Multiframe panoramas have the added advantage of many more pixels than a standard frame shot taken with a single exposure and as a result lend themselves to the production of large prints.
The pixel dimensions and file sizes from stitched panoramas are considerably larger than single frame images. This one from my Fuji X-Pro1 with the XF16mm lens is 8322 pixels by 3668 pixels. That is more than 30 million pixels and it would need a 46 million pixel camera with a 3×2 sensor to capture it like the Canon 5Dmk4. But Canon don’t make a lens that will resolve this kind of detail – yet.
By using the latest software like Lightroom 6 (cc) with built in RAW photo merge we can create stunning multi image panoramas. No matter how good the software is it needs great source images to work with. Here is my guide to making great panoramic photographs using Nodal shift.
In days of old, roll film cameras with panoramic proportions 6×17 or even 5″x4″ cameras were used to create negatives large enough to make immensely detailed prints for display. Nowadays we can use carefully shot multiple exposures of a scene taken on a small easy to carry camera and stitch them together however there are problems to overcome.
When you shoot multiframe or sweep panoramas with the camera panned on a standard tripod the side swipe of the lens introduces parallax errors at the image join points. The post production software tries to fudge these irregularities and often delivers panoramas that look great at a distance but suffer at the detail level where the individual frames join.
It doesn’t have to be this way because with the rotation of the camera around the nodal point of the lens such distortions are completely eradicated leaving perfect joins. This even works for the panoramas created in camera with the panorama function.
This scene captured in a woodland near Bristol was stitched from 4 frames. The boats are part of a temporary art installation. Unfortunately the light was poor when I visited the site to test out my nodal shift system. Even the leaves and twigs in the foreground stitched perfectly. The level of micro detail in this 5 frame image is startling.
What is a node?
The node of a lens is its optical centre point. Parallax errors in panoramic pictures can be eliminated by placing the rotation point of the camera at the lens node point. Some lenses have their nodal centre at a point within the front lens group while other lenses seem to have their nodal points near the exit or rear of the lens. Some zooms like the Fuji XF10-24mm have the same nodal point irrespective of focal length selected while other Fuji zooms have nodal points that vary with each focal length setting of the lens. There is absolutely no way to accurately guess a lens nodal point but there is an easy way to discover it using a tripod, a nodal shift plate and some basic household implements. See my method detailed below.
A Neewer 140mm Nodal shift plate and the Neewer fluid panning device are okay as budget entry level kit. The Sunwayfoto kit is a better quality all round.
How does the nodal shift plate work?
A nodal shift plate allows the camera and lens to be moved forward or backward to an accurate predetermined position relative the point of rotation so that the unit can rotate about the node of the lens thus eliminating parallax errors in multiframe panoramas.
What bits and bobs do I need to make super high resolution panoramic images?
- An L plate for your camera with a lens centre marker. If you already have an L plate without one you might be able to scratch a mark onto the plate in exactly the right position using a scriber. I have a Really Right Stuff L plate for my Fuji X-Pro1 and it is perfect for this application. The L plate I have on my X-T1 is not of the same quality and so I use my X-Pro 1 for all my pano needs.
- A rotation device. I put this on top of my RRS ball and socket head and I use the head to level the rotator. The camera rotation happens on the level rotator and not at the ball head. This means I don’t have to faff around getting my tripod absolutely level. The rotation device has handy degree markings on it too plus three spirit levels. I bought the Neewer model and to be honest it’s not great. It will do me but there are more expensive models out there and again, you will probably get what you pay for.
- A nodal plate. This comes in different lengths and my friend Len Martin had done some research to determine the 140mm plate is perfect for the Fuji X system and that was good enough for me. Get a plate that is too long and you will see it in the bottom of the shot. The 140mm plate is out of shot even when using the 10-24mm lens at the 10mm setting and the 14mm lens too. If the plate is too short there won’t be enough travel to correctly offset some of the lenses. Len has the Sunwayfoto plate and it is a better made plate than the Neewer one that I have but they both do the same thing.
- A tripod. I use a Sirui carbon fibre professional travel tripod and it is excellent. It’s by far the best build quality of all the tripods on display at The Photography Show in the UK and at the CP+ show in Japan. I’d say it’s even better made than my uber expensive carbon fibre Gitzo monopod.
In measuring mode the camera is rigged horizontally. The nodal setting is read on the long scale on the slide. Here you can just make out that it is set at 95mm.
A tape target like this one temporarily stuck on the wall of my house is used in the calibration process described below.
How do I determine the nodal points of each of my lenses
(You only ever need to do this exercise once for each lens)
- Set up a tripod at 8 meters from a tree or wall in your home, garden, a local park or just about anywhere.
- Set a thin stick in a vertical orientation halfway between the tripod and the wall or tree. You can use a bamboo cane, a piece of dowel or improvise like I did. I used a reflector holder arm on a lighting stand. The thinner the stick the better.
- Place 150mm of sticky tape horizontally on the back wall or tree at the same height as the tripod. You can use masking tape, silver or white gaffa tape etc. With a black marker pen draw vertical lines on the tape as shown.
- Rig the rotator on the ball head and level it. Slide in the nodal plate and lock it off at some arbitrary middle point. Set the Camera with lens attached in landscape orientation and clamp it in the nodal plate. The nodal point of the lens is the same in both the vertical and horizontal orientations. We use horizontal mode for our tests to give more precise measurements.
- Set the camera to manual focus and f/11. Set the ISO to 200 and adjust the shutter speed to give a well exposed image. Focus somewhere between the stick and the tape.
- Using just the LCD or EVF ensure the stick is bang in the middle on the exact line between the camera and the markings on the white tape. The stick or tripod will need to be moved to ensure accurate centering. Use the zoomed in focus aid facility to help you and if there is insufficient depth of field take a shot and zoom in on the playback. Once the camera, stick and tape are perfectly aligned move onto the next step.
- To get the nodal plate position in the right ball-park release the panning lock on the rotator and swing the camera left then right. Does the stick appear to move left or right in relation to the tape? If not go to 8. If yes you will need to move the slider in the rotator. If when you pan the camera left to put the target on the right of frame the stick moves right relative to the tape markings you will need to slide the plate back and visa versa. Adjust the forward and back position until it looks good by eye. You can now move onto fine calibration.
- Pan the camera to the dead centre position. Use the focus aid box in the centre position of the screen to assist you. Take a shot. playback the shot and zoom into 100% using the quick view function. Check the stick is still perfectly aligned between the markings. Next pan the camera left so the stick and tape are on the extreme right hand side. Take a shot and press playback. quick zoom in to 100% and scoot the shot over to the right hand side to check that it looks the same as the shot you took in the centre position. If the stick has moved right and there are more lines visible on the left of the target the nodal slider needs to be moved back towards you. Repeat the process until both the centre and right hand pictures match. Once they do pan the camera right so that the target is on the extreme left. Compare all the shots and adjust the plate position as required. After several goes at this you will become mm accurate on the the slider position. Notes: I like to format my card after each series of tests so I know exactly what I’m looking at. With Fuji cameras use jpeg fine setting for these tests. If you use RAW only you won’t be able to zoom in on playback to 100% as Fuji cameras only save 50% sized jpegs embedded with RAW files.
- You now know the exact nodal point of your lens. Make a note of the settings and numbers used so you can recall them when you are out on location. I use the notes function on my phone and keep a print out in my camera bag too.
- Repeat this process from No.7 for each of your lenses.
My results look like this:
For this process I used my Neewer 140mm ‘Arca Swiss’ professional rail nodal slide on a Neewer multi-purpose professional quick release fluid panoramic panning base. My X-Pro1 has an RRS L plate and grip.
Fuji XF10-24mm lens @ 24mm on X-Pro1 = 24mm
Fuji XF10-24mm lens @ 10mm on X-Pro1 = 24mm
Fuji XF14mm lens on X-Pro1 = 55mm
Fuji XF16mm lens on X-Pro1 = 49mm
Fuji XF18-55mm @ 18mm on X-Pro1 = 47mm
Fuji XF18-55mm @ 55mm on X-Pro1 = 74mm
Fuji XF23mm lens on X-Pro1 = 65mm
Fuji XF35mm lens on X-Pro1 = 86mm
Fuji XF50-140mm @ 50mm on X-Pro1 = 5mm
Fuji XF50-140mm @ 140mm on X-Pro1 = 95mm
Fuji XF55-200mm @ 55mm on X-Pro1 = 35mm
Fuji XF55-200mm @ 200mm on X-Pro1 = 80mm
Fuji XF56mm lens on X-Pro1 = 93mm
The settings for each lens were determined using an f/11 aperture and the standard parallax test described above. I set the foreground pole at 4m and the background marker tape at 8m.
When shooting panorama photographs the camera is rigged vertically using the L plate. The frame top left shows the camera rigged so that the axis of the lens is exactly on the centre line of the rotation. This is why it is good to have accurate markings on your L bracket.
How to shoot panoramas:
Set your tripod in the right place at the right height the first time. This is how I was taught to do it at the BBC: I determine the camera position of my shot hand held using the LCD of the camera to preview the picture. Once I have the correct camera position I make a 3D note of where it is. I always use myself as a guide to the height above the ground- shirt pocket height or knee height etc and then I place a leaf or similar object on the ground directly beneath the centre of the camera. I can then accurately rig the tripod in the right place at the correct height the first time.
Level the panoramic panning base using the ball and socket head and lock off the ball head completely. Insert the nodal slider and lock it off at the predetermined position required for the chosen lens. Set the camera upright and in the exact centre of the slider using the centre point marking on the L bracket. Shooting with the camera upright delivers the most pixels in the vertical plane. I can always add more pixels horizontally by shooting more frames over a bigger rotational angle.
Overlap 1/4 of each frame to give the software options at the stitching process. With a precision rotation device you can set the first frame at 0 degrees and then add the required number of degrees for each frame for the corresponding lens that’s being used. Or you can just use elements in the frame to guess. The number of degrees of rotation required for each lens can easily be predetermined and added to your notes.
Pan the camera precisely at the exposure stage, lock it off and let it completely settle before each exposure. I often use 1/4 second or longer to get the optimal detail in my image.
Use between f/4 and f/11 for panoramas and avoid f/16 and above. Some lenses deliver the best overall performance at f/8 or thereabouts. By f/16 iris diffraction is starting to reduce the overall resolution of the lens and no more depth of field advantage can be had.
If applicable switch off optical image stabilisation. You should hear a small clunk when the rotating lens element settles in it’s optimum place of rest.
Wait for gusts of wind to settle if there are grasses or leaves in the shot. Dont dilly dally between frames if there are clouds in shot moving across the sky.
Place people clearly in the central part of one or each of the frames to be stitched and avoid the overlap sections to create stunning figure in the landscape scenes. I start with the frame containing the person then shoot the frames either side once I have the perfect pose without blinks etc.
That’s the technical bit. Now I’m off to shoot some panoramas. Panorama prints look great on walls above sofas or beds. Have fun and stay inspired. Vertical panoramas look good too.
Please ask questions or make comments on the techniques discussed here in the Facebook or comments section below rather than on general Facebook or Twitter timelines. That way we can all benefit from the discussion and replies. Thank you :)
The boats in woods project is called Withdrawn and is a creation by Luke Jerram. They are due to be on display until September.
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