Why NO picture files?

[Manfred M]

Whilst you may have disabled it for those reasons you are using a DSLR. It's ineffectiveness with respect to mirrorless is that it can not be recognized, not how annoying it can be.



Surely you can hardly call a feature that assists you achieving focus in very low light situations when using mirrorless "useless".

Frankly, I find many of the features that camera manufacturers include with the cameras they sell us useless. If I did other genres of photography, I might find some of them useful, but as most of my work is either done in a studio or when I am travelling there are things I and use.

For example, I don't find multi-focus points useful and virtually always use a single focus point. I dislike the way metering, focus and shutter release are all locked into a single function (pressing the shutter release half-way) and have been using back-button focus for years.

On the other hand, the manufacturers have removed features that I find useful, like depth of field markings on the lenses.

I do understand that I don't shoot the way other people do and appreciate why manufacturers do include all that functionality.

[Stagecoach]

Frankly, I find many of the features that camera manufacturers include with the cameras they sell us useless. If I did other genres of photography, I might find some of them useful, but as most of my work is either done in a studio or when I am travelling there are things I and use.

For example, I don't find multi-focus points useful and virtually always use a single focus point. I dislike the way metering, focus and shutter release are all locked into a single function (pressing the shutter release half-way) and have been using back-button focus for years.

On the other hand, the manufacturers have removed features that I find useful, like depth of field markings on the lenses.

I do understand that I don't shoot the way other people do and appreciate why manufacturers do include all that functionality.

All very well, but the thread is surely about the Ops unknown problem whilst using their gear in a specific scenario, not what you like or don't like.

[Manfred M]

All very well, but the thread is surely about the Ops unknown problem whilst using their gear in a specific scenario, not what you like or don't like.

Agreed, but we are all just guessing at what might have gone wrong and there are many possible causes that have been listed. Without more information, it is going to be very difficult to narrow things down.

[Stagecoach]

Agreed, but we are all just guessing at what might have gone wrong and there are many possible causes that have been listed. Without more information, it is going to be very difficult to narrow things down.

Exactly, hence an understanding of what possible causes could be to help with elimination testing.

[odds]

...The only time we actually see two flashes is when red-eye reduction is turned on.

If the shutter button is half-pressed and then released, there will only be the red-eye flash, and no file?

--
OddS

[Manfred M]

If the shutter button is half-pressed and then released, there will only be the red-eye flash, and no file?

--
OddS

No, I don't believe this is possible in the no file written scenario.

My original comment was that I did not believe that people were seeing the pre-flash, because in all instances that I have ever seen the pre-flash (to determine exposure) and the flash occur so quickly that most people are not capable of detecting the pre-flash as both occur almost simultaneously. The exception would be when the camera is set to second curtain / second shutter configuration with a suitably slow shutter speed. The only time, in my experience, where people notice two flashes is when the "Red Eye" removal function has been selected. Here we do have a significant and noticeable delay between the red-eye flash and the pre-flash / flash in order to give the eye's iris enough time to react and close down a little. All of these functions are part of the shutter release cycle and cannot result in a no image written situation.

The only way that I know of triggering a speedlight without having the camera trigger it is to push the test button. Push that and the flash will go off and the camera will not record an image.

The only other light source on either the camera or flash are the focus assist lights and I have no idea as to how or if they are implemented on EOS-R or EL-100.

[DanK]

I use a different flash and don’t have it with me to check, but I shoot with Canon and have a few ideas that might help.

Canon cameras allow you to set whether the shot will be taken if focus hasn’t been achieved. On my R6 II, this is called “one shot AF release prior” and is in the AF 3 menu. I think that by default it’s set not to trip the shutter if focus hasn’t been achieved. I always change that setting. Perhaps it was the issue.

On some Canon bodies, pressing the DOF preview button next to the lens will cause a shoe mounted flash to fire, although multiple time if you hold it down. I’ve don’t that accidentally a number of times.

I’m any case, if there were no files, the shutter didn’t trip.


Sent from my iPad using Tapatalk

[ajax]

...
Canon cameras allow you to set whether the shot will be taken if focus hasn’t been achieved. On my R6 II, this is called “one shot AF release prior” and is in the AF 3 menu. I think that by default it’s set not to trip the shutter if focus hasn’t been achieved. I always change that setting. Perhaps it was the issue.

My EOS R camera puts it on the AF4 menu and it looks like you can set it to "Focus" or "Release". It is set to "Focus" (by default I believe) which says "No shot will be taken until subject is in focus". Also, right next to it there is a setting called "AF Assist Beam Firing" which is turned on.

When it comes to the menus on my camera there is only 1 sub-menu item under AF (i.e., AF1) when I have the camera in fully automatic mode like when I was trying to take the picture. I would assume that is to prevent anything from being changed. Not sure whether that means the manufactured settings are used or the custom changes that may have been set when in a different mode. However, in this case I'm pretty confidant that none of the settings have been changed from those set by manufacturer.

The camera was set to fully automatic mode at the time of the result being being discussed herein.

On some Canon bodies, pressing the DOF preview button next to the lens will cause a shoe mounted flash to fire, although multiple time if you hold it down. I’ve don’t that accidentally a number of times.
...

Sent from my iPad using Tapatalk

I can't find anything called a DOF Preview button on my camera.

[ajax]

Based on discussion herein, I'm thinking the likely explanation for the failure to take (record) any shots (pictures) pertains to the related auto focus features. In hind sight my big mistake was over simplifying what needed to be done to take a shot. Clearly I should have verified that my volunteer assistant knew what to do by having him shoot a picture and verify that it happened before leaving him to shoot the wanted pictures on his own.

Something I had done on my own was to shoot a picture of the patio scene in order to verify what kind of result I expected before asking the group to pose for the picture. I've attached the camera developed preview image from the raw file recorded when shooting that picture. While not great I thought it good enough to be worth asking the group to pose. I do have some knowledge and experience developing raw files which I thought might allow a decent final picture to be produced.

I certainly do NOT know for sure whether or NOT the flash fired during auto focus but it was possible. I have NO idea what criteria would have been used by the camera to determine that focus could NOT be achieved and then end up not releasing the shutter and taking a picture but it seems that this is how AI is supposed to work. Even with the new knowledge obtained from this discussion I'd have thought it worth trying to take the picture. Clearly something that went wrong was failing to perform real time verification.

[ajax]

Another thought which, I think, has to do with the very nature of artificial intelligence. In that, we don't really know what's going on. While auto focus is pretty amazing, figuring out what went wrong here becomes difficult when uncertain about what the camera is doing. For example, when experimenting to figure out what went wrong I was inclined to think that doing tests with less rather than more light ought to help reproduce the problem. However, when referring to focus, I suppose, a completely black picture could be considered to be in focus rather than out of focus. Likewise the referenced trial picture is a pretty benign scene but when you add 50+ people in front of that bush it gets a little more complicated (i.e., maybe more rather than less difficult to focus automatically). Also, when in fully automatic mode the camera is set to something it calls "facial tracking". Who knows what that does but going from zero to 50+ faces might have an affect.

[DanK]

My EOS R camera puts it on the AF4 menu and it looks like you can set it to "Focus" or "Release". It is set to "Focus" (by default I believe) which says "No shot will be taken until subject is in focus".

Exactly. I think it's very likely that this was your problem. If the camera was unable to focus, perhaps because it was so dark, it wouldn't take a photo. I've had a bunch of Canon bodies, and I have never left that option set to "focus" rather than "release"

Re DOF preview: I see online that the R doesn't have that control. However, that was a long shot guess anyway, as that generally causes the flash to strobe rapidly, which isn't what you described.

[mjdl]

I'm not a flash user, but I do see on the SHOOT 2 menu of my Canon RP an item "External Speedlite Control" that according to the manual, once activated, is supposed to allow complete control over the Canon Speedlite from the camera via sub-menus from that item. Among those sub-menus is one that enables/disables the flash itself. The manual is silent on whether the flash is automatically enabled once attached to the camera (and I am not sure how flashes work).

[loosecanon]

I do use flash sometimes.
Two possibilities exist
On half pressing the shutter release the pre flash will fire to set exposure and also try to focus. Someone not used to the camera in the dark may assume the preflash is the flash and the shutter has fired when in fact it has not.
The camera was set not to fire if focus not obtained, in which case only the preflash would be seen, but again shutter not fire.
In the circumstances described the shutter has not fired, otherwise there would bee a very dark inage but we are told no image recorded.

Moral of tale - when getting someone to operate your camera demonstrate how to do it, and then let them take a test shot and show them how the image comes up on the back screen to check it worrked OK. May also be sensible to do a manual prefocus or show them how to tell it has focused, ie colour change of focus point.