even the most critical film advocate can tell the difference at large blow-ups. So, and I assume that as camera sensors get more pixels the pixels get smaller, how many pixels is equivalent to a good film photograph? What number of pixels IS the Holy Grail? Or has the question no answer? David > Just been looking at the Canon D 20. Whilst it is a very nice camera, and > certainly pretty hot at 8.2MP, irt made me think of a question. I guess the [quoted text clipped - 3 lines] > many pixels is equivalent to a good film photograph? What number of pixels > IS the Holy Grail? Well, as a *rough* guide, approximately 15-20,000,000 pixels is taken as being akin to Kodak/Fuji 100 ISO negative film. Kodachrome is estimated at about 50-60,000,000 pixels. But you really, really don't need 20,000,000 pixels to produce prints that would confuse just about anyone as to their origins. I have prints on my wall, 18"x12", shot on a 2.89Mp Nikon D1H and I'd defy you to notice unless you were told.  SignatureNeil Barker Tahnks neil. David >> Just been looking at the Canon D 20. Whilst it is a very nice camera, and >> certainly pretty hot at 8.2MP, irt made me think of a question. I guess [quoted text clipped - 16 lines] > on my wall, 18"x12", shot on a 2.89Mp Nikon D1H and I'd defy you to > notice unless you were told. > Tahnks neil. > [quoted text clipped - 21 lines] >> on my wall, 18"x12", shot on a 2.89Mp Nikon D1H and I'd defy you to >> notice unless you were told. I think Neil is being a bit complimentary to film here. I am no expert, but I have looked into this in depth. Professional consensus seems to be around 5 or 6 Mega pixels for 35mm (though they blow up with better resolution than my scans of large prints from 35mm). A recent large article in a magazine (sorry can't remember) which reckoned that the latest Canon with just over 11 Mega pixels makes medium format cameras obsolescent. Dave W. > I think Neil is being a bit complimentary to film here. Ummmm. Film. Hate the stuff. > I am no expert, but I have looked into this in depth. Professional > consensus seems to be around 5 or 6 Mega pixels for 35mm Rhubarb !!!! > (though they blow up with better resolution than > my scans of large prints from 35mm). A recent large article in a magazine > (sorry can't remember) which reckoned that the latest Canon with just over > 11 Mega pixels makes medium format cameras obsolescent. Excuse me while I climb back onto my chair, after falling off it laughing.... I'd love to see this 'article', I really would. SignatureNeil Barker >> I think Neil is being a bit complimentary to film here. > [quoted text clipped - 15 lines] > > I'd love to see this 'article', I really would. Its most likely in Practical Photography the page after the Canon add > "Neil Barker" <neil@nemesis.nu> wrote in message >> >>> I am no expert, but I have looked into this in depth. Professional >>> consensus seems to be around 5 or 6 Mega pixels for 35mm >> >> Rhubarb !!!! This would depend on the quality of the 35mm film, and the quality of the developing. A 6 Megapixel camera would be far better than a poor quality 35mm film. >> "Neil Barker" <neil@nemesis.nu> wrote in message >>> [quoted text clipped - 5 lines] >This would depend on the quality of the 35mm film, and the quality of the >developing. And the quality of the megapixels. Frink SignatureDoctor J. Frink : 'Rampant Ribald Ringtail' See his mind here : http://www.cmp.liv.ac.uk/frink/ Annoy his mind here : pjf at cmp dot liv dot ack dot ook "No sir, I didn't like it!" - Mr Horse > >> "Neil Barker" <neil@nemesis.nu> wrote in message > >>> [quoted text clipped - 7 lines] > > And the quality of the megapixels. Very much so. Too many people get caught up in an obsession for megapixels - sheer numbers don't always equal good quality. SignatureNeil Barker > > "Neil Barker" <neil@nemesis.nu> wrote in message > >> [quoted text clipped - 6 lines] > developing. A 6 Megapixel camera would be far better than a poor quality > 35mm film. Hence why I specified Kodak/Fuji. SignatureNeil Barker > >> A recent large article in a magazine (sorry can't remember) which > >> reckoned that the latest Canon with just over [quoted text clipped - 4 lines] > > > > I'd love to see this 'article', I really would. > Its most likely in Practical Photography the page after the Canon add LOL ! Now what *are* you trying to suggest.... SignatureNeil Barker >> I think Neil is being a bit complimentary to film here. > [quoted text clipped - 4 lines] > > Rhubarb !!!! You really need to check your research. There's no definitive answer to a question like this... it amazes me how many times questions like this come up and the same arguments run backwards and forwards over and over again! Ahh well, I've had a pretty boring day, I might as well join in. I'd like to know what *rough* estimate gives 15-20,000,000 pixels on film and 50-60,000,000 pixels on Kodachrome. How did you acheive these results Neil? What format film are you talking about? Can I assume 35mm? Let's take Fuji Velvia. It's a good slide film and produces quite high definition. Most of the resources I've found suggest it can resolve somewhere 60 and 160 lines/mm. This is very, very easy to find out on the web and Fuji publish this data. Actually, it took me only a couple of minutes to find this from Fuji: http://home.fujifilm.com/products/datasheet/pdf/AF3-960E.pdf Check section 17 - resolving power. According to them, low contrast targets give 80 lines/mm, high contrast is 160 lines/mm. OK. So a 35mm frame is 36mm x 24mm. At 80lpmm, using a relatively simple calculation, thats 36 x 80 x 24 x 80 = 5,529,600 Oh dear. That's not exactly 15-20 megapixels is it? Let's try 160lpmm: 36 x 160 x 24 x 160 = 22,118,400 pixels Yay! That's more like it! So. ISO 50 Velvia *might* deliver you somewhere between 5.5 - 22 megapixels, depending on the contrast of the target. Plus, you haven't even begun to factor in the resolving power of the lenses being used, the conditions of a shot, etc. If you are going to be acheiving anywhere *near* 20 million pixels, you'd better have one hell of a decent camera set up; high quality lenses at a wide aperture, a really sturdy tripod, off-camera metering and mirror lockup. Hand-held, you might be lucky to maintain 5 megapixels under any circumstances. However, I went down this road some time ago trying to find a definitive answer.. I eventually came up with my own: What the hell am I trying to do figuring out how many PIXELS I can get out of FILM?!?! Film is an analogue medium. If you want pixels, get a digital camera. There are far more important issues to base a decision on what camera gear you should be using than 'how many pixels has film got?' IMHO, if you are purely after the highest-quality print you can get, then you need a large format camera, the ability to use it properly and access to a darkroom or a lab than can handle that type of print. It will knock your socks off the amount of detail you can see in an 8x10. That said, some experiments claim that photographic paper can only resolve between 300-600DPI anyway. So there's another argument for you guys to talk about. Nice use of the word 'rhubarb', btw. :) Chris. >> (though they blow up with better resolution than >> my scans of large prints from 35mm). A recent large article in a magazine [quoted text clipped - 6 lines] > > I'd love to see this 'article', I really would. Chris B <lord_waymasterNO@SPAMyahoo.com> observed >Let's take Fuji Velvia. It's a good slide film and produces quite high >definition. Most of the resources I've found suggest it can resolve [quoted text clipped - 22 lines] > >Yay! That's more like it! Maybe, and sorry I have neither the time nor the skills to reply in detail, but there's a big fallacy there. lines per mm is something quite different from pixels. A black & white target in lines per mm represents a sinusoidal curve of light dark intensities at the limit of resolution. That's quite different from an on-off pixel. It requires *lots* of pixels to replicate a b&w target. Over to the experts..... Mike [The reply-to address is valid for 30 days from this posting] SignatureMichael J Davis <>< Some newsgroup contributors appear to have confused the meaning of "discussion" with "digression". <>< > A black & white target in lines per mm represents a sinusoidal curve of > light dark intensities at the limit of resolution. That's quite > different from an on-off pixel. It requires *lots* of pixels to > replicate a b&w target. This makes a great deal of sense... > You really need to check your research. Do I ? What research did I personally do ? > There's no definitive answer to a > question like this... it amazes me how many times questions like this come > up and the same arguments run backwards and forwards over and over again! Indeed. And here we are again. > Ahh well, I've had a pretty boring day, I might as well join in. > I'd like to know what *rough* estimate gives 15-20,000,000 pixels on film > and 50-60,000,000 pixels on Kodachrome. How did you acheive these results > Neil? What format film are you talking about? Can I assume 35mm? 35mm film was mentioned, so I'd have thought that would be taken as read. FYI, I recall reading this in a scientific paper a year or so ago. No, I can't name you the exact one, as I'd got other things to do than to make a record of it for future use. Do note that this paper was talking about theoretical examples of how many pixels film represents and not practical. It has also been mentioned that you cannot directly compare lines/mm to numbers of pixels, something I agree with. > However, I went down this road some time ago trying to find a definitive > answer.. I eventually came up with my own: What the hell am I trying to do > figuring out how many PIXELS I can get out of FILM?!?! Quite. It's one of those tedious subjects that in practise, simply doesn't matter :-) SignatureNeil Barker >> Tahnks neil. >> [quoted text clipped - 28 lines] >(sorry can't remember) which reckoned that the latest Canon with just over >11 Mega pixels makes medium format cameras obsolescent. You should have stopped after your second sentence, unless this is simply a troll. I have an archive of around 7,000 Kodachrome slides, and they require scanning at significantly more than 11 Mp to retain all the detail. Note that Hollywood is looking at around 12-15 Mp as an *adequate* substitute for film. Movie negatives are of course equivalent to half-frame 35mm stills, plus the perceived improvement in resolution for movies due to the eye averaging over several frames. SignatureStewart Pinkerton | Music is Art - Audio is Engineering > detail. Note that Hollywood is looking at around 12-15 Mp as an *adequate* > substitute for film. Movie negatives are of course equivalent to > half-frame 35mm stills, plus the perceived improvement in resolution for > movies due to the eye averaging over several frames. I worked for a computer special effects co. We would routinely scan film at around 4000x2000 and 6000x3000 (depending on the budget of the film) and also then shoot it back out to film with the digital effects at similar resolutions. >> detail. Note that Hollywood is looking at around 12-15 Mp as an >> *adequate* [quoted text clipped - 6 lines] > and also then shoot it back out to film with the digital effects at > similar resolutions. At last - someone who has actual experience! The theories are interesting but the practice is most useful. >>> detail. Note that Hollywood is looking at around 12-15 Mp as an >>> *adequate* [quoted text clipped - 10 lines] > >The theories are interesting but the practice is most useful. Yup, and if the budget allows, the preferred number is 18 megapixels for a half-frame image which isn't going to be subjected to still-frame scrutiny. 'Nuff said? SignatureStewart Pinkerton | Music is Art - Audio is Engineering I run a website which receives many unsolicited photorgraphs. Remarkably few senders of these seem to know how to resize their digital images to a reasonable 480 x 360 pixels and I can see how the average digital camera has gone from 1 to 4 megapixels by the size of the downloads. Personally I'd like to see al amateur camera limited to 1 megapixel but I suppose I'm just being grumpy! >Just been looking at the Canon D 20. Whilst it is a very nice camera, and >certainly pretty hot at 8.2MP, irt made me think of a question. I guess the [quoted text clipped - 7 lines] > >David > Just been looking at the Canon D 20. Whilst it is a very nice camera, and > certainly pretty hot at 8.2MP, irt made me think of a question. I guess the [quoted text clipped - 7 lines] > > David This article http://www.normankoren.com/Tutorials/MTF7.html seems to go into this in some detail. Quoting from the test: "a full-frame sensor with 8.3 megapixels would have resolution equal to 35mm film. Slightly more pixels would be required for smaller sensors with lenses designed to cover full-frame 35mm." anthony. > This article http://www.normankoren.com/Tutorials/MTF7.html seems to go into > this in some detail. [quoted text clipped - 4 lines] > film. Slightly more pixels would be required for smaller sensors with lenses > designed to cover full-frame 35mm." You can't generalise saying "35mm film" though - there's a hell of a lot of difference between Kodachrome 25 and Krapo-colour 800 ISO. SignatureNeil Barker >> This article http://www.normankoren.com/Tutorials/MTF7.html seems to go into >> this in some detail. [quoted text clipped - 7 lines] > You can't generalise saying "35mm film" though - there's a hell of a > lot of difference between Kodachrome 25 and Krapo-colour 800 ISO. Fuji Provia 100F film was used. anthony. |
Reply to this Message |
 Sign In
 Join
 My Latest Posts My Monitored Threads My Blog My Photo Gallery My Profile My Homepage Start New Thread Enable EMail Alerts Rate this Thread
|
©2008 Advenet LLC Privacy Policy - Terms of Use
This website includes both content owned or controlled by Advenet as well as content owned or controlled by third parties.