Digital Infrared Photography with an SLR Film Camera

My digital back Nikon FE can achieve nice results with infrared photography.  I have been incorrect in suggesting that the IR Filter needs to be swapped with a clear glass filter to achieve focus when using the bare sensor for infrared photography. This is a myth as I have found that infrared light works on a slightly different focal length, so no wonder I was having focus issues. On many old SLR lenses there is a red dot on prime and a curving red line on zoom, or a straight red line on zoom lenses like the Tamron SP 35-80 2:8. These red marks are there to re-adjust the focus for infrared film after having first focused on the subject via the split prisms in the view finder. An example is to focus on a subject at 2.5 metres but your red dot or line will be at say 3 metres, therefore you need to turn the focus so the 3 metre mark is on the main focusing mark and your infrared photo will then be perfectly focused when exposed. 
Update 17th Jan 2017 - I have since sanded a bit more off the rebated edge of the sensor so sinking it further into the film plane. This has improved my focus in normal colour (filter inserted) at F1.8 to a very acceptable level. Subsequently with the IR/AA filter removed and shooting on the bare sensor, my focus is much more in line with the normal focus marks on the lens and in the split prism viewfinder. There is still a small amount of difference as IR light travels at a different wavelength. Whether the bare sensor reacts the same as IR film is another matter. If you start adding say red or yellow filters to the front of the lens then this will also change the wavelength to focus. So I think it comes down to rebating the sensor to the best possible tolerance with the IR/AA filter installed and then conduct tests without the IR/AA to see where the focus is at with different lenses shooting in IR. Here is a good article on focussing in infrared.  Focussing in Infrared

Nikkor and two Tamron zooms with red IR focus line.

Another lesson I've had to learn is the dreaded White Balance setting on the Nex. If you use the Auto White Balance setting your photos will have a red tinge and only very blue sky will be blue. But when you use the iOS Photos program and edit filters to Mono, Tonal or Noir, your black and whites will be superb. However you can get a more realistic initial infrared photo in colour if you learn how to custom set the WB to a test photo. These test photos can be of a grey wall or green grass. I suggest you check the Nex manual and the internet to learn how to do this. Once the WB is custom set for the light conditions, you will find that the other colour filters in iOS Photos (or I guess PhotoShop) will provide some exciting filters to your photos and the B&W photos will still be superb with no change from your auto WB setting.

To set the White Balance test photo through the Nikon you need to coordinate the shutters simultaneously at the correct speed. Well that is way too hard. So instead set WB manually on “‘K’ C.Temp/Filter” and try 2900K G9 or G8 as the green strength. This seems to give a pretty good result on a sunny day. Experiment with different K & G settings.

Auto White Balance result

White Balance setting 2900K G9

My previous post mentioned the light meter calibration for infrared. There is about 2 stops extra light striking the bare CMOS sensor than when it has the IR Filter attached (or located within the SLR body). As the SLR light meter is reading light from the mirror before it reaches the sensor, then the SLR is no longer matching the Nex bare sensor reading. My really easy fix is to set the Nikon at 1600 ASA and the Sony Nex at 400 ISO. This brings the light meter to a near correct calibration. I have found in sunny light I get a more exact calibration with the Nikon adjusted to the next mark which must be 2133 ASA.  But a few test shots and some tweaking of the ASA approximately 2 stops above the ISO will give you the correct calibration for the light your working with. You can use the compensation dial to tweak the exposure instead of moving the ASA.

Infrared photography was not my initial reason for inventing this Nikon/Nex hybrid camera. But it has shone through as a fantastic concept for this camera project. Infrared photography opens up a whole new dimension and to be able to combine this with SLR cameras and lenses that were designed to use infrared film is just awesome. If you are thinking about converting a DSLR to infrared then I would strongly suggest you look at this option of using a Sony Nex as the electric film on your favourite SLR kit that has been sitting in the cupboard feeling very unloved for the past 15 years. 

If you are just going to use this camera for infrared then you do not need to worry as to whether or not you can fit the IR Filter up behind the mirror of the SLR. For specifically as a dedicated infrared SLR, you can convert any SLR. Now there is a strong statement but I believe this to be correct. You only need to remove the IR Filter from the Nex APS-C sensor and rebate the sensor to the exact Film Plane measurement. It's your call whether to modify the existing camera back permanently, or make a custom back so you could still change back to film. You should make a custom back for collector cameras and keep the original in tact as good quality film cameras are increasing in value now.

If you have any queries or need advice if tackling this project then I am happy to assist.
Robin.  xovercameras@gmail.com
Click on the photos to enlarge.

An average front yard transformed to a magic land in IR

Roses are Infrared

Infrared B&W Noir

Using a Film Camera converted to Digital

Learning to use the Nikon FE with electric film

Nikon FE & Tamron SP

I have had the Nikon FE working with the Nex electric film for a few weeks now and ironed out some bugs. I have even discovered a few different ways to use it and a few surprises that I did not think possible.

My old MD11 motor drive has packed it in, but I have left it on as I prefer the handle grip and the extension of the battery compartment means I can fix a tripod or the Metz flash to the tripod mount. The camera is just more stable with the MD11 attached.

Playing around with the Nex settings I found I could custom set the centre wheel button to the ISO setting. This has made it really quick to change the ISO which needs to match the ASA on the Nikon. I shake a bit so this is handy for me to keep the Nikon speed above 125th in most conditions. The camera worked very well on 3200 ISO&ASA at an indoor conference with no flash.

Nikon FE digital with Metz flash

Speaking of using a flash, I tried the Nikon out with my old Metz 45CT flash attached. You would not want to connect this powerful flash to a DSLR as it could melt the electronics. But running off the SLR Nikon is what it is made for. The results have been terrific and setting the Nex to post process out the noise works well. Click this Lorikeet photo to see the result.

I've fixed a small raised rubber stopper to the Nex shutter button which makes it easy to trigger with my thumb knuckle without looking for it, as the Nex is inverted. I use the Nex in a couple of speed settings to electrify the sensor. If I want a bit of time to adjust focus, I set it to 6 seconds. Then I trigger the Nex, fine tune focus and fire off the Nikon before that time. The Nex then processes the shot, which can be a bit slow if the Long Exposure NR is on. The other method is to set the Nex to Bulb. I then trigger the Nex and fire off the Nikon whilst the Nex is held on. Processing can be short or long depending on the time the sensor was electrified. I keep auto Playback turned off as this slows things up. Just press the Playback button whenever I need to check a photo.

Something unexpected has turned up. Naturally the Nex is set on Manual but if I have it set on Bulb and put the Nikon on Bulb and hold the Nikon shutter open, then the Nex adjusts automatically to the light coming in and gives perfect Live View pretty much without having to adjust the lens aperture setting. But if I have the Nex set at say 6 seconds, the Live View just whites out until I start adjusting the speed on the Nex and aperture on the Nikon until the settings are close to what the Nex light meter is recording. So using the first method with both on Bulb I can frame a shot perfectly and play around with focussing using the Nex LCD and its Manual Focus assist button to zoom in. Also it's Focus Peaking Level works if you need that sort of thing.

The Nikon FE is renowned as an extremely good night time camera. It's versatile light meter will hold the shutter open for over an hour to expose an image. With good quality colour film you can get some outstanding results.

Nikon FE 200ASA film
3 minute exposure

So I thought I would try the electric film setup at night. Using a 50mm Nikkor set at 1:8, Nikon on auto speed and Nex on bulb, I put a rubber band around the Nex to hold the sensor on and tripped the Nikon shutter. It wasn't real dark so the Nikon exposed in about 60 seconds. I released the Nex and played back the shot. It was covered in multi coloured spots which I googled and found they were hot spots on the sensor commonly called noise. So I repeated the process a few times with the Long Exposure NR on. Well the Nex takes about the same time as the exposure to then process out the noise, quite a wait between shots. This did work and the photos were a lot better. But there is a chalk and cheese difference between digital and film when it comes to night time photography. I will experiment some more and might do some simultaneous photography using 2 Nikon FE's one with film and one with electric film. Should be an interesting comparison. Although I am a bit dubious whether the Nex can handle an exposure longer than a few minutes.

Another surprise was the ability to shoot movies. This just involves holding the Nikon shutter open in Bulb, adjusting the lens aperture to an average setting and focusing. Click movie and the Nex adjusts the light intake and shoots a pretty good movie with sound. So I guess this means the Nex does not need its shutter for framing in movie mode.

The Nex certainly cannot take a photo by itself though. What I mean by that is the Nikon shutter is held open whilst the Nex is triggered at a speed it's light meter is asking for. The photo is always overexposed and pretty corrupted. Obviously the sensor needs a shutter to close off the light for a brief moment to process the shot.  Anyway that's not important as the photos are excellent with the Nikon taking the shots which is the purpose of this project.

I have set up a web site that explains how to fit a Nex to an SLR and a few other tricks to make it all work. Even a page on how to make a custom rear door.  Camera conversions

Summarising this project I can qualify that it has been an outstanding success and I couldn't be happier with the way the camera works and the quality of the photos. When I started the project I was pretty sure it would take good photos but I never expected Live View or Movie to work so well. The action of triggering the Nex before the Nikon is something I am getting used to. It is a bit heavy with the MD11 attached but it feels great to hold this way and quite well balanced. If your contemplating this project then I highly recommend it as the end result is very satisfying.

Robin Guymer   Email Link

Convert Film Camera to Digital - It Works!

Old 35mm Film Cameras can go Digital

Saturday 17th September 2016
I have spent half the day sanding down - remounting - testing, sanding down - remounting - testing, sanding down - remounting - testing. To eventually obtain focus on the cupboard knob at Nikon settings of Auto speed + F1:8 using a 1980 Nikon FE + Series E 50mm lens with a digital Sony Exmor 14mp APS-C cmos sensor now successfully mounted at the Film Plane.

Focus on door knob at F1.8 at approx 3.5 metres.
Sensor is almost at correct film plane.

My previous posts suggested that if the sensor was to come into contact with the film shutters, then they could be removed from the sensor and a replacement infra red filter could be mounted on the end of the lens. This was incorrect. The IR filter is attached to a thin lens plate. These two have an affect on focus. If removed the sensor has to be moved forward the equivalent distance to obtain focus. So it is a futile exercise thinking this will create space to adjust the sensor before it touches the camera shutters.

To overcome this I mounted the IR & Lens combo at the rear of an SP Tamron with an adaptall Nikon mount. This did work on retaining the same focus but the colour was washed out (probably as I had it round the wrong way).

I then studied the camera internally and could see that there was room behind the mirror to mount the IR & Lens combo against the shutter frame. Using a simple L shape frame of builders flashing with the filters mounted in the middle, this slips nicely in behind the mirror and does not foul any operation of the camera. Now I had a bare CMOS sensor with plenty of adjustment room to the shutters with the IR filters mounted just on the inside of the shutters that provide the necessary focus and infra red filtering.

Sensor IR Filter & Lens mounted in a L shaped frame.
This slips in neatly behind the mirror.

The sensor has a frame around it to keep the IR filter & lens above the sensor. Under this frame is a glass screen covering the sensor but this screen is 24.6mm wide. The width of the film rails is 24mm. The sensor could not be moved any closer unless this matter was resolved. I decided to not risk breaking the glass and felt that removing 0.4mm off the side of each film rail would make no difference to the camera being able to shoot film. It would just leave uneven edges if developed as prints - but who does that these days. All my developing involves scanning which crops the film as a neat rectangle anyway. So I filed each rail a bit thinner.

Now I had both plenty of depth to the shutter and width between rails to enable the sensor to move down into the film box rectangle. The sensor mount frame is a very hard plastic and I found the best way to reduce it was with plasterboard finishing sandpaper. After each sanding session I measured the small edges with a micrometer. Once all edges were near equal the sensor was reinstalled and tested. Where the focus disparage really shows up is at F1.8. I placed a chair with magazine copy 1 meter in front of my intended target and this helped identify that the focus was gradually coming closer after each adjustment session with the sandpaper.

Sensor adjusted for depth with filters removed.
Still good clearance from the shutters.

All SLR Cameras Possible
Even at the adjusted depth to the film plane, the hinges of the Nikon shutter do not touch the sensor. So now I can move the sensor into the centre. If they did touch the shutter then the sensor IR filter frame could be easily sanded down. This is a real winner for any film camera now. My Canon A1's have a depth to shutter of 2mm so now the  adjusted sensor will fit it also. If it fits both the Canon and Nikon then I will assume that this method will work for many film SLR cameras. The issue is no longer the sensor touching the shutter, but rather can the IR Filter/Lens combo be discreetly mounted behind the mirror against the inner frame of the shutters.

Lens Theory
As the Exmor CMOS sensor has the small frame to support the IR Filter/Lens a set distance away from the sensor, I theorise that by moving them to the other side of the shutter, so increasing the seperation distance, actually decreased the amount I had to remove from the sensor support to achieve the exact film plane mounting position.

Infra Red Photography
I experimented with removing the IR/Lens and just shooting with the bare sensor. These photos can be easily converted by Photoshop into stunning black and white. See this link. Mingthein Blog  But the focus is not correct without the IR/Lens and the sensor would need to be moved further in to compensate. However when shooting with no IR/Lens at smaller apertures the depth of field compensates the focus and the shots are reasonable. So it would be possible to take more off the sensor mounts to make it accurate focus for Infra Red photography and then add set height packers when shooting with the filters on for normal photography. The internal filter frame behind the mirror holds easily in situ with one piece of black tape and can be installed or removed in seconds. A set frame packer could be easy to make for the sensor adjustment. So the camera could be swapped from normal to IR photography in a minute or so. That's one up for film cameras compared to DSLR's.

Infra Red (in mono) when filter is removed.
Focus is not correct when IR/Lens are removed.

Focus accuracy is improved dramatically.
A bit more sanding and it will be accurate.

My next post will show a number of photos with the sensor correctly on the film plane. I will make them available for download in JPEG and RAW should you wish to check them in your software. By all means check the Exif files. They will read - Sony Nex - ISO 200 - F1.0 - Lens n/a - Speed 5 seconds. The Nikon FE took these photos not the the Sony.

As I have received a few enquiries as to how I am achieving this, once the camera is complete and mounted on the Nikon I will produce an informative manual in PDF explaining all the steps I took. This will save countless hours of work should you now be encouraged to take on this great project.

I can be contacted at email  Cross Over Cameras 

Please feel free to comment but keep it nice thanks.

Project 1 - Convert a Nikon FE to shoot Film & Digital

1980 Nikon FE to 15mp Digital

Update - Completed project at Youtube Nikon FE Digital

Rather than stripping the guts out of a digital camera to make a complex hybrid back, I am mounting the near complete Sony Nex with a 15mp APS/C sensor, on to a spare Nikon FE back. (Besides which, there is no way I can solder those small electronics.) This will retain the Nikon as a great film camera, or as a digital camera with a quick change over of the rear door. After trying various options this seems to be the best mounting position despite the screen being inverted. I only want the screen for the setup menu anyway. After that it will stay turned off.

The sensor is in position and is very close to the critical film plane to lens mount measurement. The biggest obstacle at present being the motherboard to sensor circuit board connections which need to be redesigned for shape and length. Work on this is proceeding slowly but with some positive signs despite the complexity and cost outlay. Actually this is costing way more than the purchase cost of both cameras combined.

The benefit of this experiment into the unknown is that if successful, the same removable back to the Nikon FE fits the other models of Nikon FE2, Nikon FM and Nikon FA. Maybe a few more, but this is all I am aware of at present.

A slightly used Nikon FE with front half of the Nex mounted.

Why do this?
I like the old film cameras of this era. The Canon A1's and Nikon FE's and FE2 that I own are a just superb machines to use. Shooting in film is difficult and challenging with black and white especially so. B&W is not too costly as I develop myself in Caffenol. But colour film is expensive to develop. So I thought it would be fun to have the best of both worlds, a great old camera that can shoot digital plus all those great old lenses put to use. Nikon FE & FE2 shots - Nikon FE  Nikon FE2

Economics
A few years ago this would not have been viable. But mirrorless cameras have been around for a while and there are 5 year old ones with the APS/C 15mp sensor. There is a heap of technology in a Sony Nex but as they age they become a throw away camera. Now you can buy all that technology for under $100 which is cheaper than a good Nikon FE. So it becomes an inexpensive project - if it works. A Nikon FE in 1980 was $300USD + 50mm lens $98 + Motor Drive $178 + Zoom lens $218. I reckon that money is worth $5,500 today. Gives these cameras a sense of worth. Check my Nikon FE night photos to see just how good they are at midnight pitch black photography on auto.

Sensor Mount
This seems to be the difficult part for any of the other conversion attempts found on google. The film plane to lens mount distance has to be near perfect. I think the tolerance for a Nikon FE is 0.02mm over 46.5mm. It is hard to ascertain just what the distance is from the lens mount to the cmos sensor face as there are some filters in the way plus the looped wire perimeter. However on the Nikon FE, FE2, FM & FA (maybe others) the shutter action is hinged on the side and the shutter works vertically. On the right side is the hinge mechanism. The APS/C sensor from the Nex when placed hard to the left gives room for the shutter hinge to work with the shutter curtains not touching the sensor filters. When I sat the sensor circuit board in place you would think it was made especially for the Nikon. Clearance from the shutter curtain of 0.10mm and the mounts for the circuit board fit exactly in between the outer film rails holding the sensor perfectly in position. My caliper measurements indicate I am really close to the 46.5mm. Only testing once it's working will confirm this. Will just have to allow for areas at the far right of the view finder will not be in the shot.

CMOS Sensor circuit board sits neatly between film rails.
There is still room for the shutter hinges to operate on the right side.

Sensor held in place with high strength tape.
Once shut the camera door holds it secure.

How it will Shoot - hopefully
I've already tested this through the open back of the Nikon and it works. First the Nex needs to have some presets done on the Settings Menu. Turn off nearly everything automatic. Autofocus Off. Lens recognition Off. Auto ISO Off, set it to say 400.
There are two options to shoot with.
Option 1: Set the Nex to Bulb. Hold on the Nex shutter button, take the photo with the Nikon, release the Nex button and the picture is processed.
Option 2: Set the Nex to say 10 seconds. Click the shutter button. Then take your time to focus and shoot the Nikon lets say at 1/250th F8 within 10 sec. The Nex closes it's shot and processes the picture.

Looks pretty Retro from the front with Nex just visible.

Next Project
Looking at the space inside the lower casing of the Nikon I think there is room for a microswitch that could be armed when the camera is cocked. If I can wire this on from a power source either from the Nikon or the Sony and fit a small actuator against the Sony shutter button then I may be able to syncronise the two cameras. If so the motor drive could be used. If I was good with electronics then it would be possible to wire it directly into the Sony Nex switch but the connections are tiny and I want to keep my projects as DIY & KISS.

Summary
I've stuck my neck out here posting all this before it's up and working but some of the above might be of interest to Nikon film camera owners who might offer some good tips. I am expecting to manufacture the prototype connection ribbons soon. If you have an interest in trying this project yourself and may require the connecting ribbons and detailed instructions of how I am doing all this then email me at Cross Over Cameras .

Update
Have received the gerber files for the new extension cables. The quotes so far are costly for a one off set but greatly reduced for quantity. So I will need some interest from other Nikon FE, FE2, FM and FA owners who would like to try this digital conversion too. My thoughts are to put this on Kickstarter to arrange extra funding which would cover having cables designed and produced for other Nex models and possibly other mirrorless cameras that would be suitable.

Cost Guide
As a rough estimate you could expect the following.
Extension cables and an easy to follow pdf manual. $50AUD
Sony Nex 5 14mp cameras can be purchased body only for around $100
See my basic tool guide on the Leica M3 post.

Hope you show some interest.
Feel free to comment but keep it constructive and nice. Thanks.