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M8 Panos --Nodal point for M lenses

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I really enjoy doing panos with the M8. So far, I have done landscapes hand-held b stitching with CS3 several shots in portrait format. Works reasonably well, although you loose a bit at the top and at the bottom because of camera movement between shots. That can be avoided with a tripod, of course.

 

I now would like to expand my use of this technique, and also stitch together shots of objects of shorter distance. From research on the net I am aware of the technique, and in particular the importance of rotating the camera around the nodal point (or is it the nadal point?). I also saw somewhere an instruction on how to determine that point.

 

As I don't have much time and am generally lazy

, I wonder whether someone on this forum already did this exercise, determined the nodal point for M lenses, and is willing to share his or her results.

 

In a similar vein, while CS3 is ok for simple panos, I think there are better solutions out there. Any recommendations.

 

Thanks.

 

Georg

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For software recommendations, do a search here for "Panorama"

 

The subject comes up regularly.

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If I'm not mistaken, the information you're looking for is the "Entrance Pupil" that Leica provides in each lens' data sheet. For example, the data sheet for the 50/1.4 ASPH contains this:

 

Entrance pupil: 25.7 mm (related to the first lens surface in light direction)

 

Usually I have a harder time finding the plane that vertically bisects the lens. At best, it's a close guess. The axis of rotation should lie on this plane (I think).

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Guest bwcolor

Do a Google search. One minute brought me a good collection of answers.

 

The nodal point of the normal, non-retrofocus and non-telephoto lens is close to the center of the lens grouping in the lens mount, frequently where the diaphram is.

 

My own experience in doing panoramas with a couple of different cameras, is to buy or make a gadget which centers the axis of rotation of the camera on the tripod head, so that the center of the optical groupings in the lens mount is above that axis of rotation.

 

Good luck.

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If I'm not mistaken, the information you're looking for is the "Entrance Pupil" that Leica provides in each lens' data sheet. For example, the data sheet for the 50/1.4 ASPH contains this:

 

Entrance pupil: 25.7 mm (related to the first lens surface in light direction)

 

Usually I have a harder time finding the plane that vertically bisects the lens. At best, it's a close guess. The axis of rotation should lie on this plane (I think).

 

I think that's correct, see here. So the information Leica provides should save trial and error.

 

Bob.

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IMHO, you can tie your self in knots worrying about things like nodal points or you can go out and get on with it and take some shots.

 

Stitching software gets better and better (CS4 is better than CS3, for example) and is more tolerant of photographers' inexactitudes.

 

Another way of increasing your margins of tolerance is to over-shoot the scene. By that, I mean take some extra shots to capture the marginal areas of the pano scene even if it means just having more sky or ground foreground than you really need. It is easier than going back to get that chunk that fills in your gap. You can always crop out what you don't need.

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I shoot pano's regularly as large as 3 high and 9 across (in portrait mode ), often with near and far field subjects. I use a really right stuff ( Welcome to Really Right Stuff ) ultimate pano rig which will let you position for both horizontal and vertical nodal point. It is expensive, but if you are serious about pano's you will eventually use their gear so you can save time and money by doing it first. The Acratech levelling base is easier and lighter than a ball head in this application

 

In an RF prime lens, the nodal point is almost always at the diaphragm, this is one of the reasons why these lenses have the best 'bokeh.

 

I started using PS for stitching, but now almost always use Autopano Pro. It is much easier, and can compensate for nodal point being slightly off.

 

I would not however use its Raw mode, you will get better results using your normal Raw workflow, to produce Tiff's and using autopano on the Tiff's.

 

Pano's shot this way give resolution way beyond even large format, as long as the subject and light hold still for a few minutes.

 

I hope this is helpful.

 

Regards ... Harold

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If I'm not mistaken, the information you're looking for is the "Entrance Pupil" that Leica provides in each lens' data sheet.

Indeed it is. The no-parallax point is the center of the entrance pupil, not one of the two nodal points of the lens.

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Georg - As Andy said, use the search function because I recall one thread in particular with a wealth of information on using the M8 for panoramas, and some compelling examples too. I myself have described how to set a panorama rig for 'nodal' imaging. It's gone 1.00am here, I'm tired, but I'll look in tomorrow and see if I can help. It's a subject that interests many forum members.

 

.............. Chris

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I'd highly recommend Autopano software for stitching hand held shots or those made on a tripod without a QTVR head. Of course it is also good software to use for shots taken using a QTVR head.

 

If you have objects within about 20 feet of the lens, you will need to rotate on the rear nodal point to get perfectly aligned images. Even for more distant objects, you have to be careful when rotating the camera hand held that you don't drift too far off center when rotating.

 

The $200 Nodal Ninja 3 will be fine for use with an M8. It is very light (1lb) and small. So you won't be burdened when taking it with you. The $400 model 5 will handle heavier cameras and long lenses but is a bit heavier yet still under 2 lbs. I have the model 5 and it is very well made. With just a little trial and error, you can find the rear nodal point. (Although this is much easier to do with an SLR.)

 

Panoramic Tripod Heads, Universal Brackets, QTVR Heads, Compact Lightweight for Amatuers and Professionals

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Thank you all for the helpful comments. I will do some more search on this forum and beyond.

 

Just wonder whether people have any views on the different tripod heads, e.g., nodal ninja as compared to Really Right Stuff.

 

Georg

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Georg - Ok, I think you need to do some reading. Do a search for panorama, nodal and look at every thread. The reason being that you will find something useful in each one, including images of working set-ups. Some panorama rigs are badly designed, and if you need to transport them easily it's good to consider their build, or whether the idiot who designed a rig didn't think that where the spirit bubble is placed - it can't be seen. An ideal rig is sturdy, and portable, and easy to set level.

 

In this thread started by Max Alfy :

 

http://www.l-camera-forum.com/leica-forum/leica-m8-forum/31495-two-mysterious-measurements.html

 

I gave an answer about setting an M8 in a rig for 'nodal' panoramas :

 

If you are asking how to set up the M8 with a specific lens for 'nodal point' photography to make panoramas; it's easy. You will, of course, need a panoramic head with sideways, and forwards/backwards shifts. In a well lit room fix your M8 in your panoramic head on a tripod with the lens nodal point region roughly over the centre of the tripod [i focused the lens for a typical landscape focusing distance but I'm uncertain whether the nodal point shifts with focusing].

 

You will need a thin line object close to the lens [i mounted a vertical screwdriver on a stand], your second target needs to be broader and a few feet away [ I used the end thickness of a white painted door].

 

Centre the 'close line' so that on your exposed screen it is exactly in the middle of the second target, and by swinging the panoramic head a set amount to the left and right for exposures you will observe the image of the close line shift off centre, adjust the position of the camera on the [say] forwards/backwards rack so the least displacement of the the close line from centre of the second target is achieved. Go through the same process with the panoramic head's sideways rack, until finally you can make exposures so the image of the close line remains centred in the second target when exposures are made after turning the panoramic head. The rig is now tuned for nodal point photography.

 

It was a hell of a lot easier to do than to describe. I advise using a focusing loupe to inspect the screen after exposures, take your time, scratch your head, and poor yourself a glass of wine.....

 

Enjoy the threads, there's very useful information and good links contained in them.

 

................... Chris

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IMHO, you can tie your self in knots worrying about things like nodal points or you can go out and get on with it and take some shots.

 

 

Unless you get really close-up, like 1 meter or so, don't worry too much. Somewhere in the middel between the two lensgroups, indeed where in RF lenses the diaphragm sits, works fine. Stitching software will do the rest. Autopano is good. I use PTGui: Photo stitching software 360 degree Panorama image software - PTGui. A matter of taste and of what you are used to.

 

This Pano South Africa and Namibia Panorama's was taken at 1 meter range, with a WATE at 21mm, and I did not worry about the nodal point too much. I use a nodal point setup, but never went through the pains of exactly finding the right spot for each lenssetting

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....Stitching software gets better and better (CS4 is better than CS3, for example) and is more tolerant of photographers' inexactitudes........

 

Philip - Having just re-read the thread referenced above, it was a delight to again see your [handheld] stitched panorama of Grand Central Station [?], That Photoshop stitching has improved again makes it very desirable. How about posting a panorama which contains complex geometry; an urban nightmare example for stitching?

 

................ Chris

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Philip - Having just re-read the thread referenced above, it was a delight to again see your [handheld] stitched panorama of Grand Central Station [?], That Photoshop stitching has improved again makes it very desirable. How about posting a panorama which contains complex geometry; an urban nightmare example for stitching?

 

................ Chris

Thank you, Chris, for remembering my picture of Grand Central (Terminal/Station). I have only had CS4 for a few days so far and I have not yet finished my must recent photos (of Winchester Cathedral). When I have done so, I will post as you suggest.

 

My early observations are, however, that the auto-stitching ("Photomerge" Adobe calls it) seems faster and has some appealing characteristics. For one thing, it does a somewhat better job of balancing colours from sub-image to sub-image. Also, there is an option to automatically deal with vignetting which seems to work very well. As I am sure you know, this can be a real problem if there is a continuous blue sky in the panorama and your lens/sensor combination has some vulnerability to vignetting. CS4 seems to have done a marvelous job with the (uncharacteristic) clear blue sky on the day I was shooting. CS4 seems to be much more "hands off" with improved processes that are difficult to second guess; less manual intervention seems to be called for.

 

I almost never use a tripod, preferring instead the flexibility and convenience of the bipod sticking out from my bottom. I try to maintain an informal fixed nodal point by rotating my body, head, hands and camera in a way that minimizes nodal point displacement. I reckon that if I am taking in a scene that can be measured in hundreds of yards or meters or more, displacement of an inch or two of the nodal point cannot be critical. That has been my experience. Now, if one is dealing with scenes that are measured in in inches or centimeters, I can appreciate the value of having a device that reliably fixes the nodal point as has been discussed in this thread.

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Actually, Georg, the more I think about this, the more I am inclined to advise you more strongly not to get wrapped up in solutions that applied to an earlier technology and just get on with shooting. That is, tripods with pano heads were necessary in the days of film photography but they are much less so in digital. Therefore, this equipment will actually stand in the way of your taking photographs rather than enhancing the photos you want to take.

 

For example, I took a hand-held panorama photograph from the deck of a moving ferry boat consisting of five frames through a 75 mm lens. Obviously, the nodal point was moving out of my control up and down, side to side, and receding from the scene at a rate of knots. Even if I had used a tripod and pano head, I never would have been able to fix the nodal point or level the equipment. See East River Harbor Scene on Flickr - Photo Sharing! and look at the larger size files there on Flickr. I think PhotoShop CS3 overcame these difficulties in exemplary fashion. So, why bother with more gear?

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