Epic is the Ultimate "Film Slayer".... IF

[Daniel Browning]

That's very interesting. I've never heard that argument before.

Thanks, I enjoy sharing useful information.

So you are saying that given two sensors that are the same size and that process images the same way the one with MORE pixels will have LESS noise?

Yes. The greatest density of photosites are the most efficient and the lowest density are the least efficient. By that I mean the signal to noise ratio.

Larger sensors do not have a proportionately less amount of noise than smaller sensors, relative to area, which is light gathering ability. In other words, a sensor that is 23 times larger does not have that much less noise. As size drops, efficiency (per unit of area) goes *up*. More on this below.

Everything I've experienced myself and have encountered in the work of others seems to work counter to your argument. You state that the 1DsMarkIII has the lowest noise of any DSLR, but isn't the Nikon D3 the current low noise king?

The D3 is the per-pixel low-noise king, but the 1Dsm3 is the per-image low-noise king, by a small margin. Only the latter title has any meaning.

It has half the photosites of the 1DsMarkIII and achieves lower noise with less severe noise reduction. I'm just pointing to one comparison here but there are far more on the net with the same conlcusions: http://luminous-landscape.com/essays/comparison.shtml

Your edit is correct, this is the kind of flawed comparison that I was talking about when I said "People think smaller photosites are worse because they make flawed comparisons, such as viewing 100% pixel size instead of correctly resampling to the same resolution with a sinc algorithm".

To illustrate, imagine a 200 MP camera, let's call it ACS (I love Hubble!). If we compared 100% crops from ACS and D3, and the ACS had three times more noise, this flawed comparison would indicate that the D3 is better. Now imagine resizing those 200 megapixels down to just 12. The reduction in noise would be far greater than just a magnitude of 3, and the D3 would appear to be much noisier.

Now change the illustration from ACS to 1Ds3 and 200 megapixels to 21. See how it reduces apparent noise?

The comparison is further flawed by using inequal exposures (1/40 vs. 1/50), not accounting for Nikon's black point clipping (not apparent in their image anyway) or especially their chroma desaturation.

In it Michael Reichman reiterates the point that I thought was common knowledge: "The 1D MKIII's sensor at 10MP is closer to the D3's 12MP than the 1Ds MKIII's 21MP, and the pixels of the Nikon are bigger, so theoretically of lower noise. The D3 is also closer in price to the 1D MKIII than to the 1Ds MKIII."

The D3 is an excellent camera. I think it has as much as a full stop less image noise than the 10 MP 1Dm3, quite an achievement.

I thought that sensors with larger and fewer photosites were inherently less noisy than ones that are more denseley packed with smaller photosites.

Again, true at the pixel level but not when viewing the image as a whole. Another illustration of the 100% comparison flaw: take a beautiful 12 MP image: the 100% crops look great and the 8x10 prints look great. Now resize it to 21 MP. Add just a little noise in photoshop, enough to be visible at 100%, but not enough to be visible in the 8x10 print. Print both at 8x10 and compare: they are identical. But at 100% crops, one looks worse than the other.

In real life, are you going to crop a 4x6 out of your 21 MP image? Or are you going to resize it to 4x6 for printing? (People do all sorts of things online that they wouldn't in real life.)

Isn't this why 12mp digicams are far noisier than 6mp digicams at high isos?

A common misconception. Resize the 12 MP down to 6 MP and it will look better. Especially if the 6 MP is an older model.

Isn't this why Pentax had to reengineer the way their sensors worked in order to achieve the same level of noise in their 14mp K20d as they had in the 10mp K10d.

Right. Engineers are increasing density and efficiency at the same time. The big sensors are still nowhere near the digicam efficiency, but they've been following Moore's Law so far, which means we have a lot to look forward to.

Does the D300 have lower noise then the D3 then?

No.

You claim that people aren't resizing and resampling images properly when doing these tests. So why not try to compare images from cameras with the same number of photosites but in different sized sensors.

Let's compare the Canon G9 with the Canon 5D. Both 12 megapixels. The G9 packs 12 megapixels in 37 square mm. The 5D spreads itself out over a luxurious 864 square mm. That means the 5D has the opportunity to capture 23 times more light (a function of area). But does it? And does it have 23 times less noise? No, because it is far less efficient than the digicam.

Imagine someone took the Canon 5D sensor and wanted to make a 1/1.7" digicam out of it. So they got an exacto knife out and cut the center 37 square mm out of the 5D sensor and put it in a little camera. On that area, the 5D had 0.5 megapixels. But they're *good* pixels. If you look at the 0.5 MP image at 100%, it's clean and nice, whereas the 12 MP G9 image at 100% looks very noisey. Now resize the 12 MP G9 down to 0.5 MP... the 5D crop looks terrible in comparison. If you don't have an exacto knife, you can do the same experiment by cropping the center 0.5 MP in photoshop out of the Canon 5D. Thus proving that sensors can have *more* pixels in the same area to capture more light and less noise.

If they made the 5D with the same pixels as the digicam, it would have 280 megapixels. And by the time you resize that back down to 12 MP to compare with the real-life 5D, it would have a lot less noise. Obviously, they would if they could. But it dispels the fear that more pixels will mean more noise.

I know for a fact that the images I get off my 6mp DSLR are far cleaner than those that I get off of my 6mp Canon Powershot. Would you attribute this to the dslr having heavier noise reduction? I always thought it was because the photosites in the dslr were larger and less densley packed therefore generating less heat.

I have the same experience with my Canon DSLR and digicams. In addition to the comparison flaws I have explained, I think there is another big reason why so many have the misconception about dense pixels: digicams stink. They have small sensors and terrible processing (no raw, or if they have it it's dog slow). Thank goodness RED got it right.

[Steve White]

Daniel Browning - your posts in this thread have been nothing short of wonderful. Thank you for clearing up the misconceptions about noise.

I think the legitimate fear of the smaller photosites has to do with clipping and dynamic range. For a given photosite, you can only bin so many photons before you've filled it. The total number of photons you can represent in your image is your dynamic range for that photosite. This argument is flawed too however, since what really limits you is the combination of how many photons you collect, how many photosites you have, and how many photons each photosite can hold (plus what the signal to noise of each photosite is).

Suppose for example, that you bring in 100 detectable photons with your lens and focus them onto a single photosite, that can hold 50 photons. In this case, you end up with clipping.

On the other hand, suppose you had 100 photons evenly focused into 4 smaller photosites that could collect 25 photons each, occupying the same area as your 50 photosite detector. In this system, you actually collect all 100 photons and have fully capured the image. While the dynamic range of each photosite is lower, the dynamic range of the image is higher.

Now the problem is in how you represent the data. It's easy to make mistakes of course, but if you sampled RAW, you're at a good starting point so that someone with better algorithms can get better results.

I know for a fact that the images I get off my 6mp DSLR are far cleaner than those that I get off of my 6mp Canon Powershot. Would you attribute this to the dslr having heavier noise reduction? I always thought it was because the photosites in the dslr were larger and less densley packed therefore generating less heat.

Keep in mind that the DSLR probably has a significantly larger lens than your digicam. Suppose they had the exact same sensor, but the DSLR had a 72 mm outside diameter lens, and the digicam had a 36 mm outside diameter lens. In this case, the 72 mm lens collects 4x as much light as the 36 mm lens. Thus, the sensor has 4x as much information to produce the image. This is of course, why telescopes have such large lenses - they need to collect a lot of light.

[Bing Bailey]

wasn't this an EPIC thread ?

[Steven Caesare]

Daniel Browning - your posts in this thread have been nothing short of wonderful. Thank you for clearing up the misconceptions about noise.

I think the legitimate fear of the smaller photosites has to do with clipping and dynamic range. For a given photosite, you can only bin so many photons before you've filled it. The total number of photons you can represent in your image is your dynamic range for that photosite. This argument is flawed too however, since what really limits you is the combination of how many photons you collect, how many photosites you have, and how many photons each photosite can hold (plus what the signal to noise of each photosite is).

Suppose for example, that you bring in 100 detectable photons with your lens and focus them onto a single photosite, that can hold 50 photons. In this case, you end up with clipping.

On the other hand, suppose you had 100 photons evenly focused into 4 smaller photosites that could collect 25 photons each, occupying the same area as your 50 photosite detector. In this system, you actually collect all 100 photons and have fully capured the image. While the dynamic range of each photosite is lower, the dynamic range of the image is higher.

Now the problem is in how you represent the data. It's easy to make mistakes of course, but if you sampled RAW, you're at a good starting point so that someone with better algorithms can get better results.


Keep in mind that the DSLR probably has a significantly larger lens than your digicam. Suppose they had the exact same sensor, but the DSLR had a 72 mm outside diameter lens, and the digicam had a 36 mm outside diameter lens. In this case, the 72 mm lens collects 4x as much light as the 36 mm lens. Thus, the sensor has 4x as much information to produce the image. This is of course, why telescopes have such large lenses - they need to collect a lot of light.

But your photon count per area ratio doesn't change. If the smaller photosite can only handle 50 photon, but you can fit twice as many sites in the same physical area, you still can handle detecting all ths photons.

Two five gallon buckets fit in my bath tub. I can pour 10 gallons of water in and hold it all. replace the buckets with ones that can only hold 2.5 gallons each. However, four of these smaller buckets fit in my bathtub. I can still pur 10 gallons of water...

[Zack Birlew]

Epic is going to be awesome, that much is clear. The more interesting question is how is the RED One going to upgrade its sensor and how much will that cost?

Once that gets into the picture, then things will really get interesting. Also, the accessories are obviously going to be different, otherwise, why would you buy the Epic if you can save *possibly* a few thousand by buying a RED One with an upgraded sensor? Perhaps there's something about Epic that hasn't been revealed yet?

Well, enough speculation. I agree, from what I've been reading about the RED One so far, the dynamic range has got to get better. Having 11 stops or whatever at a high ISO isn't very helpful if you can't even see the images through the garbled video gain. Another thing that could change the game is if RED actually does implement or allows for the IMS interchangeable lens system by default. Then the camera would truly be open to independent and pro filmmaker alike, because then you can use any lense with the RED cameras.

Workflow is another big issue. This year's NAB and REDUser party were very eye opening as far as the RED workflow goes. I thought my Mac Pro would have handled everything just fine, well, now I know that I would need a Kona card or equivalent, a production LCD, and a big RAID array in order to do the kinds of things I planned on doing with my RED. Even then, I would need at least a Macbook Pro in the field with me just so I could offload footage, not a big deal but it didn't hit me until then. Also, Scratch would almost be a neccessity. But, granted, you can get around a lot of this by working in 2K or lower resolution. However, I think the biggest problem right now is that there still isn't support for 4K 16:9. Obviously most of this can be solved with software support and bigger storage devices (ie. RED Flash, fast 32gb CF cards, etc.) but that's just the way it is at the moment and a big part of what needs to be overcome to become a true replacement to film.

[Zakaree Sandberg]

honestly.. I think Red One, is the "film killer" that we were all looking for (not literally, but maybe..) I would hate to see people off the bat shy away from using RED ONE because Epic is a bigger badder version. The New sensor will be a must have, wether you stick with red one and opt for the upgrade or go ahead and grab the epic. I believe Epic is designed for HIGH HIGH end work and will be amazing on the effects shots, but RED ONE will still be a work horse for most features, commercials, and tv shows (hopefully)
How much better can things get? i mean I had the HD laser eye surgery and i see 20/13 and yet i thought superbad (shot on genesis) looked good. I havent seen RED stuff Printed to film and projected yet, But i cant wait.

[Steve White]

But your photon count per area ratio doesn't change.

That is not a fact, that is an assumption. If you were designing photosites, you would want to increase this ratio, lower the area, and decrease the noise floor.

[Tom Lowe]

Zakaree, I never thought Red One would be the "nail the in coffin" for film. I have always speculated (openly here and at cinematography.com, etc) that Red's second offering would be the beast to slay chemical film for motion pictures. Epic seems tailored made for this role, if only the DR can be brought closer to film. But as some have pointed out, even high-end DSLRs have not completely matched film's DR, but that did not stop them from putting film still cameras out to pasture. (I realize that some photogs do continue to shoot chemical film stills, but they are few and far between these days.)

Daniel Browning, thanks for your posts. I think I actually learned something here today! What you seem to be saying is that a Canon 350D (which I shoot on) will have less visible noise than a 450D, when viewed pixel for pixel, but once you downsample the 450D's image to 8MP, it will appear cleaner than the 350D. So, for example, if your end goal was a 1920x1080 pixel frame, the 450D downsampled to 1920x1080 would show less noise than the 350D downsampled to 1920x1080.

[Daniel Browning]

Daniel Browning, thanks for your posts. I think I actually learned something here today! What you seem to be saying is that a Canon 350D (which I shoot on) will have less visible noise than a 450D, when viewed pixel for pixel, but once you downsample the 450D's image to 8MP, it will appear cleaner than the 350D. So, for example, if your end goal was a 1920x1080 pixel frame, the 450D downsampled to 1920x1080 would show less noise than the 350D downsampled to 1920x1080.

You're welcome. Yes, that's what I'm saying. The 450D is no slouch when it comes to per-pixel noise, either, but I think the 350D still beats it by a small margin. (I haven't got a 450D yet, I'm waiting for the 1000D ;-).)

Your remark about downsampling to 1920x1080 highlights an important difference between stills and digital cinema. With still photography, you can choose between getting less noise by printing smaller (8x10), or getting more resolution by printing larger (30x20).

That choice doesn't exist in cinema. When I first saw a top-notch 2K digital projection, the difference from film projection was so striking that I vowed to never go back to a regular 35mm theater again. Unfortunately, 2K digital projection is rare and 4K is rarer still. Sure, filmouts are ubiquitous, and the whitepapers cite nearly 1.4K, but my eyes tell me the comparison is even more disparate. Anyway, 1080p, 720, DVD9, and web distribution will all benefit from the resize. Remember the ISO 12,000 stills that Jim posted?

By the way, Tom, I really enjoyed your Joshua Tree astrophoto timelapse. Last time I was there I had telescopes but no cameras. Next weekend I'm shooting some star-and-landscape timelapse in the Oregon desert with a 5D, 20D, 350D, and the 24mm f/1.4.

[Dj Joofa]

Daniel, in general there is a trade off between resolution and dynamic range. However, it is not always clear how to achieve the most optimal trade off.

Again, true at the pixel level but not when viewing the image as a whole. Another illustration of the 100% comparison flaw: take a beautiful 12 MP image: the 100% crops look great and the 8x10 prints look great. Now resize it to 21 MP. Add just a little noise in photoshop, enough to be visible at 100%, but not enough to be visible in the 8x10 print. Print both at 8x10 and compare: they are identical. But at 100% crops, one looks worse than the other.

I don't think the above example is a good reflection of what you want to say. Consider this. You started with a 12 MP image, which had some spectrum, and you upsampled it to 21 MP. Now the upsampled image has a compressed spectrum in relation to the original 12 MP image, in addition to the replicas of the compressed spectrum. (The replicas don't concern us too much as you would going to get rid of them when you later downsize.)

Now you added noise to the 21 MP image. Typically noise will manifest itself as high frequencies and probably will do damage in the areas after (or starting nearby) the first compressed spectrum finishes. So at 1-1 at this stage you of course see that noise. Now you downsized. The downsizing will remove the noise you added, and stretch the compressed spectrum to more or less the same size back as you started.

You see the problem, you got back to where you started from. I don't think this is a good example. A real example would be when you start from a high-resolution image with noise, as in this case the noise spectrum is overlapping the signal spectrum, because the signal spectrum now is unmodified and not compressed in relation to some other image. Now you downsized. The downsizing will remove high frequencies and stretch the spectrum.

However, the difference here is that unlike the first case where the removed high-frequencies were mostly noise, in this case it is noise + some actual signal spectrum. Therefore, the image becomes a little blurred / smoothed, and that is the price you pay for downsizing.

Now that is a separate question that is the blurred downsized image still better in visual quality than a (smaller) sized image of the same size as the downsized image, i.e., acquired with a sensor with fewer number of photosites?