speters Loc: Grangeville/Idaho

I never use auto ISO. If I shoot stationary objects, inside or out, I do use manual flash, but never with auto ISO, if I shoot objects with constantly change distance, I shoot in TTL, again not with auto ISO! Even though, I responded to your question, I by no means am a pro, just an amateur!

SharpShooter Loc: NorCal

With all Canon cameras that I have used, it's impossible to shoot Auto ISO if you use a flash.
The camera automatically defaults to ISO 400 so the ISO will NOT vary, no matter WHAT you do with the flash, ttl or manual!!!
My guess is, NO other brand will use Auto ISO with flash either.
SS

G_Manos Loc: Bala Cynwyd, PA

Not necessarily. I recently shot an event indoors, Nikon D750, SB 900 Speedlight, all Manual, Auto ISO. Light was mostly bounced off the ceiling. True enough, most were at ISO 400; however, ISOs varied - 400, 560, 640, 800.

Dun1 Loc: Atlanta, GA

I shoot sports, so I shoot in the AV mode and select my ISO, so I can choose the ISO that allow me a fast enough shutter speed, no less then 1/500 and in some case 1/1,000. I recently shot a session at a golf driving range, and forgot to check the ISO and shutter speed, the subject may have been in focus, the swing, the club head were blurred. I will add the shot was set for a later hour I arrived an hour ahead and the time had been moved due to a cancellation. Haste to set one camera up and shoot quickly made for waste of several shots. If you select you ISO you must check the shutter speed and increase the ISO when lighting changes.
I was a film shooter prior to digital, and I found that as a foundation for being able to shoot manual, and determine the then (ASA) ISO the shutter speed and lens opening. My first camera was a Yashica A, no light meter. Later I purchased a light meter which helped. Then 12 exposures was all film would allow, in some cases 20. Today with digital I may take 12-20 shots of a play, or a batter or pitcher.

donnahde Loc: Newark, DE

I resisted using Auto ISO until recently. I shoot in situations where there is a wide variance in lighting. I have to use a fast shutter speed and the smallest aperture I have at times and the largest at others for more depth of field because I'm rapidly moving from fast action on courts or fields to cheerleaders in often dark areas of the venue to spectators who are also normally in the dark. I set my aperture and shutter speed now (manual mode) and let the camera choose the ISO. I do control the max ISO and the minimum shutter speed. It usually works pretty well although there are times where I will turn it off because I didn't get the exact effect I wanted. For the most part it takes away some of the stress of "having to get the shot".

GoofyNewfie Loc: Kansas City

My findings as well with the Nikon D810 and SB-910.

donnahde Loc: Newark, DE

Not true. Last week I covered a Father Daughter Dinner Dance and decided to try Auto ISO with my Nikon D750 and SB-910 Flash. It worked beautifully!!

BebuLamar

The Canon A-1 has the 4 autoexposure modes including P mode in 1979.

Acountry330 Loc: Dothan,Ala USA

I have a D-800 and use auto ISO almost all of the time when in Manual ode. I can live with the noise most of the time.

therwol Loc: USA

I have to admit that I've never really followed Canon in the film days. I was happy with my Nikon cameras, including the FA that I mentioned. What you are saying is true. The Nikon FA that came along later was more sophisticated in many ways, but I'll admit it wasn't first with multiple shooting modes.