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02-10-2010, 12:46 PM   #76
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QuoteOriginally posted by er1kksen Quote
The relationship of filesize to storage space and computing power is a valid concern....

With the 7D, a workaround to this problem is using mRAW or sRAW. You get a reduced-resolution RAW file that's generally of higher quality than a RAW file from a camera with an equivalent native resolution. I was astounded at how good the 2mp 40D sRAW files looked (it made ISO 1600 actually usable!). When you need the full resolution, you can have it, but when you don't, you can have great 10mp or 4.5mp RAW files instead. Snip....
I have a lot of time for this viewpoint. I would like to shoot RAW all of the time on my K7, but I find that a 10mp Jpg is often going to give me more than I need.

However, the benefits of a 8bit file for PP work are not there - the K7 supports 12 bit (and remember the T2i will do 14-bit) - why can't I get a lossless converted file (m or S raw)?

"File sizes and write times, the unheralded casualties in the MP war"

02-10-2010, 01:21 PM   #77
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QuoteOriginally posted by Clarkey Quote
I have a lot of time for this viewpoint. I would like to shoot RAW all of the time on my K7, but I find that a 10mp Jpg is often going to give me more than I need.

However, the benefits of a 8bit file for PP work are not there - the K7 supports 12 bit (and remember the T2i will do 14-bit) - why can't I get a lossless converted file (m or S raw)?

"File sizes and write times, the unheralded casualties in the MP war"
Why? I don't know. That's a good question. Hopefully as pixel counts continue to rise, camera companies will wake up to the fact that such methods are necessary. Someday, I hope to be shooting 10mp reduced-raw files from a 30mp bayer sensor. The quality would probably blow the current 12-15mp sensors out of the water.
02-10-2010, 01:27 PM   #78
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QuoteOriginally posted by Clarkey Quote
However, the benefits of a 8bit file for PP work are not there - the K7 supports 12 bit (and remember the T2i will do 14-bit) - why can't I get a lossless converted file (m or S raw)?
One would think so.

However, a linear image file (what image files with RGB data are commonly called) compressed for 12 Bit resolution would be MUCH larger than a RAW file. Even at a smaller resolution. S-RAW starts to make sense when reducing the pixel count to 25%.
02-10-2010, 05:28 PM   #79
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Interesting

QuoteOriginally posted by falconeye Quote
One would think so.

However, a linear image file (what image files with RGB data are commonly called) compressed for 12 Bit resolution would be MUCH larger than a RAW file. Even at a smaller resolution. S-RAW starts to make sense when reducing the pixel count to 25%.

My understanding of this is a little limited, but with respect to s-raw, it is my understanding that the number of either photo sites sampled or pixels taken is reduced. I'm not sure exactly how that happens (and especially how individual RGB sites on a Bayer array are/ are not sampled).

But the main point was the reduced file size associated with Canon s-raw would be a nice to have, if it included the flexibility or reduced raw file sizes with retained file malleability.

02-10-2010, 05:46 PM   #80
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QuoteOriginally posted by Clarkey Quote
My understanding of this is a little limited, but with respect to s-raw, it is my understanding that the number of either photo sites sampled or pixels taken is reduced. I'm not sure exactly how that happens (and especially how individual RGB sites on a Bayer array are/ are not sampled).

But the main point was the reduced file size associated with Canon s-raw would be a nice to have, if it included the flexibility or reduced raw file sizes with retained file malleability.
Based on my experience with sRAW in the 40D, I don't think this is the case. Using sRAW provided a much higher level of pixel-level acutance (like you see with the foveon sensors) and significantly lower noise, leading me to think that its more of a pixel-averaging function.

Maybe I'd better get off my lazy bum and try to find some info...
02-10-2010, 07:46 PM   #81
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QuoteOriginally posted by er1kksen Quote
Based on my experience with sRAW in the 40D, I don't think this is the case. Using sRAW provided a much higher level of pixel-level acutance (like you see with the foveon sensors) and significantly lower noise, leading me to think that its more of a pixel-averaging function.

Maybe I'd better get off my lazy bum and try to find some info...
Here's all the info you need.

Inside the Canon RAW format version 2, understanding .CR2 file format and files produced by Canon EOS Digital Camera
02-10-2010, 08:29 PM   #82
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QuoteOriginally posted by Jodokast96 Quote
So let's see. I can get a DSLR that does video for $1000, or I can get an equivilent video camera for $50,000? Sorry, ain't buying it. You're getting far more than a larger sensor, DOF control, and interchangeable lenses for the extra $49,000, or you are just a total jackass for spending that much in the first place.
Even if the $50k (or $22k) camera gives you far more for the extra money, that's still completely out of reach for most people, it doesn't make the DSLR any less attractive.

QuoteOriginally posted by Jodokast96 Quote
There's nothing stopping these companies from putting the same guts from a DSLR in a better suited body, that, oh yeah, actually works like a video camera, instead of the half-assed way it does on a DSLR.
That puzzles me too. Maybe there is. Fact is this cheap cinema cam doesn't exist now. The first of it's kind will be the Red Scarlet (release in june), starting at 3k+.

I wonder why people get so upset about others asking for improvements in video. It's like we're stealing their right for better still quality instead
02-10-2010, 10:26 PM   #83
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Thanks for the link. Perhaps actually a little more information than I know what to do with. Still, from the gist of it, it sounds like my basic instinct wasn't far off... but that bit near the end about it possibly being encoded in YCbCr (which I just barely understand anyways) is very interesting.

I'm still wondering why on earth they didn't put the reduced-RAW modes in the T2i. An 18mp sensor in a camera aimed at the sub-$1k market really does need it.

02-11-2010, 12:52 AM   #84
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Well in a way, yes. There indeed are many more things to focus on in taking pictures than more pixels, higher ISO, frames/sec. Esp. when these involves trade-offs.

I can understand your position but what you can live with (larger files; slower processing) does not go well for everyone as can be seen from the responses in this thread.
I certainly print less and less nowadays and rarely very large if I do (maybe an A2 a few times a year). My most regular viewing medium is the 42" LCD TV sitting in my living room, which seems very happy with 1080p.
Perhaps this is an amateur (me) vs very serious amateur (you) difference in wants/needs.
I'd rather have very good high ISO performance, better DR and tweakable HDR. Maybe even a selectable ISO for specific portions of the sensor (imagine ISO 100 for skies and ISO 400 for the landscape all within a photo) if its even possible.


QuoteOriginally posted by er1kksen Quote
Interesting idea. Implying that only a newbie/consumer would be interested in things like higher ISO performance, higher resolution, fps, video resolution, and other general measures of performance, and that such things are useless to anyone who really knows anything about photography?

I would contend that there are plenty of photographers who understand and are willing to deal with the trade-offs (larger filesizes and their consequences) in order to get the higher quality images that result. I know I'm one of them. And it would be one thing if those were just empty numbers, but there is nothing to suggest that to be the case. The higher noise thing? It's largely a myth propogated by misinterpretation of image data and dXomark's poor rating system. Seriously, just go look at some samples. The 7D is now a known quantity. And that known quantity, specifically, is "the highest performing APS-C sensor available." I am a K-x owner and user, and as vaunted as my camera's little sensor is, I'm ready to acknowledge that the 7D is an even further step up. The proof is in the pudding; in this case, the pudding would be the final images, and that's all you really need to look at to see why a sharp 18mp and a good ISO 6400 without banding matters to photographers, not just consumer snap-shotters.
02-11-2010, 03:26 AM   #85
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QuoteOriginally posted by Clarkey Quote
My understanding of this is a little limited, but with respect to s-raw, it is my understanding that the number of either photo sites sampled or pixels taken is reduced.
There is no official information being published.

The following is some insider statement from some forum:
QuoteQuote:
sRaw is the original data resampled and redistributed in such a way that the resulting sRAW, with 1/4 the pixels of the RAW, have 1/2 as many samples as the original RAW, but with two of them in each pixel such that there are two types of pixels, green+red and green+blue, 30 bits each (I don't recall if it is 15+15 or not), in a checkerboard pattern.

They still need a form of demosaicing for the red and blue channels.
The problem is this:

The original RAW file contains monochrome pixels according to the Bayer pattern. They cannot simply be resampled to a smaller size (as it would be a gray image).

Therefore, there a two RAW formats which may contain a resampled image:

1. Linear DNG: the Bayer pattern is demosaiced and the resulting color values are losslessly compressed and stored in full bit depth.

The size of 1/4 #pixels Linear DNG roughly is 3/4 of the original RAW.


2. sRaw (1/4 #pixels) and mRaw (1/2 #pixels).

The size of sRaw is about 1/2 of the original RAW (and mRaw about 3/4). This slightly better compression capability comes at the prize of a remaining 2 color checkboard demosaicing (cf. quote above) which only Canon software (if at all) may be able to do properly. sRaw can lead to 1/4 size images which aren't as sharp as full size demosaiced images, then downsampled.


Personally, I couldn't care less about sRaw (being dead end special solutions) and look forward to downsampled (linear) DNG from cameras sporting 30 MPixels and more.


Another solution for lossy compression at higher bitdepths will be the forthcoming "JPEG XR" file format which will make the RAW file format redundant for many applications which now need RAW, like using fill color in post processing.

Last edited by falconeye; 02-11-2010 at 03:43 AM.
02-11-2010, 04:12 AM   #86
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At a cinema site I visit people seem excited about T2i

At a cinema site I visit people seem excited about T2i.
Can't please all the people but most seem happy except for paying more for 7D or even more for 5D Mark II.
The T2i seems to have best HD implementation, so far.

The new Canon 550D/ T2i…VERY powerful entry level HD-DSLR | Philip Bloom



Its arrival made me pull GH-1 out of my B&H shopping cart.
And GH-1 is down to $1189 with $850 kit lens included

http://www.bhphotovideo.com/bnh/controller/home?O=cart_accessories&A=details...=608940&is=REG







QuoteOriginally posted by ricardobeat Quote
Even if the $50k (or $22k) camera gives you far more for the extra money, that's still completely out of reach for most people, it doesn't make the DSLR any less attractive.



That puzzles me too. Maybe there is. Fact is this cheap cinema cam doesn't exist now. The first of it's kind will be the Red Scarlet (release in june), starting at 3k+.

I wonder why people get so upset about others asking for improvements in video. It's like we're stealing their right for better still quality instead
02-11-2010, 04:25 AM   #87
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It is funny how the article at Philip Bloom's site misses an important point:

It states that "the movie crop function is just another digital zoom".

Well, this isn't true.

In video mode, current entry level dSLRs do a subsampling of a fraction of pixels anyway. Therefore, to subsample the same number of pixels but from a center region doesn't decrease the image quality. It isn't digital zoom in the way the word is normally used.
02-11-2010, 05:12 AM   #88
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Philip is not a stills photographer, he's a cinema guy

Philip is not a stills photographer, he's a cinema guy.

Just an example of the people HD-Dslrs are attracting. People with no stills experience are buying Canon HD Dslrs and comparing them to Red One , Panavision, ect.


Look at the images in this post of his showing how cinemas guys are making do without spending $50,000 plus on real cinema cameras. Does this set up make sense for a stills shooter? I say No.

Canon has tapped into a very lucrative HD 1080 "Niche"


Filming interviews with DSLRs & recording sound separately and how to sync the bloody lot up! Also the advantages of IS lenses for them. | Philip Bloom



QuoteOriginally posted by falconeye Quote
It is funny how the article at Philip Bloom's site misses an important point:

It states that "the movie crop function is just another digital zoom".

Well, this isn't true.

In video mode, current entry level dSLRs do a subsampling of a fraction of pixels anyway. Therefore, to subsample the same number of pixels but from a center region doesn't decrease the image quality. It isn't digital zoom in the way the word is normally used.
02-11-2010, 05:19 AM   #89
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Here's a link to a video at Canon site

Here's a link to a video at Canon's site.

"Reverie"



Canon Digital Learning Center - Sample EOS 5D Mark II Video: Reverie
02-11-2010, 05:31 AM   #90
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His "Nocturne" video

His "Nocturne" video

This was shot with only available light, at night !


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