Continuous Light Option

[CIC]

Hello friends and fellow photographers

I was wondering whether cheap LED bulbs of 28W (cost around $4 in my country) can be a good cost-effective solution for small product photography, provided a large white diffuser is used in front of the light bulb? If possible, this should provide an excellent and easy WYSIWYG solution.

Hopefully experienced members can shed some light on this idea.

Thank you all.

[pschlute]

Hopefully experienced members can shed some light on this idea.

I will attempt to enlighten you

The problem with many lights not intended for photographic use is they do not emit a continuous light. Although the human eye sees it as continuous, the cameras shutter speed will show that they are in fact pulsed light. If you use a slow enough shutter speed you may be ok. The thing to do is give it a try.

The other issue is white balance. I suggest you use raw and adjust the WB in post.

[CIC]

I will attempt to enlighten you

The problem with many lights not intended for photographic use is they do not emit a continuous light. Although the human eye sees it as continuous, the cameras shutter speed will show that they are in fact pulsed light. If you use a slow enough shutter speed you may be ok. The thing to do is give it a try.

The other issue is white balance. I suggest you use raw and adjust the WB in post.

Thank you for your reply.

I am thinking of using shutter speed <=1/100. You are right to point to the flicker issue. I hope a low shutter speed such as I mentioned should be enough to reduce the flicker.

I have checked with some available lights having 1900lm~2000lm as the brightness value and 6500K as the declared colour temperature.

Please share your thoughts.

[DanK]

In my experience, the drawback of LEDs isn't primarily flicker. They can flicker if attached to the wrong kind of dimmer, or if they are not dimmable bulbs and are put on a dimmer anyway. But in my experience, at full power, LEDs don't flicker in the way that fluorescent bulbs to.

However, LEDs do have a big issue: inexpensive LEDs often have irregular color spectrums, with big spikes and gaps. This can't be corrected with a simple white balance adjustment. In addition, if you are going to dim them, many LEDs show a change in color spectrum as they dim. I have a lot of them in my house that produce an awful yellow-green cast if dimmed a lot.

There are LEDs that have good spectral distributions, but they tend to be expensive. Here in the US, they can be several times the cost of cheap bulbs.

You should look for two numbers. The first is commonly avaiable: CRI, which stands for Color Rendering Index. Good bulbs are at least CRI=90; excellent ones are 95 or more. However, CRI does not include reds, and it's common to find relatively inexpensive LEDs with good CRI numbers but weak reds. The best bulbs will specify at least one red, usually R9. That too should be at least 90. It's often as low as 50 (the minimum legal requirement in at least one US state) in inexpensive bulbs that advertise a high CRI number.

At $4 each, I doubt these are very good. However, I would check to see if the manufacturer documents these numbers.

[xpatUSA]

I am thinking of using shutter speed <=1/100. You are right to point to the flicker issue. I hope a low shutter speed such as I mentioned should be enough to reduce the flicker.

Srijan namashkar,

They may be difficult to find in Bharat - but LEDs with a smooth built-in AC-DC regulator get around the flicker issue.

I have checked with some available lights having 1900lm~2000lm as the brightness value and 6500K as the declared colour temperature.

I use two 30-degree 3500K LED floods and two movable homemade tracing paper diffusers:



Anticipating howls of dismay about 3500K from others, my 6500K models had a big blue spike in their spectrum.



The 3500K is much better:



Custom WB works well enough for me with that lighting.

[Manfred M]

Just to keep things interesting. CRI was primarily developed for determining the colours produced by fluorescent lights. This is not particularly good for LED light sources, a new approach was proposed a few years back: IES TM-30-15

It is not in widespread use yet, but it makes for an interesting read: https://www.energy.gov/sites/prod/fi...fact-sheet.pdf

[xpatUSA]

Just to keep things interesting. CRI was primarily developed for determining the colours produced by fluorescent lights. This is not particularly good for LED light sources, a new approach was proposed a few years back: IES TM-30-15

It is not in widespread use yet, but it makes for an interesting read: https://www.energy.gov/sites/prod/fi...fact-sheet.pdf

Interesting indeed, thank you!

By coincidence, page 5 graphs were done based on 3500K - same as my bench-top floods.

Another coincidence: It uses CIECAM02 which I just did here:

https://www.dpreview.com/forums/post/66074685

LOL

[DanK]

Just to keep things interesting. CRI was primarily developed for determining the colours produced by fluorescent lights. This is not particularly good for LED light sources, a new approach was proposed a few years back: IES TM-30-15

It is not in widespread use yet, but it makes for an interesting read: https://www.energy.gov/sites/prod/fi...fact-sheet.pdf

I was told that the fluorescent manufacturers wanted the reds omitted because it was so difficult for them to produce them.

You can find the IES TM standard referenced for some high-end bulbs. For example, here are the stats for the Soraa Vivid BR30s that I use where color matters:

CRI 95
R9 95
TM30 metrics: Rf 90, Rfh1 90
Whiteness: Rw 100

However, at US prices, these now run $19 or more each.

[xpatUSA]

I had a vague memory of fluorescent lamp phosphors being tuned to get a better CRI. After a quick search:

"“Tuning” the Spectrum for High CRI
Over the years, fluorescent phosphors have been tuned and refined to render those eight
color samples well, i.e., very much like the incandescent or daylight references. But look at
the “spikes” in the spectral power distribution (SPD) for the fluorescent source in Figure 1
below. If the phosphors were changed just slightly, shifting the emission wavelengths, the
CRI score may drop significantly, but with little change in color rendering as perceived
by the human eye."

https://www.energystar.gov/ia/partne....pdf?0b55-1475

Spectra as spiky as ever, though!

And they're still at it with LEDs and other stuff:

https://pubs.acs.org/doi/10.1021/cen-09646-cover

[CIC]

Thank you all.

I am trying to set up a small home studio to taste the market which is not as mature as the first world countries. Moreover, the costs are very high when it comes to photography equipment and payments may not be forthcoming from the very beginning.
Renting this equipment or a studio is not much of an option too, mainly when I am in need to create a portfolio first.
I understand that the path is steep but I do hope to scale that with the help of the fellow photographers like you.

For me, the two main issues that I need to sort out to start with my home studio are- 1. Basic lighting equipment (including a small diffuser/softbox) and 2. A portable(and foldable) workbench/table.

Any suggestions/ advice in this context would be highly appreciated.

Thank you all again.

[Manfred M]

I work on the fine art side of still life photography, rather than the product photography side, so my needs are a little bit different than yours. I do my work as a hobby; the end market for product photography where money can be made is saturated and clients expect the photographer to be using the high end gear for cameras, lenses, lights, etc.

The ones that have made it into the business started off as assistants to the established product photographers. They learned their skills by working with them and got their contacts and names known in the industry that way.

You need two other skills to be successful; set design and set dressing. So as well as the photography studio, you need a place to build and paint the sets and backgrounds as well as having a small warehouse of props that can be used as parts of the settings for the product.

The good news is that for most product photography, you don't need a huge space as a studio. but that still does not mean any small space will do. To make life simple, you need a room with neutral walls, otherwise the light bouncing off the walls and ceilings will have a colour cast that can be hard to manage. You also need a fairly high ceiling so that you can place your lights over your products for those "birds eye" shots. The ceiling has to be high enough that you can place the light and the diffusers over the set and still have enough height for the camera. You will need light stands and at least one heavy duty light stand with a boom.

In terms of lights, you will probably need at least five to start with. For example, to photograph a glass of sparkling water, you need to have a light to light the liquid from the left side and the right side, two more lights to light the glass from the left side and the right side as well as a light just to light up the bubbles.

A very sturdy tripod that can be equipped with a horizontal attachment is required. If you are successful, a camera stand, rather than a tripod is something to think about (hint: these are very expensive), but they let you get the work done in a fraction of the time. A ball head is not the best solution for this type of work; I use a geared head on my tripod so that I can do fine and accurate adjustments needed for this type of work.

You will need to shoot tethered, so a computer with cable to connect to your camera is needed. The is far more effective than looking at the images on the camera's screen and really speeds up the workflow and image quality.

I know that you are looking at inexpensive LED lights. I don't use them for a number of reasons, mostly because of the limited light that they put out, which makes hand-holding impossible) and that good ones, that produce a good colour response, are very expensive. The fact that I already own studio flash that I use for portraiture means I can stick with existing gear and the only thing that changes is the size of my light modifiers. The high and variable power output are very useful to me, as are the modelling lights which let you see how the shadows will fall and where the reflections are.

You will also have to invest in scrims, gobos, reflectors and flags to shape the light Grip gear to hold the equipment, lights, etc. I have a number of superclamps, grip arms, grip heads, baby plates, baby pins, etc. as well to support the modifiers and the subject.

Finally, you need to be very good at Photoshop (not Lightroom) because the final output will require a lot of work in post. Being able to cut out and isolate different parts of the set is critical to getting a good quality final image.

I hope this all makes sense to you. Product photography is probably the most difficult and challenging type of commercial photography. I suspect that is why you see so many people doing portraits and weddings.

P.S. I have formally studied still life photography; during studio lighting courses at the local college and at the local photography school. Two of these courses were general studio lighting courses with significant still life elements and two were 100% still life courses. On top of that, I also attended three food or still life workshops.

The photographer I studied under most recently is an internationally known "A-list" photographer (just look at his client list); his website is:

http://www.adrienduey.com/

[xpatUSA]

... For me, the two main issues that I need to sort out to start with my home studio are:- 1. Basic lighting equipment (including a small diffuser/softbox) and ...

On the subject of diffusion, I would say "large", not "small". The smaller a diffuser relative to an object is, the less the effect of even lighting (from a diffuser's Lambertian surface) upon an object is and the more the Inverse Square Law applies.

More about those here:
https://kronometric.org/phot/lighting/lighting%20handbook.pdf

Experiment with relative distances between lamp, diffuser and object. Also be aware of the relationship between diffuser size and object size - smaller objects need less diffuser area.

Please note that this advice is only about diffusion: Manfred and Dan have already covered everything else.

By way of encouragement, here's a shot intended for ebay using the simple two-lamp setup that I posted earlier:



I hope that this helps!

[DanK]

Srijan,

A more inexpensive option is to use halogen flood lights. The are very cheap (at least here), and they have a reasonable spectral distribution. If you dim them a lot, the color shifts, but I've found that this is usually manageable.

I don't do product photography, but I do a lot of close-up and macro images of flowers, which have a lot in common with product photography. If you look at the flower photographs on my site, the vast majority were illuminated by two halogen lights held in "hair light" fixtures, like this: https://www.bhphotovideo.com/c/produ...Mini_Boom.html.

Although Manfred says you need at least 5 lights, almost all of these photos were taken with only two, usually one direct but with a diffuser in front and one indirect, reflected off an umbrella.

The only disadvantage of halogens--or the expensive LEDs I mentioned above--is that they are not bright, and you therefore need very slow shutter speeds. That in turn requires a stable surface. A heavy table on a concrete floor is perfect. I use a heavy table on a wood floor, and I have to be careful about vibration.

I don't have a softbox. I use two sheets of baking parchment paper for a diffuser.

I don't shoot tethered.

Here is an example of a setup I used some years ago for flowers. Ignore the stuff piled on the table--I use that when I'm not holding the flower in a clamp.



I agree with Manfred that a horizontal boom for your tripod would be ideal, and I've been thinking about buying one. However, you can often make do without one if you have to, for example:



I don't own scrims, gobos, reflectors or flags, but I intend to get some of this sort of equipment. In particular, flags or snoots would be helpful to avoid light spilling into areas I don't want.

All in all, my suggestions is to start small and only add more equipment as you need it. You will need a tripod, a good head, and something to hold at least two lights. You will need a white or neutral card to fix white balance. You'll need some way to diffuse your lights, and you will probably want at least one of them on a dimmer. You'll need a work surface and background that are ideally close to the color you want. A geared head is much superior and will save you a lot of time, but I've done this work with a ball head as well.

The big tradeoff in this is continuous lighting vs. strobes. I started with continuous lighting because it is simple and inexpensive and because it makes it easier to visualize the lighting. I can get much of the adjustment of the lighting done without test images--hence, less reason to shoot tethered. The main disadvantage is the slow shutter speeds and all that comes with it.

Dan

[Manfred M]

One additional comment on Dan's use of hot lights. Scrims and reflectors melt and / or burn if you get them too close. I know more than one photographer who has managed to do that.

[DanK]

One additional comment on Dan's use of hot lights. Scrims and reflectors melt and / or burn if you get them too close. I know more than one photographer who has managed to do that.

An important point. In the cheap hair lights I use, the distance from the front of the halogen bulb to the rim is only about 2cm.

The baking parchment paper sold here is usually rated as safe to between 215 and 260 Celsius, which is more than enough for those particular bulbs. I would worry with stronger halogen or incandescent bulbs. LEDs are far cooler.

[CIC]

Thank you, Manfred, Ted and Dan for your time and help.
Namashkar Ted

I am going to give the LEDs a try and post the result here. Please let me know your thoughts.
I also have two old flashes- an SB600 and a Simpex (completely manual with no option to control the output but to use the inverse square law). Should I give this combo a try? Kindly suggest some basic softboxes for these flashes (if these can be used at all). I would post the result with these too (if can be used) so that you can compare and share your valuable thoughts.

Thank you all again. Dhanyobad Ted.