Blurry images while using my speed light

[vivienne forte]

The D7100 has the ability to fine tune focus on a per-lens basis. If the lens focuses behind where the camera is telling it to focus, am adjustment factor can be entered into the camera using its menus.

It requires some test subject setup, but have a look here.

amazing! I did not know this. Thank you

 

[Tinstafl]

That is a good setup and you should be able to do it all with the 50. I used to shoot that exact same setup. Don’t turn on auto iso as nikon will posh the iso to the max and introduce noise. For fill take your picture with no flash til the background is how you want it. In manual mode then put on the flash to light the subjects. A fast run and gun way on aperture priority is to put the camera on minus .7 exposure comp and the flash on plus .7. This in aperture priority will work but watch your shutter speeds.

 

[wfooshee]

^^^^ Good point about auto-anything, really. Even when you're using flash, the camera's metering system will make every effort to expose with ambient light. If you are in shutter-priority, it will open the aperture as wide as it can go. If you're on aperture priority, you might end up with a 30-second shutter (if it's dark enough.) and auto-ISO, if enabled, will jack the ISO up to what's required, or to your max setting.

Shooting flash, you want to limit these efforts by the camera's metering and put everything manual. Auto modes with auto-TTL flash will do a decent job of exposure if there is good ambient light, and will then give a fairly good fill flash. Without good ambient light, you don't want any camera settings on automatic. Auto-TTL flash is OK, you'll get a good flash picture.

 

[weepete]

I could be wrong, but it looks like a double exposure to me. If the flash is set so it provides a similar amout f light as the ambient lighting you can end up with two exposures in the same image if the subject moves slightly. It's commonly called dragging the shutter, and while it can make some interesting effects it can produce blur like we see on your shots.

When using flash, you need to set your exposure so the ambient lighting is underexposed or turn the flash power down and use the flash as fill.

 

[JBPhotog]

As alluded to in a previous post, you are seeing two exposures, one of the ambient value and one of the flash value during the open shutter phase. The camera is moving during the exposure. Disregard the hard shadow on the background in the family photo on the entranceway, that is produced by the flash. But if you look closely, the shirt buttons also have movement, this is classic camera movement during the exposure.

Keep in mind that on a DX camera, a 50mm lens is the equivalent focal length of a 75mm and with high megapixel bodies these days, 2-2.5x the focal length (75mm) is usually required to eliminate camera movement. Judicious technique is required to shoot at lower than these suggested shutter speeds.

However, you do have options with your D7100 setup to choose higher than typical sync speeds, Custom Settings Menu e1 choose 1/250 (AutoFP) or 1/320 (AutoFP) which lets you go all the way up to 1/8000 with your Nikon speedlite. Usually the ambient is @1 stop less than the flash exposure but try out a few +/- from this starting point to get the look you are after. TTL can be a great place to start off and one has the +/- Flash exposure compensation to get the right balance.

Additionally, I see you were shooting at ISO800, lowering your ISO will reduce the ambient exposure and gain you some IQ at the same time.