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View Full Version : How many megapixels = 35mm film?


Frankieplus
04-13-2006, 07:08 AM
What's the comparison in megapixels to film?

I'm looking at buying a 30D and want an indication of how sharp it is compared to a 35mm film camera.

Would 35mm film be 8.2 megapixels like the 30D is?

Next question is, how big can you blow up an 8.2 megapixel image before you start seeing grain? Like, what's an acceptable amount of blowing up? I'm just after an indication and a general idea.

I'm new to the digital world and any help with these questions would be appreciated.


-Frankie

Rob
04-13-2006, 07:26 AM
It's not really possible to compare them easily. Why? Well, film enlarged using traditional methods is a chemical process which yields very subtle results. It's easy to compare a negative scan, but this can vary technology wise from about 2MP to well over 50MP, depending on how closely resolved the scan was.

An 8MP camera can print a shot quite large, but what is acceptably large is entirely debateable. There is a load of crap talked on various websites about how big a 300dpi enlargement is going to be. The simple answer I would say is that a 20D compares very favourably with 35mm negative film when enlarged to sizes of easily A3. I've done this myself.

I am aware that plenty of people have printed A0 and other "poster" sizes with smaller MP cameras happily. I've also seen shots which are awful at web size.... The individual picture makes a big difference!

Rob

darich
04-13-2006, 07:52 AM
I've had 8.2mp images enlarged to 30x20 and 30x10 (both inches) and on close examination you can see grain but you don't look at a picture that size close up - you naturally want to back off a bit. When you do that they look great.
I've done the same enlargement using my 6.3 Digital Rebel before I sold it and those results were great too.

Feel free to buy a print from my site to see for yourself!!!

2framesbelowzero
04-13-2006, 08:13 AM
its the sensor-size which makes the difference. 20 mp is approaching something like a 35mm neg.

mentos_007
04-13-2006, 08:30 AM
It's not really possible to compare them easily. Why? Well, film enlarged using traditional methods is a chemical process which yields very subtle results. It's easy to compare a negative scan, but this can vary technology wise from about 2MP to well over 50MP, depending on how closely resolved the scan was.

An 8MP camera can print a shot quite large, but what is acceptably large is entirely debateable. There is a load of crap talked on various websites about how big a 300dpi enlargement is going to be. The simple answer I would say is that a 20D compares very favourably with 35mm negative film when enlarged to sizes of easily A3. I've done this myself.

I am aware that plenty of people have printed A0 and other "poster" sizes with smaller MP cameras happily. I've also seen shots which are awful at web size.... The individual picture makes a big difference!

Rob

Rob, I did a few A3 prints from my camera... 3MP and they are now exhibited. The quality is very good. I mean... I don't expect anyone to look at the photo from 5 cm distance... but it is framed on the wall and you won't notice artifacts from 50 cm.... So A3 is easily done here.... Actually from DSLR I expect something larger...

'Daniel'
04-13-2006, 08:33 AM
Feel free to buy a print from my site to see for yourself!!!

Nice.

darich
04-13-2006, 08:56 AM
Nice.

You gotta try these things, Daniel!!
Worst that can happen is no-one buys.....best thing is i get a few orders!!

:)

Rob
04-13-2006, 09:02 AM
Nice.

I was gonna say that actually... 10/10 for plugging your work Dave!

Rob

darich
04-13-2006, 09:26 AM
I was gonna say that actually... 10/10 for plugging your work Dave!

Rob
Cheers Rob!!
Still very few takers though..not through the site anyway. i have sold my California street shot 3 times though. Even another photographer appreciated it!!

DocFrankenstein
04-13-2006, 06:29 PM
I think it 20/30D approaches a properly developed ISO 400 film. Maybe ISO 200

But the difference is mostly practical. Do you want to shoot film or digital? What is the best medium for the job? How are you going to print film? What's the output?

Soocom1
04-13-2006, 06:35 PM
Ok…..

First you have to keep in mind that the film in comparison to digital debate is a bit miss leading. 35mm film cannot be directly compared to digital in the usual ‘size matters’ account.

Depending on the grain size (ala. ISO speed) the comparable Mp count can range from 18-24 Mp for 400 speed film to what I have read (and there is some debate on this) to as high a 75 Mp for 25 speed film or slower. The problem is that the Mp count also derives on sensor sensitivity, actual vs. usable pixels, etc. If using some Tech pan, I heard of a comparable Mp count of over 100 Mp, (but that was debatable.)

Next you have to consider the ability of the sensor to reproduce the actual image. Regardless of the Mp count, the question comes into how well does the sensor reproduce the image. When the first DSLRs came out in the early 1990’s, (Nikon DCS) the images were only 1-1.5 Mp. Do a search on the internet on pics taken with this beast, and you will see what I mean. All the megapixles in the world wont help if the camera is lousy, but in a small Mp camera like the Nikon DCS, the images were great for what it was.

In addition, the other question is the print media. I don’t care if you have 2 speed ISO Pan, if you print the image on lousy paper, through a lousy enlarger, shot through a lousy camera, forget it. Your out of luck on image quality.

Remember silver Halide paper has microscopic grains of silver.

Ink jet printers shoot tiny dots of ink that spread. The silver halide paper will be MUCH finer than the ink jet.

Now, the same hold true for file sizes. If you set the camera up the right way, and save the image the right way, you can go as large as a road sign billboard and not see much grain. But remember that at that size, (and viewing an image up close is tuff for something large like a 20x30) the image grain will probably not be noticed.

For the 30D don’t worry, be happy, and shoot away and have fun making planet sized images.

In time you can afford a 20 Mp Med. format for the same price as a film MF is now. Then you are really talking.

thebeginning
04-13-2006, 11:44 PM
i recently did a presentation on the myths and details of film vs. digital (35mm slide vs. 35mm or smaller digital sensors). In my opinion the ISO has littler to do with resolution that people think. For instance, I get the same detail (except much cleaner) with my 20d at ISO 400 than I can get with slide film at ISO 400 or 200 even. The issue is not just about megapixels. In past years, many film shooters complained that it would take a 30 or 40 megapixel camera to rival the resolution of 35mm film. However, over the past decade or so modern technology has progressed quite a bit and there are now several digital cameras that can consistently near, match, or exceed the pure resolution of 35mm film, even at low ISOs (for instance, nikon's d2x, canon's 5d and 1dsMKII).

One time I took some shots with my 20d at ISO 100 and immediately after took some shots with my 1n with the same lens using velvia (iso 50). The detail is cleaner in my 20d's images, and I actually prefer it's image quality. At this point, the resolution of 35mm isnt that much greater than popular 1.5/1.6 crop digital sensors, and there isnt a big enough difference to make resolution a deciding factor. The only thing that would make me want to shoot slides over digital is the larger color tone gamut.

You have to keep in mind that there is more to this issue than resolution, or else we'd all shoot 4x5. I think we can agree that image quality (and of course workflow and such, but I wont go into that) is the main 'subsection' on the debate. IMO, this is composed into 5 subcategories - resolution, color accuracy, color gamut, shadow/highlight capabilities, and grain/noise.

While film may have a slight edge on resolution (depends on the scanner used and the digital camera it is compared to), there are many other factors that go into what we view as a good photograph. As far as color accuracy, digital almost always takes the lead as the initial capture of digital is much more versatile than film. For instance, if you were shooting some landscapes in velvia in austria or something and saw some people that you wanted to take candids of, you might worry about using velvia because it botches skin tones terribly. This is partly a workflow or convenience issue, but it is still apparent that digital's capture is more versatile and accurate for color, even though there are types of slide film with good color accuracy. This is one reason why many portraiture photographers havent hesitated about switching to digital.

Color gamut and tonality goes to film. plain and simple. Even with 16-bit Tiff files in AdobeRGB or ProRGB and 32-bit HDR files, the color range (tonality ranges can equal or exceed slides in some situations) is almost always larger with slide film than with digital.

the shadow/highlight thing is basically split. Digital can capture more shadow details than slide film can, while film's highlight capacity is higher than digital's, and can capture subtle highlights that digital would just blow out. Neither is really bad at one or the other, just each has strengths and weaknesses.

Aside from possible color accuracy, one section of the debate that digital clearly wins is grain/noise. Digital is much cleaner than film. A digital sensor captures no grain at all (because the formation of the granular specs of film is a chemical process), but does have digital noise, which is slightly different. A digital camera (esp. that 30d, which has terrific noise capabilities) can capture cleaner images at ISO 400 than slide film can at ISO 100 (or even 50, depending on the film). However, in film's defense, the noise from digital sensors can be slightly more bothersome than film's grain because while grain retains a more gaussian spread, noise is more like tiny speckled splotches of color (which is only really noticeable at ISO 800 or 1600 and above).

Just keep in mind that it's not all about megapixels (resolution) nor sensor size as someone else mentioned (hence the d2x's capabilities). After all the research and comparisons I made while studying this topic, it has become apparent that when buying a dSLR such as the 20d, 30d, 350d, d70, d200, etc., you dont really need to worry about resolution. If the resolution of these cameras isnt good enough for you, chances are 35mm slides will dissapoint you also.

I'd say go buy that 30d, you'll love it. i've printed some large images from my 20d (16x24") and they turned out beautifully. I've come to a point where when printing orders for clients, no matter what sizes they order, I never have to worry about if my camera's resolution can cope. And that's what is important.

Alpha
04-14-2006, 12:52 AM
A digital camera (esp. that 30d, which has terrific noise capabilities) can capture cleaner images at ISO 400 than slide film can at ISO 100 (or even 50, depending on the film). However, in film's defense, the noise from digital sensors can be slightly more bothersome than film's grain because while grain retains a more gaussian spread, noise is more like tiny speckled splotches of color (which is only really noticeable at ISO 800 or 1600 and above).


There's no way that a camera like the 30D can touch low ISO slide film in terms of quality, even in 35mm. With the proper scanning equipment, something like a low iso Provia slide kills anything coming from a standard consumer dslr. Show me a 150mb, 5000dpi grainless photo from a camera with a sensor of equivalent size and i'll believe it. The very high MP digital cameras and backs do, indeed, compete with the quality of 35mm. But most, including the 30D, do not.

hammy
04-14-2006, 04:47 PM
Can't really compare scanned negatives to a real photographic print. Unless you've got a really high end scanner ($$$), it's not really a fair comparison IMO.

Alpha
04-14-2006, 05:30 PM
true...different scanning technologies yield different results as well. Flatbeds can be good, but I use my Super CoolScan 9000 whenever possible. However, even the highest setting (4000dpi, 16-pass, single laser) doesn't compare to a drum scanner. mmmm...drum scanners... :hail: BTW, why can't they make other things with that model name. I wish that I could drive a Super CoolMobile 9000, or maybe get myself something to eat out of my Super CoolFridge 9000. That would be sweet.

usayit
04-14-2006, 07:19 PM
The finest paintings in the world were painted with both fine and broad brushes....

hammy
04-15-2006, 02:50 AM
I wish that I could drive a Super CoolMobile 9000, or maybe get myself something to eat out of my Super CoolFridge 9000. That would be sweet.

:lol:

ksmattfish
04-15-2006, 07:34 AM
What's the comparison in megapixels to film?

Kodak says there is 50mp of info in a 35mm frame, but a print from 35mm film compares to a print from a 16mp DSLR.

It's always been more complicated than straight resolution comparisons anyway, and not all megapixels are created equal.

I'm looking at buying a 30D and want an indication of how sharp it is compared to a 35mm film camera. Would 35mm film be 8.2 megapixels like the 30D is? Next question is, how big can you blow up an 8.2 megapixel image before you start seeing grain? Like, what's an acceptable amount of blowing up? I'm just after an indication and a general idea.

I bought a 20D a year ago, and I have to say as a hardcore film geek for the last 12 years, I was stunned. I do think 35mm still has the edge in resolution over an 8mp x1.6 size sensor, but that difference disappears if you are shooting hand held, with zooms, etc... I don't like to enlarge ISO 400 35mm beyond 8"x12", but I think my 20D ISO 400 shots look good at 12"x18".

One issue is that diffraction caused by small apertures is a bigger issue with a smaller size sensor. http://www.cambridgeincolour.com/tutorials/diffraction-photography.htm

Get a 30D, you'll love it. Don't expect immediate perfection. It's a new tool, and it requires practice and experience. I do most of my own BW film processing and printing, but I was dropping color film off at the lab. Going from RAW file to color print takes new skills, but I'm enjoying color photography more than I ever have.

Keep using your film gear too! I think it's probably a fact that digital will surpass film in most technically measured ways in the next 5 years, 10 years at the most. That just means that there will be a lot of high resolution, HDR crap photography out there. ;)

Frankieplus
04-15-2006, 07:47 AM
I feel like too much of a niewbie asking this but hey..

Love the shots on your blog, Matt. How do you get that wide frame? I don't mean the wide angle lens you're using but the wide 'thin' frame that most of your shots have?

Is it the camera, the film?

Or is it basically a 'normal' shot that's been cropped that way?


-Frankie

ksmattfish
04-15-2006, 12:09 PM
How do you get that wide frame? I don't mean the wide angle lens you're using but the wide 'thin' frame that most of your shots have?

You mean the thin black line? Some of that frame that shows on the main blog page is part of the blog template. The thin black line that you can see when you click on a pic is made in one of two ways.

If the scan is from a print, the thin black line is because I use a homemade neg carrier in my enlarger that is actually slightly larger than the neg. The line is from printing the clear film area around the edges of the neg frame.

If the scan is from a neg, the thin black line is created by increasing canvas size slightly with a black background in Adobe PS. I'm trying to make my neg scans look like the prints. Almost all my Widelux files are from neg scans, because the prints are usually too big for my scanner.

If you mean the panoramic format of the image, just yahoo "swing lens panoramic camera", or check out those links on my photoblog for Widelux specific info.

thebeginning
04-15-2006, 04:09 PM
There's no way that a camera like the 30D can touch low ISO slide film in terms of quality, even in 35mm. With the proper scanning equipment, something like a low iso Provia slide kills anything coming from a standard consumer dslr. Show me a 150mb, 5000dpi grainless photo from a camera with a sensor of equivalent size and i'll believe it. The very high MP digital cameras and backs do, indeed, compete with the quality of 35mm. But most, including the 30D, do not.


oh I beg to differ, although like you said, it matters heavily on the equipment used (scanner, etc.). I do not do my own scanning, but take my slides to a pro lab where they do ultra high resolution drum scans before lowering the dpi to 500 (my own request) for output. But that is not what I was even talking about. Most of what you just said concerned resolution (high MP digital camera/back, etc.), which is not at all the issue here. The issue is grain/noise. If I could see grain in a scan of lower resolution, wouldnt that show all the more that the slides had significant grain? Also, I noticed grain in them even when I first looked through them on a light table. That is with iso 50 velvia and iso 100 provia. With my 20d, i actually have to manipulate my ISO 100 images quite a bit just to see noise at all.

Also, that whole 5000dpi is largely misleading. I'd like to see a print from a 500dpi that is noticeably worse than a 5000dpi print. nobody prints that high.

ksmattfish
04-15-2006, 06:32 PM
Also, that whole 5000dpi is largely misleading. I'd like to see a print from a 500dpi that is noticeably worse than a 5000dpi print. nobody prints that high.

Who prints 500 dpi? All the pro labs I use print at around 300 dpi max.

thebeginning
04-15-2006, 11:36 PM
usually that's the case (300dpi). a couple of places that i've been to have recommended more (say 500dpi), but it doesnt really matter. I do 300 usually for my digital prints because if it's higher the printing co. will lower it to 300 i think anyway. I have my slides at slightly higher dpi just to capture that least little bit past 300dpi.

THORHAMMER
04-16-2006, 01:06 AM
the real awnser is a 35mm sensor will match film the best. Currently none are that large. mp doesnt really mean much without knowing the sensor size, a alot of point and shoot 6 mp cameras have tiny sensors and there is a lot of interpolation....

thebeginning
04-16-2006, 01:52 PM
the real awnser is a 35mm sensor will match film the best. Currently none are that large. mp doesnt really mean much without knowing the sensor size, a alot of point and shoot 6 mp cameras have tiny sensors and there is a lot of interpolation....

good point about the megapixels. i think you might be mistaken about the sensor sizes though, as there are 3 cameras out now that have full frame 35mm sensors (canon 1ds (i believe), canon 1dsMkII, and canon 5d). Not to mention medium format digital backs which have sensors even larger.

selmerdave
04-16-2006, 02:39 PM
Also, I noticed grain in them even when I first looked through them on a light table. That is with iso 50 velvia and iso 100 provia.

Considering it's nearly impossible to discern any grain whatsoever in a print that might be 100 times the size of the slide (9" x 14"?), you're basically claiming to have better than 100 times the vision of most 20/20 people.

Dave

thebeginning
04-16-2006, 03:52 PM
i used magnifiers.

THORHAMMER
04-17-2006, 02:43 AM
hey, i was reading the wrong info... you are totally right. I didnt realize they were actualy 24x36mm until i just looked it up... I guess that means I need to upgrade from my 300D pretty soon lol!!!!!!!!!!!!!!!

Alpha
04-17-2006, 01:43 PM
There is absolutely no way you could possibly see any grain looking at a Velvia 50 slide on a lightboard. I have a very difficult time finding grain with that film when I super zoom in on a 3000dpi scan.

Rob
04-17-2006, 02:02 PM
There is absolutely no way you could possibly see any grain looking at a Velvia 50 slide on a lightboard. I have a very difficult time finding grain with that film when I super zoom in on a 3000dpi scan.

I dunno - I've mis-exposed velvia to the point of the film breaking down and going wierd - you could see the grainyness in a 35mm negative :lol:. I've not had any luck with slide film, particularly Velvia... I now hate it on principal!! But I'm wierd like that.

Jeff Canes
04-17-2006, 03:55 PM
I have 2MF, a dozen 35mm and 8 & 6 mp DSLR cameras. IMO my 6mp 10Dl is already better that 35mm film.

2framesbelowzero
04-17-2006, 04:08 PM
the real awnser is a 35mm sensor will match film the best. Currently none are that large.


hi ThorHammer - there is one now with a 35mm sensor , but i forget who is making it...check dpreview