What sort of flash are you using Dr.? What shutter speed? Make sure you are using the flash system designed specifically for this sort of work, and are shooting within the recommended shutter speed range. Probably longer than 1/200sec. Nikon makes a two flash system designed for macro photography, the R1C1 flash system. It retails around $750 USD but you can probably find a used system some where.

Look on page 19 of your owner’s manual. Hold the camera firmly in one hand, and with a finger from the other hand, insert your finger nail under the lip of the bottom edge of the LCD cover and flick it away from the camera. It pops off easily. Clean the LCD and the cover, then reapply starting with setting the cover at the top edge and levering it down so the bottom edge of the cover snaps into place at the bottom edge of the LCD. Done. Give the cover another wipe with a lens cloth and you’re done.

Have you set the viewfinder diopter so that focus is sharp at some point? Are you having the same problem with manual focus lenses? I know that modern autofocus lenses can be calibrated, you may want to check the proper technique for doing so. YouTube is your friend for this sort of thing.

I’ve never known the name but any old bike shop will have a set. Or, if you can find a scrap bike, or a guy that buys and sells bikes from home, they usually have a box of old parts that you can rifle through for these bits.

What exactly did you tighten? The crank bolt that fastens the crank to the axle? Or, the bottom bracket itself? Is the crank loose, or is it the bottom bracket? Isolate the exact problem first before proceeding. Did you remove the crank and tighten the bottom bracket? If you attempted to tighten the bottom bracket (BB) and it is still loose and noisy, it needs to be replaced. Plan on spending about $40 for a replacement. If, you tried to tighten the crank with the single crank bolt, and it is still loose, the inner faces are probably worn so they are no longer square. The crank therefore needs to be replaced. An experienced mechanic can certainly help you diagnose the problem and offer you advice.

Assuming that the viewfinder curtain is out of the way, it sounds like the mirror is locked up. I would take the battery out, make sure it has a full charge and try again. Put the battery in, turn the dial on the top left of the camera to the “S”, single exposure setting and turn the camera on. Does that solve the issue? Is the mirror locked up for cleaning? Check that in your settings too. If not, you need to see a Nikon technician as there may be a physical issue with the mirror.

Do you have any Custom Menus set up? Perhaps if you were to go into these and do a reset, you might solve your issue. Does the problem occur when you are in Manual mode or any other modes?

I’m assuming that you’ve moved the retaining clip to the side. Have you done this with the camera held as you would be shooting? This would allow gravity to let the battery to fall out. You may try giving the camera a sharp thump with your free hand with the camera upright so the battery can fall out. Again, make sure the retaining clip is out of the way first. Try this video.

With the SB600 and above, there is a wide flash adaptor that spreads the beam to its maximum angle of 14degrees. It rests horizontally on the top of the light. You may have pulled it out inadvertently. Use your fingertips to see if the wide flash adaptor is down in front of the bulb. If so, it flips up from the bottom. Lift it back up and tuck it into its pocket on top of the bulb area. When this screen is back in position, you will have full mobility again. If however, you have broken off this screen, you may be able to retrieve mobility with the insertion of a small piece of card (business card?) into the slot where the wide angle adaptor used to be. You will probably have to tape this in place. If this is not the problem and the adaptor is in its storage position, you will have to take the flash to a skilled technician to have it serviced.

Steven I honestly don't feel that the camera being in Portrait mode has anything to do with your black images. Have you verified that there actually are images on the card? Did you have a lens cap on the lens? If anything, portrait mode would have given you a well exposed image. So I don't think that is the cause of the dark image. Verify that an exposure actually took place, but since you say they are black more than likely there is no hope. Sorry.