Light Tent Photography Tips

[AAAndrew]

So, I got a gift certificate for Christmas and used it to buy my first light tent for taking photographs of pens and nibs.

 

I've tried to photograph these columns of reflectiveness before, but I can never quite get the lighting right, so I usually just cop out and use my iPhone and blame the crappy photograph on my tools.

 

So, I'm looking for help, especially with lighting, as well as trying to ensure as little distortion as possible. I'd like to take some real close-up shots of small steel dip nibs which can be reflective. I don't want hot spots or banana-shaped nibs.

 

I'm sure I'll experiment, but thought I'd at least ask those who take wonderful shots already and know so much more about photography to see if I can shorten that learning curve as much as possible.

 

I'm shooting with a Sony Alpha, and while I don't have a macro lens, I do have a nice 50 prime. I got both 30w CF daylight lights as well as 45W white LED lights to light up the tent. I got the brighter bulbs because I was afraid the Compact Fluorescent may not be bright enough to get a tiny nib in the middle of a 24" light tent.

 

I'm most concerned about hot spots and glare, more than shadows.

 

So, anything I should try or keep in mind as I play with my new toys (which are coming early next week)?

 

Thanks

[El Gordo]

I certainly also would like to see tips coming from pen enthusiasts. Note that there is already a wealth of information out there on websites / blogs / youtube etc focusing ( ) on jewels, cutlery, ... and macrophotography.

[snowbear]

Setting lights is all about angles. The light will reflect off a flat object at the complimentary angle of the light - so if the light is 45 degrees above and to the right, the "hot spot" reflection will be towards 45 degrees above and to the left. The trick is to get in between.

 

For painted surfaces (not unpainted metal), a circular polarizer can be used to reduce the reflections. It will decrease the light, so a tripod (even a cheap one) is better than nothing.

 

Look for the book "Light, Science and Magic." As far as the CFLs being too dim, if you have a tripod (a must), use a longer exposure/higher ISO.

[tmenyc]

I learned a huge proportion of what I know here...really helpful colleagues here at FPN. You're essentially doing product photography, not macro photography, and the info sources are different. Your LED should give you plenty of light, and the light tent should give you sufficient diffusion. Get one that is at least 30x30x30, so you have enough room to get your camera inside and have maneuvering space. Yes, the tripod is essential, to take shutter speed out of the equation. I've found that I need at least f-11 to get what I want, with my macro lens. Your normal lens may need a bit more, so need the tripod more. Everything else I do in Lightroom afterwards. Yes, the LSM book is good, make sure you get a recent version. Libraries should have it.

 

Tim

[Manalto]

Once you have the soft lighting to your liking, a subtle accent light placed inside the tent can give the image a little extra personality. I look forward to seeing your photos!

[christof]

Andrew,

 

1. I think if you really want to photograph nibs only, you'll need macro lenses.

 

2. There will be reflections on shiny metal surfaces. I don't know reasonable ways to avoid them (after 10 years of active research in object photography).

 

 

 

C.

Edited January 13, 2016 by christof

[tmenyc]

AA,

following on Christof's post, and the consistently outstanding quality of Christof's work is my goal and what got me started in this -- the key is clearly in managing reflected light. If you get too close you'll see the camera or tripod on the nib; too bright and it's all glare unless you are pointing the light into an umbrella or are really super-diffusing it. I've actually taken better nib shots with my cell phone but a big part of that is luck, not method.

 

Tim

[AAAndrew]

Thanks for the suggestions. I suspect a lot of it will be trial and error. A lot of the nibs I want to photograph are a dull grey so reflections will be less of an issue than even light to see the imprint. Others are much shinier and will pose other issues.

 

I'm wondering about using a tripod set back but zooming in with a longer lens? Would that flatten the image a bit? I'm not sure that that wouldn't be good thing. What about prime lenses? Their clarity is better, but is there distortion when trying to get in really close?

 

I also want more depth of focus which requires a bigger f-stop, so obviously a tripod and remote or timed shutter release is important.

 

The rest seems to be a matter of playing with lights to optimize hot spots, and ensuring the object is on a plane parallel to the plane of the camera if I don't want any banana-shaped pens. Am I getting that about right?

[Manalto]

I'm wondering about using a tripod set back but zooming in with a longer lens?

 

All other things being equal, the higher the magnification, the shallower the depth of field.

 

One technique I used a lot was a large foam-core board covered in matte black with a hole cut out for the lens. This eliminates reflected images of camera and photographer. It can be placed on a stand, but I usually set up my shot and then just hung it on the lens itself, foam-core being the light stuff that it is. Of course, your reflection will be black - or you can use the white board plain, but the "dot" where the lens pokes through may be apparent (and distracting) in mirror-like surfaces. You'd be better off having a controlled black reflection in the vast sea of white that your tent provides for the mirror surfaces and then using the other side of the foam-core when you want bounce fill.

Edited January 13, 2016 by Manalto

[tmenyc]

Manalto,

great idea; I'll give it a try.

 

AAA -- as Manalto says, longer lenses bring the subject forward but the depth of field loss is huge. Tried it. If you have a truly great normal lens it might be OK, but I don't. And, I use one of Canon's little wireless shutters, works like a charm on my Canon SL1. It has turned even family event photography into a laugher too, since all that gathering into a timed shot rapidly goes by the boards when I'm standing in the shot pushing the remote button at will...we used to get everyone but the dog to hold still, now I get the dog when I want but everyone else is moving. Much better, all in all.

 

Tim

Edited January 13, 2016 by tmenyc

[christof]

 

 

One technique I used a lot was a large foam-core board covered in matte black with a hole cut out for the lens. This eliminates reflected images of camera and photographer.

 

I use a simple reflector in the way you describe. It's white and helps to bring some direct but diffused light to the object in sens of the direction of view.

 

 

On the cap top of the Pelikan 112 (right side on the picture) I used photoshop to eliminate the reflected picture of my camera, but on the clip, it's still visible...

But I don't think that this will be a problem when photographing steel nibs. But the light reflections will stay. As already said, I don't know a way to avoid them.

 

C.

 

PS: The lens I use is a Micro Nikkor 55/2.8. On a D80 it's like 80mm lens.

Edited January 13, 2016 by christof

[Manalto]

Christof,

Your reflector does a beautiful job of bringing out the detail in the foreground and the reflections of your camera in the clips are in no way obtrusive. In fact. they help define the shape of the bend of the clip (particularly in the pen on the right), a detail that could get lost in poor-quality reproduction or on an inferior monitor. I have no experience photographing pens but wonder if sometimes the deliberate introduction of a black (or a range of grays?) reflection might be useful in cases such as this, to more clearly define shape.

 

For my close-up (non-pen) photography, I've used the lenses you mention in your PS with satisfactory results. ETA correction: My digital macro lens is a 60 mm.

Edited January 13, 2016 by Manalto

[jmccarty3]

Does it make any difference if the macro lens is 60 mm or 100 mm?

[Manalto]

You sacrifice depth-of-field with the longer (100) lens, so you'll have to stop down (use a smaller f-stop) to compensate. Also, the longer lens distorts perspective somewhat, just as a wide-angle (fisheye) distorts in the opposite manner. It's not a bad thing and can be put to artistic advantage in the right hands.

[bogiesan]

The best tip I got from a professional product photographer:

When using a white tent to shoot shiny stuff, use a piece of white foam core in front of the camera. The lens becomes a tiny black spot instead of a large black rectangle. However, Steve's experience was vast and he knew when a black (or gray, red, yellow, blue, or even polished stainless steel) camera shield was appropriate for the subject or the image he was creating.

 

Steve and I are old school digital shooters. We use Lightroom for cataloging and minor tweaks but we set up the shoot so the image that is captured when the shutter clicks is exactly what we deliver.

[bobje]

David Hobby's The Strobist website offers some useful and inexpensive tools. This cardboard box light tent works well.

http://strobist.blogspot.com/2006/07/how-to-diy-10-macro-photo-studio.html