Strange Lens/Flash Behavior With D50

[curritch]

I took some photos tonight with my D50, 18-70mm DX lens and internal flash with

the lens hood in place. A couple of the photos were taken at 18mm and I noticed

a circular under exposed area at the bottom of the photos. I then tried some

experiments and found that this phenomena only occurs at 18mm using the internal

flash with the lens hood in place. Attached are four photos. Number one shows

the phenomena. Number two was at 24mm and it's gone. Number three is at 18mm

without the lens hood and it's gone. Number four is at 18mm with the lens hood

in place but using the SB-800 instead of the internal flash.

 

What's going on here? It's not really a problem now that I know the condition

where it occurs but I am curious as to what is causing this. At first I thought

something had gone south in the camera and/or lens.<div></div>

[frank_skomial]

Remove the lens hood and try again.

Get external Nikon flash that mounts in the hot shoe.

[curritch]

I think I've answered my own question. Apparently the geometry is such that with the low profile internal flash the lens hood is simply blocking the flash illumination in the lower segment of the field of view. Sorry to ask a stupid question.

[lilly_w]

No need to worry as nothing is going south, including the onboard (or built-in) flash output as it is obstructed by the lenshood, which is casting a shadow. The output from the SB-800, sitting atop the hotshoe, is NOT obstructed, permitting the light to go south (bottom of frame), hence no shadow! When using the onboard flash and shooting ultra/superwide (i.e. 18-23 or so) remove the lenshood.

[curritch]

Not to worry though. The photo event of interest was for grandson Eliot to get his Cub Scout Arrow-Of-Light and progress to the BSA. Which he did.

 

The attached photo was taken with the D50, the 70-200mm VR DX lens at 200mm and the SB-800 flash. From about 40 feet away.<div></div>