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01-07-2013, 05:44 PM   #16
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QuoteOriginally posted by Ikarus Quote
The other day I discovered that it also does the reverse - stopping it down, if there is too much light. Check it out!
I mentioned that - a number of people have complained about the clicking sound it makes when it does it. I call it 'squinting'.

01-07-2013, 07:05 PM   #17
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this is why I advocate learning on a manual film camera, you should know what your camera is outputting before you hit the shutter. But I think what your looking for is called DoF preview, been used since the film cameras, map DOF preview to the green button and you will get your exact exposure... It's funny the things people complain about when they are so deep into the auto world...
01-07-2013, 08:23 PM   #18
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QuoteOriginally posted by wanderography Quote
this is why I advocate learning on a manual film camera, you should know what your camera is outputting before you hit the shutter. But I think what your looking for is called DoF preview, been used since the film cameras, map DOF preview to the green button and you will get your exact exposure... It's funny the things people complain about when they are so deep into the auto world...
I think you're wrong. The complaint is about the live-view histogram showing 100% irrelevant and misleading information in manual mode at all times. It's not a new problem either.
01-07-2013, 09:49 PM   #19
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QuoteOriginally posted by wanderography Quote
this is why I advocate learning on a manual film camera, you should know what your camera is outputting before you hit the shutter. But I think what your looking for is called DoF preview, been used since the film cameras, map DOF preview to the green button and you will get your exact exposure... It's funny the things people complain about when they are so deep into the auto world...
1. I did learn on a fully manual camera. I also shoot Leica.
2. DoF preview isn't what I mean. Exposure preview means just that - a reflection of the amount of light I'll capture at a given ISO, aperture and shutter speed.
3. The idea that tools which help you measure exposure are signs of lack of ability is false - unless you don't use a light meter and never bracket? My father made all his exposure calculations in his head. It made him slower than me, not better.

02-03-2013, 01:45 PM   #20
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QuoteOriginally posted by Ikarus Quote
I'm with you on this. The histogram display in manual mode is useless at best. In fact, I'd say it is misleading.
The Bright/Dark area highlighting is even worse, since it is not only useless, but incredibly distracting.
02-04-2013, 01:55 PM   #21
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It would be nice to "see what the camera sees," but I don't think it will happen, unless, like you mentioned, we get some custom firmware. It would have to do a DoF preview, but incorporate the exposure as well. If the price on the K-01 wasn't so amazing, I would have a Sony SLT sitting here as the EVF on it is really an amazing revelation. Due to the way the SLT works, you are seeing exactly (to a degree anyway) what the sensor sees. You make an adjustment to the settings and the display adjusts as well. That one feature almost sold me, but I live for tech, so yeah. Then, I looked at the price and dearth of lenses and I stayed with Pentax.
03-12-2013, 09:44 PM   #22
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QuoteOriginally posted by MrSkelter Quote
The lens can remain open but when we set it to F22 the processor can calculate the loss of light and adjust the displays accordingly if desired.
You can only calculate exposure change with stopped down lens, you can't predict histogram... Not to any precise level, at least. You can try estimating the change if you have fixed lens -you can profile it. But if lens can be changed, its impossible, error margin is too wide.
03-13-2013, 08:44 AM   #23
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QuoteOriginally posted by dgcom Quote
You can only calculate exposure change with stopped down lens, you can't predict histogram... Not to any precise level, at least. You can try estimating the change if you have fixed lens -you can profile it. But if lens can be changed, its impossible, error margin is too wide.
The Canon G1 X does it. So do many others. They are fixed lens but I don't see why that's a problem. If the camera makes a guess, it can check that guess against the histogram of the exposed frame once it's been shot. In that way the camera can 'learn' the response of each lens.

That said, even an educated - conservative - guess is better than nothing. All I want is to be able to see if I'm blowing highlights or blocking shadows with some accuracy. If I'm shooting a portrait in front of a window I might be happy to blow the window but not the tablecloth. For that I need to see where in my image I'm overexposed.

I feel camera manufacturers are too mired in tradition. The idea that because we didn't have tool in the past we shouldn't need them now. Focus peaking is a great example of a new innovation which is a clear improvement on the of film paradigm. If Pentax were to be aggressive about software updates there'd be a huge amount of value in sticking with the brand.

03-13-2013, 12:55 PM - 1 Like   #24
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It's not a bug it's a feature :-)

I've owned a K-01 for less than two months, but I think I understand Pentax's proposition regarding the LCD screen.

The rear screen was designed as a framing and focusing device, such as an optical viewfinder. And, with focus peaking, it excels as such. I've been able to obtain precise focus with my FA 43mm wide open, consistently that is, as I've never been able to do with my K10D.

As a framing and focusing device, if the screen were to appear under or overexposed, focus confirmation could be severely impaired if not just impossible. Not to mention that a severely under or overexposed image simulation would almost completely obscure viewing of the scene itself.

Therefore, the lack of a live exposure preview isn't a bug, it's a feature :-) A quite successful feature, IMHO. I wouldn't change anything.

Notwithstanding the lack of a live exposure preview, the K-01 does offer at least three metering aids (the last two are disabled by default):
  1. An exposure bar, which indicates under and overexposure;
  2. A live histogram; and
  3. Live under and overexposure blinking indications.

I've only enabled the live histogram, because I too think the blinking is too distracting and interferes with the simple viewing of the scene.

And I do find the live histogram useful.

As far as I've been able to observe, the live histogram is actually a preview of the image's histogram if a correct exposure is made as indicated by the exposure bar.

Knowing how to read a histogram chart helps in evaluating if and by how much the exposure bar indication should be overridden. And I've been finding out it works great for me.

Cheers,
03-13-2013, 02:54 PM   #25
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I understand that the histogram is a representation of the LCD (the exposure that the camera thinks is correct).

Sorry if the next question seems dumb...

Let's say that I wanted to do the "expose to the right" technique, how would I know how much overexposure would I need? (without bracketing upwards)
03-16-2013, 10:03 PM   #26
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QuoteOriginally posted by MrSkelter Quote
The Canon G1 X does it. So do many others. They are fixed lens but I don't see why that's a problem. If the camera makes a guess, it can check that guess against the histogram of the exposed frame once it's been shot. In that way the camera can 'learn' the response of each lens.
I'm afraid, you are asking too much of the current generation of cameras. Strange, that you do not see why "guessing" would not work - most lens are quite non-linear, take vignetting for example - how would you estimate the change in histogram (and not overall exposure!) for that? Histogram is just plain math - calculate how many pixels have certain value...

And it is possible to learn, of course - it is called profiling, and it might be feasible in the future... But for now, if camera has fixed lens, manufacturer can "profile" it once and be done with it, but if this is ILC - forget it.

I understand the desire to expose based on histogram shape... This is new technique, which came about with advent of digital P&S-style cameras. But most photographers, who used SLR for advanced amateur or professional shooting know what to do - use light meter... You can try spot metering and measure for highlights, adding +2 EV - this will get your highlights to the right...
03-17-2013, 06:20 PM   #27
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What's going on here? It seems that not many people know how to use these cameras as they were designed to be used. Sorry if that sounds blunt, but I'm so surprised by some of the answers.

Altering aperture or shutter speed won't work as the camera will just compensate in all modes except Manual Mode, use the EV compensation built in - see below.

The beauty of mirrorless cameras is you CAN alter exposure before you press the shutter, you don't have to take an image adjust, take another and adjust etc. etc. as you do with optical viewfinders.

Use Aperture Priority and set the aperture with depth of field in mind. You can use this in all modes, even manual mode.

Set ISO with noise in mind (i.e. as low as possible, just watch the shutter speed doesn't get too slow for hand holding).

Activate the histogram (Camera menu, page 3, Live view, right joggle key (>) check Histogram Display box and/or Bright/Dark Areas box for the blinkies.

Now the histogram will show on the live view screen.

Press and hold the Av button, next to the red button, the EV Compensation scale appears, and alter the e-dial right or left to shift the 'hump' of pixels so they are just short of the right hand edge, you will see the shutter speed altering, click to the left and shutter speed will increase, to the right shutter and speed will decrease, you are now 'exposing to the right' (ETTR - Google it to see the benefits), this setting will maximise the data that the camera will record without any pixels burning out to white, the blinkies serve the same purpose just alter the e-dial whilst holding down the Av button till the blinkies just stop flashing, the red (over-exposed) are more important than the green (under-exposed). You will now get a perfect exposure every time.

I tend to just use the histogram, i find the 'blinkies' distracting, but that's probably just me.

It totally gets around the problem of metering from the camera position which just gives you an average, taking no account of the tone of the subject. Normally any camera will under-expose light toned subjects, snow scenes for example and over-expose dark subject (the ubiquitous black cat on coal), leading to grey snow and grey cats respectively, this method corrects this problem.

There are other advantages to do with the A/D converter too, there being a greater bit depth with pixels on the right of the histogram than those on the left, ETTR maximises data.

Works with any lens.

Chris

Last edited by ChrisJ; 03-17-2013 at 06:47 PM.
03-17-2013, 11:48 PM   #28
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QuoteOriginally posted by ChrisJ Quote
What's going on here? It seems that not many people know how to use these cameras as they were designed to be used. Sorry if that sounds blunt, but I'm so surprised by some of the answers.
I'm all for being blunt, but it seems you didn't carefully read what the OP was asking about.

QuoteOriginally posted by ChrisJ Quote
alter the e-dial right or left to shift the 'hump' of pixels so they are just short of the right hand edge
That's all fine and dandy, but now try that again in fully manual mode (that is dial on M and Auto ISO off). Mount your favorite M42 lens, select a shutter speed on the camera, play with the aperture on the lens and watch the histogram while doing it. What do you see?
03-18-2013, 01:29 AM   #29
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My K-01 is in the post...
enjoying this thread
03-18-2013, 01:27 PM   #30
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QuoteOriginally posted by Ikarus Quote
I'm all for being blunt, but it seems you didn't carefully read what the OP was asking about.



That's all fine and dandy, but now try that again in fully manual mode (that is dial on M and Auto ISO off). Mount your favorite M42 lens, select a shutter speed on the camera, play with the aperture on the lens and watch the histogram while doing it. What do you see?
Thanks for reading the post and understanding the problem. Half the people here are talking down to me and I suspect have never shot their cameras truly manually. They don't even understand the issue.

An invalid histogram is worse than no histogram at all. It's actively misleading and a waste of screen real estate.I shouldn't have to switch it on and off as I change modes.
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