Flash issue with Canon Speedlite and EOS RP

With my Canon EOS RP and Speedlite (shooting macro), I have a weird problem. Sometimes the flash fires but the camera thinks that it is not on.
When I check the flash settings it says flash turned off - but it is not. This means that the ISO goes to a very high level when not needed and it over exposes. I could just put the ISO to 100 I suppose but I would like to be able to change the flash settings and at the moment sometimes I can't because the camera doesn't think that it is there.
A) Does that make sense
B) Does anyone know how to fix it?

davholla wrote in post #19092475
With my Canon EOS RP and Speedlite (shooting macro), I have a weird problem. Sometimes the flash fires but the camera thinks that it is not on.
When I check the flash settings it says flash turned off - but it is not. This means that the ISO goes to a very high level when not needed and it over exposes. I could just put the ISO to 100 I suppose but I would like to be able to change the flash settings and at the moment sometimes I can't because the camera doesn't think that it is there.
A) Does that make sense
B) Does anyone know how to fix it?

some of the earlier EOS cameras suffered from flash mount screws coming a little loose, haven't heard of any from the R range but suspect it's possible. Does the flash wobble a bit when mounted?

joeseph wrote in post #19092500
some of the earlier EOS cameras suffered from flash mount screws coming a little loose, haven't heard of any from the R range but suspect it's possible. Does the flash wobble a bit when mounted?

I will check, I should have said that I am doing this via a cable but it worked when I first started.

...and make sure the flash is fully forward in the hot shoe. You might also check to see if your firmware is up to date. The latest firmware corrects an issue with some banding at the top of an image when using high speed sync. Although not your issue, sometimes firmware updates fix things.

Can you post an image where the issue may have occurred so we can examine the EXIF and determine your exact settings?

By the way, again not that it is likely to be your problem, but the RP/Speedlight combo treats fill-in flash differently than some DSLR combinations. See the article at https://www.p4pictures​.com …flash-different-eos-r-rp/ for the details.

Years ago on my 7D I had the similar situation. Camera thought the Speedlite was connect and ON even though it was not. After a while I noticed a small fragment under the Camera Hotshoe raising it ever so slightly.
Like other have said, make sure it is clean and screws are snug.
Which Speedlite are you using?
Are you shooting Manual Mode in Camera?
Are your firing your flash in E-TTL or Manual Power?
When you say Macro, how far is the front of the lens from the subject?

Nick5 wrote in post #19092534
Years ago on my 7D I had the similar situation. Camera thought the Speedlite was connect and ON even though it was not. After a while I noticed a small fragment under the Camera Hotshoe raising it ever so slightly.

Nick5 may be referring to an area of the hot shoe that has a very small switch that detects the presence of the flash unit. The attached image is the hot shoe of a 5DIII and you can barely see the switch on the right of the shoe. From some online image of the RP I would have to say that some other method of flash unit detection may be employed as no switch is apparent.

Nick5 wrote in post #19092534
Years ago on my 7D I had the similar situation. Camera thought the Speedlite was connect and ON even though it was not. After a while I noticed a small fragment under the Camera Hotshoe raising it ever so slightly.
Like other have said, make sure it is clean and screws are snug.
Which Speedlite are you using?
Are you shooting Manual Mode in Camera?
Are your firing your flash in E-TTL or Manual Power?
When you say Macro, how far is the front of the lens from the subject?

I will check all these and post a photo tomorrow.
Canon EOS Speedlite 270EX.
Manual
E-TTL
8-50 cm

An example this for some reason overexposed in the past ISO has just automatically changed.
At this time the flash was in theory "off" so I could not change the settings!

I should have said I checked everything and it looked fine - it also worked fine the evening when I did some photography

It appears that Canon's age old nemesis for eTTL hotshoe flash is resurfacing...that it can have a shakey inconsistent contact between the flash and the camera, so that the flash ends up firing full power, rather than the eTTL preflash sensing body sending a command for fractional power to the flash a moment before it triggers it.

I found the problem was worse while using a genuine Canon brand flash extension cord, both the generation 1 cord and the generation 2 cord were tried during evaluation with Flashzebra's support on POTN; although the full power flash (instead of fractional output) could occur with the flash direct in the camera hotshoe as well. No solution could be found for this eTTL shortcoming.

You could put the flash into External mode (photosensor in the flash), but Canon photosensor flash is notorious for underexposing shots (behavior unlike every other photosensor flash on the market). Or use a rough eraser to abraid the contacts of the flash unit and the hotshoe to try for a more consistent electrical contact between flash and camera.