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Messages - Aglet

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331
Reviews / Re: Why the DxO bashing?
« on: February 08, 2014, 10:36:35 PM »
@ JR
That's really interesting about Nikon and how they handle their black levels.
I remember seeing samples when their first "lord of the dark" came out, D3 or D3S?...  and I could see the black levels were clean but certainly looked artificially so.
In comparison, I'm finding the more recent Nikon output to be more realistic in that area, at least for my purposes, but I've never tried astro' so this is really quite interesting and something I'll have to look in to when I can.

Thanks, also, for the reminder and links to Roger Clark's site.  I'm glad he's keeping it updated (unlike mine) so will have to spend some time reading there as well.

And yes, laugh as some may about it, I can garner a fair bit of useful info very quickly from a "dark shot" by pushing it 4 stops and looking at the noise patterns.  It tells me immediately what to expect if I have to push a file from it.

332
Reviews / Re: Why the DxO bashing?
« on: February 08, 2014, 10:21:27 PM »
What I find really interesting is when the DR/FPN Evangelists are actually challenged with an image that squarely disputes their assertions religion, they all ignore it.

hmmm?? Don't get "FPN"?
Fixed Pattern Noise

333
Reviews / Re: Why the DxO bashing?
« on: February 08, 2014, 10:12:55 PM »
What fact am I distorting?

"And with Canon equipment, you're at about 10 stops of usable dynamic range."

less, actually, if you are choosing high standards of SNR then only 8 or 9 stops for the 5d3 accordin' t' I-R

www.imaging-resource.com/PRODS/canon-5d-mkiii/Z000100_ACRman1_Step_2.png

edit:  jeez, I don't know if that can be right, that really sucks! :P

334
Reviews / Re: Why the DxO bashing?
« on: February 08, 2014, 09:45:40 PM »
That's a good explanation on the previous page JR, thanks for posting that for those who need it.

The only thing I'd add to that even if we know the RMS (or averaged) read noise numbers used for their base DR calculation, we would still have no clue as to HOW UGLY lifted shadows will look.  That's what pushed-4-stops-lens-cap-on shots are for! :)

If DxOmark would publish the peak-to-peak read noise, and they'd still likely have to do a compromise of that, or add a read-noise histogram to be more thorough, then we would have a more clear indicator of whether that noise is random in nature, and therefore subjectively less bothersome, or patterned, and therefore  more difficult to mask.

E.g.  In the case of the 7Ds I looked at, alternating vertical bands of (8 per, i think) pixels had different levels of read noise and this produces obvious stripe artefacts when lifting shadow areas. Since the ratio of read noise to signal there is already very low the read noise difference is made obvious.
In some other cameras the read noise is more uniformly distributed and is less obvious when lifting shadows.

Imaging Resource provides a different way of presenting the DR measurement, by providing DR figures at different signal to noise ratios, still likely based on RMS read noise, but it provides more of a spread of figures which can be helpful and they also publish more noise data as well, including individual RGB curves.

Here they are for the 7D, and the tiny-sensored Pentax Q.

www.imaging-resource.com/PRODS/E7D/Z00100_ALO_OFF_acrauto_Step_2.gif
www.imaging-resource.com/PRODS/PENTAXQ/Z0125_ACRauto_Step_2.png

Even I'll say I'd take the 7D's file over the Q's file for lower overall (BER) noise on a real image - at least until I wanted to lift shadows, where the tiny Q's lack of FPN can then show the 7D how that's done.

http://a2bart.com/tech/allcamdknz.htm

Then throw in unit-to-unit variability and improvements that may be made during the mfg run of a given body and there are more things to argue about.   For instance, my late model 40D, a model initially reputed to have some noise issues, provides noticeably less FPN in pushed files than my early production 7D or early 5D2 did, yet some claim noisy 40Ds and clean 7Ds or 5D2s.

So, back to DxOmark - or any site that does not define how they make those measurements or what baselines they use, even the uninterpretted the data provided is less than ideal or conclusive. (But it's still more informative than "real world pictures" for such matters)
The best rough data from DxOmark on this is the FULL SNR curves because you can see how each sensor performs at each ISO and at a lot of different levels from dark to white levels.
/editorial

335
Reviews / Re: Why the DxO bashing?
« on: February 08, 2014, 09:41:25 PM »
There, do you feel better now?

Does your distortion of facts, either through intentional obfuscation or simple lack of comprehension, make you feel better?  I just see it as rather sad and pathetic...

^-- Seriously --^

I....WOW....just WOW.... ???
+1

336
Reviews / Re: Why the DxO bashing?
« on: February 08, 2014, 05:46:26 PM »
If you are shooting static subjects, how hard is it to bracket and merge to 32bit in photoshop and get all the DR in the world with even the worst camera.

And if you shoot moving targets, how often do you actually use iso 100 which is where this advantage actually exists? I at least virtually always use much higher ISO to freeze motion and well at high ISO it is actually Canon that got the best DR according to DXO.

I find it funny when I hear this too.

Even a landscape can have dynamics that prevent working around DR limitations by bracketing and merging.
If it's small and static, then it can be lit to fix it... unless it's not practical, you know, like outdoors.
So these workarounds aren't always viable either.
Then you shoot something else that you can shoot.  For most of us, that's just not a huge disaster.  The reality is that this whole DR argument is pretty much a non starter an any practical sense. 

As I said earlier, if it were the huge issue that people like yourself seem to think it is, nobody would buy the equipment but that isn't really what we see in the real world, now is it?

altho I participate in, I'm not ON the DR bandwagon.
My peeve is FPN, which contributes to low DR; a different but directly related issue.
I have low DR cameras that don't have serious FPN problems, I still like and use them. (e.g. Oly E410, Pentax Q)
Too many here seem to conflate and confuse FPN and DR when those issues can, and often should, be considered separately for their effects on an image.

337
EOS Bodies - For Stills / Re: 7D vs. 70D: Which has better image quality?
« on: February 08, 2014, 04:26:41 PM »
You react here claiming you have tested 70Ds (plural!) and draw conclusions based on your testing regarding the difference in noise between the 70D and the 7D.
That might be useful information. When I ask about your test results you come up with a set of lens cap shots pushed 4 stops of a single 70D that most likely never left the shop you tried it at and no 7d results to compare them with.
That’s a bit meager, don’t you think?

for the price? ;)
if you visited my website, you will also find a page dedicated to comparing read noise from a large number of cameras, including the 7D
I've got about 10 other bodies, 70D included, which are still waiting for me to get the time to prepare and add to that page, including some older models.

I have enough data on the 7D and 70D to satisfy my curiosity and I believe I've adequately summarized what I've found, if subjectively, in that CR post.

From all those who claimed to have a 7D (or 5D2) that does not have a pattern noise problem, none have offered or supplied a requested raw file for me to compare.

And the only way those bodies leave the shop is if I pay for them.  That kind of research doesn't come cheap.
If someone wants to sponsor more testing, I'll consider it.  I do enough on my own dime & time.

The web site so many love to hate, DxOmark, provides plenty of basic data for everyone to review and interpret.

www.dxomark.com/Cameras/Canon/EOS-70D---Measurements
www.dxomark.com/Cameras/Canon/EOS-7D---Measurements

Have a look at the FULL SNR tab and compare for yourself.
There really isn't much of an obvious difference between the two bodies, especially in the low ISO shadow region.
But DxOmark does not publish anything on the nature of the measured noise; whether it's random, or patterned.
Visualizing the noise the way I present it provides an opportunity to decide whether the camera's pattern noise characteristic might be an issue for some users.
Compare it to audio; what's easier to tolerate in a quiet music passage, a faint white noise or a discrete 60 Hz hum?

 
Quote
your conclusions are derived from the one thing Canon falls short at and that is low ISO dynamic range...no matter how good the rest of the performance is. 

I'll give Canon an approving pat on the head for everything else they've accomplished.  Truly, I enjoy using their gear and still retain some.
But I really hope they can pull up their socks a little more on the low ISO
PATTERN NOISE PROBLEM. 
DR is NOT what I've been complaining about, PATTERN NOISE is what I've consistently had problems with from Canon's sensors and specifically, DIGIC 4 systems.

Fixed pattern noise is a direct factor in DR measurements, but they are different problems to deal with when producing a final image.

 
Quote
It seems you only like to focus on the low iso part as far as image quality is concerned. I can even understand for some highly specialized photographers having more than 12 stops DR at low iso is important. If so, don’t waste your time on the current offerings from Canon. Buy a D800 or an A7R if you are on a budget or a good medium format camera if low ISO performance is crucial. 

I did exactly that - because every Nikon, Pentax and now Fuji and Olympus body I've added to my inventory lacks the one thing I get only from a digic-4 Canon.
FIXED PATTERN NOISE at low ISO .. that fouls up shadow (and sometimes even midtone) areas and limits manipulation of those areas in post without requiring inordinate amounts of time and compromises to correct.
I should not have to waste time in post to fix problems that are innate to the camera; I prefer tools that don't require me to work harder to achieve something so I choose those that don't have deficiencies where it matters to me.
The newer digic 5 products have improved on the FPN issue, just not yet enough to convince me they will outperform my current tools, as either a sensor or a system.
The 70D's sensor performance is no longer much of a limitation compared to the competition, unlike previous digic-4-based canon bodies. And I say that based on the improved FPN performance, not overall DR.
The low ISO DR is still lower than competitors but, with the shadow noise now more random, it's not as much of a post-processing problem as it was when the shadows looked like a picket fence of stripes if pushed, a'la 7D.

 
Quote
Then I visited the website .. you don’t even have to pay me for this great idea. 

I'm fairly sure "Canon Plaid" or "Canon Stripe" will not catch on as wall art...  But I've been wrong about mass market appeal before.
Do you think Nikon, Sony, Pentax, Fuji, film or Oly fans would buy large prints of that?  After all, they can't produce that kind of art with their cameras.
Hmmm... Maybe you're on to something after all.

338
Reviews / Re: Why the DxO bashing?
« on: February 08, 2014, 04:16:03 PM »
If you are shooting static subjects, how hard is it to bracket and merge to 32bit in photoshop and get all the DR in the world with even the worst camera.

And if you shoot moving targets, how often do you actually use iso 100 which is where this advantage actually exists? I at least virtually always use much higher ISO to freeze motion and well at high ISO it is actually Canon that got the best DR according to DXO.

I find it funny when I hear this too.

Even a landscape can have dynamics that prevent working around DR limitations by bracketing and merging.
If it's small and static, then it can be lit to fix it... unless it's not practical, you know, like outdoors.
So these workarounds aren't always viable either. 

340
EOS Bodies / Re: Best Sensor Cleaning Products
« on: February 06, 2014, 11:04:49 PM »
My local Pentax rep demonstrated a gel-stick sensor cleaner to me 2 years ago.. at least.  Kinda like the sticky gel lint roller material for stuff a blower won't remove,.
For gobs of oil on my FF Nikons I've used a simple cotton swap on a stick.  works great if you're careful.
I won't tell you what else I use, it'll cause you nightmares.

341
Reviews / Re: Why the DxO bashing?
« on: February 06, 2014, 11:03:43 PM »
Many Canon devotees may also experience sour gripes that those DxOmark base ISO sensor measurements consistently demonstrate Canon's ~2 stop weakness no matter how expensive a body you buy.
Which leads to much knashing of keyboards as staunch Canonites defend their choice to use such gear and providing many valid reasons and lame excuses why it doesn't matter that a $400 entry-level Nikon DSLR has better low ISO performance than any canon DSLR.
Just watch. ;)

As for DxOmark's single numerical score, mostly useless.
Their raw measurements, however, provide a lot of useful and easy to compare information on sensor performance.  As do their lens data, just do your own comparisons.

342
EOS Bodies - For Stills / Re: 7D vs. 70D: Which has better image quality?
« on: February 06, 2014, 01:15:50 AM »
You’ve tested sevral 70Ds?
In a lab or in the field?
Can you show some of your test results? I like to see the “real world” difference between the 7d and 70d and if there is any copy variation between the 70ds.

This will have to suffice

www.canonrumors.com/forum/index.php?topic=16713.0

otherwise it's $280/hr + incidentals for custom work.

Quote
By the way, “noise metrics” do not only apply to iso’s below iso 1600. Above iso 1600 Canon is on par or preforming better.

yes, it's certainly comparable at the high end... FWIW, even compared to the MFT sensor in the -EM1.
comparison image for editorial purposes from DPreview.com

edit - oops, don't look at the Fuji results.

343
Third Party Manufacturers / Re: FUJIFILM'S latest, X-T1 ?
« on: February 06, 2014, 12:54:01 AM »
Big sale on Fuji lenses starting on Feb 9:

http://www.fujirumors.com/leaked-all-xf-lens-and-x-body-deals-paper-now-on-fujirumors/
Great to see.  First they generate a fair bit of buzz with their products and now they're making them much more appealing in price.
I've already nabbed some great deals on bundles even before xmas.
Will blow more $ in their direction before the deals end.  I'd like a bit more OEM glass.

344
Third Party Manufacturers / Re: FUJIFILM'S latest, X-T1 ?
« on: February 06, 2014, 12:48:27 AM »
I'm looking forward to playing with the Xt1's manual controls and seeing how they interact with the 2 standard electronic control wheels and what sort of customizing and functional crossovers may be available.
Many of Fuji's lenses have aperture rings that also sport an "A" so you can set it there and use one of the electronic control wheels to manage the aperture with your right hand without lowering the camera or doing any fancy hand contortions.
I'd like a toggling lock button for the ISO wheel; tho with the Fuji, you can pretty much leave ISO in auto and let it take care of it according to your auto-iso preference settings.
There are still some compromises, for sure, but this is looking like a very fun and flexible camera to use in a variety of scenarios.

345
Third Party Manufacturers / Re: FUJIFILM'S latest, X-T1 ?
« on: February 05, 2014, 01:58:20 AM »
Money did the talking for me this time, X-e1 with the kit zoom for only $800 is a bit easier for testing than the $1300 xe2 equivalent kit.  the difference will get spent on a 35mm f/1.4 lens and maybe an extra battery.

I tried both cameras with the same lenses at my local dealer in bright and dim light.  The xe2 was slightly quicker to AF in low light and it gained-up the EVF much better but they both seemed to quit working at about the same level of low light and low contrast - hard to tell when in a hurry but I think the xe1 will suffice for most of my slow-paced shooting.  Expanding the AF frame size helped in low light, FWIW.
From my reading it seems the AF pixels in the xe2 provide some AF speed advantage in good light?...  Won't matter to me, I have an X-T1 on the way for better performance, if it even offers much of an improvement over the xe2. It's seems to claim better frame rates while tracking a moving subject at least.
I have enough DSLRs that stand a better chance of catching things that move using their more sophisticated AF systems but I have nothing that's truly fast any more.  7D used to hold that position but I sold it.

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