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Messages - raptor3x

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31
EOS Bodies / Re: Just for Jrista: 2014 Market Data
« on: September 24, 2014, 09:17:40 PM »
"I'm sorry; not seeing any color noise, posterization, and banding. Not really seeing much of a noise cost at all to shooting ISO 100."

I think we should all be able to agree that there is also no color noise, posterization, or banding in my "real world" 100% crop as well, though that does only have an approximately three+ stop lift.

To see the banding you have to lift shadows ridiculous amounts, 6+ stops.  The posterization though can be seen in histograms relatively early on though but only really becomes a problem when, again, making silly shadow lifts.  The color noise surprises me though, as this is something I see when lifting ~4 stops or so.   Maybe an A7 vs A7R thing.

Ok, keep in mind that at 6+ stops you need to expect noise levels of ISO 6400 and above. C'mon. Let's be reasonable.

And yes, more than 5 stops of pushing and you might see some effects of downstream read noise or quantization error, compared to the ISO 6400 or higher (not pushed) shot.

And, yes, different sensors will perform slightly differently here. I believe the A7 is a slightly older sensor, but it shouldn't be accounting for the drastic differences in your experience vs. what I just showed above.

A 6+ stop push is where I'm most interested because most of my shooting is above ISO 3200.  Once you get to this point the midtones look noticeably worse for an ISO 100 shot pushed up than a native high ISO shot; this is the issue I have with the claim that you keep all the dynamic range.  You can keep the highlights but the shadows and midtones turn to garbage.  The reason I mentioned the histogram is because while you can't really see the posterization at ISO 1600 in the image, you can see it in the histogram already and it becomes visible in the pictures once you start trying this same technique at even higher ISO values.

32
EOS Bodies / Re: Just for Jrista: 2014 Market Data
« on: September 24, 2014, 08:42:03 PM »
"I'm sorry; not seeing any color noise, posterization, and banding. Not really seeing much of a noise cost at all to shooting ISO 100."

I think we should all be able to agree that there is also no color noise, posterization, or banding in my "real world" 100% crop as well, though that does only have an approximately three+ stop lift.

To see the banding you have to lift shadows ridiculous amounts, 6+ stops.  The posterization though can be seen in histograms relatively early on though but only really becomes a problem when, again, making silly shadow lifts.  The color noise surprises me though, as this is something I see when lifting ~4 stops or so.   Maybe an A7 vs A7R thing.

33
EOS Bodies / Re: Just for Jrista: 2014 Market Data
« on: September 24, 2014, 08:14:43 PM »

And some people wonder why I try to make it a point to dispel these fallacies?

P.S. Yes I know the ISO 100 shot could've been processed better, but I only spent 30s processing just to try & waste as little time as possible with this. Window lighting is pretty challenging and requires proper use of masks in PS if you want to do it right. Doesn't change my point.

Not all of the issues will show up the moment you try to do this for ISO 1600, although even in your own example I can already see shadow areas that have a significant magenta cast compared to the ISO 1600 version.  Additionally, I can almost guarantee that if you post the histogram for the ISO 100 image you'll already see the signature of posterization in the shadows.  Once you get up to ~6400 though you end up with very nice highlights and garbage midtones and shadows.  This was an idea I was quite excited about when the A7R first came out, but in practice it's just not that useful.

34
EOS Bodies / Re: Just for Jrista: 2014 Market Data
« on: September 24, 2014, 02:44:29 PM »
*And yet shooting at ISO 1600 - which deprives the sensor of 4 stops of light compared to ISO 100 in the traditional sense - is OK... hmm perhaps zlatko didn't understand that changing the ISO setting on your camera doesn't actually change the native sensitivity of the sensor. All it does is amplify the data. Well, me raising the exposure +4 stops is 'amplifying the data' - just at a different step of signal processing. Why is one valid and the other not? And that's the point - it *is* valid for Nikon/Exmor, just not for Canon, where you have to amplify early on. So this requires a shift in thinking, and it doesn't change my point: being able to amplify later is advantageous b/c it gives you stops and stops of highlight headroom, essentially giving you the full DR of the sensor at higher ISOs (there are limitations at extremely high ISOs, but I won't go into that here).

I thought this was what you were getting at.  This was literally one of the first things I tried when I first bought an A7R and unfortunately, this is not very useful at all.  Because middle grey will be buried so deep within the shadows, color noise, posterization, and horizontal banding (yes, Exmor has banding noise as well if you dig deep enough) all become major issues.  Even when emulating ISO 1600.

35
Lenses / Re: DXOMark Reviews Zeiss Otus 85mm f/1.4
« on: September 24, 2014, 10:35:33 AM »
I find it really interesting that the lens has, apparently, 1/3rd stop less vignetting on the D800 than the 5D3.

36
EOS Bodies / Re: Am I the only one excited about the new 7D mk2?
« on: September 23, 2014, 07:27:50 PM »
They're measuring the DR at ISO 6400 to be equal to the 5D3.

No, it's less.
It is better than for the 7D though, but about half a stop (maybe +/- 1/3 stop as the masked vs main area and high ISO ratings might differ).

The dynamic range of both the 7D2 and 5D3 at ISO 6400 is 8.3EV based on the measurements from the sample RAWs for the 7D2 and DXO for the 5D3.

It remains to be seen. I measured higher for 5D3 and even 5D2, but I didn't apply actual ISO rating correction for the 5D3 as DxO did. Their 5D3 copy also might be a little bit on the weak side for high ISO read noise compared the two I've tested.

I find this really interesting.  Do you think this is due to copy variation or due to a difference in the way the tests are conducted?  Do you see differences in high ISO DR for short exposures in bright light vs longer exposures in dim light?

37
EOS Bodies / Re: Am I the only one excited about the new 7D mk2?
« on: September 23, 2014, 09:14:35 AM »
They're measuring the DR at ISO 6400 to be equal to the 5D3.

No, it's less.
It is better than for the 7D though, but about half a stop (maybe +/- 1/3 stop as the masked vs main area and high ISO ratings might differ).

The dynamic range of both the 7D2 and 5D3 at ISO 6400 is 8.3EV based on the measurements from the sample RAWs for the 7D2 and DXO for the 5D3.

38
EOS Bodies / Re: 39-46MP 1DsX in Oct????
« on: September 22, 2014, 10:11:48 PM »
Then again, having just looked at the rumor starter's personal website for the first time....
suddenly I now rank this a CR -10000000000.

Yeah, saw that as well.  :-\

39
EOS Bodies / Re: Am I the only one excited about the new 7D mk2?
« on: September 22, 2014, 10:02:56 PM »
Yeah, the AF system is probably the most important feature for the 7D II. Frame rate is probably next important, and they did well there. I personally was looking at the sensor to see if Canon had moved to a new fab, and it does not appear they have. That's disappointing to me, just in what it indicates for the future (which could change, but I'm skeptical.) I am very curious to see how the Samsung NX1 performs in real life. If it has Canon lens adapters, it might be a very viable competitor, given it's high FPS. The AF system sounds awesome...if it is as awesome as it sounds...I might actually pick one of them up (in part also for astrophotography...a high res BSI APS-C would be pretty awesome for OSC AP.)

I also just saw the Canon page on the updated information they are now displaying in the viewfinder, which is pretty cool. I don't see a histogram in there yet, which is sad, but Canon seems to be moving in that direction with it.

I concur that the AF and frame rate (and the buffer to use the frame rate!) are the key elements.  A new "knock your socks off" sensor would have been cool too, but it was less of a priority for me than the AF, FPS and buffer.  "Decent" IQ with a killer AF/FPS and buffer was more important than a great new sensor and a disappointing AF/FPS and buffer. But getting both would have been awesome of course.  I think we'll have to wait for the next FF camera to see what else Canon has up their sleeves for sensor tech.

If, once tested, the 7D II hits with around 35,000e- FWC, I'll be more impressed. That would be a fairly significant improvement, meaning dynamic range really did improve. It would still be half (at best) what you get out of a full frame, but, it would be enough to really improve IQ at high ISO. ISO 16,000 could have a decent amount of DR and color fidelity with such a charge capacity. I suspect it'll be somewhere around 26-27ke-, which is about the same as the 70D...but if it tops 30-35k, that would be pretty nice.

Somebody over on FM dug through the sample RAWs and it appears that while the low ISO DR hasn't improved much, the high ISO DR has improved very signficantly.  They're measuring the DR at ISO 6400 to be equal to the 5D3.

40
Increase minimum shutter speed for Av mode to at least 1/2000 like the 1DX.  Preferably just copy the 7D2's Auto ISO behavior.

41
Reviews / Re: Tony Northrup - D810 vs. 5D Mk3
« on: September 20, 2014, 09:50:09 AM »
Oh, and yes: it's unfortunate the A7 seems perform worse than the A7R at high ISO (~1/3 EV worse?). Not sure what happened there. Lower effective QE b/c of on-sensor PDAF? If this weren't the case, the A7 would probably be the better camera b/c it has on-sensor PDAF that helps it track (noticeably better than the A7S/R, which just hunt back and forth while trying to track, potentially leading to completely OOF images in AF-C), and EFC which means you can actually use it with telephoto lenses.

In terms of SNR I think the difference between the two is quite small, but something about the quality of the A7 noise doesn't respond well to LR's noise reduction and so in practice the difference is at least a full stop, if not more.

Also, any more detail on how you can get close to base ISO DR when using high ISO on the D810?

42
Reviews / Re: Tony Northrup - D810 vs. 5D Mk3
« on: September 19, 2014, 11:59:29 PM »

I can't speak specifically to the A7. I haven't edited any of it's files. I guess I assumed the A7 had similar quality to the A7s, which doesn't seem to be that bad. I'm not surprised, though. The A7 was the first of the A7 line, and I think Sony rushed it a bit. Hopefully they will get better with successive models...and hopefully, they will stop compressing the raws with a lossy algorithm. :P

I think it has to be something like that.  I bought an A7R when it was first released and the high ISO was surprisingly good when downsampled.  I was really surprised at how bad the A7 is at high ISO when I got mine, I expected it to be even better but that's not the case at all. Either that or I've got a bum copy.

43
Reviews / Re: Tony Northrup - D810 vs. 5D Mk3
« on: September 19, 2014, 11:50:49 PM »
I also wouldn't say Canon "trounces" anything at high ISO. High ISO is primarily limited by physics. Canon has a marginal benefit at high ISO vs. cameras that are now becoming "last" generation, like the D800. The Nikon D810 closes the gap with the 5D III a bit more, and starts to encroach on 1D X territory at really high ISO (I actually think the D810 offers more DR at ultra high ISO than the 5D III...on a normalized basis, the D810 gets 7.7 stops of DR at ISO 51200 to the 5D III's 5.7 stops).

The A7 has quite a nasty quality to the noise at high ISO.  I've had both an A7 and A7R as well as the 5D3 and while from a SNR ratio aspect I'd suspect there's not a huge difference, the A7 has a very poor quality to the noise that doesn't clean up with NR very well at all.  In practice I'd put the 5D3 ~1 2/3 stops ahead of the A7 and the A7R ~1- 1 1/3 stops ahead.

The only thing out there right now that is really "trouncing" any other camera at high ISO is the A7s. It actually enjoys a two-stop advantage over the 1D X at ISO 51200, bringing nearly 9 stops (8.8 to be exact) of DR at that level. At lower ISO's it actually normalizes out a bit with the 1D X...the A7s' true advantage is at the ultra high ISO settings, and it does a remarkably good job.

The A7S is certainly a very intersting camera.  I was really hoping that the D750 was going to be a D810 with the A7S sensor inside.  If they had done that I probably would have picked one up along with a 70-200VRII.  As for the D810 at 51200, I'm not sure which numbers you're looking at but I see it about equal to the 5D3 and ~2/3rd stop behind the 6D in dynamic range for the normalized print size on DXO.

44
Reviews / Re: Tony Northrup - D810 vs. 5D Mk3
« on: September 19, 2014, 10:26:18 PM »
If you're going to complain about apples to oranges, at least compare Canon's best against Nikon's best.  At pixel level, the D810 has a 1.9EV advantage over the 6D and a 2.2 stop advantage when both are downsampled to 8MP.  The 6D has a 1 stop advantage at ISOs over 800 at a pixel level and 2/3 stop advantage when downsampled to 8MP.

OK, that's fair.

The D810 still has higher DR at higher ISOs if you use your camera in a smarter way though, so those DxO higher ISO DR values are meaningless to me.

Can you explain this further?  I shoot an A7 as well as Canon and in my experience the Canon trounces the A7 at high ISO.

45
Reviews / Re: Tony Northrup - D810 vs. 5D Mk3
« on: September 19, 2014, 09:37:30 PM »
If you're going to complain about apples to oranges, at least compare Canon's best against Nikon's best.  At pixel level, the D810 has a 1.9EV advantage over the 6D and a 2.2 stop advantage when both are downsampled to 8MP.  The 6D has a 1 stop advantage at ISOs over 800 at a pixel level and 2/3 stop advantage when downsampled to 8MP.

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