# digic 4 vs digic 5



## theregoesjb (Dec 6, 2011)

any knowledge and/or opinions on how big of a difference there is between the two?


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## whatta (Dec 6, 2011)

"The PowerShot S100 features the most powerful implementation of the HS System yet. Building on the PowerShot S-series' reputation for providing high-quality, low noise images in low light, the enhanced HS System optimally combines DIGIC 5 processing with a high-sensitivity 12.1 Megapixel 1/1.7-type CMOS developed using Canon EOS sensor know-how â€“ providing an even more powerful basis for low light photography. Supporting a maximum ISO of 6400 at full resolution, the camera fully-utilises the high performance of the CMOS sensor and the power of DIGIC 5 to reduce image noise â€“ offering the reassurance of excellent image quality in all conditions.

Designed to achieve new and advanced levels of image quality, DIGIC 5 analyses four times more image information to create each pixel, recording more detail and colour from a scene than ever before. Processing speed is also six times faster compared to the previous processor, efficiently managing the increase in scene information and simultaneously reducing the appearance of image noise by up to 75%

Using the power of the DIGIC 5, the PowerShot S100 is ideal for capturing fast-moving action. High-speed Burst HQ is perfect for everything from sports to parties, capturing a rapid sequence of eight full resolution shots at up to 9.6 shots/sec. For recording the drama of high-speed action, Super Slow Motion Movie mode also records videos at 240 fps (QVGA quality) or 120 fps (VGA quality).

For easy shooting in a range of situations, Canon's Smart Auto mode ensures great results by selecting the optimum settings for a scene from 32 variables. New Multi-area White Balance also makes images look more natural by detecting scenes with two different light sources and applying area-specific white balance correction. For instance, when shooting a portrait with flash under tungsten lighting, the camera will simultaneously apply tungsten white balance to the background and flash white balance to a person's face, ensuring both the subject and background look natural."


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## neuroanatomist (Dec 6, 2011)

Note that there are two 'flavors' - Digic5 and Digic5+.

The new Digic 5 processor is 6X faster and creates 75% less noise than the Digic 4 processor.

Compared with the predecessor, Canon's DIGIC 4 Image Processor, the Dual DIGIC 5+ Image Processor offers approximately 17x faster processing speed, and feature new algorithms that promote greater noise reduction at higher ISOs.


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## awinphoto (Dec 6, 2011)

neuroanatomist said:


> Note that there are two 'flavors' - Digic5 and Digic5+.
> 
> The new Digic 5 processor is 6X faster and creates 75% less noise than the Digic 4 processor.
> 
> Compared with the predecessor, Canon's DIGIC 4 Image Processor, the Dual DIGIC 5+ Image Processor offers approximately 17x faster processing speed, and feature new algorithms that promote greater noise reduction at higher ISOs.



Neuro... in a prior thread you mentioned that the ADC creates/applies the noise whether it be analog or digital depending on ISO and the digic just processes the files to create the cleanest files possible given the situation... Given the above statement about the digic creating the 75% less noise compared to digic 4, I'll take it that this is Noise Reduction, but would it also be an improved ADC as well to work in conjunction allowing a 75% reduction in noise or ?


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## Meh (Dec 6, 2011)

neuroanatomist said:


> Note that there are two 'flavors' - Digic5 and Digic5+.
> 
> The new Digic 5 processor is 6X faster and creates 75% less noise than the Digic 4 processor.
> 
> Compared with the predecessor, Canon's DIGIC 4 Image Processor, the Dual DIGIC 5+ Image Processor offers approximately 17x faster processing speed, and feature new algorithms that promote greater noise reduction at higher ISOs.



Does Canon include in the definition of "DIGIC" the ADC or any analog signal processing chips or does "DIGIC" only refer the digital processor?

If it's only the processor, then would any claimed reduction in noise only be due to the application of noise reduction algorithms which are only applicable to the production of an in-camera JPEG?


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## whatta (Dec 6, 2011)

> Does Canon include in the definition of "DIGIC" the ADC or any analog signal processing chips or does "DIGIC" only refer the digital processor?



I _guess_ it is only the processor and they consider the ADC to be part of the sensor.


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## thejoyofsobe (Dec 6, 2011)

heard a bit about multi-area white balance with the S100 and assumed that was going to be in every Digic 5.

my googling skills have not produced any real world shots showing the results. i also wonder if eventually in RAW we'll be able to tweak the individual white balance areas or whether this multi-area white balance feature is available only on JPEG.


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## gene_can_sing (Dec 6, 2011)

I do mostly video and I saw a test clip of the new Canon point and shoot that uses Digic 5. Even this cheap camera had noticeably cleaner video than the current Digic 4 DSLRs. It appeared to have less noise, no moire and overall a more solid video picture.

But I did only see one clip so can't make a clear judgement.


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## Ryusui (Dec 6, 2011)

Here's a good example of the difference between the two processors:
The Canon S95 with its DIGIC 4 processor, a 10.0 Megapixel camera, must reduce the camera's quality to 2.5 Megapixels to be able to shoot at 3.9 shots per second in continuous burst mode. At full 10 Megapixel quality, it shoots 1.9 shots per second.
The Canon S100 with its DIGIC 5 processor, can shoot 2.3 shots per second regularly, but is able to hit a speed of 9.6 shots per second, both at a full 12 Megapixels.

Keep in mind, however, that while the S100 can hit a *speed* of 9.6 shots per second, it really will only capture a maximum of 8 actual pictures per burst. But still, even at 8 frames with 12 Megapixels on a point and shoot...that's impressive.


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## Meh (Dec 6, 2011)

gene_can_sing said:


> I do mostly video and I saw a test clip of the new Canon point and shoot that uses Digic 5. Even this cheap camera had noticeably cleaner video than the current Digic 4 DSLRs. It appeared to have less noise, no moire and overall a more solid video picture.
> 
> But I did only see one clip so can't make a clear judgement.



Makes sense. Video output is highly processed/encoded I think and much more compute intensive than image processing... video has more processing involved and a much higher frame rate. Therefore, noise reduction algorithms might not be the priority and could be limited to the simplest routines that can be done quickly.


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## neuroanatomist (Dec 6, 2011)

Digic does not include the ADC. But RAW isn't really raw, right? For example, long exposure NR subtracts a dark frame but writes out the RAW image as a single file (and obviously the original data from the shot are modified). Nikon reportedly clips off the bottom 5% of the signal (which is almost all noise anyway) before writing a D3/D300 RAW file, and with long exposure NR also applies a median blur filter that can't be disabled (so astrophotographers have to shut down the camera during dark frame capture as a workaround). Point is, the data are converted from analog to digital, then sent to Digic/Expeed, then sometimes 'cooked' in undisclosed ways before the RAW file is written. So, there _could_ be digital NR being applied to the RAW data to account for some of the improved ISO noise performance of the 1D X, for example.


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## donthasslethehoff (Dec 6, 2011)

Anyone with insight on how the new DIGIC chip compares to what Sony just came out with? I've been with Canon since 2005, but frankly, if the new Rebels can't match what Sony can do with phase detection af for video, I may jump ship.


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## Mt Spokane Photography (Dec 6, 2011)

donthasslethehoff said:


> Anyone with insight on how the new DIGIC chip compares to what Sony just came out with? I've been with Canon since 2005, but frankly, if the new Rebels can't match what Sony can do with phase detection af for video, I may jump ship.



The sony phase detection system for video is not determined by the processor, but by the entire design. Before you buy a Sony DSLR for video, be sure you understand its limitations. If you want to use phase detect autofocus, you can only shoot at F:/3.5, for example. This is better than nothing, but lots of buyers do not check carefully, and are disappointed in video with a Sony DSLR. There are ISO limitations as well, so everything is a trade off as usual.


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## Meh (Dec 6, 2011)

neuroanatomist said:


> Digic does not include the ADC. But RAW isn't really raw, right? For example, long exposure NR subtracts a dark frame but writes out the RAW image as a single file (and obviously the original data from the shot are modified). Nikon reportedly clips off the bottom 5% of the signal (which is almost all noise anyway) before writing a D3/D300 RAW file, and with long exposure NR also applies a median blur filter that can't be disabled (so astrophotographers have to shut down the camera during dark frame capture as a workaround). Point is, the data are converted from analog to digital, then sent to Digic/Expeed, then sometimes 'cooked' in undisclosed ways before the RAW file is written. So, there _could_ be digital NR being applied to the RAW data to account for some of the improved ISO noise performance of the 1D X, for example.



Good points. Absolutely, they could be cooking the RAW data but if so I'd expect that it's minimal in the sense that they would not apply any aggressive NR techniques that use heavy "nearest neighbor" averaging due to the image softening. But they could be doing it without admitting it... would Canon do that? 

The two you mention... dark frame subtraction and clipping the lowest signals aren't too bad and don't apply averaging to all pixels. There are other types such as double sampling to measure the reset noise (charge left over from previous image after the pixels are reset) but I think that's already being done.


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## funkboy (Dec 7, 2011)

gene_can_sing said:


> I do mostly video and I saw a test clip of the new Canon point and shoot that uses Digic 5. Even this cheap camera had noticeably cleaner video than the current Digic 4 DSLRs.



Bear in mind that Digic 5 is the first Digic generation to be designed from the ground up for dealing with HD video and stills processing in the same camera. Also, given that you're talking about a P+S be sure to evaluate the detail of the image as consumer stuff tends to be pretty heavy-handed on the NR by default...


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## Edwin Herdman (Dec 7, 2011)

neuroanatomist said:


> Nikon reportedly clips off the bottom 5% of the signal (which is almost all noise anyway)


Hmm? 

Anyway - from the standpoint of the photographer, it makes no difference whether the ADC is integrated into the DIGIC (which I think it is), or on the sensor, or whether it is a separate component altogether. It offers Canon part reduction and speed advantages to incorporate it either on the sensor or the DIGIC, but that is more or less invisibly done.

For what it's worth, some online commentators state that TI makes the ADC; others (Thom Hogan) state in places that "some ADCs" do some processing. It's a case of half a dozen, six the other.


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