Canon may be expensive but...

[J.R.]

Yeay yeah no answer, which I could expect from you

have you noticed one thing, Neuro is quiet, with thoughtfulness , little bit of thinking he probably understands now he is wrong, how about you?

Sometimes no answer is the best answer. I could enter into another debate of "facts" but for what point and purpose? To be at the receiving end of more insults from you? No thank you!

Please continue living in your la la land of HTP and cutting the photons in half. In the meantime, I'll do something useful.

 

[J.R.]

no Im saying by exposure after 400 iso you have create a head room by 2 stops compare to 100iso
what is so difficult to understand Neuro! = exposure after 400 iso = halving the hitting lights twice compare to 100iso

Hypothetical example: I shoot jpg. I am taking a picture of a forest scene. I am in Av mode, and I set f/8 to obtain the desired DoF, and I chose ISO 400 to get a 1/100 s shutter speed at metered exposure to avoid camera shake, because I foolishly left my tripod at home. Please note, I couldn't care less about what exposure settings would be at ISO 100, 50, or 3200, that's tangential and irrelevant - I choose f/8 and ISO 400 for the reasons I stated. I take a shot, look at the review image, and see blinking highlight alerts where I want detail of the sun-dappled forest floor. I've read that HTP can preserve my highlights.

If that scenario is confusing, I'll summarize - with HTP off, I set the camera in Av mode, f/8, ISO 400, and the metered exposure gave a 1/100 s shutter speed.

Answer these questions about what happens when I set HTP to Enable:

1) Does my selected aperture of f/8 change?
2) Does the camera-selected shutter speed of 1/100 s change?
3) Does the amount of light hitting the sensor change?

Please, no hand-waving, no 'please read my earlier posts', no repeating what you've posted before, no referring to what may happen at some other ISO setting that I didn't select and don't care about - just answer those three, simple questions with a yes or a no.

You're tough as nails brother ... but I know a lost cause when I see one. All the very best

 

[BrettS]

no Im saying by exposure after 400 iso you have create a head room by 2 stops compare to 100iso
what is so difficult to understand Neuro! = exposure after 400 iso = halving the hitting lights twice compare to 100iso

Hypothetical example: I shoot jpg. I am taking a picture of a forest scene. I am in Av mode, and I set f/8 to obtain the desired DoF, and I chose ISO 400 to get a 1/100 s shutter speed at metered exposure to avoid camera shake, because I foolishly left my tripod at home. Please note, I couldn't care less about what exposure settings would be at ISO 100, 50, or 3200, that's tangential and irrelevant - I choose f/8 and ISO 400 for the reasons I stated. I take a shot, look at the review image, and see blinking highlight alerts where I want detail of the sun-dappled forest floor. I've read that HTP can preserve my highlights.

If that scenario is confusing, I'll summarize - with HTP off, I set the camera in Av mode, f/8, ISO 400, and the metered exposure gave a 1/100 s shutter speed.

Answer these questions about what happens when I set HTP to Enable:

1) Does my selected aperture of f/8 change?
2) Does the camera-selected shutter speed of 1/100 s change?
3) Does the amount of light hitting the sensor change?

Please, no hand-waving, no 'please read my earlier posts', no repeating what you've posted before, no referring to what may happen at some other ISO setting that I didn't select and don't care about - just answer those three, simple questions with a yes or a no.

You're tough as nails brother ... but I know a lost cause when I see one. All the very best

+1 J.R.

The guy's not looking for a discussion, he's only looking to be right.

 

[babiesphotos.ca]

no Im saying by exposure after 400 iso you have create a head room by 2 stops compare to 100iso
what is so difficult to understand Neuro! = exposure after 400 iso = halving the hitting lights twice compare to 100iso

Hypothetical example: I shoot jpg. I am taking a picture of a forest scene. I am in Av mode, and I set f/8 to obtain the desired DoF, and I chose ISO 400 to get a 1/100 s shutter speed at metered exposure to avoid camera shake, because I foolishly left my tripod at home. Please note, I couldn't care less about what exposure settings would be at ISO 100, 50, or 3200, that's tangential and irrelevant - I choose f/8 and ISO 400 for the reasons I stated. I take a shot, look at the review image, and see blinking highlight alerts where I want detail of the sun-dappled forest floor. I've read that HTP can preserve my highlights.

If that scenario is confusing, I'll summarize - with HTP off, I set the camera in Av mode, f/8, ISO 400, and the metered exposure gave a 1/100 s shutter speed.

Answer these questions about what happens when I set HTP to Enable:

1) Does my selected aperture of f/8 change?
2) Does the camera-selected shutter speed of 1/100 s change?
3) Does the amount of light hitting the sensor change?

Please, no hand-waving, no 'please read my earlier posts', no repeating what you've posted before, no referring to what may happen at some other ISO setting that I didn't select and don't care about - just answer those three, simple questions with a yes or a no.

You're tough as nails brother ... but I know a lost cause when I see one. All the very best

+1 J.R.

The guy's not looking for a discussion, he's only looking to be right.

+1 BrettS

 

[Loswr]

have you noticed one thing, Mikael is quiet, with thoughtfulness , little bit of thinking he probably understands now he is wrong

 

[J.R.]

have you noticed one thing, Mikael is quiet, with thoughtfulness , little bit of thinking he probably understands now he is wrong

Hahaha ... Thanks Neuro ... I may be able to sleep tonight after all ;D

But what's to stop him from making a comeback with the familiar - "you do not understand" / "you have no clue" BS?

 

[Loswr]

But what's to stop him from making a comeback with the familiar - "you do not understand" / "you have no clue" BS?

That would indicate to me that he found those three yes/no questions too difficult to answer… :

 

[BrettS]

have you noticed one thing, Mikael is quiet, with thoughtfulness , little bit of thinking he probably understands now he is wrong

OMFG!

I'll forward you my doctor's bill, Neuro. I think I broke a rib laughing...

 

[RMC33]

Yeay yeah no answer, which I could expect from you

have you noticed one thing, Neuro is quiet, with thoughtfulness , little bit of thinking he probably understands now he is wrong, how about you?

Sometimes no answer is the best answer. I could enter into another debate of "facts" but for what point and purpose? To be at the receiving end of more insults from you? No thank you!

Please continue living in your la la land of HTP and cutting the photons in half. In the meantime, I'll do something useful.

Cutting photons.. OH MY SIDES!

 

[RMC33]

halving the amount of hitting photons.
any one still laughing

so here ist the questions again
we start from the beginning so all can understand , and strait answers please
NEURO, HTP at base iso (100iso ) what is that ? how does it work? how do you get it?

and to all laughing people here is where the all started http://www.canonrumors.com/forum/index.php?topic=12437.30
read NEUROS answer.He didn't have a clue how HTP works at 100iso , head-room, natural head -room at 200iso, 400iso etc, AND from 100iso HTP the amount of hitting /striking photons are halved compare too 100iso with out HTP

Still laughing. Don't care.

 

[dave]

Five pages back I was embarrassed for starting this thread, now I'm mortified.

I'd try and contribute but I honestly don't follow most of it.

 

[Loswr]

no Im saying by exposure after 400 iso you have create a head room by 2 stops compare to 100iso
what is so difficult to understand Neuro! = exposure after 400 iso = halving the hitting lights twice compare to 100iso

Hypothetical example: I shoot jpg. I am taking a picture of a forest scene. I am in Av mode, and I set f/8 to obtain the desired DoF, and I chose ISO 400 to get a 1/100 s shutter speed at metered exposure to avoid camera shake, because I foolishly left my tripod at home. Please note, I couldn't care less about what exposure settings would be at ISO 100, 50, or 3200, that's tangential and irrelevant - I choose f/8 and ISO 400 for the reasons I stated. I take a shot, look at the review image, and see blinking highlight alerts where I want detail of the sun-dappled forest floor. I've read that HTP can preserve my highlights.

If that scenario is confusing, I'll summarize - with HTP off, I set the camera in Av mode, f/8, ISO 400, and the metered exposure gave a 1/100 s shutter speed.

Answer these questions about what happens when I set HTP to Enable:

1) Does my selected aperture of f/8 change?
2) Does the camera-selected shutter speed of 1/100 s change?
3) Does the amount of light hitting the sensor change?

Please, no hand-waving, no 'please read my earlier posts', no repeating what you've posted before, no referring to what may happen at some other ISO setting that I didn't select and don't care about - just answer those three, simple questions with a yes or a no.

Answer : yes

Sorry, Mikael - it was a pass/fail test, and you have failed. The answer to all three of those questions is "no". In Av mode, f/8, ISO 400, enabling HTP does not change aperture or shutter speed, and therefore the amount of light hitting the sensor does not change. If anyone believes there a chance Mikael is right, feel free to set Av, f/8, ISO 400 then enable HTP and see if shutter speed or aperture change as a result.

Back in the other thread, I had come to the conclusion that this was semantics and your inappropriate extrapolation of what happens in the special case of ISO 100 in an autoexposure mode to a general explanation of how HTP works.

But...the fact that you answered "yes" to the above questions clearly demonstrates that you do not understand how HTP really works. Despite repeated attempts by several people, including TheSuede, to provide an explanation which you could understand, you fail to grasp some details of the concept. At this point, the only logical conclusion is that you are simply incapable of understanding the mechanism of HTP. Not due to language, semantics, etc. - just a fundamental inability to comprehend this concept. You are wrong, you don't get it, and apparently you never will, much less admit that you're wrong and/or incapable of understanding the concepts.

To paraphrase an earlier statement of yours, it's impossible to discuss this with someone who does not understand the basics - and that someone is you, Mikael. For my part, this discussion is done. Any further statements or questions from you on this matter will be ignored.

 

[LetTheRightLensIn]

Their 800mm lens isn't $18000.


http://www.thedigitalpicture.com/News/News-Post.aspx?News=4073

And that is why Canon is discontinuing the current one for a Mark II soon....

 

[LetTheRightLensIn]

By all means, people should read that thread and observe Mikael 'Half The Photons' Residal's staunch defense of his explanation that the general mechanism of HTP is that the camera reduces by half the amount of light hitting the sensor, his consistent refusal to admit that his 'explanation' applies only at ISO 100, his avoidance of specific questions from several posters to describe how HTP works at any other ISO setting than 100, etc. Note how here in this thread, he reposts TheSuede's correct description of how HTP works, which matches what others in the thread were saying, but not his own flawed and incorrect explanation.

Doesn't it sort of halve the collected photons though, depending upon how you go about talking about it? If you set ISO400 HTP it uses ISO200 but exposes as if you were using ISO400 so you are shooting ISO200 but as if you were ISO400 so the camera metering does toss away a stop of light compared to what it does when you shoot ISO200 as 200 instead of 200 as ISO400 HTP. So, using the proposed tone curve, it shifts the middle gray and everything else down a full stop so you have 1 stop more room for highlights.

If you compare ISO400 to ISO400 HTP they expose the same way and collect same # of photons but the one without HTP applies one stop more gain than the other and assumes a more typical tone curve will be applied and doesn't shift all of that down 1 stop. But looking at it from the true RAW level ISO400 HTP actual corresponds to ISO200 not ISO400....

It depends how you go about talking about it in detail. I don't know if talk about photon collection is really is the best way. I didn't read that other thread of much of this yet so I don't know went on.

I think it is simplest just to say that:

1. HTP isn't anything special and isn't a real new mode and it is nothing more than software and metering games.

2. You can do the exact same thing (for RAW shots) by using ISO stop lower in regular mode than what you set in HTP mode and then setting EC -1 to all your shots (or for M mode decide simply use the ISO you want in either case and then for the times you want the 'HTP' shots you decide to set shutter speed one stop faster so as to save one stop more highlights)*.

3. All HTP is is metering at the labelled stop but applying the gain of one stop less and, in cam (or default in RAW converters), applying a special tone curve that shifts most of the data down one stop and applies different tail and especially top end curves.



*And then you shift things around with the RAW settings to give it a curve a mid-tone point that works (using some built-in profiles you may run into the twisted profiles issue and if you are not skilled at moving sliders and setting TRCs and such it might be a bit trickier with some software to work it out as well than having the software give you automatic starting point under the hood though perhaps, although since most standard starting points and exposures are not fully ETTR you might not actually hit all that must problems at all and might even hit less).

That's all you had to say, Mikael. Why did you feel in necessary instead to lead off by insulting my knowledge and intelligence?

I'm just guessing, but maybe he was just snapping after all the grief dumped on him in some other threads and stuck in fight fire with fire mode after all of that? Jrista and plenty others certainly insulted him by the bucket load (myself too in some of those threads ;D :'( :'( :'(). Some people who were rather incorrect about a lot of things had been dumping all sorts of insults over a few members for a long time, maybe he just got sick of it and now just snaps back at the slightest hint of anything? Maybe not the best way to go about it, but you can understand a bit where it comes from (plus it is interesting that none of those bashing him now ever got on the cases of everyone who started insulting him and others way back when and they were all fine with it all in that case, why, probably because the ones insulting and bashing in those cases tended to rarely ever treat Canon as anything less than a god.).

 

[LetTheRightLensIn]

Of course, headroom is needed to preserve the highlights. We agreed on the 'what' - your error concerned the 'how'. My point was that HTP achieves the additional headroom by exposing at a one-stop lower ISO than is actually selected, not by reducing the exposure so that 'half the photons' hit the sensor as you repeatedly stated.

Isn't is basically just semantics?

And from a RAW RAW perspective what is using an ISO as if it were one ISO stop higher but exposing that ISO by one less stop? From that perspective it is collecting half the photons. If we try to do what HTP does ourselves without using it, which we can do because it is not a special mode, then what do we do? We keep using the same ISO we were just using and then make the shutter speed 1 stop quicker = the whole less photos collected scenario. What really is going is a simply a collecting less photons thing.

If you look at from the perspective of does ISO400 HTP collect any less photons (going by autometering) than ISO400, then no it doesn't it is just applying less gain, but then if it is applying less gain it is NOT really ISO400 any more is it so you might say the early way of looking at it is the more natural way?

Both perspectives can be said to be correct but I actually think Mike's seems a bit more the natural way to think about it although I suppose one can argue back and forth about what one considers natural.

 

[LetTheRightLensIn]

I felt cheated on learning that Canon publishes hypothetical MFT charts and does not actually test a sample lens.

Would you feel any less cheated if your shh copy didn't come close to their best of 50 that they used for the real test though? ;D

Although it would make f/2.8 vs f/8 performance clearer (since diffraction would be hurting f/8 performance real world) and some designs as I believe Leica once insinuated referring to Canon may be easy enough to make perform in a simulator with every lens carved and placed perfectly and yet an utter bear to produce on a real world manufacturing line where for some tricky designs 99.9% of lenses coming out may have nothing to do with the calculated charts at all. It might make them tune more for real world reasonably consistently produceable designs more??? But they probably do what they do anyway.

 

[LetTheRightLensIn]

My problem with you [Michael] arose at the time of the "Half The Photons" discussion where, from your [Michael's] posts I got the impression that changing the ISO would somehow change the photons hitting the sensor. I'm sure you knew fully well that changing the ISO does not change the number of photons hitting the sensor then why the charade? What's the point of your expertise if you ultimately end up confusing people - Well you may very well say I'm a noob but there are a number of noobs on CR who log on only to look for some help?

Because is not just changing the camera back to ISO200. It keeps metering at ISO400 while changing the camera gain to ISO200. And if you meter at ISO400 you are getting less exposure than you would metering at ISO200 which the camera is actually working at. If anything, I think looking at it from his point of view seems less misleading. Effectively it is just an automatic and hidden EC -1 to the shutter speed, that is how you'd replicate it yourself in RAW without using the mode, with an automatic tone curve (applied in cam, and suggested to the RAW converter) making the JPGS and histograms look like EC0 with more highlights instead of a flat EC -1 across the board. How do you replicate ISO400 HTP in say Av mode for RAWs? You shoot ISO200 Av mode with EC -1.

 

[LetTheRightLensIn]

This does not automatically happen in M or B! Do you not agree? I agree that your statement would be true for P, Av, Tv and the Green Rectangle... Your statement is a generalization. However, it cant be true for all the settings on my 5D3.

But if you shoot a RAW at ISO400 HTP mode at say 1/60th and f/2.8 and looked at the linear RAW file histogram it would look like an ISO200 HTP-off 1/125th and f/2.8 taken image and not an ISO200 HTP-off 1/60th and f/2.8 image.

Or more aptly, if you look at the blinky suggested metering line shown to you in M or B mode it would act just as you say it will for P, Av,Tv,etc.

 

[LetTheRightLensIn]

no Im saying by exposure after 400 iso you have create a head room by 2 stops compare to 100iso
what is so difficult to understand Neuro! = exposure after 400 iso = halving the hitting lights twice compare to 100iso

Hypothetical example: I shoot jpg. I am taking a picture of a forest scene. I am in Av mode, and I set f/8 to obtain the desired DoF, and I chose ISO 400 to get a 1/100 s shutter speed at metered exposure to avoid camera shake, because I foolishly left my tripod at home. Please note, I couldn't care less about what exposure settings would be at ISO 100, 50, or 3200, that's tangential and irrelevant - I choose f/8 and ISO 400 for the reasons I stated. I take a shot, look at the review image, and see blinking highlight alerts where I want detail of the sun-dappled forest floor. I've read that HTP can preserve my highlights.

If that scenario is confusing, I'll summarize - with HTP off, I set the camera in Av mode, f/8, ISO 400, and the metered exposure gave a 1/100 s shutter speed.

Answer these questions about what happens when I set HTP to Enable:

1) Does my selected aperture of f/8 change?
2) Does the camera-selected shutter speed of 1/100 s change?
3) Does the amount of light hitting the sensor change?

Please, no hand-waving, no 'please read my earlier posts', no repeating what you've posted before, no referring to what may happen at some other ISO setting that I didn't select and don't care about - just answer those three, simple questions with a yes or a no.

1,2,3,
no, no, no

BUT you forget that when you hit the HTP button you are no longer at ISO400 any more but you are at ISO200 only the camera is still metering at as if it were at ISO400. You are not getting to the point of what HTP really is, it is NOT some magic hardware where a new set of photosensors are enabled to capture extra highlights or something, it isn't a 'real' mode, if you want to replicate the mode yourself you can even with a camera that has no HTP button. If you want HTPISO400 and were shooting scenes at say EC0 then you just use ISO200, lock your aperture and then EC -1 or roll up the shutter speed yourself, if in M mode say, 1 stop.

What the camera is actually really doing is just exposing 1 stop less, collecting less photons for any given auto-metering or placement of suggested metering mark.

I can see where your way of looking at it comes from too, but I think it kinda is a less natural perspective.

It doesn't really matter what the camera labels and calls things but what matters in the end is what the sensor is doing, what the shutter speed is, what you get in the RAW file. I think it makes more sense to look at it from if I want to do HTP myself what do I need to do? To get the exact same result I shoot at my selected ISO, keep my selected aperture and then I raise the shutter speed 1 stop faster.

 

[rpt]

This does not automatically happen in M or B! Do you not agree? I agree that your statement would be true for P, Av, Tv and the Green Rectangle... Your statement is a generalization. However, it cant be true for all the settings on my 5D3.

But if you shoot a RAW at ISO400 HTP mode at say 1/60th and f/2.8 and looked at the linear RAW file histogram it would look like an ISO200 HTP-off 1/125th and f/2.8 taken image and not an ISO200 HTP-off 1/60th and f/2.8 image.

Or more aptly, if you look at the blinky suggested metering line shown to you in M or B mode it would act just as you say it will for P, Av,Tv,etc.

I think you need to read that part again. That was not about HTP. That was before HTP sucked up this thread too...