FAQs about Dental and Intraoral Photography
These are frequently asked questions regarding intraoral photography at dental clinics, the MF18 ring flash, and our "Omakase Mente" maintenance service.
About Photography
Q. Why is a ring flash used for intraoral photography?
A. Primarily for the following five reasons:
- The ring-shaped discharge tube is positioned near the lens, making it easy to illuminate even the back teeth.
- The powerful strobe allows for sufficient brightness even when the aperture is stopped down (F22–25) to keep everything from the front teeth to the molars in focus.
- It minimizes the influence of ambient room lighting and reflections.
- Its high color rendering index (Ra96) ensures natural color reproduction.
- The flash duration is extremely short (1/thousands of a second), which prevents camera shake and subject motion blur.
For more details, please see How to take intraoral photos.
Q. What is the difference between a twin flash and a ring flash?
A. Each has its pros and cons. A ring flash is excellent for illuminating narrow spaces, but reflections can be more noticeable when photographing flat surfaces. A twin flash is less prone to reflections because the light strikes from an angle, but it is not as effective at illuminating narrow areas.
With the MF18 II, using the separately sold MF-PL Cross Polarizing Filter Set allows you to reduce glare on the tooth surface even with a ring flash.
Q. What camera and lens do you recommend for intraoral photography?
A. We recommend the Nikon D3500 or D5600 paired with an AF-S DX Micro NIKKOR 85mm f/3.5G ED VR or Tamron SP 90mm F/2.8 Di MACRO 1:1 VC USD lens (as these are discontinued, you will need to purchase them secondhand). If using mirrorless Z 50 or Z 30 cameras, please attach these lenses via the FTZ II mount adapter.
If sourcing the camera and lens proves difficult, you may also use our Omakase Mente (Intraoral Photography Kit), which includes a complete set.
Q. Can you teach me how to take the photos?
A. Please refer to our tutorial video (5-view method) and our web-based guides: Part 1 and Part 2.
Q. Can I use the MF18 / MF18 II with my existing camera?
A. Please check the Camera Compatibility Chart.
Troubleshooting
Q. My MF18 won't flash or isn't flashing properly. Is it broken?
A. First, please try 1. Resetting the device and 2. Cleaning the hot shoe. If the issue persists, please request a repair.
※If you request a repair without having tried resetting or cleaning, and the issue is resolved by us performing these tasks, we will charge a service fee regardless of warranty status.
| Symptom | Action |
|---|---|
| Pilot lamp does not light up / stays red / takes a long time to turn green | Replace all four batteries with new alkaline or fully charged NiMH batteries |
| Flashes when pressing the pilot lamp but not when pressing the shutter | Check the mounting, perform a reset, and clean the hot shoe |
| Does not flash even when pressing the pilot lamp | If it does not flash after a reset, request a repair |
| Flashes intermittently when moving the coiled cord | Possible wire breakage; request a repair |
| Only one side (A or B) of the flash head fires | If it does not fix after a reset, request a repair |
| Photos are dark / brightness varies / images are pure white regardless of settings | Reset and clean hot shoe; if no improvement, request a repair |
| Popping sounds / abnormal noise, odor, or overheating | Remove batteries immediately and request a repair |
※The MF18 is not hermetically sealed; dust entering the flash head may scorch due to heat, occasionally causing a faint odor like burning paper. If you hear a "popping" sound or notice smoke, strange odors, or abnormal heat, remove the batteries immediately.
Q. How do I reset the MF18?
A. You can reset it using one of the following two methods:
- Method 1: Turn on the power, use the Set button to return to the main menu, and go to the wrench icon (SETTING) in the bottom right. On the second page, select "Reset," press right on the cross-key, and press the Set button to complete the reset.
- Method 2: Turn on the power, and while in the shooting-ready state, press and hold the Set button for about 10 seconds. The modeling light may turn on (or off) during this time, but continue holding the button. Once the display changes to a green "A" (Full Auto), the process is complete.
About Omakase Mente
Q. What are the payment methods?
A. You will need to register a credit card. Please contact us if this is difficult.
Q. Is there a minimum contract period?
A. Yes, two months.
Q. What should I do if something breaks?
A. Select "Equipment Replacement" on the Omakase Mente form. We will ship a replacement unit immediately.
Q. How do I handle a malfunction of the rented ring flash?
A. Please apply via the "Equipment Replacement" section on the Omakase Mente form, and we will ship a replacement ring flash.
- Check that the replacement unit works correctly once it arrives.
- If there are no issues, place the faulty ring flash in the black case the replacement arrived in, attach the enclosed shipping label (Yamato Transport, freight collect), and send it back.
Only return the ring flash unit itself. Do not include the adapter ring or AA batteries; keep those with you. If the replacement unit also does not work, please contact us before returning it.
Q. Is a USB cable for data transfer included with the camera rental set?
A. As we expect data to be transferred via an SD card reader, no USB cable is included with the rental set. If you wish to provide your own cable, the Nikon "UC-E20 USB Cable" is compatible if the rental camera is a Nikon D3400. Since the official product is discontinued, you can find compatible alternatives by searching for "UC-E20" on e-commerce sites.
Q. I haven't received the Square invoice (email for card registration).
A. We can resend the initial Square invoice (which also serves as credit card registration). The sender address is invoicing@messaging.squareup.com. If you cannot find the email, please check your spam folder and ensure your settings allow receipt of emails from "@squareup.com." Once credit card information is registered during the first payment, subsequent monthly fees will be charged to the registered card automatically. If you still cannot confirm receipt after we resend it, please contact us.
For other matters, please visit the Omakase Mente page.
If the issue is not resolved
Please contact us via the inquiry form (select "Dental Clinic / Medical Institution") or by phone (03-4455-3057 / Weekdays 10:15–12:00, 13:00–16:45).