+and - EV: Ok, I'm reading about my Canon 5d Mark IV. I'm shooting in mostly manual. I come across this sentence and I'm confused. Here is the sentence. "The center point can function...

Tracy B. Loc: Indiana

Ok, I'm reading about my Canon 5d Mark IV. I'm shooting in mostly manual. I come across this sentence and I'm confused. Here is the sentence. "The center point can function down to -3 EV for working in extremely dim lighting." My question is: If your working in dim lighting, wouldn't you be moving the EV +3? Clearly, I'm missing something.

HEART Loc: God's Country - COLORADO

Picture-Correct easy-peazy instr. http://www.picturecorrect.com/tips/what-is-an-f-stop/

Best wishes with your new Canon!

jimvanells Loc: Augusta, GA

I think that comment means your center focus point has a dynamic range of 6 stops. If you exposure is in that range the camera can focus accurately. I have mine set to "no focus, no exposure". I also shoot in manual and keep the exposure meter in the bottom of the viewfinder. I have had my 5d4 for a month and am still working out the details myself. Other Hoggers with more experience, if I'm off base, please let us know.

Tracy B. Loc: Indiana

HEART wrote:

Picture-Correct easy-peazy instr. http://www.picturecorrect.com/tips/what-is-an-f-stop/

Best wishes with your new Canon!

Thank you for the link.
I understand f stop, aperture, shutter speed, iso, I shoot in manual so I understand the exposure triangle. I was just confused by this sentance.

Tracy B. Loc: Indiana

jimvanells wrote:

I think that comment means your center focus point has a dynamic range of 6 stops. If you exposure is in that range the camera can focus accurately. I have mine set to "no focus, no exposure". I also shoot in manual and keep the exposure meter in the bottom of the viewfinder. I have had my 5d4 for a month and am still working out the details myself. Other Hoggers with more experience, if I'm off base, please let us know.

That totally makes since. Sometimes I read too much in something and I get stuck there.
Thank you for answering my post.

burkphoto Loc: High Point, NC

Tracy B. wrote:

Ok, I'm reading about my Canon 5d Mark IV. I'm shooting in mostly manual. I come across this sentence and I'm confused. Here is the sentence. "The center point can function down to -3 EV for working in extremely dim lighting." My question is: If your working in dim lighting, wouldn't you be moving the EV +3? Clearly, I'm missing something.

In photography, exposure value (EV) is a number that represents a combination of a camera's shutter speed and f-number, such that all combinations that yield the same exposure have the same EV (for any fixed scene luminance). EV normally relates directly to light level required for exposure at a given ISO.

This is a screenshot of MyLightMeter iPhone app... note the matchup of aperture and time for the current ISO and EV number.

Tracy B. Loc: Indiana

I guess I didn't explain myself that correctly. I know what EV is. The "actual "sentence confused me. "The center point can function down to -3 EV for working in extremely dim lighting." I was thinking "Ok, it's dark why would I move the EV (-) instead of (+)?" I believe jimvanells, answered what I was looking for. Thank you for replying everyone.

burkphoto Loc: High Point, NC

Tracy B. wrote:

I guess I didn't explain myself that correctly. I know what EV is. The "actual "sentence confused me. "The center point can function down to -3 EV for working in extremely dim lighting." I was thinking "Ok, it's dark why would I move the EV (-) instead of (+)?" I believe jimvanells, answered what I was looking for. Thank you for replying everyone.

Yes he did! I too thought of exposure compensation...

Gene51 Loc: Yonkers, NY, now in LSD (LowerSlowerDelaware)

Tracy B. wrote:

Ok, I'm reading about my Canon 5d Mark IV. I'm shooting in mostly manual. I come across this sentence and I'm confused. Here is the sentence. "The center point can function down to -3 EV for working in extremely dim lighting." My question is: If your working in dim lighting, wouldn't you be moving the EV +3? Clearly, I'm missing something.

Tracy, the Canon literature is referring to EV as an absolute value for a lighting situation that corresponds to a combination of aperture, shutter speed and ISO. A value of -3 EV is F2.8 and 60 secs @ ISO100. Most EV charts are calculated at ISO 100.

http://www.scantips.com/lights/evchart.html
https://en.wikipedia.org/wiki/Exposure_value

As the first article explains, of you are using a combination of settings that gives you an EV of 10 and your ISO is set to 100, you would use the 10th row. If you change your ISO to 1600, you would need to use row 14 for your exposure settings, and so on.

(Download)

Tracy B. Loc: Indiana

Gene51 wrote:

Tracy, the Canon literature is referring to EV as ... (show quote)

Oh, thank you for the information! So interesting. I can see where I got confused. I'm glad these forums are here to ask questions. I could have looked all day on the Internet and be looking in the wrong direction.

Tracy B. Loc: Indiana

burkphoto wrote:

Yes he did! I too thought of exposure compensation...

Yes, I'm confusing EV with Exposure Compensation. Oops.

Bill_de Loc: US

I think the point of the original sentence was just to say that in low light a/f will continue to work if you use the center point only, even if it fails when using multiple points.

The same is true with Nikon, although I've never seen a specific E/V.

Of course I could be wrong.

--

Tracy B. Loc: Indiana

Bill_de wrote:

I think the point of the original sentence was just to say that in low light a/f will continue to work if you use the center point only, even if it fails when using multiple points.

The same is true with Nikon, although I've never seen a specific E/V.

Of course I could be wrong.

--

Interesting. I can see that also.

SharpShooter Loc: NorCal

Tracy B. wrote:

That totally makes since. Sometimes I read too much in something and I get stuck there.
Thank you for answering my post.

LoL, now that you understand, go out and take pictures!!!!

SS

Tracy B. Loc: Indiana

SharpShooter wrote:

LoL, now that you understand, go out and take pictures!!!!

SS