a6k Loc: Detroit & Sanibel

I wonder that someone with so much anti-technology attitude would bother to waste his or her free time to say this. I also find it entirely unsurprising that someone who would mix imperial and metric terms would exhibit that attitude.

And is that the maximum pressure in the cylinder(s) or the mean?

I do suggest however that everyone pay attention to the psi in their car’s tires. Or is that the kPa?

sbohne

"Anti-technology attitude?"

NO.

"Anti-overcomplicated bullsh*t that has little to nothing to do with the end result of the image attitude?"

ABSOLUTELY!

I take my time to create images, not blither, worry, and dither about minutia. I'm not saying it's wrong, mind you. I'm just saying it's of no interest or importance to me. Kind of like worrying about how much Borax was exactly enough in Dektol.

selmslie Loc: Fernandina Beach, FL, USA

If your highlights get blown because this topic is over-complicated then you are doing yourself a disservice by ignoring it.

sbohne

Son, I was probably making GOOD EXPOSURES before you were born. And I knew how to keep from blowing out highlights with the first digital camera I ever owned. But I really do thank you for your sincere concern.

a6k Loc: Detroit & Sanibel

So now you have told us that you are so old you call other senior citizens "son" and that you think that it's important to tell the world that you don't have any interest in the subject but you think we and the OP should CARE that you don't. Really, what does that say about you? Go post your own thread on something that does interest you. We youngsters are having a conversation that does interest us.

BebuLamar

It can make a lot of people's heads hurt but it can also enlighten many people heads. So please allow us to do what we enjoy. If it makes your head hurts please just ignore us.

selmslie Loc: Fernandina Beach, FL, USA

Only if you are in your 90s. This is not my first rodeo.

Get rid of the attitude.

CHG_CANON Loc: the Windy City

The true secret to getting ahead in photography is to worry about the dramatic range and pixel resolution.

TriX Loc: Raleigh, NC

Surprise! There are people that do care. And if you find it uninteresting, just ignore it and go use your camera (even if, like your car, you don’t actually know how it works). I note that you have enough free time to post this.

User ID

You don't have REAL proof. Set your camera
to be running video, put it in the fridge, and
close the door on it. Then review the video.

User ID

Waaaay sageous, mostly.

I don't need to "get ahead". I put it
all BEHIND ! I'm a bene fido retired
staff photographer.

OTOH, if my four mugs of java with
supper are keeping me awake, then
I'll do some of that worrying. And it
is sooooo tiresome that next thing I
know it's already midday tomorrow.

Mentally pixel peep.
Beats counting sheep.

YMMV.

Ysarex Loc: St. Louis

Yes it does (with most cameras I know).

I know with my Canon and Fuji the SOOC JPEGs blow before the raw file reaches capacity. Today I was at the office and I grabbed a Nikon and brought it home. Here's a field test: The raw file has not reached it's limit in the region of the sky marked off. The SOOC JPEG is below and that region of the sky is blown out.

In fact the SOOC JPEG that received 1/3 stop less exposure is still blown out in that region. And in fact in the SOOC JPEG that received 2/3 stop less exposure still has channel clipping in that region and the data is unusable.

Nice charts but now explain why the SOOC JPEG below is nuked while the raw file isn't.

Joe

https://www.dropbox.com/s/dq2tln8hnw9aw7n/_DSC0041.NEF?dl=0

(Download)

SOOC camera JPEG

(Download)

selmslie Loc: Fernandina Beach, FL, USA

That is not a very rigorous test but is in line with with my tabulated results.

In the table I posted at the start of this thread you will see that two of the cameras I tested (Df and the X100T) actually maxed out the JPEG (255) 1/3 stop earlier than the raw file while the other two (A7 II and D610) did not. That's not very conclusive either since all of the tests were separated by 1/3 step increments and the criterion for JPEG blowout is reaching 255. With all four cameras, at 2/3 stop below the raw file limit all of the cameras show a JPEG value lower than 255.

Take another look at the raw histograms for your image with the Y-Axis range set to Logarithm. It shows that the raw file is actually blown out for a small number of pixels. In fact, the left-hand panel below shows that the maximum value in all three channels reaches a limit of 15783 (base 2 log 13.95) which is apparently the maximum value that that particular camera can record - the same as the limit for my A7 II and D610.

Nevertheless, the JPEGs do no blow out (255) any sooner than 1/3 stop below the raw file's maximum with any of the cameras.

(Download)

selmslie Loc: Fernandina Beach, FL, USA

As I just showed, your raw file was actually nuked because some of the pixels reached the camera's maximum raw value of 15783.

Just because 15783 would convert to JPEG 255 does not mean that 15782 would convert to 254. In fact it is likely that 15781, 15780, ..., X would also convert to 255 but X-1 would convert to 254. Is the value of X significant? Probably not. The assumption that 255 is an indication that the JPEG was blown out is not valid or sufficient.

Your exposure was set to 1/640s @ f/5.6 which is EV 14.33. Because of the presence of sunlit clouds I might have used 1/800s, 1/3 stop darker, EV 14.67. You should recognize that as Sunny 16. With 1/3 stop less exposure neither your raw file nor your JPEG would have been blown out. The raw file value would have been closer to 12590 and your JPEG would probably not have reached 255.

Ysarex Loc: St. Louis

Take another look at the raw histogram and consider the context of the image. There's a reason in my original post that I marked off a section of the sky.

There are parked cars on the street catching direct sunlight. The glass and curved gloss-painted surfaces of those cars are generating specular highlights. We know to discard those from an appropriate assessment of the exposure. The section of the sky that I originally marked contains the brightest diffuse highlights in the image. Those highlights have not reached maximum value in the raw file (see below). They are nonetheless blown in the JPEG. They are in fact also blown in the JPEG that received 1/3 stop less exposure.

I loaded that 1/3 stop less exposure JPEG into PS and used Curves to show highlight clipping (see below). That JPEG, also with blown diffuse highlights, is attached and you can see the exposure is 1/800 sec. f/5.6.

The SOOC JPEG is absolutely blowing out before the raw file reaches its limit -- by more than 1/3 of a stop.

Joe

(Download)


(Download)

SOOC JPEG 1/3 stop less exposure

(Download)