topic Re: Mirror Lock in EOS DSLR & Mirrorless Cameras

D70 Can I Lock the SCN and CA settings?

timb12957 — Fri, 02 Nov 2018 02:53:43 GMT

In SCN or CA mode after I set the desired parameters can I lock them so when I switch modes then come back the parameters will still be where I set them?

Re: D70 Can I Lock the SCN and CA settings?

Tim — Fri, 02 Nov 2018 04:42:27 GMT

Hello timb12957,

The SCN and CA modes do not lock in the settings in the case you were to switch modes.

Mirror Lock

denmarks — Sat, 03 Nov 2018 01:36:44 GMT

Hi,

I use my 5DSR mounted in the belly of an airplane and taking a picture once a second for 4 hours at a time. I don't look through the camera and would rather the mirror not take all that abuse. On the old SLRs, you could manually lock the mirror up and keep it up. I know there's a feature on the 5dsr that they CALL mirror lock but it just lets you delay the shutter a second or two after the mirror flips up...which wouldn't work for what we do. Does anyone know a way to lock it up and keep it up?

Separately, the Canon manual says: "When you use a remote switch and do not look through the viewfinder, stray light entering the viewfinder can cause the picture to look dark. To prevent this, use the eyepisece cover." I don't understand. Could this affect photos?

Thanks!

Re: Mirror Lock

Tim — Sat, 03 Nov 2018 02:36:15 GMT

Hello denmarks,

Yes, on some older film SLR cameras, one could lock up the mirror in a different fashion than the mirror lockup that is offered today. The mirror lockup seen on cameras today is intended as method to eliminate blurred photos which might occur from the vibrations of the mirror. In effect the principle is the same except it's limited to single shot shooting. So once it takes the shot the mirror goes down. There is no method in camera to force it to stay open and allow the camera to continue taking shots as you've suggested. If you are looking for a camera that would not have the wear and tear on the mirror, you may wish to look into one of the Canon mirrorless cameras, like the EOS M50 or the new EOS R.

Yes, like the manual says, "When you use a self timer, bulb or a remote switch and do not look through the viewfinder, stray light entering the viewfinder can cause the picture to look dark. To prevent this, use the eyepiece cover." The reason for this is because, as the manual points out stray light can enter into the camera through the viewfinder when the mirror is locked up.

Re: Mirror Lock

denmarks — Mon, 05 Nov 2018 19:58:49 GMT

Thanks Tim,

I did read that in the manual, but don't really know the mechanism for where the light finds its way to the metering sensor so don't know the risk. If it can happen when the mirror is in "locked" mode where it flips up a second before the shutter, I would think it could also happen any time during a normal shot too and ALL photos should have either your eye, or a viewfinder cover, over the viewfinder during shooting.

Re: Mirror Lock

Waddizzle — Tue, 06 Nov 2018 00:20:01 GMT

@denmarks wrote:
Thanks Tim,

I did read that in the manual, but don't really know the mechanism for where the light finds its way to the metering sensor so don't know the risk. If it can happen when the mirror is in "locked" mode where it flips up a second before the shutter, I would think it could also happen any time during a normal shot too and ALL photos should have either your eye, or a viewfinder cover, over the viewfinder during shooting.

How does it happen? The viewfinder contains a pentaprism. The metering sensor is located just above it.

When light enters the DSLR body from the lens, it hits a mirror that reflects most of the light upwards towards the pentaprism in the viewfinder. A small portion of the light is reflected downward to the AF sensor. When light enters the pentaprism, it gets split again, with some light continuing upwards to the metering sensor, while the rest is diverted towards the eyepiece.

Re: Mirror Lock

denmarks — Tue, 06 Nov 2018 01:13:53 GMT

Ah...so it makes sense then that light going the other way, FROM the eyepiece can also enter the pentaprism and go up to the metering sensor and affect the exposure. I think I'll find the eye caps and use them. Can't hurt. Thank you.

Re: Mirror Lock

denmarks — Tue, 06 Nov 2018 01:20:04 GMT

Thanks. I did look into the mirrorless cameras a little while back. I really do use all 50mp of the 5dsr so they won't quite work for me.
"Accept as Solution" doesn't appear on most replies...I saw it on one and used it.

Re: Mirror Lock

denmarks — Tue, 06 Nov 2018 01:26:53 GMT

Not only do i not see all the buttons referred to, but I rarely see the icons that let you start a new thread. Do you know if this is a common issue on this site?

Camera won't power on

denmarks — Tue, 06 Nov 2018 01:34:49 GMT

I have a few 5dsrs that I use in aircraft...which vibrates a fair amount. On my last trip, one stopped powering on. I switched batteries, connected it ot an AC adapter...nothing. I was planning on sending it in for repair but it's turning on now. I'm a little concerned that if I send it in and it's working normally, the problem won't get found...though I would hope the technicians would look at it as if it was not powering up. Is this an intermittant problem others have had? Thanks.

PS. I keep having to start a new thread by hitting "Reply" and changing the subject line...because I don't get the new thread icon showing up (it did once). Is this a problem on this site? Not sure if it really gets out as a new thread.

Re: Camera won't power on

Crista — Tue, 06 Nov 2018 01:57:55 GMT

Hi denmarks!

Thanks for posting in the Canon Forums!

If you want to create a new thread, all you need to do is go to the board you want to post on and you should see a Post Message button. Once you're on the Post Message page, you will see a Subject area and a Body area. From there you can compose your post and hit Submit Post to post it to the board for everyone to see. These instructions may vary based on if you're visiting the Canon Forums from a computer or a mobile device. We recommend using a computer for the best results.

We hope this helps!

Re: Camera won't power on

denmarks — Tue, 06 Nov 2018 02:08:49 GMT

Thanks,
I don't get the Post Message button but I do get a New message button, which looks like it will work. I do use a computer with Chrome. Maybe Explorer works better...