How to improve results of smooth subject

[John Mulvihill]

Hi,
New to this and using 3DF Zephyr Free.

My subject is a roadracing go-kart which is mostly a smooth, shiny, monochrome white fiberglass surface.
When I export the finished model it is pretty lumpy. I understand that the surface works against me.

The kart is roughly the size of a refrigerator turned on its back. The mechanical pieces come out well with accurate detail. No problem taking detailed photographs by moving in a circle with a monopod on the camera.

Covering the body with dust or dirt, or using a projection system is a no-go, especially since I have to go to the race track to take the photos.

If I use a narrow, dark painter's tape to create a graph paper like pattern on the surface, or a couple hundred tape dots on the bodywork would that accomplish the same?

The painter's tape would help clarify the curves and planes of the body's surface.

Any other suggestions or thoughts?

Thanks,
John

[cam3d]

Hi John Mulvihill - It's a shame you can't powder/dust the surface because that really will give you much smoother results.

Dots on the bodywork might help a bit, but you really want LOADS of feature points. Painters tape wouldn't hurt.

If you share some of your photographs with us we can give you more feedback re: camera settings.

[John Mulvihill]

Thanks Cam
i'll do that in the next couple days when I can get to wifi.
Just the original photos?

Much appreciated
John

[cam3d]

If we can get the ZEP file as well (Zephyr project file) that might help a bit, but really I only need the photos you're feeding into Zephyr!

[John Mulvihill]

[cam3d]

Hi again John Mulvihill

Thanks for sending those through - There isn't any metadata associated with those images so I don't know what kind of settings you are using, but I can give some generic advice:

- If you're not already, use a tripod instead of handheld, and ideally a remote shutter cable so you don't accidentally blur your images with vibrations from taking the photo.
- Shoot with a higher F/stop (F11 or higher) for a wider DOF, and compensate for the lack of light with extended shutter speed. ISO as low as possible.
- The floor is great, loads of features to aide matching
- All of the above is an uphill battle again the feature-poor surface, without increasing the features on the surface you're always going to get sub-par results. If you're feeling creative you can do some scan cleanup in a program like meshmixer.

Hopefully, this is somewhat helpful.

[John Mulvihill]

Hi Cam,

Any input is a big help and moves me (and others) forward.
To get the photos, I had to use a Nikon Coolpix L22 camera set on automatic. One of the joys of flying on a cheap airline and avoiding $$$ extra baggage charges.

Next time , I'll use my Nikon D90 dslr on manual settings (Thank you) after applying 1/4" painters tape in a criss-cross pattern.

The lower rocker panels and the nose curve under and that edge was very irregular. Would it help to get the kart up off of the ground with some blocks?

Thanks for the input.
John

[cam3d]

John Mulvihill No problem! Glad to be of service - I would definitely recommend raising the kart off the ground with some blocks to allow easier access to lower viewing angles. I hope you see an improvement the next time you photograph the kart, if you have any more questions at all, I'm more than happy to help where I can.