Struggling with LED lamps and DOF...

[epatsellis]

Would you mind giving your opinion on this setup please? seems to good to be true - the price isnt the most important thing for the company but i was also considering this one for my own use at home for ebay photos etc....
https://www.amazon.co.uk/Neewer-Pro...1_3?ie=UTF8&psc=1&refRID=YRXZJQR2TSFNXFVCXX4V

Just be aware I think those give a blueish color so you'll have to deal with customizing your white balance.

Good to know; colour-casting is a definite problem with lower-end gear, but it's generally easily fixed in post. As for the output, 250w/s is plenty for the work you're doing. I often do 2-3 light full-body portraits using only a single 200 w/s power pack.

Maybe, maybe not...

As a point of reference, for product work I start with 1600 w/s pack and a single head in a large softbox, it's not unusual for me to have to use a double head and two packs to get enough light on set at times. Target aperture for a small camera (e.g. 35mm and smaller) is ~f11 to f16. One of the best lenses that is inexpensive for this would be a 55 f2.8 or f3.5 Micro-Nikkor. I prefer a much longer lens for product work, on 4x5 I use a 210-300mm lens (480-600mm on 8x10), so on 35mm, that's be close to 90-100mm, there is less geometric distortion, more working room for flags, etc. Ditch the zoom lens, use a fixed focus lens, good tripod (or camera stand which is preferable, I use a fully kitted Cambo UST personally, Bogen makes a small stand as well) While you don't need a shooting table, they can help immensely when shooting many items.

Long objects aren't impossible to shoot and keep in focus, this is a 3 1/2 foot wide hydrostatic lawn mower transmission:

In this case, I shot with a Sinar view camera, lots of swing and a scan back with continuous HMI lighting, but the same basic concepts can be used with a small camera if you're willing to learn. (this was a test shot to determine scale and exposure, hence the marks on the left axle that haven't been cleaned off yet, and the final image is quite a bit brighter)

In my studio, high key shooting requires lots of light, high DOF requires small apertures which will require lots of light. A softbox 2-3x the size of the object you're shooting should result in a shadowless background if propped up 1/2 to 1" off the table. Best bet for a background is matte white Formica or any similar laminate. Fill cards and flags as needed to model the shape of the object. Cleanliness is essential, when it looks absolutely spotless, clean it once more. For plastic items, dryer sheets work well for dissipating static charges. I'd ditch the "tent" or "cube" or whatever they're called these days. If you want to control light and image values, throwing light everywhere isn't the way to do it.

What is the purpose of the DOF calculator, exactly? In my experience it's one more thing that you'll spend way too much time on and never have it "click". Put the phone down and spend some time learning, it will serve you better in the long run.

Each image on the computer should be obvious what your DOF is, and if there is an adjustment to be made. (you are shooting tethered and proofing on a larger monitor, right????)

There's a simple way to fix color cast in shadows, btw, eliminate all other sources of light. Stray light will impact color balance in the shadows first.

 

[Mr_Chris]

Thanks epatsellis! thats a lot of helpful info!! Your setup/equipment is mind-boggling....i hope i can get to a stage one day where i can justify/afford all that lovely kit!
As it turns out my management changed their minds again and now we've ended up with a green-screen setup - which im finding quite challenging!
Heres the setup with 4 x 500W LED Lamps - 2 have been sent back and we are 'upgrading' to a set of 4 x 1000W LED's - turns out LED's dont throw much light out so they need to be powerful - and a few of them!

We are finding that the green screen is throwing a lot of light back onto the subject and giving us extra work in Photoshop to remove green 'halos' and colour spill - even after moving the subject further away from the screen and turning the lights down....anyone have any suggestions please? (no swearing please, i know most photogs hate green screens!)

 

[cnoevl21]

I'd try moving the camera back and zoom in. also, if your end result is a blue background, why not just use a blue background? White on white is such a major pain in the ass

 

[Mr_Chris]

So the move to 1000w made quite a big difference - so did moving the green screen further back and also moving the camera back and zooming in at 45mm. We are fairly happy with the final outcome now but have found that white card scrims still need to be held in the right position to create necessary fill light at times - or give reflections to chrome parts. Personally i wouldnt go down the road of LED lighting for Product Photography again (this was a company decision due to fear of fire risk) as i found the light being produced too limited and too much of a torch beam effect as opposed to a nice blanket of light. Some people recommend LED's for close-up work such as jewellery but using them close up causes other problems such as the LED bulbs themselves being reflected in the product - and diffusing the light can be tricky with a flat panel!

I would like to thank you all for your help and guidance in this matter and it would great if the mods could leave this post up in case it could help others - searching for help with Green Screens or LED's dosnt seem to yield many results - on this forum especially