[oralsurgery]

Staff note: This post may contain affiliate links, which means Pentax Forums may earn a small commission if a visitor clicks through and makes a purchase. If you would like to support the forum directly, you may also make a donation here.

---

Hello All,

New to the forum and was reading some back threads re: use of Pentax DSLR for dental photography. I am an oral surgeon looking to add a nice camera set-up to my busy practice. I am ideally looking for a setup that would be able to take intraoral shots (pictures in the dark hole that is the mouth) and portrait shots.

I know that I will @ minimum need 1-2 macro lenses, a ring-flash unit and a camera. The threads on this subject are a bit dated and I was wondering if anyone has helped a dental professional get setup with a camera like this. Ideally the camera would be easy to use / relatively light weight in case I'm so busy that my assistants need to be taking the pictures.

Best,
OMFS - Surgeon

[pathdoc]

You should talk to @pathdoc, who is a pathologist who uses a similar setup.

Speak of the Devil and he appears.

Welcome, OP.

The threads may be dated, but the basic principles of photography never change.

At one stage Pentax had a 100mm macro lens and accessories specifically set up for dentistry work: SMC Pentax-A Dental Macro 1:4 100mm (for legacy fanatics): Micro Four Thirds Talk Forum: Digital Photography Review or SMC Pentax-A Dental Macro 100/4.0 – B I T Z

The current Pentax 100mm macro lens (the 100/2.8 WR) has the ability to do 1:1 reproduction without the use of close-up lenses, and both OEM and third-party ring flashes are available. I initially bought one of these to use in my anatomical pathology work, but had to transition to a 35mm when I found the field of view too narrow for forensic autopsy (whole body) and close-up large specimen work. These are not handicaps I would anticipate you facing, and given that one of the design purposes behind a 100mm macro is to photograph wet and slimy things at a significant remove from the lens (mostly frogs, insects, etc. in the field), it might be ideal for your intra-oral work, especially towards the rear molars and everything posterior.

The Pentax units are either analogue TTL protocol (e.g. the AF080C) and require older digital cameras - *istD, *istDS, *istDS2, all long-out-of-production - to get the best out of them, and for the more modern bodies are quite expensive (AF160C), but you may be in a position to absorb that as a business cost. Any of the currently available or some more recently superceded Pentax digital bodies will suit you down to the ground and are not hard to operate, and you don't have to break the bank in order to get a good one. They will all be fine, especially if they're being used in the relatively easy-wearing setting of a medical practice, and the in-body image stabilisation should help you get crisp, clean shots.

I haven't actually used the AF160C ring flash so I can't speak as to its utility, but perhaps someone who has can chime in at this point and let you know the ups and downs.

[oralsurgery]

Hello All,

New to the forum and was reading some back threads re: use of Pentax DSLR for dental photography. I am an oral surgeon looking to add a nice camera set-up to my busy practice. I am ideally looking for a setup that would be able to take intraoral shots (pictures in the dark hole that is the mouth) and portrait shots.

I know that I will @ minimum need 1-2 macro lenses, a ring-flash unit and a camera. The threads on this subject are a bit dated and I was wondering if anyone has helped a dental professional get setup with a camera like this. Ideally the camera would be easy to use / relatively light weight in case I'm so busy that my assistants need to be taking the pictures.

Best,
OMFS - Surgeon

Thanks for the advice, what a friendly forum!

I think the component that I have the most questions about is actually the ring flash. I don't think the Pentax AF160FC is still in production and I'm not sure of the usage life on a used unit. If anyone has any experience with either this flash or 3rd party units any advice would be greatly appreciated.

Best,
OMFS - Surgeon

[TER-OR]

I use the Sunpak D8XR ring flash for insect macro work. I use it in manual mode, which should be fine for you. Once you get your conditions set, I doubt they'd change at all so you can just use manual pop on that flash.

[mikeSF]

not much to add here but I used to own a K-mount Vivitar 90mm macro lens that had an overlay decal/sticker on the barrel showing settings/markings for teeth. I peeled it off, but the owner said his dad was an oral surgeon and used the lens in his practice.

here's that one: https://www.pentaxforums.com/userreviews/vivitar-90mm-f2-8-macro.html

[Blacknight659]

50mm Macro: https://www.amazon.com/Pentax-SMCP-D-Samsung-Digital-Cameras/dp/B0002YE66S/r...tax+50mm+macro

100mm Macro : https://www.amazon.com/Pentax-100mm-Macro-Digital-Cameras/dp/B0030GGS3O/ref=...ax+100mm+macro

90mm Macro Tamron for Pentax : https://www.amazon.com/Tamron-AF-90mm-2-8-International/dp/B00022330A/ref=as...243dc856c08fd3

35mm Macro : https://www.amazon.com/Pentax-K-Mount-35-35mm-Cameras-Limited/dp/B00EZJPU48/...6c54ddaf51831a

The lenses above are easy to get a hold of and will do what you need. My uncle is a dentist and he used a Yashica Dental EYE camera similar to this one. It had a 100mm macro lens, but couldn't focus to infinity. It also had a built-in ring flash, but you will need to purchase one of those. I personally think the 100mm macro is your best bet or the tamron 90mm macro.

[mcgregni]

I have just recently completed a detailed overview of the AF 160 FC ringflash, as part of a new Supplement document for my 'Pentax Flash Guide'. This is really a guide to practical usage and operation, not any sort of field report.... but it is designed to help people thinking of getting the ringflash, so I am happy to post the text here for information, as it may help with the decision .....


TheAF 160 FC
(Circular ‘Ringflash’)

This type of flash unit is intended for close-up and macro photography, but is also often used for portrait and product photography applications. The advantage for very close subjects comes from two key aspects ; the lens to flash axis and the light source size in relation to the subject. The angle of view coverage is 60deg.

Type and Purpose
The Pentax‘Ringflash’ consists of two main parts connected by a cable. The light emitting part is a circular flash head containing 4 light tubes that attaches to the front of the lens with adaptor rings to allow for different size lens front elements. The other part is a control and power unit that attaches to the camera hotshoe, and includes the batteries and controls. The two are connected by a cable that passes both the power supply and flash output instructions tothe circular flash head. The flash is powered by 4 AA type batteries, and the maximum rated recycling is 7secs and 250 flashes (full power, fully chargedNi-MH 2700mAh).

When the lens is very close to a subject a traditional hotshoe mounted flash is quite a long way above the lens axis, and in fact much of its light may be unable to even fall onto the subject. The circular flash head of the AF 160 FC solves this problem by ‘wrapping around’ the lens and providing a full and even coverage,eliminating shadows even at extreme close distances.

Because in this on-lens configuration the size of the light source is large in relation to a very small subject (eg a tiny flower or insect) then the quality of the light is soft. This is more difficult to achieve with a traditional type flash headwhich would have to be further away, therefore smaller in relation and so a harder quality of light.

It is possible to create some lighting contrast within the scene by adjusting the ratio of output between the two sides of the flash head. This is achieved with a ‘Ratio’control switch that adjusts the relative output of each pair of light tubes in the circular flash head. Further re-distribution of the contrast in the sceneis possible by rotating the flash head around the lens.

PracticalConsiderations

The AF 160 FC is supplied in a kit that includes 4 lens adaptor rings and a further special ‘Macro’ adaptor for use with the Pentax D FA 100mm macro lens. When using normal lenses the adaptor rings screw onto the lens filter thread. There are adaptors for 49mm, 52mm, 58mm & 67mm size lenses. The process is to firstly (with the lens already on the camera) screw the correct adaptor ring into place ands econdly to attach the circular flash head onto the adaptor. There are two release buttons around the edge of the flash head and 4 tabs that click onto a groove on the adaptor ring.

With the Macro lens then the special adaptor is pushed onto the lens outer hood and turned clockwise to lock it in place, then the circular flash head is mounted in the same way onto the adaptor.

There are some limitations to consider with specific lens types and some particular lenses,and these are listed in a table in the flash manual ; for example the DA 40 Ltd appears to be too small as the flash head interferes with the camera, and any lenses that have rotating front elements are listed as having ‘unstable focusing’ (however these are all FA type lenses).

Some DA lenses have issues with vignetting at their wider ends, for example the DA 16-45mm and DA 17-70mm …… however perhaps close up flash photography is not too common at these sorts of focal lengths.The DA* 50-135mm is reported as vignetting between 50-90mm which may be an issue, although surely we can just zoom in more and move a little back if need be. Apart from the 40mm mentioned already there are no DA primes listed as having any compatibility issues with this flash unit.

It should perhaps be pointed out that thisinformation is based on the APS-C sized sensor, and so far no information exists relating to lens/flash compatibility with this unit and the K1 DSLR, norof course for the latest D FA zoom lenses.

Mode sand Functions

The AF 160 FC flash supports the following flash exposure modes :

P-TTL with Pentax Digital SLR cameras (and the MZ-S, MZ-L/MZ-6/ZX-L film models)
TTL with Pentax Film SLR cameras (and the istD range DSLRs)
Manual Mode with all Pentax cameras

The flash will automatically detect the correct automatic mode to use, depending on the camera it is attached to. For the user the only setting to make is the ‘Auto’ option,and the appropriate TTL mode will apply. Note that the exposure compensation settings only apply to P-TTL mode operation.

Flash mode and lens compatibility is essentially the same as described in this Guide for the other Pentax flashes, ie P-TTL is only compatible with autofocus lenses, and those with an aperture ring need to be set to the A position. Working with an M or K type lens, or an A type with the aperture ring not in the A position will cause the flash to fire at full power in P-TTL mode …. Switch to one of the Manual power levels instead.

The flash doesnot offer High Speed Sync, Second Curtain sync or Contrast Control Sync modes.There is also no support for Wireless operations, neither P-TTL nor optical slave types.

Flash Exposure Control

There is a single simple control dial that is used to set the Flash Mode and also to control the Flash Exposure in both P-TTL and Manual modes. The ‘Auto’ position sets P-TTL or TTL (depending on the camera used) and if the flash is operated with this setting then the flash exposure will be as determined by the automatic metering system.

There are 3 Flash Compensation settings on the dial, and so long as the camera is P-TTLcompatible and an autofocus lens is being used then these settings will influence the flash output accordingly. The three compensations are (in‘stops’) : +0.5, -0.5, -1.0. Including the Auto ‘0’ position makes a range of 1.5 stops in half stop increments.

In common withthe other Pentax flashes, making further Flash compensation settings on the camera will compound the effects, adding potentially a range between -3 through +1.5 stops (a 4.5 stop range). Whether this can be applied in practice will depend on the distances, aperture and ISO involved; clearly with very small flash to subject distances, wide apertures and higher ISOs then the ability to lowerthe flash exposure by -3 stops will be rather limited. Using a low ISO and small aperture will help in this respect greatly.

There is no actual ‘M’ setting on the dial, but rather the manual power levels are activated by simply setting the dial to the required output. There are three power settings; Full, ¼ & 1/16th. Manual Camera exposure mode would be an intuitive method of working combined with Manual flash settings, and if there are further fine tunings of flash exposure needed, in between or beyond the 3 specific power steps, then small adjustments of ISO or aperture could be applied.

Flash Head Output (Lighting Ratio)Control and Modelling

The balance of light output from around the circular flash head is adjusted with this control switch, located on the back of the circular flash head (facing the photographer when the flash head is attached to the lens). This has the effect of creating a ‘lighting ratio’ between the two different halves of the flash head, therefore introducing some contrast within the scene. By rotating the flash head then the shape of this contrasting light can be moved around to suit the subject. The actual total amount of flash exposure does not change, it is only the distribution of the total flash output between the two halves of the flash head thatchanges.

Thecontrol switch has 5 settings : 1 / 2 /3 / 4 / 5

• 1 Ratio 1:0 All the light is from the left half
• 2 Ratio 3:1 There is three times the light from the left half as from the right
• 3 Ratio 1:1 Equal output from both halves(no contrast)
• 4 Ratio 1:3 There is three times the light from the right half as from the left
• 5 Ratio 0:1 All the light is from the right half

There is a‘Modelling’ button on the controller unit. When pressed the flash tubes willilluminate continuously, allowing assessment of the contrast and fall of light in the scene. Press the modelling button again to switch off the lights. The‘Lighting ratio’ control setting will have an effect also on the modelling light output, allowing visualization of the fall of light over the scene.

---

Last edited by mcgregni; 03-30-2017 at 01:03 PM.

[pathdoc]

Observation:

I was playing around with my AF080C on the K-5 yesterday at lunchtime (the *istDS is at home), and I found it a much easier beast to use with the 100/2.8 WR macro than with the 35/2.8 Limited Macro. The 100/2.8 seems to eat a little more light, being a longer focal length, and the minimum focal distance for 1:1 is significantly longer also (perhaps these are the same effect). In addition, I have one more stop to play with (f/32) on the 100/2.8 WR.

What it all boils down to is this - at f/22 and ISO 80 at MFD (for 1:1), I find it difficult to avoid overexposure with the DA 35, even with 1/4 power selected on the AF's control unit. With the D-FA 100, it is a different matter; at this ISO and MFD, I find myself having to turn the power up to full (there is full or 1/4; nothing in between) or stop down a little less. This gives me lots of flexibility and wriggle room with very close-distance shooting.

Be aware, of course, that if you do find and go with a secondhand AF080C or some of the third-party options, you may have to juggle settings and take the results as you find them. The (admittedly expensive) AF160FC will save you and your patients frustration from having to try multiple shots to get a good result if the person using the camera is relatively unskilled or unpractised. The things I take pictures of at work are either excised organs or no longer among the living, and in no position to care how many shots I need to get it right, so my demands are less exacting in that respect.

[p38arover]

Pentax-A Dental macro 100mm?

SMC Pentax-A Dental Macro 100/4.0 – B I T Z