Velbon Super Slider: I have a new Velbon Super Mag Slider for fine focusing. When I put it on the tripod and attach camera it will slide back and forth, but the focus doesn't change.

bohleber Loc: southern Indiana

I have a new Velbon Super Mag Slider for fine focusing. When I put it on the tripod and attach camera it will slide back and forth, but the focus doesn't change. Canon 6D, 100mm Macro lens, set on manual focus on the lens and in the camera. Focusing ring on lens works. What am I doing wrong? Help please.

Thanks, Don

rwilson1942 Loc: Houston, TX

I assume you are moving the knob on the slider one revolution at a time.
If so the focus is only going to move 2mm if I remember correctly for that slider.

bohleber Loc: southern Indiana

I can move the slider from one end to the other and the focus doesn't change.

Gene51 Loc: Yonkers, NY, now in LSD (LowerSlowerDelaware)

bohleber wrote:

I can move the slider from one end to the other and the focus doesn't change.

What is your working distance from sensor to subject?

bohleber Loc: southern Indiana

6'

rwilson1942 Loc: Houston, TX

bohleber wrote:

6'

You are only moving the camera 2 inches, that's not much compared to 6 feet.
The slider is intended to make small movements while shooting macro shots.
Try shooting something near the minimum focus distance of the lens.

bohleber Loc: southern Indiana

TY RWilson

bohleber Loc: southern Indiana

RWilson, Even with the lens 6" from the subject, the focus stays the same from end to end????

Gene51 Loc: Yonkers, NY, now in LSD (LowerSlowerDelaware)

rwilson1942 wrote:

You are only moving the camera 2 inches, that's not much compared to 6 feet.
The slider is intended to make small movements while shooting macro shots.
Try shooting something near the minimum focus distance of the lens.

RWR Loc: La Mesa, CA

bohleber wrote:

I have a new Velbon Super Mag Slider for fine focusing. When I put it on the tripod and attach camera it will slide back and forth, but the focus doesn't change. Canon 6D, 100mm Macro lens, set on manual focus on the lens and in the camera. Focusing ring on lens works. What am I doing wrong? Help please.

Thanks, Don

It takes a bit to get used to. Try this. Set the lens at or close to its minimum focus distance, and the rail at about its middle of travel. Now move the whole rig in close to the subject until it looks fairly clear, then fine tune your focus with the rail. The advantage with the rail is that you can focus while maintaining the reproduction ratio (subject size), whereas if you focus with the lens you are also changing the ratio, which may or may not be desirable.

speters Loc: Grangeville/Idaho

bohleber wrote:

6'

A slider is meant for close-up work!!!

bohleber Loc: southern Indiana

Thank you RWR

rfmaude41 Loc: Lancaster, Texas (DFW area)

bohleber wrote:

RWilson, Even with the lens 6" from the subject, the focus stays the same from end to end????

6 Feet, not inches, he says.