Canon Mirror Lock?

[denmarks]

Hi,

I use my 5DSR mounted in the belly of an airplane to take an image 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 I 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!

[jrhoffman75 · Accepted solution]

"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?"

Yes. The exposure meter can be "fooled" by light entering the eyepiece. It depends on the particular lighting situation. If the belly of the plane is dark the impact would be less than if the camera was set up in bright daylight on a tripod.

[ebiggs1]

No to the first question and possible but unlikely to the second question.

[denmarks]

Hello again,

I'm back on this project, taking a photo every 1.5 seconds for ~4 hours. Still using a 5dsr. Reviewing my comments, I doubt there is still anyway to lock the mirror up (I never look thru the viewfinder). And I haven't heard that there is a risk that the mirror mechanism will bust with all this "abuse". But I have heard that the mirror can cause some blurring in images. I shoot at 1/4,000 to 1/8,000 sec. Is there any chance the mirror vibration can affect sharpness at this speed?

Thanks,

Dennis

[jrhoffman75]

Extremely unlikely at those shutter speeds.

Most guidance speaks to the range of 1/4 second to 1/100 or so as the critical range.

[denmarks]

Ok, thanks again John. I'll try to stop worrying about it...though our next camera for this project will probably be mirrorless.

[ebiggs1]

That is a lot of shots no doubt.   I am glad I am not the one who has to go through all of them.  How often do you shot that many times in a 4 hour session? I have colleagues that have well over 1/2 a million clicks and still going. Your best go is to just use the camera until it needs a new shutter which will still be a long time.  $300 to $350 for a shutter so don't sweat it just use it.

[denmarks]

Thanks for that. We're shooting that rate the whole 4 hours. Yes, it's a lot to go through!

[ebiggs1]

That type of photography is expensive. There’s no way around it and it should be reflected in the price you charge your client.

[denmarks]

Thanks EB. Yes though this is for (sometimes) funded research. The Fujifilm GFX 102mp Medium format camera at $6-10K is a fraction of the cost of say, a Phase One camera. Of course you need lenses too.