Let's begin a discussion on technical cameras

[Don Libby]

Our studio has been shut down the past couple days due to some remodeling so being bored and looking for something else to do I decided to do yet more testing of movements using my Cambo WRS, IQ180 with the 40HR lens. Attached to all this was a Lee filter hood. First I shot LCCs using the Capture One LCC plate which fits inside the filter holder. The LCCs were shot, center, 5, 10, 15 and 20mm left and right with the 180 set in a vertical position.

I also did a 2-shot pano with the back horizontal with 15mm movements.

15mm - Horizontal 2-shot capture ending up with a 44.619x21.708 (@360 dpi) or 16,063x7815 px

This is a 15mm - Vertical 37.344x28.797 (@360 dpi) or 13,444x10367 px

The final test was to see just how wide I could go in a vertical mode. 20mm 42.808x28.761 (@360 dpi) or 15,411x10,354 px.

I went lazy in processing the files; using C1-Pro I did a lens correction then LCC on each file before sending them to PS-CC where I stitched then and saved the finished files as jpegs. No cropping and no other processing was done. I'm very impressed with the quality of the LCC files and had thought to include them here but then again I'm lazy today. (I'm also stuck using my laptop instead of the studio computer).

One final thought is that I shot all these tethered to a SP3.

This is making it harder to justify a wider lens other than I want one....:facesmack:

 

[Dogs857]

This may be a little left field but......

It was raining here again today so I started doing some math and other things putting together the ultimate technical landscape kit for my taste. I have always been a big fan of 617 cameras and so tend to crop a lot of shots to the 1:3 ratio. For me this usually means flat stitching and then cropping in Photoshop. So I started wondering what a 617 digital camera might be like.

If you took existing MF sensor technology and lenses I reckon you could build the following.
I have taken all my measurements off the IQ160 as it is a bit friendlier to shifting than the 180 seems to be, and I need a wide sensor.
Sensor Size would end up being 103.8mm x 34.6mm
Pixels in play would be 17318 x 5773 which is bang on 100MP
This would fit nicely in the 60XL, 90HR and 120XL lenses so you don't need to make anything new.
I'm sure someone could build a body to take the back (something with nice wooden handles) with 5mm rise/fall
Print size at 300ppi would be 146.7cm x 48.9cm (57.7" x 19.2" for the metrically challenged)
You could still crop a 3:4 shot out at 44.4MP and a 2:3 shot at 50MP.

I know there are scanning backs out there, but this would be a one shot device that uses existing image circles to achieve its goal. Obviously this would depend on the usability of the lenses involved, not owning any of them myself makes it all theoretical. Plus using existing sensor technology all they would have to do is make it wider, how hard can that be

What do you think, anyone else want a 100MP 617 digital back??

 

[dchew]

Dogs,
I have come to like the 9:4 (2:25:1) ratio the STC provides when shifted 18 mm each way. It could very well be a case of "be happy with what you have," but I think it is more than that. 6:17 is great for printing and getting larger prints out of a one dimensional limit on our printers, but I feel it is too wide for my taste also it is not conducive to viewing electronically.

18mm each way produces roughly a 90x40mm, using about a 98mm image circle that doesn't stress even the IQ180 with most lenses. With the IQ180 that's a 133mp image, no cropping and a ratio I've become quite fond of.

Dave

 

[Digitalcameraman]

Dave,

What lens are you getting to move 18mm and doing these pano type shots?
So instead of turning the chip vertical and doing like 15mm each way to end up with an aspect ration similar to a 4x5, you keep the chip landscape and shift 18mm left, 18mm right to get this aspect ration?

Dogs,
I have come to like the 9:4 (2:25:1) ratio the STC provides when shifted 18 mm each way. It could very well be a case of "be happy with what you have," but I think it is more than that. 6:17 is great for printing and getting larger prints out of a one dimensional limit on our printers, but I feel it is too wide for my taste also it is not conducive to viewing electronically.

18mm each way produces roughly a 90x40mm, using about a 98mm image circle that doesn't stress even the IQ180 with most lenses. With the IQ180 that's a 133mp image, no cropping and a ratio I've become quite fond of.

Dave

 

[Dogs857]

Dogs,
I have come to like the 9:4 (2:25:1) ratio the STC provides when shifted 18 mm each way. It could very well be a case of "be happy with what you have," but I think it is more than that. 6:17 is great for printing and getting larger prints out of a one dimensional limit on our printers, but I feel it is too wide for my taste also it is not conducive to viewing electronically.

18mm each way produces roughly a 90x40mm, using about a 98mm image circle that doesn't stress even the IQ180 with most lenses. With the IQ180 that's a 133mp image, no cropping and a ratio I've become quite fond of.

Dave

Yeah you always want what you don't have

I quite like the 6:17 ratio myself, but also find 2.25 - 2.5:1 ratio suits some things as well. I was just spitballing one day about what could be achieved.
I certainly couldn't afford such a sensor if it was released tomorrow anyway

 

[jagsiva]

I do this quite often with my IQ180 and Arca kit. I use the Rotaslide (+/- 22mm and +/- 15mm on the body). The body has +20/-30 rise fall in addition to this.

120ASPH - I can get a 40x120mm.
90HRSW/60XL - 35x105mm
32/40HR - 40x80mm

With the 90HRSW, I could push a little wider if there isn't anything too interesting in the corners.

 

[dchew]

Chris,
Yes that's right. Two shots each shifted 18mm results in a 89.7 x 40.4. It is about a 98mm image circle if I remember right. I do that a lot with the sk150 and the 90hrsw. Works fine with the sk60 too, but I don't generally do wide angle panos. You do have to mount the 34mm adapter on the back when shifting with the 150 (not on the lens) or it will vignette.

Probably wouldn't work so good on the 40hr. 15mm is more my limit with that.

Dave

Dave,

What lens are you getting to move 18mm and doing these pano type shots?
So instead of turning the chip vertical and doing like 15mm each way to end up with an aspect ration similar to a 4x5, you keep the chip landscape and shift 18mm left, 18mm right to get this aspect ration?

 

[Don Libby]

Went to Lake Tahoe with Ken Doo and Dave Gallagher last week. What I wasn't expecting was to end up using a Leaf Credo 50 wide spectrum on my Cambo. I ended up using it for the last 2-days of Tahoe and was allowed to keep it a while longer.

What has shocked me was how much I enjoyed shooting the 50 WS. Sadly I became ill since returning home and was unable to use any more and must return it. As much as I enjoy my Sony A7r WS using the Credo 50 WS is light years more fun and fulfilling. I'll be sharing more information and images as I recover so stay tuned.

Don

 

[Pemihan]

Went to Lake Tahoe with Ken Doo and Dave Gallagher last week. What I wasn't expecting was to end up using a Leaf Credo 50 wide spectrum on my Cambo. I ended up using it for the last 2-days of Tahoe and was allowed to keep it a while longer.

What has shocked me was how much I enjoyed shooting the 50 WS. Sadly I became ill since returning home and was unable to use any more and must return it. As much as I enjoy my Sony A7r WS using the Credo 50 WS is light years more fun and fulfilling. I'll be sharing more information and images as I recover so stay tuned.

Don

I look forward to your full report on the 50 WS Don!
Get well soon!

Peter

 

[Don Libby]

This will have to do as a teaser (at least for now).

Sunrise at South Lake Tahoe, Cambo WRS 40mm HR and Leaf Credo 50 Wide Spectrum tethered to a Surface Pro 3. Can't find my notes on this one so can't tell you the f/stop however it was captured in full spectrum, 1/30 ISO 100. The file was opened first in C1 Pro for initial processing.

Any future images will be posted in the tech cam image thread.

Don

 

[Smoothjazz]

A question for Dave, and the group;
Just curious to know when using a Tech camera, how do you decide when making a panorama, whether to shift for a 3 pano stitch, versus just rotate the camera on a panoramic tripod head, and take 3 images to stitch. I have wondered if there is any advantage of one method over the other. This could influence my next Tech camera choice.

 

[Dogs857]

Really either is a viable option.

Me I flat stitch as much as possible, probably 98% of my shots.
Flat stitching means everything just lines up, and I know roughly where my crop lines and edges will be when I set it all up. I always crop to one of 2 ratios, 1:2.5 and 1:3.

 

[Paul2660]

With the tech camera, I tend to always 3 part shift, 15mm L, C, 15mm Right or
20mm L, , so C 20mm R, depending on the lens. I always shoot the center shot even though you can make the stitch from just R and L shifts, but the center is the best of the lens, so I always shoot it. As pointed out by Jeff, the shots will line up perfectly, every time. Not always the case on the other option even if level and nodal, if you are panning a wide lens, which I tend to use.

IMO, you won't really get a true 1:3 pano doing this unless you crop the image.

I also will sometimes mess with getting fully level, setting my nodal point and then stitching 3 or 4 shots, as this gives the best optical quality, since you are staying in the center of the lens and the LCC correction tends to be the best.

The huge advantage I feel you get with the tech and shifting, is you are moving the camera back, not the lens. So you don't have to worry about being level, nodal and all of that. I would say 90% of my shots are set up where I can't be level easily so I will stitch. Plus, sometimes I will use a CL-PL and ND or just a CL-PL and the stitching makes working with the CL-PL easier. If you pan a camera across a wide shot, the CL-PL will need to be adjusted as you move across the scene, not so with stitching.

Paul Caldwell

 

[Smoothjazz]

A good point about the polarizer- I had not considered that aspect for stitching shots. It could be very difficult to merge 3 images with different polarization.

 

[jianghai]

I'm pretty inclined to OCD tendencies, so it really bugs me when there are seams in the stitching.

For me getting the perfect nodal point would be (is) infuriating, not to mention set up time, and dealing with panning clamps that are not machined level with the base (i.e. after leveling the rotation of the panning clamp is not 100% level) etc etc.

Anyways in order to avoid those annoyances during stitching I always shift the back, or if using my TS-E I've even gone so far as to buy a lens collar so I can shift the body not the lens. Shots line up perfectly every time, minimal post fixing.

One more thing to bear in mind is that there are obvious limits when doing flat stitching (angle of view limitations) whereas nodal panoramas can be essentially unlimited, and provide a different perspective from flat stitching.

 

[Geoff]

From geometry, the two are quite different: nodal panoramas are essentially radial, as if you stood in one place and turned around. Shifted panoramas are more orthogonal, as if an architectural elevation was done, all with one perspective.

That said, it may be that panorama software makes nodal images more similar than not. Has anyone done a comparison?

 

[Paul2660]

From geometry, the two are quite different: nodal panoramas are essentially radial, as if you stood in one place and turned around. Shifted panoramas are more orthogonal, as if an architectural elevation was done, all with one perspective.

That said, it may be that panorama software makes nodal images more similar than not. Has anyone done a comparison?

You make a good point, and the modern software allows you to get away with an awful lot. The real key is will the human eye see the warp? On a natural subject most times you will not unless it's something like Yosemite. Where I shoot I can usually make it work. In fact the new stitching in LR CC is very impressive, and what's so wonderful, even when stitched, LR treats the final image as a raw until exported. Huge potential IMO.

Other tools are ptgui and Kolor's but which I used at times for traditional panos as they give you more options for stitching solutions.

Since all my tech stitched images are worked in C1, I then export and most times just use CC as it's blending is exceptional most times especially with troublesome skies which happens a lot for me with the IQ260 and 40mm.

Paul Caldwell

 

[Geoff]

Paul -
So do you use nodal panoramas or stitched? Or both? Preference?

 

[Paul2660]

Hi Geoff,

When using the IQ260, I am almost always on a tech camera, so I will most often stitch. However if I have a lot of a solid blue sky, no clouds to break up the sky, I will try to go nodal since C1 IMO does not do a very good job on the LCC correction with the IQ260/40mm Rodie with a lot of blue. I still get quite a bit of red cast/magenta cast on shift of 15mm.

Since I started using Ken's tethering solution, I pretty much always have my nodal rail now, so when I think I can get away with it, I will also setup for a nodal. To me the setup is not that hard, I just try to get the middle of lens over the center of the tripod (per the instructions at RRS). The real key is being level. These types of shots will work together quicker sometimes due to less color cast.

I will also say, that my 40mm when shifted to 15mm shows a good bit of mustache distortion and the 32mm Rodenstock I tried was even worse. The distortion shows up as objects being towards the edge of the shift being shorter and fat. To me very hard to correct and the Alpa tool IMO does nothing for this. I notice it on tree trunks mainly where towards the edge of the frame they get a bit fat. But I really did not realize how much was going on till I worked around a Dam on the Arkansas river, which had a bridge on top. The amount of mustache on the bridge piers was to me pretty excessive on shifts. Most don't seem to mind it and I may have a 40mm that's just worse than others.

When I am working in low down I almost always work non nodal. It's just a lot easier to setup a shot. It's hard enough to get down low to the ground now for me and trying to see the screen on the camera and level everything makes for a lot of work, plus many times the level perspective is not what I want. The image below was taken in a 3 part 15mm L, C 15mm R series of shots with my 40mm and is about the max pano you can get. I have cropped into this shot just a bit top and bottom to get it closer to a 1:3 ratio.

When I shift, I tend to keep the back horizontal (unless I have the 28mm on) and when I work Nodal, I tend to rotate the back 90 degrees to the vertical and then take around 5 to 6 shots across the frame. The vertical format seems to have less distortion, as I am mainly working with wide lenses.

Paul Caldwell

 

[Kolor-Pikker]

I know there are scanning backs out there, but this would be a one shot device that uses existing image circles to achieve its goal. Obviously this would depend on the usability of the lenses involved, not owning any of them myself makes it all theoretical. Plus using existing sensor technology all they would have to do is make it wider, how hard can that be

What do you think, anyone else want a 100MP 617 digital back??

So basically a one-shot version of the Seitz 6x17?

Would need a lot of sensors stitched together for something that big, but then you have the problem of running into tiling, made especially vulnerable by the wide field of view.

You can't just take an existing sensor and "make it wider" because a stencil of the whole sensor has to be projected onto the wafer at once, meaning that the etching device actually has to be large enough to do so, while being able to etch sufficiently small circuitry for it to work. Sony's 33x44mm CMOS is the current limit in single tile sensors.

With regards to aspect ratio, I actually find the 4:3 aspect of MF to be much more enjoyable then old 2:3, and stitching two horizontal shots is often more than enough if I want a pano. Certainly though, it might be interesting to "see" in 6x17 during the shot, I'll give you that.