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03-14-2016, 09:57 PM   #211
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QuoteOriginally posted by jsherman999 Quote
They most certainly are.

Look, if you're just interested in a back-forth insult fest with me, I'm game I can literally keep going until the thread is closed. (Bad habit of mine, I'll admit - i can't leave that fish in the barrel alone, even after it's been shot.)

But if you're not - if you really have specific objections to Equivalence, just state them sans-smugness and maybe we can help you out. Or check any of the dozens of citations out there. I gave you one earlier where dosdan bothered to provide links and quotes from Emeril Martinic, and if you really try you can glean from that alone how the 'screen tab' is not meant to be your camera-buying metric.

Actually reading the link = brain++;

"...First off, look at the SNR (18%) ("Print" tab). This is a proxy for Quantum Efficiency & Fill Factor. As you can see, both FF cameras are about 4db (1.3 stops) better than the APS-C when the overall sensor output is considered. This is due the the 2.34x larger FF sensor compared to APS-C. If we switch to the "Screen" tab, where the effect of sensel size is considered, rather than the total output performance, we see that both 4.75m sensels perform much the same, while the bigger 5.9m performs better.
"


Ooh, gotcha.


You wait long enough and an ideologue can't help themselves ... they say too much.


The print tab is not a proxy for Quantum Efficiency and Fill Factor at all, or Total Light, or whatever you imagine.


@Dosdan actually does not understand it, but he said what you wanted to believe and you trusted him instead of what I've written. Such is the problem with confirmation bias.


It has nothing to do with sensor size, just numbers of pixels.


I suggest for a second (and final) time that you go to the DXO Mark site and see for yourself - otherwise you can't explain why the Pentax K-50 does better in the Normalization step than the Sony A7S, and the APS-C Pentax K-3 does equally well as the FF Nikon D750.


Last edited by clackers; 03-14-2016 at 10:09 PM.
03-14-2016, 09:58 PM   #212
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QuoteOriginally posted by Ian Stuart Forsyth Quote
How so

If I was to use porta 160nc 135mm film in my 35mm camera and I take an image using my 6x6 with porta 400nc shoot the same landscape at the same DOF,SS and FOV (shot at equivalency )we would find that they would appear to contain the same level of noise when printed at the same 8x10 print. That sound more like proof of equivalency than not



IF you don't believe my then why not have a look at what Kodak says http://www.kodak.com/global/en/professional/support/techPubs/e58/e58.pdf

with regarded to grain pattern you will see that a 4x6 print from a portra 135 160nc has print grain of 30 and a 4x6 print for portra 120/220 400nc has almost the same print grain at 29

who would have ever thought this was possible.



Now I already know what you are going to say well they are using different emulsion between those 2 films, well you are right they have to each film was exposed to different densities of light so you use different emulsions, same as having to shoot at iso 225 for FF and iso 100 for cropped because of the lower density of light hitting the larger sensor. Now I know you will respond bla bla this and that or can we just jump to the insults as witnessed before.



Its funny that you should sidetrack this discussion about the E word from digital to film as Eric has already provided evidence and the underlining physics to the E word. Something you have yet to understand.

LOLWUT?!! If you were to apply equivalence fu between your 135 and 6x6 Portra then you will have to underexpose your 6x6 by probably more than 5 stops and push by 5 stops in the lab and you expect it to produce the same output quality as the properly exposed 135 film?!!! You are dreaming. Try it lol!!!

We know that the above will crash and burn for the 6x6 that's why 135 and 6x6 film are EXPOSED and DEVELOPED in EXACTLY the SAME formula. And they will result in EXACTLY the SAME GRAIN (i.e. noise) regardless of film size. Your film is the equivalent of DXOMark's SCREEN SNR. The story changes though when you start enlarging the films. Of course 6x6 will win due to size and that is the equivalent of dxomark's PRINT SNR normalised as if the film was printed at 8x10.

So, no, equivalence is very wrong.
03-14-2016, 10:13 PM   #213
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I'm waiting on @Parallax to pop in here and calm people down.
03-14-2016, 10:33 PM - 2 Likes   #214
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I'll chime in.
Lots of information (that's great) but too much emotion (that's not so great).
Please take a break from this thread for a day then come back with less adrenaline +/- testosterone on board...

03-17-2016, 03:30 AM   #215
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QuoteOriginally posted by monochrome Quote
This is why I never go to DPR. Take it somewhere else.
I don't know this forum design well enough to know ho you are replying to but it may not much matter.

This all seems like some play based on Gulliver's Travels. Reading arguments made by little-enders, I wonder why they use APS-C... if there is no benefit to FF, surely using 4/3 is no penalty. They could just as well spend time on an Olympus board arguing APS-C offers no advantage..

Looking through many of posts, I am fascinated in the same way I was when I first approached Omaha, Nebraska from the south. On the bluff overlooking the river, are two train engines on the same track and facing each other. There are displayed to advertise some railroad museum, but the the message I got from looking at the two trains meeting was surely not intended by the people that placed them..?

No longer in Kansas.. we are entering Omaha.
03-17-2016, 05:41 AM - 1 Like   #216
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I don't see too many arguing there is no benefit at all to FF. It may not offer a significant advantage for every use, and for many, the benefits may not outweigh the costs and trade-offs. I use everything from 1/1.6 to FF and even 6x7 film, but I use APS-C the most. Perhaps I would be just as happy in some cases with M4/3 or 1", but we all have to make decisions about how much we will spend and how many formats and brands we want to deal with. I don't take the positions people take here as saying any format is useless.
03-17-2016, 06:35 AM - 1 Like   #217
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Hmm, regarding DOF differences, the main advantage I see could be stated differently: I can stop down my lens another stop with the same DOF. There's often a big difference in sharpness and aberrations between f/1.4 and f/2, or f/2.8 and f/4, especially on normal primes. What I could only do with the lens wide open on APS-C, I will now be able to do on FF with the lens performing better stopped down.

I look forward to seeing how my A50/1.2 performs at f/1.8
03-17-2016, 07:09 AM   #218
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I think the hard thing is that if you aren't maximizing APS-C, the odds are you probably don't need full frame. To me, it is folks pushing the extremes -- shooting really high iso a lot, printing really big, or needing really shallow depth of field -- particularly shallow depth of field with wide angles -- who will see benefit from full frame.

I think there are two things to say. First of all, you don't need to create a need for a new camera in order to buy it. You just need to want it and have the money. The second thing is that saying that most folks probably don't need more than APS-C doesn't mean that there aren't advantages to full frame. It is just that you have to be a power user to actually see a lot of benefit.

03-17-2016, 07:16 AM   #219
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Anyone who went through the time ,weight and expense to buy and use a 1.2 lens should be delighted with an FF body.
Folks like me who don't even own a 1.4 lens, not so much. We're I really into that low light thing, I still have a slew of 1.4 lenses to try out before I look at FF, for low light.
03-17-2016, 07:48 AM   #220
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It would be worth doing a dof calculation. There are a bunch of dof calculators on the internet. What you will find is that your f1.2 50mm will have a wider depth of field on the full frame compared to the apsc, in measured terms, but that in the whole image, a narrower band will be in focus on the FF compared to the apsc. Same lens, same distance from focus point.
03-17-2016, 09:18 AM   #221
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DOF does not change, only the angle of view from any particular lens changes. If you take a photo on a FF camera and crop the image to the area covered on a K-3 you will see no difference what-so-ever. To get equivalent results in framing, depth of field etc you will need to go to a wider lens on the K-1. Instead of a 21 on K-3 you will need a 15 on K-1. Instead of a 24 on K-3 you will need a 35 on K-1.
Most people just do not understand the relationship between DOF, aperture, camera to subject distance (perspective),
You can take a 200mm lens on an 8x10 camera, crop a 35mm frame out of it and you will see exactly what you get on 35mm film with a 200mm lens with both cameras positioned in the same place on the same subject, same f stop.
It is so funny to see the worry and confusion from people who have only used a camera with a crop sensor when faced with moving to FF. Anyone who comes from old 35mm film days has no confusion at all.

Last edited by jeverettfine; 03-17-2016 at 12:49 PM.
03-17-2016, 10:05 AM   #222
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The normalization is about the whole image, but the screen s/n is about pixel to pixel comparison.

So the K3 vs the D800e is close to a stop worse at iso 3200. The K5iis is pretty close to the same. Pixel to pixel.

Same lens, same subject distance and cropped to show the same scene would have less pixels on the K1 vs the K3, and the perceived noise would be what?

If I could get the same scene framed into either formats by moving or lens change, the full frame has a substantial improvement.

I am not certain for my shooting, and am trying to work out the difference. I suspect that for some circumstances it would be better, some worse, and more than likely different choices would be made to get the best shot in any circumstance. That is what I'm trying to figure out.

So far, this is what I know.

Depth of field is immaterial. If I get it in focus on my K3, I will have it in focus on the K1. That is my primary concern; no giving up a stop necessary.
At pixel to pixel comparison, the K1 is close to a stop better noise characteristics at higher isos.
The pixel density is lower, about where the K5iis was.

I would like to see a chart similar to the print noise s/n where the calculation has an iso setting, a % grey and % crop from the sensor size for both the K3 and K1. That is what I am interested in. A normalized s/n at various crops.

---------- Post added 03-17-16 at 10:20 AM ----------

Detailed computation of DxOMark Sensor normalization - DxOMark

The formulas they use are there. I have to go do some work to make money to afford this stuff, but intend to try to plot something.
03-17-2016, 11:16 AM   #223
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QuoteOriginally posted by derekkite Quote
The normalization is about the whole image, but the screen s/n is about pixel to pixel comparison.
nobody delivers photos at 100% pixel size, they are always edited and re-sized, so it's not useful for anything.

you can see what the actual noise looks like in the dpr studio scene comparison tool, for both normalized and 100% pixel view... pick the k3ii and a d810, for example.

wrt pq, ff is all about increasing resolution and decreasing noise, by putting all of the available pixels to work for you... if your crop sensor camera is satisfactory there, don't waste money on ff.
03-17-2016, 12:28 PM   #224
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QuoteOriginally posted by osv Quote
nobody delivers photos at 100% pixel size, they are always edited and re-sized, so it's not useful for anything.

you can see what the actual noise looks like in the dpr studio scene comparison tool, for both normalized and 100% pixel view... pick the k3ii and a d810, for example.

wrt pq, ff is all about increasing resolution and decreasing noise, by putting all of the available pixels to work for you... if your crop sensor camera is satisfactory there, don't waste money on ff.
OK, so where do the curves cross? At 100% the d810 is almost a stop better. But resolution matters, so the perceived noise of a higher resolution yet noisier sensor is better normalized, at some point away from 100%. Where?

I'm not talking about some theoretical possibility, this is where I live in my photography. If an apsc body a stop better noise was announced I'd preorder two. I'd seriously look at a 500 f4 for half a stop. I pack around a flash on wet days to get stops, I shoot from a tripod to gain a couple stops.

I and others like me are the reason that they make this stuff because better sensors and the like open shooting opportunities.

The cropped sensor is not satisfactory.
03-17-2016, 12:30 PM - 1 Like   #225
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Isn't it ironic spend years arguing for FF and now it's becoming reality people start arguing that it's not required. I think half you mob on here would argue black and blue. But carry on anyhows.
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