Calculate this

Bart_van_der_Wolf said:

As a veteran in stitching (I started by stitching film scans before digital cameras became common), I have to say that I've never heard about a "Brenizer method" before. I somehow doubt he 'invented' the method, although he may have helped to make it popular. Perhaps you used the term in the latter sense.

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If you read carefully, you will find out that I nowhere wrote that Ryan Brenizer invented the so-called method known under his name.

Doug Kerr said:

Hi, Asher,


Thanks for the concise summary of this "scheme".

As Jerome points out (and of course I paraphrase), this performs in the most direct way the dissection of a larger format image into multiple smaller format images, which (if digital) we can then combine using available "stitching" tools.

As Asher points out, once we take this approach, then the overall optical properties of the "rig" are identical to those of the same camera with a full-frame film holder ("full frame" here meaning, as it ought to always, the normal largest frame size of the camera "chassis" involved). [I assume here that the journey of the small camera fully maps the full frame of the base camera; perhaps in practice it doesn't exactly.]

Thus, with a certain lens in place, depth of field considerations (based on criteria pertaining to the size of the composite image, of course) and the matter of providing for the "plane" of perfect object focus to be located and oriented as we need, pursuant to the principles of Scheimpflug, using the movements of the base camera, work just the same way they would with that camera (and lens) with a full-fame film holder.

Very clever, and I would assume very workable.

Best regards,

Doug

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Now that LV is almost standard I suppose the concept is far more workable. The idea of the Camera Fusion is that you compose, tilt, etc on a provided ground glass at a similar (though by no means the same) plane of focus and then attach the DSLR, focus accurately and stitch. The problem was when I had it and LV was still just a dream that it was a nightmare trying to focus due to the mirror box shading the viewfinder a great majority of the time coupled with the low resolution of the lens relative to the tiny portion you were seeing through the viewfinder. Now with LV you can of course focus with much greater ease and accuracy. I remember when the G1 was announced exitedly emailing the company asking if they would be making a version for 4/3 as now it would be so much esier to work with, no mirror box shading plus quality LV on a decent screen! You have to keep in mind also that with a APS camera you're shooting some 80 frames and 50 or so with FF. The movement on the back of a LF camera due to the balance means you give the setup a few seconds to stablise after each movement and all in all, if you're shooting in changing light, forget it! The stitching markings are for APS so you need to pay attention when using FF (not recommended due to more mirror box shading anyway) and when you have some 120 megapixels detail, focusing and standard alignment is hyper critical. The frame provided is 6X12, already a crop from 4X5 and if you crop that to a more standard ratio your lenses will have a 1.5X crop factor. You will be using a handmeter and have to know your sensors limitations as HDR with that many files isn't for the faint hearted!

It's a very well made and machined solution and the GG/Stitching adaptor is elegant. The customer service is more than incredible, I had perhaps 80 email contacts with them as they helped me out, held my hand and in general kept in touch to see how I was doing. They even bought it back off me for a substantial percentage of the new price when I decided it wasn't for me, eventhough I'd filed off a tab which was interfering with my tripod head. When I got it right I have NEVER seen IQ which even approaches the results I got using it for resolution coupled with the most wonderful tonality icluding comparing spherical stitching of higher megapixels as I've been doing now, no doubt due to the LF lenses, even the new P1 IQ180 files I've seen don't come close to the rendition of tonality. Think 8X10 with the most wonderfully smooth lens on the creamiest emulsion possible. It is however a very specialised tool, designed for studio use and I wouldn't advise anyone to buy before a full and comprehensive look into what is involved so that they are happy with the results and don't suffer buyer remorse due to a lack of awareness of what a system like this involves. I'd say exactly the same about any intricate camera system such as an Alpa with digital back.

Ben Rubinstein said:

Now that LV is almost standard I suppose the concept is far more workable. The idea of the Camera Fusion is that you compose, tilt, etc on a provided ground glass at a similar (though by no means the same) plane of focus and then attach the DSLR, focus accurately and stitch.

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I am now using LF more regularly but for my own art and hobby, not for doing anything for anyone else's wishes and needs. For that I prefer the tool with the least effort.

However, since I already have all the lenses for the work and the Camera Fusion back, it's easy at any time to use this clever system if it fits the bill.

For detail rich, high resolution images, with enough money, of course, (one can bypass the angst of thinking and real life) and just grab a top of the line Phase One, Leaf or Hasselblad. They won't disappoint!

We can, however, (and more than a few of us do), meet the need for detail-rich quality with LF film or else stitching with smaller sensors! As this thread discussion brings out, there can be important differences in how the planes are built with different stitching methods. Each job has specific needs: time frame, budget, end resolution needed, rectilinearity requirements and so forth. We're lucky to have so many choices.

Asher

I forgot to mention that the LF + Camera Fusion setup at the time required a Lowepro Pro Trekker bag (their biggest), I'm just not physically able to do that anymore, especially when the equivelent is a small crumpler shoulder bag.

Hi, Ben,

Thanks for this nice detailed discussion of the Camera Fusion rig.

Ben Rubinstein said:

Now that LV is almost standard I suppose the concept is far more workable. The idea of the Camera Fusion is that you compose, tilt, etc on a provided ground glass at a similar (though by no means the same) plane of focus and then attach the DSLR, focus accurately and stitch.

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I had thought that the intent was that the ground glass and the focal plane of the digital back would be in the same place (recognizing of course that there would some discrepancy owing to tolerances).

Do you mean to suggest that the expectation is that the two planes would only be approximately equivalent? Or are you merely intending to call attention to the fact that in reality there would be some discrepancy?

I haven't looked at the Camera Fusion instructions or whatever to see what provision there is (if any) for bringing these two planes into coincidence in an actual installation.

Of course, certainly focusing with the aid of Live View would be more precise. On the other hand, I would think that when dealing with a "Schemipflug" setup it would also be useful to be able to visualize (even if less precisely) the focus across the entire (large) frame, as via the ground glass.

What do you mean when you say the actual overall frame is "6x12"? 6 x 12 inches is too big, 6 x 12 cm is pretty small. 6 x 12 small frames doesn't seem to work out right either (either for 36 x 24 mm frames or 22.5 x 15 mm frames ("APS-C" - ugh)).

Aha! The Camera Fusion Web site says that the range of movement is 12 cm horizontal and 6 com vertical. It seems that the "normal" orientation of the digital camera body is such that vertical corresponds to the long dimension of the digital camera frame.

But elsewhere, the site refers to the "full 6cm x 12 cm scanning area". Certainly confusing. My guess is that the first-cited passage is the correct statement.

The material there also says:

"The recess in the ground glass is accurately set to correspond with the location of the image sensor built into the DSLR body. This ensures that the image plane is consistent between the ground glass, and the capture device." "Recess" is a curious term, but is seems clear what they mean. But of course that is only the intent.

Thanks again for the great further detail.

Best regards,

Doug

Since it would be very difficult to bring the camera sensor forward to the ground glass position when mounting the adapter, I think the system works in the following manner:
-you focus on the ground glass, tilting the plane according to Scheimpflung
-you put the camera in place, the detector will be a few centimeters further back
-you adjust focus without changing the tilt angle.

Hi, Ben,

I'm still trying to makes sense of the numbers in the Camera Fusion setup.

If we consider a digital body with a frame size of 15.0 x 22.5 mm (you suggest that the "markings" on the CF rig seem to most directly cater to that) and a range of movement of the adapter of 6 cm x 12 cm, then the maximum possible covered frame (from a geometric basis only) would be 75 mm x 142.5 mm.

But how big is the actual image "window" that can be covered? The "4x5" film frame is approximately 93 mm x 119 mm.

Best regards,

Doug

Doug Kerr said:

Hi, Ben,

I'm still trying to makes sense of the numbers in the Camera Fusion setup.

If we consider a digital body with a frame size of 15.0 x 22.5 mm (you suggest that the "markings" on the CF rig seem to most directly cater to that) and a range of movement of the adapter of 6 cm x 12 cm, then the maximum possible covered frame (from a geometric basis only) would be 75 mm x 142.5 mm.

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90mm x 165mm, actually.

Hi, Jerome,

Jerome Marot said:

90mm x 165mm, actually.

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Well, my numbers were indeed in error - I had the horizontal and vertical travel reversed.

The coverable area is 135 mm (h) x 82.5 mm (v).

Sorry about the error.

Best regards,

Doug

The focusing plane of their GG is only approximate Doug, you have to focus from the camera for accuracy. It was the first thing that threw me when using the CF system. Their GG adaptor is for composition, movements and getting the focusing in the ballpark.

The stitching area is a 6X12 ratio, basically cut a 6X12 ratio out of the 4X5 ratio of the view camera.

Hope that helps.

Camera Fusion: Going "beyond the limits"

One thing that limits the system grabbing more laterally, (than the system is intended for), is the rim of the Eos front mount and the deep well to reach the Eos sensor. This outside edge will give a shadow to extreme lateral samples of the chosen image plane. So I do take more, but in smaller slices and then then crop the shadowed edge before assembling in APP or Photoshop.

Asher

Doug Kerr said:

Hi, Jerome,
Well, my numbers were indeed in error - I had the horizontal and vertical travel reversed.

The coverable area is 135 mm (h) x 82.5 mm (v).

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I may be mistaken, but I think that then the area (geometrically, ignoring obstructions) would be 150 mm x 105 mm ( 120 + 2x22.5 and 60 + 2x 15 ) and since we can turn the camera around at any point during the shooting process, we can take the max of these two calculations and cover 165 mm x 105 mm (ignoring obstructions from the mount).

You would end up with a cross shaped stitch but more than that and from someone whose used it, you'd have to be very very bored, that's a bleep load of frames!

Hi, Ben,

Ben Rubinstein said:

The focusing plane of their GG is only approximate Doug, you have to focus from the camera for accuracy. It was the first thing that threw me when using the CF system. Their GG adaptor is for composition, movements and getting the focusing in the ballpark.

Click to expand...

Of course.

The stitching area is a 6X12 ratio, basically cut a 6X12 ratio out of the 4X5 ratio of the view camera.

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So perhaps the actual coverable area of the large image is in fact about 60 x 120 mm (since the larger dimension of the "4x5" frame is about 120 mm).

With a 22.5 x 15 mm digital camera frame, that would completely covered by a tiling of 5.33 x 5.33 frames if there were no overlap.

That all makes sense (except for the way it is described on the CF site!).

Incidentally, the animated pix there make it looks as if in fact the movement is about 120 mm horizontally (along the short dimension of the digital camera frame) and 60 mm vertically (just as stated), so I'm still a bit baffled. Maybe that is just a coincidence.

That of course would not in any case at all lead to a conclusion of the area coverable (owing to limits on the "window" size).

Thanks.

Best regards,

Doug

Doug, you need something like a 50% (perhaps more can't remember) overlap with a FF camera due to the mirror box shading causing a black line covering a sizeable potion of the frame.

Hi, Jerome,

Jerome Marot said:

I may be mistaken, but I think that then the area (geometrically, ignoring obstructions) would be 150 mm x 105 mm ( 120 + 2x22.5 and 60 + 2x 15 ) and since we can turn the camera around at any point during the shooting process, we can take the max of these two calculations and cover 165 mm x 105 mm (ignoring obstructions from the mount).

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I think your algebra is not quite right - the two factors of "2" probably do not belong in it. (This is the well known "fencepost" dilemma at work!)

Here's a way to get to what I think is the answer.

With the camera in "portrait" orientation, and assuming the 22.5 x 15 mm frame size (15 x 22.5 in this orientation), starting with the camera in the far lower-left position, then if we moved it to the right by 120 mm (the available travel as stated by CF), its new right edge would be 120 mm to the right of its original right edge, or 135 mm to the right of its original left edge.

Similarly, if we then raised it by 60 mm, its new top edge would be 60 mm higher than its original top, or 82.5 mm higher than its original bottom edge.

Thus the area "mapped" with the camera in this orientation (theoretically, geometrically) would be 135 mm wide x 82.5 mm high.

If we did the same exercise with the camera in "landscape" orientation (assuming that the adapter allows this with the adapter travel axes still as is stated, we would get an overall area mapped of 142.5 mm wide x 75 mm high.

Best regards,

Doug

Hi, Ben,

Ben Rubinstein said:

Doug, you need something like a 50% (perhaps more can't remember) overlap with a FF camera due to the mirror box shading causing a black line covering a sizeable potion of the frame.

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Sure.

Best regards,

Doug

Hi, Asher,

Asher Kelman said:

One thing that limits the system grabbing more laterally, (than the system is intended for), is the rim of the Eos front mount and the deep well to reach the Eos sensor. This outside edge will give a shadow to extreme lateral samples of the chosen image plane. So I do take more, but in smaller slices and then then crop the shadowed edge before assembling in APP or Photoshop.

Click to expand...

Makes sense to me.

Thanks.

Best regards,

Doug

Hi, Ben,

Ben Rubinstein said:

The stitching area is a 6X12 ratio, basically cut a 6X12 ratio out of the 4X5 ratio of the view camera.

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Do we know where that 6x12 "boundary" comes from? For example, it would not seem to come from the limits of available movement on the adapter (12 cm x 6 cm) working together with the frame size of the digital body.

Just to make sure I am working with the right "vision", what is the orientation of your digital body?

Does your view camera have an inherent orientation of its native 4x5 frame (or could it take a film back in either orientation)?

Thanks.

Best regards,

Doug

Hi Doug. I've not had the adaptor for a few years but as far as I remember:

The camera body goes in vertical orientation to maximise usage. The adaptor, like a revolving back on a normal LF camera can also be attached in either horizontal or vertical mode. The aperture for stitching is 6X12 ratio and seems to go all the way to the edge of the camera's opening on the long side.

Doug Kerr said:

I think your algebra is not quite right - the two factors of "2" probably do not belong in it.

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You are right. I was mistaken.

I went out today and shot another image using the 50mm @f1.4, I got very very lucky the first time, now I'm learning about the nervous bokeh of this lens, it's in the highlights so it didn't appear in the previous image, you can't see it at websize but in the wall through the arch it's very nervous near anything close to a specular highlight and in other pictures it's just downright unuseable. The DOF is also too great as I had to step further away for the composition. Anyone want to sponser me a Rokkor 58mm f1.2 converted to Canon? $599 or so at todays prices and you can't focus past 25 yards or so due to the mirror, will be a nightmare to focus with my non live view 5D but I have to admit to still being very tempted. I'd take a Canon 50L if I won the lottery....

Hi Ben,

Glad to read that you are pursuing this further. Inspired by you, I have conducted a similar experiment myself yesterday. I chose a subject similar to yours, a wall with a couple of windows and an open door, which I have photographed at an angle (the distance of the camera to the middle part of the wall was roughly 3 meters). I have shot a single frame with the 24mm @f5.6, and I have shot roughly the same composition using the 100mm @f11. I ended up with 44 frames (due to the 50% overlap) which have then been stitched in a quick and dirty way (i.e. with some minor parallax/blending/stitching errors which need correcting in a final version). It was a very interesting experiment. The resulting image is some 22000x13500 pixels, which would be equivalent to a hypothetical digital sensor size of 141mm x 86mm (297 megapixels) using the same pixel pitch. The dof of the stitched image is lower than the 24mm image, as was expected. Looking at both pictures side by side on my 30" monitor, I can't say that I see an immediate difference in tonality (which was the main goal of the exercise). This should be because of the fact that both images are downsized to display them on the monitor. But I did not scrutinize them long enough yet. The proof of the pudding would be in the printing (at A3+ size or larger). However, since this was only a test picture without value I am not sure I shall bother printing it. Subjectively, the stitched image feels more robust and of course one can zoom into it almost indefinitely; the details are mind boggling. Never mind, I will let you know how and if this continues. If you want me to print your own pictures and send them back to you, I am gladly willing to do so; as I wrote earlier.

Thanks Cem, I've decided not to bother with the stitching route though as you say printing and large printing at that would be the only way really to compare.

Hi Ben,

Ben Rubinstein said:

Thanks Cem, I've decided not to bother with the stitching route though as you say printing and large printing at that would be the only way really to compare.

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I see where you are coming from and I fully understand. I have a lot of experience in creating multiple row panos and I know my tools well, so this exercise was not too hard for me to execute. Even then, this is only worth the trouble (due to the excessive effort required to shoot and stitch) if one really needs the extra resolution to print very large/wide.

Cem_Usakligil said:

Hi Ben,


I see where you are coming from and I fully understand. I have a lot of experience in creating multiple row panos and I know my tools well, so this exercise was not too hard for me to execute. Even then, this is only worth the trouble (due to the excessive effort required to shoot and stitch) if one really needs the extra resolution to print very large/wide.

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I've got experience with stitching as well but for the reasons you mention, even if you can stitch fast an easily, if you don't need to for your particular needs then it's unnecessary.

Another option is the Siggy 50mm which might suit and it's far cheaper. I have to do some research for what it looks like wide open. Anyone here got one?

Just bought a Pentax Takumar 50mm f1.4 on ebay last night ($70) after an exhaustive discussion on the alternative forum of FM as to what were the best options. I won't get it for a couple of months still (I have an operation on my foot on Monday) but I hope to be able to create art for you with it as soon as possible!

Hi Ben,

Ben Rubinstein said:

.... I won't get it for a couple of months still (I have an operation on my foot on Monday) but I hope to be able to create art for you with it as soon as possible!

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I wish you all the best with your operation next Monday. I hope all will go well and you will recover quickly. Don´t worry about photography, it is not as important as your health.

Cheers,

Hi,

I've been following this thread with great interest about the unique application of the tools.

Ben, I wanted to chime in and say I made your acquaintance at another site, where you were very helpful, and wanted to take the opportunity to wish you the best on your surgery and express my hopes for a speedy recovery!