Camera technical question EV vs. ISO

[kayest]

I have an Air 2S. The camera aperture is fixed by the hardware. If I shoot in manual and fix the shutter speed, I can still adjust the exposure by changing the EV settings or changing the ISO settings. I presume both of these (EV and ISO) are somehow changing the sensor's light sensitivity, sort of like a gain control. So what exactly is the difference between changing the EV or changing the ISO? What are these settings actually doing to the sensor?

 

[GFields]

I usually if not always use the lowest ISO as possible and leave the shutter speed to auto. I manually adjust the EV only if needed.

 

[AlanL]

Higher ISO numbers will result in higher pixel noise levels so if your goal is the best possible camera capture try to keep it as low as possible. I normally try to fix ISO at a low value if at all possible as gfields already mentioned. I only fix shutter speed if there is some effect I want from a specific shutter speed and noise levels aren't a concern.

 

[Meta4]

I presume both of these (EV and ISO) are somehow changing the sensor's light sensitivity, sort of like a gain control. So what exactly is the difference between changing the EV or changing the ISO? What are these settings actually doing to the sensor?

In photography, there are three things you can adjust to vary exposure: aperture, ISO and shutter speed.
But EV isn't a physical thing that you can adjust.
EV (Exposure Value) is a single number combination of the three exposure settings.

When you have a fixed aperture and lock down the Shutter Speed, the only way to vary exposure is to adjust the ISO value.
When you adjust EV with the settings you described, your camera is adjusting ISO up or down.

If you had locked down the ISO, adjusting EV would have to adjust Shutter Speed to vary exposure.

 

[kayest]

In photography, there are three things you can adjust to vary exposure: aperture, ISO and shutter speed.
But EV isn't a physical thing that you can adjust.
EV (Exposure Value) is a single number combination of the three exposure settings.

When you have a fixed aperture and lock down the Shutter Speed, the only way to vary exposure is to adjust the ISO value.
When you adjust EV with the settings you described, your camera is adjusting ISO up or down.

If you had locked down the ISO, adjusting EV would have to adjust Shutter Speed to vary exposure.

Got it. Thank you, I appreciate the nice clear explanation. Bottom line is that if I fix shutter speed (for video quality) and adjust EV, then in effect, I am changing the ISO. That makes sense.

 

[Smooth Rhythm]

In photography, there are three things you can adjust to vary exposure: aperture, ISO and shutter speed.
But EV isn't a physical thing that you can adjust.
EV (Exposure Value) is a single number combination of the three exposure settings.

When you have a fixed aperture and lock down the Shutter Speed, the only way to vary exposure is to adjust the ISO value.
When you adjust EV with the settings you described, your camera is adjusting ISO up or down.

If you had locked down the ISO, adjusting EV would have to adjust Shutter Speed to vary exposure.

Thanks, Meta4, for that great explanation. Very well written, easy to understand. I am continuing to learn more and more about photography, not there yet, but with members like you around, I’m learning a lot. Thanks for taking the time and effort, as you always do, to share and help other members.

 

[Deleted member 137163]

Thanks, Meta4, for that great explanation. Very well written, easy to understand. I am continuing to learn more and more about photography, not there yet, but with members like you around, I’m learning a lot. Thanks for taking the time and effort, as you always do, to share and help other members.

Questions like this are asked by one but answered for many! I am a long time pilot but love hearing photography tips from those who know. There is a lot of experience and knowledge on this forum.

 

[Dave Maine]

In a general sense, there are three variables used to set the ev. Shutter speed, aperture, and ISO. Any one can be used to establish the desired ev. ISO is not the only choice if you have aperture control.

 

[Dale D]

I have an Air 2S. The camera aperture is fixed by the hardware. If I shoot in manual and fix the shutter speed, I can still adjust the exposure by changing the EV settings or changing the ISO settings. I presume both of these (EV and ISO) are somehow changing the sensor's light sensitivity, sort of like a gain control. So what exactly is the difference between changing the EV or changing the ISO? What are these settings actually doing to the sensor?

I just copy/pasted this from Google

EV is measure of energy, and is equivalent to change by 1 F stop, or double (or half) shutter speed. ISO - International Standard Organization defines range of sensitivity steps expressed in EV values, and also in 1/2 EV, 1/3 EV, or 1/10 EV, that closely correspond to film speeds

 

[Kinner1]

I'm a newbie at drone flying/photography but a photographer by trade. I was nervous to buy a drone for photography that didn't allow me to change my aperture, aka have the "third leg" of exposure. (aperture, shutter speed, ISO) But i love my Air 2s and have stared playing with filters to get the desired effect. It's not easy as you have to go up, access and then RTH and understand what ND filter you need. Its a pain to try, try again. but I have had some good success. Hopefully more as I learn.

 

[Dale D]

I'm a newbie at drone flying/photography but a photographer by trade. I was nervous to buy a drone for photography that didn't allow me to change my aperture, aka have the "third leg" of exposure. (aperture, shutter speed, ISO) But i love my Air 2s and have stared playing with filters to get the desired effect. It's not easy as you have to go up, access and then RTH and understand what ND filter you need. Its a pain to try, try again. but I have had some good success. Hopefully more as I learn.

why not get the M3 which has variable aperture.

 

[hiflyer201]

In photography, there are three things you can adjust to vary exposure: aperture, ISO and shutter speed.
But EV isn't a physical thing that you can adjust.
EV (Exposure Value) is a single number combination of the three exposure settings.

When you have a fixed aperture and lock down the Shutter Speed, the only way to vary exposure is to adjust the ISO value.
When you adjust EV with the settings you described, your camera is adjusting ISO up or down.

If you had locked down the ISO, adjusting EV would have to adjust Shutter Speed to vary exposure.

Hi,Meta
Sorry for this late reply but I haven't been flying for months. Today I tried to lock down my shutter speed for the 180 rule and I couldn't, it just wouldn't stay put. My mavic air 2 was more or less behaving like auto even when set to manual in pro mode. What gives?

 

[Meta4]

Hi,Meta
Sorry for this late reply but I haven't been flying for months. Today I tried to lock down my shutter speed for the 180 rule and I couldn't, it just wouldn't stay put. My mavic air 2 was more or less behaving like auto even when set to manual in pro mode. What gives?

It's hard to say without being able to see it.
If you had it set to manual exposure and and set the shutter speed, the camera should have just used your settings regardless of whether they gave a good or bad exposure.
If the shutter speed wouldn't stay, it sounds like it wasn't actually in manual exposure mode?

If it's giving trouble, try forgetting the 180° "rule" and just using auto settings and see how that turns out.
The 180° rule isn't anywhere near as important as many people think.

 

[hiflyer201]

Thanks so much for the reply. It really had me confused. it would say one thing on the settings but on the screen the shutter speed was different and there was no way to set the ISO..like you say it was like it was in manual. Yaros had written that you could reset the camera settings under the three dots. I did that and that worked. Every thing was normal this morning.
Once again, I very much appreciate all you do for us dummys. Speaking of myself of course.