To experiment with ring flash, I bought a cheap Canon compatible LED ring flash from Wish. It works very well except there is an interference pattern picked up by the camera. This is most noticeable when taking video or when using the built in Canon focus stacking. Can anyone recommend a reasonably priced ring flash that wouldn't have this issue? David
Here is one extracted from a focus stack. You can see the banding. The background is actually a sheet of grey card.
Does not appear to be interference being picked up by the sensor, the primary issue I see is there are from what it looks like to me 3 lighting sources, one from left, right, i assume your ring flash head on pointed at the subject you can see a shadow s going in 3 directions and the lighting from the side and above mixed with the ring flash is likely creating the banding on the paper, are you using a shoftbox or any sort of diffusion to eliminate much of these lighting affects? Make sure to shut off the rest of the lighting and only use what you intend to light with and control in the scene, multiple light sources will only cause issues. Soft box and turning up the exposure will get you 90% of the way there, your ring flash is not even high enough on exposure to soften the shadows from the other lighting sources.
What kind of lighting are you looking for? I don't use a ring flash but I can get most lighting done with two triggered flashes off camera and a soft box. Here you can see a few images I threw together on black fabric, and you can see the light has a gradient to it even here too as the fabric rolls up the back of the tent. I guess a point I would call out here is that paper is highly reflective and so is some fabric (more than others) so they will reflect light back very quickly if not handled properly. Black background is a dust nightmare for spotting, white is easiest to wash out with extra lighting/exposure.
I tried again with only the ring flash and still got banding. I was happy with the existing lighting using the four LED strips but they didn't give me any light on the front of the models. hence the ring flash. Maybe I should just go to a standard flash gun with, maybe, a filter on the head?
David, your ring flash is a single source light, being in a ring I think produces the shadow effect you are experiencing, now if you were to place some curtain material around the flash ( leaving a hole in the center for the lens to see through) or something similar, this would create a multi light source or in layman's terms a much softer light thus removing the harsh shadow which create the banding. another way would be to attach a piece of thin whit paper in the shape of a donuts over the flash, you would still get the lighting effect, hopefully with out the banding, again this would produce a multi point light source.
To be honest an LED ringflash is pretty much a waste of money, they aren't really a flash as most of them just give a continuous light and the few that do give a flash have such a long flash duration with a low light output that they are not really much use for anything. The banding you are getting (particularly in video) is caused by the fact that the LEDs are being pulsed on and off by the controller within the flashgun circuitry, the camera can see this pulsing even though it is too fast for you to see. If you want a ringflash then get a proper one with an xenon tube and not LED.
We have had problems replacing 50w halogen lights with 5w LED in the ceiling in that the lights have been flickering so we have had to change the power supplies. I guess it is the same issue. I sort of guessed that this was the problem. Can you suggest a suitable ring flash?
Hi Dave, while we see if Ray has a thought on a ring flash, my 2 cents are you can spring for a good one like the MR-14EX II for example, or build a much more versatile kit with that sort of money. For close to half the cost of the canon ring flash you can get a couple of canon speedlights used, and buy a few triggers / a controller from yongnuo. Those off camera flashes will be able to be used for multiple purposes where the ring flash cannot. And as you can see cross lighting like i did will not give the direct head on light and shadow behind that the ring flash will. I of course may be biased as I am comfortable with a few flashes off camera and they can be really powerful in a wide variety of uses.
A) I can't afford the MR-14EX II and B) I am taking photos of scale model aircraft at a local hobby club and have limited time to take all of the items on show. Setting up a multi flash setup is probably not possible. The nice xenon bulbed ring flash I saw on YouTube is 5 years ago and is no longer available and it seems that every ring flash that I can afford is LED based so I will have to ditch the idea and think again.
Diffusion will go a very long way here, even with problematic LED lighting, so if you are not using any diffusers in front of the light, or using a light tent (even a sheet would do) I think you should look at that. the light can bounce around in the tent or box and even out, and it removes harsh shadows depending on how close the light is to the wall of the tent if your shooting through the side. Have you watched any videos on using light boxes for product photography? Some examples on a budget I found with 5 min of digging.....Obviously you wont get the performance from a budget item than the higher end gear, as you found with you ring flash you already have. https://www.amazon.com/Photography,DUCLUS-Portable-Professional-Shooting-Backdrops/dp/B099Z94MQP/ref=sr_1_4?keywords=Photo+Light+Tent&qid=1639070719&sr=8-4 https://www.amazon.com/LimoStudio-P...words=Photo+Light+Tent&qid=1639070719&sr=8-19
following on from what Johnsey said, the softer light will give your models a more realistic appearance
In the cheaper price range there are: K & F Concept KF150 Yongnuo YN-14EX Kenro KFL201 +others all similar. These all have the advantage that they are a split ring where the 2 halves of the light can be adjusted separately to get a better lighting effect. Like all lighting setups a ring flash will not be suitable for all subjects and can sometimes give poor results especially with shiny surfaces and better results can often be obtained with an off camera lighting setup as has been mentioned above. I have used the K & F concept ringflash for a couple of years and found it to be excellent for most macro and close up shots.
banding: shutter speed, if you hold you camera directly at the light and look at ti through live view you can see it flicker, to avoid this lower the shutter speed till its gone, should be do able on a still object or use a non flicker light scores, sylvanian light led tubes don't flicker