Large Format for Stitching

<p>So what is the general thought on using large format with small format (i.e. Nikon) cameras for stitching? I was thinking of building a Sinar F for this exact reason. It would allow me a single plane to stitch and also allow me to use the movements off the front. This is for architecture and landscapes. I have been using a pano head currently, but I am not happy with the field curvature and would like to keep my camera on a single plane.</p>

<p>Currently looking at doing a Sinar F and a digital lens. Camera body is a D200 and will be upgrading that sometime this year.</p>

<p>Why not use a VR system designed to do exactly what you are trying to do? That would let you work with the widest to the longest lenses without vignetting or having problems reaching infinity due to the thickness of the Sinar and be lighter, faster and more convenient to lug around. And, if you need to find the nodal point, be much more precise then a view camera's standards.<br>

Lastly, what field curvature? Is it in the lens or the technique?</p>

<p>I have done this but with a full frame DSLR (A 1Ds Mark II) The problems will be that you are very limited to what focal lengths you can use and the shift range: the mirror box on the DSLR and how close you can bring the front and rear standards together are the reasons. You wil lalso get viewfinder balckout very quickly.<br>

A better solution is to use tilt shift lenses shifted to near maximum and shoot frames at each click stock when rotating. </p>

<p>See this thread: http://www.photo.net/large-format-photography-forum/00EZ5w?start=20<br>

http://www.ppmag.com/web-exclusives/2006/05/review-studiotoolstm-stsmodel.html#more</p>

 

<p>Why not put a 120 back on the Sinar? Then everything will work together. I use mine with a 65mm Super Angulon and a 6x9 back for architectural.</p>

<p>Allen, I do a lot of HDR, so I would rather shoot digital than film. Nothing against film, just not the way I work. Besides, if I have a 4x5, why not just shoot that for film? A while back I was going to do a MF back, but sadly I don't have the 3k+ I need to get a decent MF back at the moment.</p>

<p>Bob, I don't know a VR system built to simulate movements you get from the front standard. And I would think, that as long as you are turning the front of the lens, you are altering the perspective and creating a "curvature". However, most software can correct the parallel line issue, so just strike that one to my own stupidity. Really, it is those movements that I am after.</p>

<p>I already have one of the older single row pano heads from Manfrotto, and it works great with longer lenses, but I don't like the distorted feel I get with shorter lenses. I don't know the right technical terms for this situation, it just doesn't feel right.</p>

<p>Ellis, I missed that thread as I was hunting around. Look forward to reading it. I think I need to double check, but the Canon TS lenses may be a bit more versitile than the Nikon PC lenses. Although, a PC lens + a RRS rail could be an interesting option. It works for a single image capture, but I also have a desire for much more resolution than my puny little 10MP can provide without stitching. Not sure if it would work, probably would depend exactly on how you move the lens compared to how you slide the camera.</p>

<p>Interesting little quote from Ellis in the linked thread:</p>

 

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<p>A similar mosaic image could be made with the Canon EF 24mm T/S lens but of course by shifting the lens position you change the point of view which will change the depicted spatial relationships in a three dimensional subjects</p>

</blockquote>

<p>This basically sums up my main goal right there.</p>

<p>Zach,<br>

I have been experimenting with attaching a Sony NEX to a Toyo 45G. You can see both the current rig and resulting photos (including a large panorama) using a Mamiya 50mm lens at:<br>

http://www.flickr.com/photos/9476880@N02/sets/72157626112111247/<br>

Earlier configuration with a Nikon D70 at:<br>

http://www.flickr.com/photos/9476880@N02/sets/72157621949266496/<br>

Good luck on your project.</p>

<p>Paul, thanks for the input. Why did you end up with the Mamiya lenses? Do you use the rear rise/tilt and shift at all or are you just shooting the center?</p>

<p><em>" Why did you end up with the Mamiya lenses? "</em></p>

<p>He needs the anger from the small image circle^^</p>

<p>Mag, depending on how much rise/fall/shift he has on the back of that 45G, he may not be able to get the entire image circle anyways. I need to do some math and figure out how big of an image circle I would need on an F1 to determine exactly what I need to start. The answer may surprise us all.</p>

<p>Zack,</p>

<p>I used the Mamiya MF lens because of its retro-focusing design. I have problems with using my 90mm Schneider LF lens. Also, older LF lenses do not generally have the optical resolution needed for digital capture. There is very little movements. The long focal-plane to flange distance of the RB67 makes it ideal for using wide angle lenses (e.g. the C 50mm). I am able to use the back standard to cover over 7cm across for panorama, more for MF that covers a 6x9 area. This is the better approach because the lens does not move, thus does not introduce any parallax. The C 50mm seems sharp enough at both the center and edge, but it seems to suffer from field curvature. I need to experiment with the front floating lens to correct some aberration, which seems to have a different characteristics for digital than film.</p>

<p>In theory, the 6x7 area can produce a stitched image of 160mb+ with the Sony NEX. I have done panoramas vertically and horizontally, so I know it is possible to produce such a large image. It just takes some work.</p>

<p>Good luck on your efforts.</p>

<p>Thought that would be the reason. RB lenses are fairly cheap, so I could get two or more for the price I was going to get the digital Schneider for. And for that matter, any 6x7 lens should give me about the same coverage, so that opens up a whole new world of lenses. Just have to figure out how to mount them to a recessed board. Did you use a pre-made board for yours, or did you build it?</p>

<p>I either cut the right size hole in an existing lens board or make a custom wood one. I have made my own recess board, but you don't need one with the RB67 lens, just a bag bellows.</p>

<p>Got it. Thanks a ton!</p>

<p>since then I have done some work with shifting Tilt /Shift lenses and stitching. Attached is an example</p><div></div>

<p>You shift the film plane not the lens. I hope that's just a typo in the image caption. The lens needs to remain stationary because it is casting an image circle on the film plane and you move from spot to spot on that plane to capture what ever part of the image you want.<br>

I also shoot a lot of stereo and a small movement of the lens introduces an entirely different image to the film plane. A couple of inches of movement creates a wonderful stereo pair. If your image is of a flat row of objects across the field of view there won't be much of a problem. But, if it's a layered image with objects at different distances you will start seeing drastic errors with the relationship of near and far objects.<br>

You need to invest in a lens that can give you the image you want on the ground glass, then capture that image with your camera. This will give you full use of the front movement without introducing distortion. Since Sinar tilts the whole front standard to gain tilt, and there is no way to move the lens and remain focused, Moving the rear standard works best here also.<br>

Have you considered making a two axis sliding mount to hold the digital camera. They have been used for over a century to make large sheets of film with multiple images in rows. They move the film around capturing the central image in a small masked hole. They would also move a camera around to capture different parts of the large image. I have one with my 5x7 Berk and James. It was set up for two side by side images. By changing the detent points and removing the mask it would take a nice ordered row of images quite well. Add a couple vertical positions that the camera can slide into and you have a nice batch of images to stitch without the worry of moving the camera. You might consider picking up a 5x7 back to give yourself a bigger area to work out tooling. It will also give you extra stretch in those great architectural moments. A 90mm Super Angulon will work well with the 5x7 if you aren't using the image to the corners. I shoot a Sinar F with a Noma 5x7 back with a 90mm on a regular basis.<br>

It isn't hard work getting the lines all parallel before you make your shot. Just look at your bubbles and set them vertical and level for architecture. Why not start with a file with the lines as close as possible to a row of pixels. You were correct to want to get lines parallel. Why start with a messed up file, even if it is easy to correct.</p>

 

<p>My bad: it isn't aa typo but I picked the wrong photo!<br /> The attached was also shot with a EF Canon 17mm f/4 TS-E on an EOS 1Ds Mark III. it is a "daisy" stitched panorama from 15 individual frames. Starting with the lens centered, it was then shifted outwards and then a frame was shot at each click stop around the circle.</p>

<p>PTGui 9.0.3 was used for the stitching and output in blended and layers mode. In the the blended image I noticed there was a glitch down in the lower right corner. The appropriate two layers were opened, copied and added to the blended version. A mask was created for each layer and the mask painted with a black brush so that only the areas that corrected the glitch were added to the blended composite. There is still a small glitch up at the far end of the bannister on the right but I was working quickly on a reduced size version for this example.</p><div></div>

<p>This is the center of the daisy, the frame shot with the lens centered (not shifted).</p><div></div>

<p>Allen is correct that the ideal approach is to move the camera along the film plane rather than shift/rise the lens. In practice, I am not sure how much of a difference it makes, and certainly software are able to stitch despite parallax and image curvature. Sometimes not, which has been my experience. That is one reason I started experimenting with mounting a DSLR and later a mirrorless compact on the back of a large-format camera, which produce the closest thing to apparent seamless or glitchless final panoramas. But, the hybrid camera is a much, much more difficult piece of equipment to use than a DSLR with a T/S lens. (I have the Nikon 24mm tilt/shift.) Moreover, the digital cameras out resolve all but the most expensive LF and MF lenses, although overall I think one can get more usable large images from the hybrid because down rez'ing recaptures some sharpness. So, there are trade offs to each approach.</p>

<p>Ellis, is it just me, or did the shape of that wall in your two images alter slightly between the regualr shot and the daisied shot?<br>

Allen, I am using two axis sliding back in google as a search term to find what you are talking about, but to no avail. Can you give me a hand and get me to an example, or better yet, the instructions for building one. I can look and see how feasible it would be to design my own, maybe as a phase II kind of thing.</p>

 

<p>Hmm....should I sell my 10.5mm Fisheye to help bank roll this?</p>

<p>Zach, the rear standard on a 4x5 will allow you to move along the two axes (rise/fall and shift). As for the cost of the project, shop carefully. My last Toyo (I have three: one for film, one for the hybrid, and one for parts) was about $150, with lens board, film holder and bellows. Had a minor problem in the focusing rail that I fixed. My cheapest Mamiya lens was $10, most expensive $90. They were "as is", but worked perfectly fine for the hybrid. Just make sure that the aperture works and the lens is clean. Add another $50 to $75 for misc parts. The secret is to shop carefully on ebay, KEH and craigslist. Good luck.</p>

 

<p>Sinar F1 on KEH is about $250, so that was the starting point. After that, it is hunting around. I could straight up sell my Fisheye to KEH for $349, I think, or try and CL or Ebay it.</p>

<p>There isn't much on CL around here, so finding stuff is a bit hard through there. Once and a while a gem shows up.</p>

<p>Ellis, I envy you that 17mm TSE! To get the same coverage with an LF lens would mean what? A 55mm lens to cover 5x4 and then some? Either way you're looking at a fair cost in glassware.</p>

<p>I agree that the "proper" way to do this is to keep the lens still and move the camera/film/sensor plane. So what's needed for a DSLR solution, I feel, is a lens clamp that holds the lens fixed in space while the camera can be shifted and rotated behind it. How about a simple padded worm-drive hose clamp (Jubilee clip) welded to a 1/4" nut? Or at least something along those lines.</p>

<p>Once you start to stitch outside of the lens coverage circle things go (literally) pear-shaped, and you no longer get a rectilinear representation, unless you can move the whole camera parallel to the subject. I once tried this in order to get a rectilinear pano of a narrow street of shops. The camera was placed facing each shop front from the opposite side of the road and the several negatives stitched together. It was a nightmare stitching job that I wouldn't want to do on a regular basis.</p>

<p>"The camera was placed facing each shop front from the opposite side of the road and the several negatives stitched together. It was a nightmare stitching job that I wouldn't want to do on a regular basis."<br>

At the nodal point?</p>

 

<blockquote>

<p><em>A 55mm lens to cover 5x4 and then some?</em></p>

</blockquote>

<p>a 47mm f/5.6 Super-Angulon XL will do it -- and you won't need to shift!</p>