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Messages - curby

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16
To reiterate, the goal is smaller final images anyway: I wonder what thkn's images would look like if they were all resized to SRAW size.  Would the resizing lessen the perceived chroma noise of the full RAW images?  From those limited tests, I'm not seeing a lot of benefit to the full RAW (such as greater detail), and the reduced chroma noise of the SRAW images seems like a pretty compelling benefit.  Of course, that goes against what most people here are saying: namely, that shooting SRAW does NOT offer such advantages. 

Thanks for the tests!  I might have to do my own testing when I upgrade my body to something that can do smaller RAWs. 

17
IF Canon did it right you get free image stacking (4 images) which should result in less noise and better color reproduction

^ This is the crux of my question: if I don't need the full sensor resolution anyway, maybe doing (some of) the downsizing ahead of time results in a better final image.  It all depends on the specifics of how RAW and sRAW actually map sensor sites to the file.

Relatedly, does anyone know whether Canon's RAW format stores post-interpolation RGB pixels, or does it separately store the red, green and blue data as pre-interpolation discrete readouts?  If the latter, whatever smarts could have been applied to the sRAW should still be applicable to the full sized RAW image.

18
EOS Bodies - For Stills / Do smaller RAW formats give lower noise?
« on: July 09, 2013, 01:17:17 AM »
tl;dr version: I'm really interested in low noise during low-light/high-ISO shots, and am wondering if shooting in smaller RAW formats could help in that effort.

I'm betting it doesn't work, but what does shooting in smaller RAW sizes (e.g. M-RAW, S-RAW) actually do in terms of mapping sensor sites to the final image, and can it combine sensor site outputs to increase apparent light sensitivity without boosting ISO?  And if not, why not?

Example: take a 20 megapixel sensor, intelligently combine the readings of each block of 2x2 red, green, and blue neighboring sensor sites, and spit out a 5 megapixel image.  If that's done closer to the sensor, before the interpolation of subsensor sites into RGB pixels, might it result in a better (e.g. lower noise) result?  The idea would be to discard the outputs of aberrant sensor sites before they could muddy the interpolation algorithm and "dirty" more final pixels.  I wonder if that would be better than taking a full resolution image, applying noise reduction post-processing tools, and spitting out a 5 megapixel image at the end of the workflow.

Any thoughts?  Anyone actually know how sensor sites are mapped onto S-RAW and M-RAW image pixels?  Thanks!

19
Lenses / Re: Photozone spanks the 24-70 F4 USM L IS
« on: March 06, 2013, 08:32:10 PM »
I agree with the above, with two caveats/clarifications:

1) Apple has more than its share of rabid fans, but it's not just the media that has insanely high expectations of them; their users howl about every real and perceived fault.  I'm a long-time Mac user, and have caused many friends and family to purchase them too, but boy do I hate their mice, cloud services, and every laptop screen they've ever put out before the retina.

2) The market will bear what the market will bear.  Going back to Apple, everyone said the iPad mini was overpriced, but they still couldn't keep them in stock.  Lowering the initial price would have just been a bad business decision that would have left money on the table.  $30 for a Lightning cable is a lot, but now there are cheaper options available.  $1500 for this lens is a lot, and will either plummet in price if the naysayers here are right, or will stay high if it does turn out to be as popular as Canon bet on.

Ultimately, I hope the performance problems Photozone found are limited in nature, as supported by other reviews not mentioning the problem and other users who can't reproduce the problem.  If not, then Canon truly made a misstep not only in the pricing, but in releasing a lens that simultaneously offers high-magnification performance as a headlining feature yet suffers from critical issues when using that feature. 

20
Lenses / Re: Photozone spanks the 24-70 F4 USM L IS
« on: March 05, 2013, 11:19:42 AM »
See his Tamron 24-70 IS ... review


Do you have a link?  This page doesn't seem to have many details.  Thanks!

21
Lenses / Re: Photozone spanks the 24-70 F4 USM L IS
« on: March 05, 2013, 01:13:16 AM »
It's a deal breaker for me. I have zero interest in a lens with focus shift problems.


Sure, but does the lens have focus shift problems?  A refresher:

the focus shift issue which I haven't seen mentioned anywhere else thus far


I wonder why that hasn't been all over the internet already! Maybe sample variation did play a role here?  ???


Here are some reviews and hands-on previews, all of which fail to mention any sort of fous shift issue with the lens.  Is everyone else's testing methods so non-rigorous that they miss this problem, is it in fact not a problem during real life use of the lens, or did photozone get a bad lens?

http://www.lensrentals.com/blog/2013/01/canon-24-70-f4-is-resolution-tests *
http://www.the-digital-picture.com/Reviews/Canon-EF-24-70mm-f-4-L-IS-USM-Lens-Review.aspx
http://www.dpreview.com/previews/canon-ef-24-70mm-f4l-is-usm/
http://www.photographyblog.com/reviews/canon_ef_24_70mm_f4_l_is_usm_review/
http://www.ephotozine.com/article/canon-ef-24-70mm-f-4l-usm-lens-review-21291
http://www.kenrockwell.com/canon/lenses/24-70mm-f4.htm **


22
Lenses / Re: Photozone spanks the 24-70 F4 USM L IS
« on: March 04, 2013, 07:15:22 PM »
OK, I'm getting really confused now.  Here are some reviews and hands-on previews, all of which fail to mention any sort of fous shift issue with the lens.  Is everyone else's testing methods so non-rigorous that they miss this problem, is it in fact not a problem during real life use of the lens, or did photozone get a bad lens?

http://www.lensrentals.com/blog/2013/01/canon-24-70-f4-is-resolution-tests *
http://www.the-digital-picture.com/Reviews/Canon-EF-24-70mm-f-4-L-IS-USM-Lens-Review.aspx
http://www.dpreview.com/previews/canon-ef-24-70mm-f4l-is-usm/
http://www.photographyblog.com/reviews/canon_ef_24_70mm_f4_l_is_usm_review/
http://www.ephotozine.com/article/canon-ef-24-70mm-f-4l-usm-lens-review-21291
http://www.kenrockwell.com/canon/lenses/24-70mm-f4.htm **

* Roger mentions that his writeup specifically did not deal with focusing issues, but I imagine he would have mentioned something if he discovered a glaring problem.

**  :-X

23
Lenses / Re: Photozone spanks the 24-70 F4 USM L IS
« on: March 04, 2013, 06:26:13 PM »
So does anyone remember the wide open LoCA shot for the Photozone review of the Tamron?  It shows the same softness that plagues the Canon:

http://www.photozone.de/images/8Reviews/lenses/tamron_2470_28_eosff/loca_f28.jpg

Why was that not called out as a fault during the Tamron review?  I think I'm missing something here because it seems like a very similar problem, but it wasn't discussed as such in the Tamron review.

On the other hand, I cannot imagine a situation where I set the aperture AFTER focusing, so I don't see a big issue here.


Oh, is that all it was?  I thought that when you stop down to say f/8, the camera is still doing focusing with the lens wide open.  It's not until you click that the lens stops down to f/8, effectively changing the aperture after focusing.  What's really going on here?

people seem to just enjoy hating the 24-70 IS.


That just makes it the perfect kit lens for the well-hated 6D.  ;D

24
Lenses / Re: Photozone spanks the 24-70 F4 USM L IS
« on: March 04, 2013, 05:51:50 PM »
Interesting results, to be sure.  This lens, along with the Tamron 24-70/2.8 VC, are frontrunners for replacing my 17-55/2.8 IS if I end up going full frame later on this year.  Seems like I'd be trading focus shifting and smaller aperture for portability (smaller lens, and I probably wouldn't need a dedicated macro). 

Odd that the review didn't really mention macro performance too much, and none of the sample shots show a close focus situation.  I guess the LoCA section is meant to cover that.

RLPhoto: Macro means a large magnification, and for a non-dedicated Macro lens this qualifies handily.  The "all-in-one" nature of this lens means I can carry a smaller, lighter kit, and that's precisely why it's even in the running besides the otherwise superior Tamron. 

In the end, the focus shift issues and price are two sides of the same problem.  With great resolution, amazing versatility, compact size, and durable construction, I wouldn't mind paying the asking price if it focused more reliably at macro ranges.  On the other hand, I could allow for such quirks if they asked less.  The combination of the two makes it a hard pill to swallow though.

25
Pricewatch Deals / Re: Deals: Canon EOS 5D Mark III & Canon EOS 6D
« on: March 04, 2013, 05:23:31 PM »
I think that's a bit of a loss for everyone.

I prefer the paper specs of the 24-70 f/4 L with near-macro capability, largely due to the near-macro capability.  I'm just a little unsettled by the bad quality reports people have given, but those reports don't seem consistent either.  Hmm.

26
B&H sells plenty of stuff that doesn't belong here, and to be honest I'd count laptops among them.  I'd rather this sort of thing not clutter up the main page (for example, macrumors used to have a "back page" for less relevant stuff) but it's not horrible enough for me to stop following the blog.

27
Reviews / Re: Canon 6D review
« on: January 05, 2013, 11:08:29 PM »
I think you may have misread my review (or I wasn't very clear). The 5D IIIs AF is excellent and fast in all situations - including low light. Very low light is obviously more of a challenge but mostly it locks fine. The 6D however has a slightly better centre point in near darkness - it locks a bit quicker and doesn't seem to hunt at all (yet).

Thanks for the clarification, but it was actually others in this thread that were complaining about the 5D3's low light focusing performance.  =)

28
Reviews / Re: Canon 6D review
« on: January 02, 2013, 04:19:29 PM »
The two biggest considerations for planning my next body are bulk and AF performance with both moving and low-lit subjects.  I had heard that the 5DIII tracks moving subjects very well, but not that it's horribly slow in low light.  The dpreview.com review of the 5DIII seems reasonably satisfied with its low light focusing speed and accuracy, though I understand it's just one opinion based off limited experience so it should be taken with a grain of salt.

If the 5DIII really has trouble in low light, that's a pretty serious blow against it, and would bias me strongly towards the cheaper and lighter option.  Of course the number, utility, and coverage of the 6D's AF points can't compare to the 5DIII's, but speed in low light matters to me as well. 

All that said, I'm coming from a 400D/XTi, which is one of the reasons I'm concerned about size and weight.  Would any aspects of either of these autofocus systems seem like a step down compared to the Rebel?  E.g. do the 6D's AF points actually cover a smaller portion of the frame compared to the Rebel's 9 points? 

29
Software & Accessories / Choosing/Stacking ND Filters
« on: December 21, 2012, 04:30:11 AM »
I'm considering getting the B+W 3-stop and 6-stop NDs, and just stacking if I need more light loss.  I get that you shouldn't stack filters if you can help it.  But if it's the choice between two better quality filters (say a 3-stop and a 6-stop that could approximate a 9-stop ND filter) and three poorer quality filters (say a set of 3-, 6-, and 10-stop filters) that cost about the same, could the inherent quality of the better filters make stacking less horrible? 

Also, how good are variable ND filters? "I heard on the Internet" that the interactions between the two polarizers can cause rough light gradients that should otherwise appear smooth.  Plus, you've got 4 surfaces from the two polarizers anyway, so can IQ really be any better than stacking two high quality fixed ND filters?

Any other thoughts or experiences on how you configure your ND capability would be great.  Thanks!

30
I upgraded to the 6D, and I miss my 17-55/2.8 IS.


Well, crap: http://www.canonrumors.com/2012/12/ef-24-70-f2-8l-is-exists-as-a-working-prototype-cr2/

I'm not sure I can wait until 2014 to upgrade.  :P

Also: noticed you're like me with the tripod habit of not carrying it.  That's one of the reasons I like IS/VC/OS.  I'd seriously consider IS despite it narrowing the lens options.


Yup.  If I were a pro and were paid to have "serious" equipment around, and I regularly went out with the primary goal of shooting photographs (rather than other goals such as seeing the sights or having fun with family), and I didn't have foot issues, I'd be more inclined to carry more gear.  And just to be clear, it's not just the weight but the size, as well as time and floor space needed to set up/break down support equipment, that really adds up.  Monopods help with some of those issues, but IMO not enough. 

Thanks again for the ideas, everyone.  2013 will be an interesting year for my gear bag, I can tell.

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