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Exposure Simulator

andersenimages.com

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Re: Exposure Simulator

#11

Post by sneela »

tiagod wrote: post #10
sneela wrote: post #8

Earlier quoted context omitted.

I recently bought a film camera (Minolta X-700) and I wasted a whole roll because I inverted the aperture (i.e, 2 = sharp, 32 = blur)... I'm interested to see how the roll turns out - gave it for development the other day, had a good laugh with the employees though. I now have a mnemonic for it: Blor - a (somewhat) portmanteau of Blur and low. So low aperture = blur. Edit for clarification: I mean low number (2 vs 32…

High aperture = Blur Unfortunately the lower number actually means bigger aperture.

And that's what exactly confused me :)

With my mnemonic, I say low *number = blur

I should have been more specific

Re: Exposure Simulator

#12

Post by einr »

arghwhat wrote: post #4
ChrisMarshallNY wrote: post #2

That does a fairly good job. I'm sure that image nerds would poke holes in it, but it seems to work pretty much exactly the way it does IRL. The noise at high ISO is where it can get specific. Some manufacturers make cameras that actually do really well, at high ISO, and high shutter speed. This seems to reproduce a consumer DSLR.

With the disclaimer that I am comparing to the memory of some entry-level cameras, I would still say that it's way too noisy. Even on old, entry-level APS-C cameras, ISO1600 is normally very usable. What is rendered here at ISO1600 feels more like the "get the picture at any cost" levels of ISO, which on those limited cameras would be something like ISO6400+. Heck, the original pictures (there is one for each apertur…

Noise depends a lot on the actual amount of light hitting the sensor per unit of time, which is not really a part of the simulation here. ISO 1600 has been quite usable in daylight for a very long time; at night it's a somewhat different story.

The amount and appearance of noise also heavily depends on whether you're looking at a RAW image before noise processing or a cooked JPEG. Noise reduction is really good these days but you might be surprised by what files from even a modern camera look like before any processing.

That said, I do think the simulation here exaggerates the effect of noise for clarity. (It also appears to be about six years old.)

Re: Exposure Simulator

#15

Post by JKCalhoun »

ChrisMarshallNY wrote: post #2

That does a fairly good job. I'm sure that image nerds would poke holes in it, but it seems to work pretty much exactly the way it does IRL. The noise at high ISO is where it can get specific. Some manufacturers make cameras that actually do really well, at high ISO, and high shutter speed. This seems to reproduce a consumer DSLR.

I think it is excellent as well—that it also demonstrates aperture and shutter priority is a bonus.

I do feel (image nerding now) that its shutter/ISO visual for showing the image over/under-exposed is not quite correct. It appears they show incorrect exposure by taking the "correct" image and blend (multiply) with either white or blend with black (on the other end of the exposure spectrum) to produce the resulting image.

I suppose I am expecting something more like "levels" that pushes all the pixels to white (or black) until they are forced to clip. (But maybe I am too trained in photo-editing tools and expect the film to behave in the same way.)

Re: Exposure Simulator

#17

Post by czpl »

trimaster wrote: post #16

Not sure why value on the exposure compensation scale changes in manual mode when ISO is fixed. Shouldn't it be static in that case, unless ISO was in auto?

That's a light meter, not exposure compensation.

Re: Exposure Simulator

#18

Post by Filligree »

sneela wrote: post #11
tiagod wrote: post #10

Earlier quoted context omitted.

High aperture = Blur Unfortunately the lower number actually means bigger aperture.

And that's what exactly confused me :) With my mnemonic, I say low *number = blur I should have been more specific

The aperture size is usually described as e.g. f/32, where f is a camera-specific constant.

Denominator, not numerator. That's why larger number = smaller aperture.

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