issue with photo speed

Tat

New member
Hi everyone, i am having an issue with my camera. It is most likely a camera setting but i cant find a way to change it.
I shoot at F8 most of the time depending on the light. I have my camera set to Aperture priority with auto iso.
My issue is every photograph is 1/640, it doesn't matter how bright it gets, the speed doesn't change. If i point the camera at the ground the speed drops, if i point the camera at the sun, it jumps to 1/2000 with nothing in between?
I have it set to auto iso and A priority as i photograph birds, i rarely use a tripod so most of my photographs are handheld using my Nikon 300mm f2.8 and a TE III 2x converter. I didnt notice this until i was going through my flickr picks, i am assuming the lens VR compensated and stopped movement blur on my pics?
 

Bikerbrent

Senior Member
Welcome aboard. Enjoy the ride.
We look forward to seeing more posts and samples of your work.

Try shooting some test photos in M "manual" mode with auto ISO off. You use the front and rear command dials to change shutter speed and aperture. If this does not work properly, try a full reset and test again as the command dial assigment may have been changed.
 

Woodyg3

Senior Member
Contributor
Aperture priority will set the shutter and ISO according to the focal length of the lens you are using and the light. There is an algorithm of some sort that adjusts so as to get the "best" setting for the situation. Have you tried it in really dark situations, and if so what shutter speed did it select? If it's still 1/640 then something is wrong.
 

Chucktin

Senior Member
Question: have you looked at the EXIF data to see what the camera setting were?
If you've set Aperature Priority with Auto ISO and you're getting 1/640 in all (most?) shots, what ISO does the EXIF data list?
It's not understood properly nor discussed extensively but ISO on a digital camera is not the response of a film emulsion to light (a chemical reaction) it's the sensitivity of the chip. There's usually a base sensitivity (for the chip) linked to a series of amplifiers that boosts that sensitivity. And when you boost (amplify) the base sensitivity you're also boosting the noise introduced by the amplifying circuitry.
 

Blade Canyon

Senior Member
Maybe that shutter speed was based on the focal length you were shooting? If you were shooting a long lens, the D850 probably figured 1/640 was the minimum shutter speed it could use to deliver a sharp photo, and every other adjustment was made to ISO. Then when you point the camera at a bright sky, it can keep ISO low and raise the shutter speed above the minimum. When you point it at the dark ground, the ISO alone can't compensate, so it has to reduce the shutter speed.

Is there a reason you don't like 1/640?

If you want a particular shutter speed and aperture, then I would put it in M mode, put in the settings you want, and leave ISO on Auto-ISO. That's a great combination for most situations.
 

Tat

New member
Thank you for all of the replies, i have been through all of the settings and by the looks of it, i must have set the minimum ISO shutter speed to 1/640 and the max to 1/2000 myself at some point :)
Anyway, problem solved :)
 
Top