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Why is exposure so confusing?
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Jan 22, 2019 18:34:08   #
Bill_de Loc: US
 
Exposure is not confusing, in fact it is damn simple.

Amount of light based on the size of a hole.
Time period for the light based on how long shutter is open.
Sensitivity (sometimes simulated through electronics) decides how much light and time is needed.

What this thread proves over and over again if that humans can complicate the hell out of anything. But as long as we have fun doing it, all is right with the world.

--

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Jan 22, 2019 18:56:58   #
selmslie Loc: Fernandina Beach, FL, USA
 
lamiaceae wrote:
As for lens click stops, I remember my Pentax lenses and Half-stops, and my co-worker's Nikkor lenses (for F & F2) had Third-stops. Today, I can set my cameras to either pattern and also for how it increments ISO and Shutter Speeds.

My Hasselblad film camera lenses use half stops like some of my M lenses. The Rollei TLR uses full stops on the shutter speed and no click stops for aperture, just like my large format lenses.

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Jan 22, 2019 19:05:08   #
srt101fan
 
R.G. wrote:
So the camera lets me think I'm inputting a value of 1/50 when in reality it's going to use a value of 1/64?

On second thoughts, I think I can live with that .

I can think of times when you might want your shutter speed to coincide exactly with the frequency of the mains supply or the frequency of TV or video frame rate, but apart from that, methinks t'is not of any great import.
So the camera lets me think I'm inputting a value ... (show quote)


šŸ˜Š

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Jan 22, 2019 19:10:37   #
Haydon
 
Timmers wrote:
There are two types of people in the world of photography, one group likes to talk about photography, while the other group wants to make photographs.


Funny you mention that. The OP has never posted a single photograph.

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Jan 22, 2019 19:16:57   #
BebuLamar
 
R.G. wrote:
So the camera lets me think I'm inputting a value of 1/50 when in reality it's going to use a value of 1/64?

On second thoughts, I think I can live with that .

I can think of times when you might want your shutter speed to coincide exactly with the frequency of the mains supply or the frequency of TV or video frame rate, but apart from that, methinks t'is not of any great import.
So the camera lets me think I'm inputting a value ... (show quote)


Nope! It would try to do 1/64 is you set the shutter speed for 1/60. If you set for 1/50 it would try to set for 1/50.80 which is very close. The difference in exposure is not what I am concerned about but rather if you use the spreadsheet and it says 1/64 and you can't find 1/64 setting on you camera and it could confuse some people.

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Jan 22, 2019 19:38:10   #
tdekany Loc: Oregon
 
Blenheim Orange wrote:
I welcome his unique point of view. Those who do not are free to ignore the posts that do not interest them.

I don't think it is paranoia to suspect that most online discussions are infiltrated by people with hidden agendas. I have been approached with job offers to work as a troll in the field of food and agriculture, since I am knowledgeable on the subject, have good language skills, and there are commercial interests in the food industry who wish to infiltrate and surreptitiously influence the online discussions about food and farming issues. It is lucrative work, but I didn't go to work in agriculture for the money, and I passed on the offers. It is very rare now to see any online discussion about food and farming issues that is not dominated by what are most certainly paid operatives working undercover for various corporations and lobbying outfits.

Bipod's views on the camera industry are well thought out and well presented. You disagree. So be it. That does not make the other person a "troll" and it is not cause for personal attacks and insinuations. If you do not like these threads, why not stay off of them instead of disrupting them?

Now, I disagree with you om a couple of issues apparently. I thin k I have disagreed with you calmly and respectful. Is that OK with you, or in your view is that proper cause for you to once again make personal attacks against me?

Mike
I welcome his unique point of view. Those who do n... (show quote)


You are one funny guy. Do you actually believe your own claims? Do you think people are being paid to be on this site? That is paranoia.

If I am going to take you and Bipod seriously, I would believe that Bipod is the one who is here with an agenda. He puts down digital at every chance he has. According to him, only large format cameras can take sharp photos and capable of producing deep enough DOF. Maybe, just maybe, Bipod is a schill for a startup large format company and tries to get business by putting down smaller formats. He does that regularly. So do you think maybe he is the one doing it? I donā€™t see anyone doing what Bipod is doing towards large format photography.

I mean, did you realize that your photos are fuzzy?

Come on now, give me a break. Or are you being compensated by Bipod for defending him?

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Jan 22, 2019 19:45:00   #
srt101fan
 
BebuLamar wrote:
Nope! It would try to do 1/64 is you set the shutter speed for 1/60. If you set for 1/50 it would try to set for 1/50.80 which is very close. The difference in exposure is not what I am concerned about but rather if you use the spreadsheet and it says 1/64 and you can't find 1/64 setting on you camera and it could confuse some people.


Methinks you kiddeth, right? Please explain to me what kind of photographer (novice or otherwise) would want to use the spreadsheet, and then gets confused because they can't match the spreadsheet and camera settings?

Have we landed in the Land of Oz? šŸ˜•

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Jan 22, 2019 19:52:43   #
tdekany Loc: Oregon
 
srt101fan wrote:
Methinks you kiddeth, right? Please explain to me what kind of photographer (novice or otherwise) would want to use the spreadsheet, and then gets confused because they can't match the spreadsheet and camera settings?

Have we landed in the Land of Oz? šŸ˜•


The twilight zone!

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Jan 22, 2019 19:54:25   #
AndyH Loc: Massachusetts and New Hampshire
 
BebuLamar wrote:
'CAUSE I DON'T WANT TO COUNT CLICKS.


I can count clicks without looking in the viewfinder. And my meter displays nice clear 1/3 stop increments for over and under. Personally, I donā€™t care whether itā€™s f/5.6 or f/5.73097654321, as long as itā€™s 1/3 of a stop.

Andy ā€œI was told there would be no math involvedā€ H

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Jan 22, 2019 20:07:44   #
srt101fan
 
AndyH wrote:
I can count clicks without looking in the viewfinder. And my meter displays nice clear 1/3 stop increments for over and under. Personally, I donā€™t care whether itā€™s f/5.6 or f/5.73097654321, as long as itā€™s 1/3 of a stop.

Andy ā€œI was told there would be no math involvedā€ H



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Jan 22, 2019 20:10:03   #
kymarto Loc: Portland OR and Milan Italy
 
Bipod wrote:
It time someone talked about WHY exposure is so confusing.

It's because of the way manufacture's label camera settings. They don't apply base 2 logarithms
consistently.

There are two reasonable rules:
1. Each detent on a control (aperture, shutter, ISO, exposure compenstation) must be EXACTLY
twice (or half) the exposure of the previous detent; and
2 Each should be labeled in integers: ... -3, -2, -1, 0, 1, 2, 3....

If you do this consistantly, you get the Additive Photographic Exposure System (APEX)
which was standardized way back in 1960 (ASA standard ASA PH2.5-1960) and was used
in industry and by the military (where confusion is not OK).

EC knobs (and menus) generally follow both rules: No compensation is labeled "0". Increasing
exposure by one stop is labled "1". Decreasing exposure by one stop is labeled "-1". Anyone
confused by this? Pretty simple, right?

F-numbers follow Rule 1, but not Rule 2. The sequence 1, 1.4, 2, 2.8, 4, 5.6, etc. is a lot more
complicated than 1,2,3,4,5... And you don't need to know the actual f-stop ratio unless you are
building a camera.

Shutter speeds are a mess. They follow neither rule. This sequence makes sense:
1, 2, 4, 8, 16, 32, 64, 128, 256, 512, .... This one doesn't: 1, 2, 4, 8, 15, 30, 60, 125, 250, 500, .....
What's the rule for latter sequence, pray tell?

ISO speeds are given in two different sysems: ASA and DIN. Both follow Rule 1, but only DIN
follows Rule 2. The ISO "standard" is to use BOTH! (Sure sign of a gutless committee trying to
please everybody.) The ASA number isn't even logarithmic. And ASA 100 is DIN 21 -- why 21?
"Historical reasons".

Finally, Exposure values follow Rule 1 but not Rule 2 -- again for "historical reasons".
"Historical reasons" is a polite way of saying S.N.A.F.U.

Exposure is confusing because of the silly, stupid, inconsitent way in which cameras controls
are labeled.

Here's the "Sunny 16" rule in the traditional Tower of Babel system:

At approx. EV 15 and f/16, use shutter speed 1/ASA speed
for example:
At approx. EV 15 and f/16 and ASA 100, use 1/100th sec

(which of course, isn't even a detent on the shutter dial-it only has 125.)

Here the general rule in APEX:

TimeValue + ApertureValue = SensitvityValue + Brightness
E.g., at approx. EV 15:
5 + 8 = 5 + 8

Does this math confuse anybody? Dang simple, if you ask me.
So by subtracting SensitivityValue from both sides:

Brightness = TimeValue + ApertureValue - SensitivtyValue
8 = 5 + 8 - 5

As usual, people are willing to update their hardware and software (= buy stuff) but not their thinking.
Picture a cave man holding a Nikon. "Og like take photos. But Og confused by exposure." No wonder!


For reference, here's the basic system, as standardized in 1960.

APEX SYSTEM (per ASA PH2.5-1960)

Note: this may differ from EXIF Version 2.2.

APERTURE

f-number APEX
1 0
1.4 1
2 2
2.8 3
4 4
5.6 5
8 6
11 7
16 8
22 9
etc.

SHUTTER SPEED

The original APEX standard kept the irregular shutter times: 1, 1/2, 1/4,1/8, 1/15, 1/30, 1/60, 1/125....

In fact, some cameras are already calibrated to 1/16, 1/32, 1/64... Shutters are rarely accurate enough
to tell the difference except at 1/15 <> 1/16.

Nominal Sec. APEX
1 1 0
2 1/2 1
15 1/15 2
30 1/30 3
60 1/60 4
125 1/125 5
250 1/250 6
500 1/500 7
1000 1/1000 8
etc.

FILM/SENSOR SPEED


ASA DIN APEX
100 21 5
200 22 6
400 23 7
800 24 8
1600 25 9
etc.


BRIGHTNESS

Again, the original standard kept the irregular shutter speeds, so it had to have
irregular brightnesses as well.


APEX FOOT LAMBERTS
1 2
2 4
3 8
4 15
5 30
6 60
7 125
8 250
9 500
10 1000
etc.
It time someone talked about WHY exposure is so co... (show quote)


American? Still using Imperial units?

Actually there is an excellent reason to use f stops, to know the actual aperture. Arbitrarily labeling by integers would be silly. Is the "1" of one lens the same as the "1" of another? Exactly what does a "1"correspond to, simply the maximum aperture of a given lens?

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Jan 22, 2019 20:12:06   #
AndyH Loc: Massachusetts and New Hampshire
 
Can I use a Whitworth change to change my f/stop on a non-Lucas lens?

Andy

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Jan 22, 2019 20:23:47   #
Blenheim Orange Loc: Michigan
 
tdekany wrote:
You are one funny guy. Do you actually believe your own claims? Do you think people are being paid to be on this site? That is paranoia.

If I am going to take you and Bipod seriously, I would believe that Bipod is the one who is here with an agenda. He puts down digital at every chance he has. According to him, only large format cameras can take sharp photos and capable of producing deep enough DOF. Maybe, just maybe, Bipod is a schill for a startup large format company and tries to get business by putting down smaller formats. He does that regularly. So do you think maybe he is the one doing it? I donā€™t see anyone doing what Bipod is doing towards large format photography.

I mean, did you realize that your photos are fuzzy?

Come on now, give me a break. Or are you being compensated by Bipod for defending him?
You are one funny guy. Do you actually believe you... (show quote)


Even if we stipulated that what you say about Bipod is true, he is - at worst - criticizing inanimate objects, cameras. You, on the other hand, are attacking fellow UHH members. See the difference?

He does not "put down digital at every chance he has," but even if he did, so what?

He does not say that "only large format cameras can take sharp photos nor that "only large format cameras and capable of producing deep enough DOF," but again, even if he were, so what?

Why so hostile and defensive? It seems that you might suspect that Bipod is right, since you seem to feel so threatened by his observations. I don't. Of course my photos are "fuzzy" - that is to say, there is a certain amount of diffraction involved in DSLR 35mm equivalent images at f/16, there are trade-offs that I acknowledge and accept.

If you don't find other member's interesting or valuable for you, then why not simply ignore them? Or, if you disagree with what someone posts, why not put together a persuasive counter-argument, rather than making these petty little personal attacks?

Bipod is "putting down smaller formats" according to you. You are putting down people, members here at UHH. Those are not equivalent. An attack on a format is not an attack on you personally, nor is it a justification for you to go after other members.

Mike

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Jan 22, 2019 20:32:30   #
BebuLamar
 
srt101fan wrote:
Methinks you kiddeth, right? Please explain to me what kind of photographer (novice or otherwise) would want to use the spreadsheet, and then gets confused because they can't match the spreadsheet and camera settings?

Have we landed in the Land of Oz? šŸ˜•


Scotty posted a spreadsheet. I said it's good but the problem with using a spreadsheet or calculators the values you get won't match that on the cameras. It's not that the calculations not correct but rather the marking on cameras are done using conventional values that were not accurate. The error isn't big but simply cause some confusion.
If you make the spreadsheet you wouldn't be confused but if you use someone else you may as you really don't know how it does it.
I only wanted to tell Scotty that is why I would simply memorize all the values used traditionally than do the calculations.

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Jan 22, 2019 20:44:41   #
lonewolf456
 
I'm starting to question my decision to be part of the Hog forum. Seems the technical peeps insist on talking about highly technical preferences which most people don't understand and have little interest or knowledge. I'm into photography for fun, not dissecting the numerous options available with most DLSR cameras. Keep it simple, and you keep me. Otherwise, I'm packing my bags.

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