Nikon D300 mirror stuck up — sequence seems reversed (software issue?)

[Drumbolt]

Hey all, hoping someone's run into this before.

My D300's mirror is stuck up at rest, and the behavior is backwards from normal:

• Normally: mirror down (viewfinder) → flips up during exposure → drops back down after

• Mine: mirror sits up at rest → when I press the shutter, it drops down → then pops back up and stays there

Mechanically everything seems fine — a local shop tech confirmed the mirror moves freely, spring/hinge are good, no physical obstruction. His read is that it's likely a firmware/software timing issue rather than a mechanical fault, since the motion itself is working, just in the wrong order relative to the shutter cycle.

What I've tried so far:

• Power cycling (multiple times, no motor sound/movement on its own)

• Battery swap (no change)

• Mirror-up cleaning mode toggle

• Two-button reset / reset all settings

• Checking firmware version

Any insight would be greatly appreciated!

 

[Needa]

Re: Tip - Attached lens won't autofocus

Not sure if this is relevant to this make/model, but on Canon body, I was able to reset things by doing the following:

1. Switch off
2. remove battery and card
3. switch on
4. Hold down the shutter for at least 15 seconds
5. switch off
6. re-install battery and card
7. switch on and keep your fingers crossed.

It worked for me and cleared unusual issues I was having with it.
This was apparently a suggestion from a technician in one of their factories and was not widely known in the public domain. It makes you wonder if this is what they do when people send their cameras in for a repair costing a fortune

Try at your own risk!!

Could try this tip! Good luck!

 

[BF Hammer]

There is another mirror up mode where you press shutter release once to raise the mirror, then must press the shutter release a 2nd time to take the photo. This is supposed to reduce vibration from mirror-slap on long exposures. On my D750 and D7000 it was labeled 'MUP' on the function dial and really annoyed me when I accidentally turned it on.

 

[Drumbolt]

There is another mirror up mode where you press shutter release once to raise the mirror, then must press the shutter release a 2nd time to take the photo. This is supposed to reduce vibration from mirror-slap on long exposures. On my D750 and D7000 it was labeled 'MUP' on the function dial and really annoyed me when I accidentally turned it on.

I’ve tried turning on and off the MUP toggle multiple times but that didn’t work either.

 

[BF Hammer]

I have confirmed online that the D300 has LiveView. Switch the lever on the back off of the "LV" position. Your described behavior is how LiveView works.

 

[tonye]

BF, you are a mine of useful information, where do you get it all from, did you used to work for Nikon. Keep up the good work, Hope it works for the fella.

 

[BF Hammer]

BF, you are a mine of useful information, where do you get it all from, did you used to work for Nikon. Keep up the good work, Hope it works for the fella.

I've used various Nikon digital products since 2001 and have made most of the mistakes myself.

In this case I suspected LiveView from the beginning, but I did not know for sure if that was in the D300. Was checking on this between jobs at work on my phone, but now I'm home and can do basic research.

 

[tonye]

Your a legend on here mate.

 

[Drumbolt]

I've used various Nikon digital products since 2001 and have made most of the mistakes myself.

In this case I suspected LiveView from the beginning, but I did not know for sure if that was in the D300. Was checking on this between jobs at work on my phone, but now I'm home and can do basic research.

Hi BF,

It is not live view either. I have toggled Mup and Live View on and off multiple times but neither has changed anything.

 

[Clovishound]

Hope you get this figured out. For better or worse, you can probably get a used D300 for less than a repair. MPB has them for $120 with several units having less than 20,000 shutter activations. Of course the last D300 rolled off the line in 2009, so they are older cameras. In the current world of electronics, 20 years old is ancient. Doesn't mean it's not still a good camera, just things move on quickly in the digital world.

 

[hark]

Did you try what @Needa suggested? It's kind of an electrical reset. When I was out in a snow squall, the shutter button stopped autofocusing. Back button focus worked fine though. Eventually I decided to give those directions a try, and it resolved my camera's issue (it was a D7200 body).