Wednesday, August 2, 2017

Twin NX1000 Image Processing

In this blog I will describe how I process my images from the twin NX1000 rig with the z-bar. Same concepts apply for all twin camera rigs in the z-configuration (the left camera is upside down).

There are three steps involved:

  1. Transfer: Transfer the images from the camera to the computer.
  2. Match: Make sure that the images are matched in pairs (needed for multicoversion)
  3. Process: Read the left image, read the right image, align, save, repeat. You can do this manually or use multicoversion where you go have a cup of coffee, read the paper, and come back when everything is done.

Sounds simple, but the devil is in the details. It is always in the details. One complicating factor is that the images from the left camera are upside down.

Let’s look at these three operations closely:

Transfer Images

This is a common operation when using twin cameras for stereo, but I have found that it confuses some people. The confusion comes from not understanding computers (specifically Windows and the concept of folders). But that's a topic for another day.

First, I have the SD cards clearly labeled R and L, so there is no confusion which is which:




I also have permanent folders in my computer for the R and L images. I download the R images in a folder clearly marked for the R images and the L images to a folder clearly marked for the L images.

Here is how Windows Explorer (Windows 7) shows the two folders, when placed side-by-side. As you can see, the images from the L camera are upside down (click at the picture to enlarge).



Match Images

When shooting with twin cameras, occasionally one camera fires while the other does not. This happens with the Samsung NX1000 cameras if one is turned on while the other is off, or one is turned off while the other is on. For one reason or another, there might be extra (non-matching) images. When this happens to me during shooting, I immediately delete the extra image. By following good turning on/off procedures (see: http://drt3d.blogspot.com/2017/07/tips-for-using-twin-nx1000-cameras.html) I do not get many “orphan” images. But I always check to make sure the images are matched, before I do multicoversion because if they are not matched, multiconversion will fail.

You could match images using Windows Explorer (look at the picture above, you can visually see if there are any extra images, and delete them), however I like to use StereoPhoto Maker’s “Open File List” which is very similar to Windows Explorer, only better.

Note: Some people use and recommend StereoPruner. This is a program by Cyclopital3D that can be downloaded here: http://www.cyclopital3d.com/SUPPORT-AND-DOWNLOADS.html This program sorts the right and left folders to match the images.

Personally, I prefer to use "Open Image File List". Even if you use StereoPruner, you should become familiar with this SPM function because it is very useful.

SPM – Open Image File List

Open StereoPhoto Maker (SPM) and under File, select “Open Image file list”. This opens a window that looks very similar to Windows Explorer. I navigate the folders to find the L folder. At the top select “Open another instance”. This opens a second window. I navigate to find the R folder. These steps are shown here:




When everything is said and done, I have two folders (from SPM) side by side, the left sitting on the right (on purpose, so I can cross-view the images). Here is what I see:




I scroll down (both SPM folders scroll at the same time, nice!) freeviewing the images. This allows me to detect any extra images, which I then delete. When I am done, I have matching R and L images and I am ready to process them. The entire operation takes a minute or two.

Before we move to the final step, I want to make you aware of two things.

Image Numbering & Renaming:

If you look at the pictures above, you will notice that the image numbering of the R and L files is totally different. For example, the first image in the L folder is SAM_9600, while the first image on the R folder is SAM_1337. These numbers are off by 8000+. I have done this on purpose.

If you format new SD cards and reset the image number, then the numbers from each camera will be matching. Eventually, with errors and orphan images, they will drift away but not by much. If the  image names overlap, then SPM will not do multi-conversion correctly. In this case, you will need to rename one group of images.

You can rename the entire group of images (usually the L images) with SPM. While on the Image File List, go to “Edit”, then “Select All Files,” then right click and select “Multi-Rename”. This is a powerful function that allows you to do interesting renaming in the entire group of images. As powerful as it is, I prefer not to use it.

With previous twin camera systems, I tried to keep the file numbers matching. That was a pain. Now, I follow a different strategy: I have them as different as possible. By keeping a totally different file numbering, I do not have to worry about renaming images.

How did I change the file name sequence? I reset the numbering in only one of the two cameras at some point and this gets the numbers totally out of sequence. You can reset the file numbers via the menu, as I mention in this blog: http://drt3d.blogspot.com/2017/07/putting-twin-samsung-nx1000-camera-rig.html

Orientation Tag:

Notice that SPM shows the left image straight up but it has a number “3” in the corner. This number is called the “Orientation tag.” There are actually 8 different tags shown here:




By right-clicking at an image, you can select a different orientation tag. You can also select all the files (“Edit”, “Select All Files”) and change the tags on all of them (right click, “Set the Orientation….” (select what you like)).

Where does the orientation tag come from? It comes from the camera. If the camera knows that it is upside down, it marks the image with tag 3 “180 rotated”. Normally, all left images should have a tag of 3, but there is a situation where the camera does not know it is upside down. This happens when you point the camera up or down. In this case, the camera will give the file a standard “Original” tag because it is not aware it is upside down (think about this for a second…. when you point the camera directly up or down, there is no up or down camera). Because I shoot up and down often, I might select all files in the left folder and force the “3” tag before I try to match them. That’s just a detail, but it will eventually happen to you and you will wonder why an image from the L camera does not have the orientation tag “3” like the rest of the images. Now you know why.

Process Images

Processing the images can be done either manually (one at a time) or using multiconversion (batch processing, done by SPM).

For manual processing, go under “File,” “Open L/R Images,” find the left image, then find the right (the program prompts you). You then can do autoalignment (“Adjust”, “Auto Alignment” or press Alt-A). Save the combined and aligned image. If you move to the next image, SPM will automatically load the left image from the left folder and the right image from the right folder, because it is a clever program (so you do not need to navigate folders again).

Some people like to do manual processing like that. I prefer to do multicoversion. I don’t even attempt to view anything until everything has been aligned using multicoversion.

With multicoversion you go under “File” and “Multi Conversion,” and set up the dialog screen. You select “Independent (L/R)” as the Input file Type, tell the program where to find the R and L images, where (and how) to save the aligned image and anything else you want it to do. Here is how my multi conversion screen looks:




When I start multiconverion ("Covert All Files"), I always check the first image to make sure it is OK. If I see something wrong, I stop it, make corrections in the dialog screen and try again. You can check the aligned/saved images by opening another instance of SPM (you can run as many instances of the program as you like).

Everything sounds good. Except, when you load the image you just converted, you will notice that it is upside down!  It looks like this:




This is happening because SPM uses the name and orientation tag, from the L image to assign to the aligned image. Because the L image is upside down (orientation tag “3”) the resulting stereo pair will also have orientation tag “3”. To change this, after the alignment is completed, you can use SPM’s Image File List, select all the files and change the tag to “1”.

I have settled for a slightly different procedure: After I match the R and L images, I change the orientation tag of all L images to “1” (normal). Then, in the multiconverion screen, for the L image I select: “Rotation (180)”. The program then rotates the L image before alignment and the resulting image is not upside down because it carries the tag “1”. This is how my multiconverion screen looks (the only difference from the previous screen is the red square):




This completes my procedure. It is not very complicated and many steps are similar to when using any twin camera system. The only complication is that the left camera is upside down and it is the left image that SPM uses to give the aligned/saved image its name and orientation tag.

After a while, the processing steps become automatic. If anyone has any ideas or thinks they are doing this much easier or faster, I’d like to hear from you.



What’s in My Camera Bag II

In the previous blog (http://drt3d.blogspot.com/2017/07/whats-in-my-camera-bag-i.html) I discussed the contents of my camera bag from 2009 (“Last Great Film Vacation”) to 2016. I also discussed the reasons why one stereo camera is not enough for me. I need a variety of stereo bases and close-focusing abilities. So my camera bag contained a standard stereo camera (Fuji W3 or Panasonic 3D1, which also allows for hyperstereos and close ups), a twin camera rig for mild hyperstereos, a single camera for single camera 3D, and a Panasonic camera with the 3D lens for macro pictures.

Things changed in 2016 when I discovered the twin Samsung NX1000 cameras (see: http://drt3d.blogspot.com/2016/10/twin-samsung-nx1000-for-stereo-part-i.html)

Because of the normal spacing in the z-configuration (68mm) and good synchronization, this pair serves both as a normal stereo camera and also twin camera with a wider stereo base. It is also possible to use one camera for single camera stereo. This changed the contents and size of my camera bag, in a good way.

So, what am I carrying in my camera bag today?

The answer depends on the length, purpose and importance of the trip, vacation, outing, etc.  There are different levels:

  • Level 0: No stereo camera, just the phone for 2d pictures.

  • Level 1: Panasonic 3D1 camera. Even though this camera has a narrow lens spacing, it is easy to use, more compact than the Fuji and gives better pictures overall. If I only take one stereo camera with me, this is it.

  • Level 2: This is most often my “to go” camera bag. Here is a picture of it:





It consists of the following:


  • (Optional) Extra set of lenses. For general photography I use the 20mm (fixed focal length) lenses. I might carry other lenses, depending on what I plan to shoot. For example: 10mm (ultra wide), 16mm (wide), 45mm (shown here, for portraits or other pictures where a slightly longer focal length works better - if I carry a second pair of lenses, this is usually it). Any extra lenses are carried and stored as I describe in this blog: http://drt3d.blogspot.com/2017/07/lenses-for-twin-samsung-nx-camera-rigs.html

  • Panasonic 3D1 camera (and platform to carry it better). Great for close-ups, one of my favorite type of pictures.


  • Small supplies: Pair of extra batteries, SD cards, cleaning tissue.

  • All that stuff fits inside the LowePro AW bag. I like this bag a lot because it fits the completely assembled NX1000 rig, without having to take the handle off. There is room in the main compartment for an extra pair of lenses. Small accessories (batteries, etc.) fit in a little pocket at the top. The 3D1 and flash fit in the front pocket. There are also two straps on each side that can hold one or two longer twin camera bars vertically, see: http://drt3d.blogspot.com/2016/10/connecting-pair-of-twin-camera-bars.html




  • Level 3: In addition to Level 2, I might carry equipment for specialized use such us remote/high perspective photography, wide base hyperstereo, macro 3d, bird/wildlife/zoo photography, underwater photography.

Macro pictures: I carry a Panasonic GX7 camera with the 3d lens. Possibly two lenses with 0.5mm and 1.0mm extensions. Possibly one or two more compact flashes, or the Chinese double flash. This requires its own separate camera bag. I am working on finding a similar system that works with the Samsung cameras so I do not have to carry the Panasonic. Then I will be able to take macro pictures with less equipment.

Extensive Flash: If I plan to do more flash photography, I might carry more flashes, slaves, or related equipment.

Hyperstereos: I can shoot hyperstereos (up to 8 inches) with the Samsung rig, or non-synchronized hyperstereos with one camera and shift. If I am planning to shoot synchronized hyperstereos with a longer base, I will take one or two camera bars (two bars can be connected to form a longer bar).

Remote shooting: I carry an extra remote cable. I might carry the remote cable anyway, in case I want to separate the cameras longer supported on a ledge or even hand-held by two different people. Here is combination that allows for this:




High Perspective: In addition to the remote cable, I carry a pole for high perspective shooting. Here is an example (our house, with no tree to climb on sight):




Telestereo: For this I need longer focal length lenses plus a twin bar and possibly a tripod. Here is a possible outfit, consisting of 50-200mm zoom lenses:


Underwater Stereo: I have used a water tight camera bag for the Panasonic 3D1 camera in the past, with good results. This is flat and easy to carry. There is no excuse not to have one with me all the times if I am close to water or if there is a danger of the camera getting wet. Here is an example:






Adjustable Z-Bar for twin NX1000 cameras



I have designed and been testing a new adjustable Z-bar for twin NX1000/NX1100 cameras. The idea is similar to the first one I made earlier (my first bar, see: http://drt3d.blogspot.com/2016/10/twin-samsung-nx1000-for-stereo-ii.html) with a bit more attention to the details. The big attraction of this bar is that the stereo base is adjustable.

My friend, Ted Whitten, encouraged me to build this. At first, I was resisting, being very happy with the Werner body mount (http://drt3d.blogspot.com/2016/10/z-mount-for-samsung-nx-cameras.html). But then, something happened: I was ready to photograph the Memorial Day Parade in Brecksville. I had my cameras mounted side-by-side on my twin camera bar. I was standing under an electrical wooden pole. I looked up and saw the American flag, among transformers and electrical wires. The flag was being lit by the sun and everything looked just right. I wanted to lift my camera and take a picture of the pole and flag, but I could not, because I did not have a normal stereo camera. Using the side-by-side cameras would not have worked because I was too close to the subject. I needed normal camera/lens spacing. But I did not want to disturb my setting (it takes time to switch from side-by-side to the body mount), with the parade starting soon.

At that moment, I wished I had a z-bar with adjustable stereo base. So, I decided to build one. While Ted was visiting, we worked on a pair of bars. I figured out the basic dimensions and made two bars, one for Ted and one for myself. I tested my bar and it works fine. Now Ι got to the point where that’s all I use. So, I decided to start making this bar available for others.

Here is how I make the bar

I start with a piece of aluminum channel, 3" (tall) x 1" (wide) x 0.125" (3mm, thick). This material was recommended to me by Bob Karambelas, as described in the previous blog. It is the same piece I used for my first mount, and Bob for his, before we knew about the body mount.

I buy the aluminum channel in 24" pieces, and then cut it as shown in this diagram:




I cut a piece about 9 inches (230mm) long. I decided on this size because this is the length of two cameras touching each other. This way the bar will not spill out of the cameras when they are at their closest point.

I then remove two pieces, based on two important dimensions: 1) The center column is 20-22mm (I started with 20mm, now I favor 22mm). This column is in the back and does not cover the screen when the cameras are touching each other. It serves for both structural strength and camera alignment (when the cameras are close enough).  2) I leave a “step” of 8mm high. This is the step that the cameras rest on, and it helps to align them. This is tall enough to help align the cameras, but not too tall to hinder the two lower buttons or the screen.

After removing these two pieces, I need to drill holes and a channel at the top and bottom arms. I drill a hole 34mm from the center line and 15mm from the back step. These dimensions are dictated by the location of the camera tripod socket. My first design only had this hole and the cameras were at a fixed minimum spacing (touching each other). For this new adjustable design, I create a channel about 65mm long as shown in the schematic.

There is only one important detail left:  The distance from the top to the bottom is 76mm (total height of the channel) – 2x3mm (thickness of each arm) = 70mm. The distance from the bottom of the camera to the center of the lens is 33mm. So each camera must be raised by 2mm for the lenses to be aligned: 33mm + 2mm = 35mm, right at the center of the 70mm z-bar spacing.

To raise each camera by 2mm, I use a rubber washer for each camera. This is 2mm thick so it raises the camera, plus it holds the screw in place when the cameras are removed. The only issue with the rubber washer is that it hits the bar and the cameras do not slide smoothly. Also, it could be contributing to some misalignment. I am now experimenting with a piece of plastic. Check later for updates on this.

Update: I tried a piece of hard plastic and the cameras slide smoothly and the alignment is maintained (the rubber was being compressed, the hard plastic is not). It is a piece 20x60mm, with a hole drilled. It keeps the screws in place, raises the cameras, maintains good alignment. That's the way to go now.

The final product, with cameras mounted, looks like this:




(Note: This is my first bar… The back column is not straight. I am trying to do a better job since then )

Regarding the tripod sockets, there is one at the top and one at the bottom. I positioned these a bit off center so any screw thread from a tripod or camera grip does not hit one camera. At first, the z-bar was totally symmetric so either side could be the top or bottom. In my last batch I left one mount screw standard 1/4", but made the other one 3/8" for two reasons: 1) In case one needs a 3/8" mounting socket. 2) I added a 3/8 to 1/4 inch adapter. The adapter is made out of stainless steel so it is more durable than the easily deformed aluminum. I recommend using this side as the bottom.

Advantages of the Adjustable Z-bar

Compared to the body mount, this z-bar has two advantages:

  • Adjustable stereo base: This is a big one. One way to think about the stereo base is in multiples of the standard stereo base, which is around 65mm or 2 ½ inches. Let’s call this SB (Standard Base). The body mount only has one stereo base, SB. This z-bar goes up to 3xSB (about 8 inches or 200mm). 

Here is a quick way to get three different stereo bases, in case you like to bracket stereo bases:
  • With cameras touching: 1x SB
  • With one camera extended: 2x SB
  • With both cameras extended: 3x SB




  • The cameras can be removed from the mount very easily (unscrew the screws by hand). There is no need to take off the lenses and no tools are required.




Some other points:
  • Any shoe-mounted flash will work since there is no mount to interfere over the R camera.
  • The batteries and memory card can be accessed by simply sliding each camera out (see picture below).
  • There are plenty of standard 1/4" mounting sockets. One at the top, one at the bottom, plus the two screws that hold the cameras have a socket at the bottom. 
  • Finally, the 8 inches total stereo base of this rig is the same as my 12 inch twin camera bar. So, this z-bar simplifies things. Not only I do not need to carry the 12 inch bar, I also get all my stereo pairs in similar format, which simplifies processing.






Disadvantages of the Adjustable Z-Bar


  • It is not as well-aligned as the body mount. When the cameras are touching, alignment is good enough. When they are separated, alignment gets worse. I am working on this and will report back later, after I try other ways to raise the cameras by 2mm. This misalignment is not a practical problem for me because StereoPhoto Maker aligns the images very well.

  • It does not look as elegant as the body mount. I am still learning how to machine these. I am now working at making smoother curves, but these bars do not look nearly as elegant as the bars I have from Co Ekeren. But, they work.

One last note: The standard one-piece remote cable, is not long enough for this bar. I have ordered a set of longer cables that will work. But I have found advantages in using the twin remote: The main one is that you do not have to touch the cameras, so pictures with slower shutter speeds can potentially be sharper. 

My standard configuration for these cameras now is this adjustable bar, plus the twin remote.  Plus my favorite camera grip. This is how my rig looks right now (with 20mm lenses):






Wednesday, July 19, 2017

What’s in My Camera Bag - I

It’s an interesting question… What do stereo photographers carry in their camera bags? I have addressed this topic in two Stereogram Tutorials (a collection of 20 years of Tutorials, available for sale here: http://www.drt3d.com/ohio3d/stereogram/)
 
In March 2011 I published a 3 page Tutorial (click to enlarge):



You can download the entire Tutorial here: http://drt3d.com/tutorials/CameraBag1.pdf
 
In this Tutorial I describe three different times, my “Last Great Film Vacation” in 2009, a visit to New Orleans in 2010 with only the Fuji W1, and a return to New Orleans in 2011 with a lot more gear. Here is what I wrote:

 
Last Great Film Vacation (Summer 2009)
 
My last big film vacation was in the summer of 2009.  We went with my family to Orlando , FL.   For this vacation I carried a large camera bag loaded with film stereo equipment.  I had with me: Two RBT cameras (S1, X3), two regular SLR cameras (Pentax ZX-M) for single and twin camera hyperstereos, three pairs of Pentax lenses (20mm, 40mm, 100mm - these can be used with the X3 and the ZX-Ms), a heavy twin camera bar, a compact tripod, two flash units, cables, batteries, and plenty of film.  It was a heavy camera bag but I carried it with me without complaining, took lots of pictures and did very well in the Cleveland and Detroit stereo competitions the following year.
 
New Orleans 2010
 
In October 2009 I bought the Fuji W1 and in February 2010 we went (with my wife) to New Orleans to run the local marathon.  For that trip I only carried the Fuji .  I took hundreds of stereo pictures with the Fuji , had a great time and was pleased with the results.  Some of the types of pictures I took include:  1) Hyperstereos from the airplane, 2) Hypostereos at the Insectarium, 3) Pictures before, during, and after the race, 4) Pictures of the city during the day and night.
 
It was refreshing to travel with only one stereo camera in my pocket.  But that did not last long.  I soon discovered the wired Panasonic cameras, the Macrobox, and various attachments for the Fuji.  My photo camera bag started getting bigger and bigger.
 
New Orleans 2011
 
We went back to New Orelans in 2011.  This time I carried the following equipment:
  • Fuji W3 camera with ALA attachment and fisheye lenses.
  • Twin Panasonic TZ10 cameras, wired for stereo.
  • Macrobox with another pair of Panasonic cameras.
  • Panasonic GF1 camera with 40mm and 28mm lenses.
  • Flash, cables, memory cards, batteries.
 
I then continue to describe why I carry these cameras, how I use them, and to show typical results.
 
Two years later (February 2013) I published another Tutorial on the same topic:


You can download the full Tutorial here: http://drt3d.com/tutorials/CameraBag2.pdf
 
 
In this Tutorial I explain why one stereo camera is not enough for me. For my personal needs I have found that, to cover most photo shooting situations, I need the following:
  • A standard 3d camera for everyday use.
  • A single camera for hand-held hyper- (mostly) or hypo-stereos.
  • Two cameras on a bar for synchronized hyperstereos.
  • A close focusing camera/lens or attachment for close-ups/macros.
 
Here is how my camera bag looked in 2012:
 
 
 
This table is taken from this Tutorial and summarizes the contents of my camera bag though the three points in time:
 

 
This last Tutorial concludes as follow:

"Different people have different expectations and equipment requirements.  As the situation stands right now, no single camera can take the variety of pictures, from macros to hyperstereos, that I like to take, so I elect to carry 4 different systems when I travel.  I did this back in the good old film days and today in the digital era.  One advantage with digital is that I can fit all the equipment in one compact camera bag that does not weigh too much."


From 2012 to Today

There were only minor changes from 2012 to 2016. The GF1 and GF2 bodies were replaced with the GX1 and then GX7. I also stopped carrying the Fuji, in favor of the Panasonic 3D1. I used to say that I do not take any normal stereo pictures. It is either hypo-stereo with the 3D1 or hyperstereo with twin cameras.
 
I continued along these lines until last year when I discovered the Samsung NX1000 cameras. With these cameras I rediscovered the beauty of “normal stereo photography”, i.e. stereo photography with a base approximately equal to the spacing of the eyes (68mm for this rig).
 
Because of their normal spacing in the z-configuration and good synchronization, this pair serves as a normal stereo camera and also twin camera with larger stereo base. It is also possible to use one camera for single camera stereo. This drastically changed the contents and size of my camera bag. I will describe this in the next blog.

Tuesday, July 18, 2017

Lenses for Twin Samsung NX camera rigs

Lenses

In today's digital and phone photography, lenses are neglected. Most compact cameras use a zoom lens and the photographer, using the camera in auto-everything mode, is often unaware of the focal length or aperture selected by the lens. In many cases, maybe this is a good thing: The photographer can focus on the composition and not have to worry about technical details. But there are cases where it pays to know what the focal length and aperture is (or could or should be).

The Samsung NX1000 twin camera stereo system takes interchangeable lenses and also has a variable stereo base from normal to hyperstereo. It is a good system to experiment with different lenses.

There are three sources of lenses for the Samsung NX cameras:
  • Lenses made by Samsung
  • Third party lenses with NX mount
  • Vintage lenses adapted to fit the NX mount
 
This link describes the NX mount and lists all Samsung NX lenses from Samsung and also third party manufacturers: https://en.wikipedia.org/wiki/Samsung_NX-mount

Crop Factor

One thing to remember is that the Samsung NX system has a “crop factor” of 1.5x. If you do not know what this means, google to learn more. Here is a good starting point: http://www.photographymad.com/pages/view/crop-factor-explained
 
In summary, because the sensor of the NX is smaller than full size (24x36mm), the image is cropped (compared to the full size sensor). The end result is that the field of view of a lens when used on an NX camera is more narrow, as if the focal length of the lens is multiplied by 1.5x. The focal length of the lens does not change. This is just a way to compare the field of view of the lens. Since a lot of people are used to focal lengths from full frame 35mm film photography, this helps understand what the sensor sees.

So when you see focal lengths for the NX system, multiply the values by 1.5x to get a value comparable to a full frame camera lens. For example, the standard 20-50mm zoom lens is equivalent to a 35-75mm lens, which is a fairly standard and not very exciting focal length range.
 
 
Zoom Lenses by Samsung
 
These are some zoom lenses that I have tried:
 
  • Standard 20-50mm f3.5-5.6 (kit) zoom lens. A solid zoom lens that has received good reviews. You need to match the zooms, or find some way to link the lenses. The zoom control rig is easy to rotate. StereoPhoto Maker (SPM) will align images with differences in focal length (just a matter of scale difference), but within limits.
 
  • 16-50mm f3.5-5.6: This was standard I believe with the NX500. It is a compact lens (see picture below) and attractive for its wider end (16mm) and also because it offers image stabilization (turned ON through the menu, one of the few lenses with this ability). However, it is a motorized zoom lens and does not show the focal length outside or on the screen of the NX1000 cameras, so there is no easy way to match the focal lengths from each camera, other than the two ends. Another kit zoom lens is the 18-55mm lens that came standard with the NX300 cameras, I believe.
 
 
  •  50-200mm f3.5-5.6: The longest lens by Samsung, useful for wildlife, long distance action, etc. Does not fit the 68mm spaced camera but most likely it will be used with side-by-side cameras. Here is a picture of me with these lenses. I took some nice bird shots and pictures at a baseball game with these lenses.

 
The picture below shows the zoom lenses discussed above.  One last comment is that the 20-50mm is the only lens that locks (manually) and needs to be unlocked to use.
 
 

 
Other zoom lenses that I have not tried include the 15-50mm f2-2.8 (note wider maximum aperture than the standard zoom lens), 18-200mm f3.5-6.3, 50-150mm f2.8 (fast fixed aperture).

Matching Focal Lengths: With the 20-50mm lenses, one has to match the focal lengths, if using anything other than the two ends (20mm, 50mm). This is usually done by matching the focal length markings on each lens. This is a bit of a problem in the z-configuration where the left lens is upside down and you cannot see the markings. I have used a marker to mark the back side of upside down lens. Another option is to use some kind of mechanical method to link the zooms. I know a couple of people are working on this. I will update this section when I see an interesting solution.

Zoom vs. Fixed FL Lenses
 
After using the standard 20-50mm lenses, I decided that I prefer to shoot with fixed focal length lenses, for three reasons:
 
  1. Fixed focal length lenses are more compact.
  2. They are faster (have a large and fixed maximum aperture)
  3. The focal length cannot be changed accidentally. This is easy to do with the 20-50mm lenses.
 For those who find themselves using the wide and of the 20-50mm lens 99% of the time, why not use the 20mm lenses to get a faster (f2.8 vs. 3.5) and more compact/lighter rig, without worrying about accidentally mismatching the focal length?

An interesting side-effect of using fixed focal length lenses: If I happen to have the 45mm lenses, I change my composition and subject framing, to match the lenses. It is a bit of a challenge to use the lenses that I have on the cameras for any situation I find myself into, and the results are often rewarding (unusual composition, different point of view).

One last comment: I survived 30 years of fixed focal length lenses with my Stereo Realist and RBT S1 stereo camera. Yes, I did try zoom lenses with RBT SLR-type cameras, but soon switched to fixed focal length lenses there too. Zoom lenses are a convenience (carry less weigh, be able to change the focal length to compose better) but at the expense of quality, in my opinion.
 
Fixed Focal Length Lenses by Samsung
 
Samsung makes a wide range of compact pancake type fixed focal length lenses:
  • 10mm f3.5 Fisheye: Very tiny!
  • 16mm f2.4, a fine performer
  • 20mm f2.8, has now become my standard lens
  • 30mm f2.0, has received good reviews
  • 45mm f1.8, hands down my favorite lens
 
These lenses (except for the 30mm lens that I do not own, it is similar in appearance to the 20mm lens) are shown in the picture below.
 
 

It is interesting to note that all NX lenses come several colors. The most common are black and white. But there is also pink and silver (the 20mm lens above is silver). The camera bodies also come in different colors (black and white are the most common but I have seen pink too). Some people like to use a different color so they can immediately tell which is the R and which is the L camera/lens. I used to do this too, but not any more. My color of choice for the camera bodies now is white, and black for the lenses.
 
All these lenses above fit in the cameras separated by 68mm. Two more specialized lenses that I own (these are not pancake, they are both large and heavy):
 
  • 60mm f2.8 macro
  • 85mm f1.4, great portrait lens but too large and heavy
 
 

  [The 20-50mm lens is shown for comparison]
 
My first two pairs of lenses were the 20-50mm and 50-200mm. My next pair was the 16mm. I found the 16mm too wide for general use, so now I use the 20mm lenses as my standard wide angle lenses.
 
The Samsung NX 45mm f1.8 Lens

 
The 45mm f1.8 lens gives me excellent results even wide open. I have several examples on my Phereo account. Here are some advantages of the large maximum aperture (f1.8):
 
·           Can throw the background out of focus, which is useful for available light portraits: http://phereo.com/image/59258532e7e5649c4600024b
 
·           Can be cropped without grain or much image quality loss because of the low ISO and sharp image. This picture was taken at a show at night. It has been cropped a lot and still looks sharp. The fast aperture helped me use a fast shutter speed to stop action, at a reasonable ISO:
 
 

 
·           If you shoot through wires with wide open aperture, the wires disappear. This is what happened in this picture: http://phereo.com/image/592585f1e7e5647e63000185  I took this at the local museum of Natural History. I was shooting behind a wire link chain fence, not between the openings (which were too small). There are wires in front of the lenses but using the wide f1.8 aperture, makes them disappear. Also, this picture is cropped quite a bit, I was a lot farther than it appears.
 
2D/3D: An interesting thing about the 45mm lens is that it comes in 2D and 3D versions. The 3D function does not work with the NX1000 cameras (the lens behaves exactly as the 2D version, as a matter of fact my pair consists of a 2D and a 3D lens) but it works with all later models. The lens has an aperture with two openings and the camera takes a sequential pair using a rather small (8mm) stereo base. The settings in 3D are very limited, so this lens as 3D is not of much use for stereo photographers.
 
Non-moving Front: Another unusual feature of the 45mm f1.8 lens is that the front element does not move when the lens focuses. This is useful when you flush the lens on a glass, or when using polarizers or any graduated filters in the front. If the front element moves, focusing is impaired when the front if flushed on glass and the lenses might not be able to focus. No problem with this lens. For other lenses I use a rubber shade to block reflections and avoid touching the glass.

A Tip for Carrying/Storing Lens Pairs

I used to throw all the lenses inside my camera bag. They would bang each other and get nicked. I have dropped lenses as I pulled them out of my bag. Now I am trying to be more careful and better organized. Here is what I have done:



I have glued together two back lens caps, using superglue (an alternative to superglue is to use double-sided foam tape, which allows you to separate the caps later). I use generic caps. Some of them do not hold the lens well, so make sure you find one that does.

I then attach the matched lens pair to the twin cap. I then use an OP/TECH foldover pouch to store the pair. These are soft, durable, neoprene pouches, that protect the lenses.

For the 10, 16, 20, and 30mm lenses, also 16-50mm zoom, the size pouch is 253 (2.5x3 inches)
For the 45mm lenses (also, the 20-50mm zooms), the size needed is 2.5x4 inches.
For longer lenses (50-200mm, for example), I do not bother.They are too long to keep like that.

Another useful accessory is rubber shades. I prefer foldable rubber shades which work better when I flush the lenses to glass (airplane window, for example). Finally, I use generic lens caps (about $1 each) so I do not worry about losing the original lens caps. 

Here are all the parts taken apart:



It helps that ALL pancake Samsung lenses use the same filter size: 43mm.
 
Third Party Lenses with NX Mount
 
Samyang Optics (a Korean company) has made lenses with the NX mount. These also come under different names, such as Bower and Rokinon. Here are some lenses that I have owned and tried:
 
  • 8mm f2.8
  • 12mm f2.0
  • 85mm f1.4
 
These lenses have the correct NX mount but are manual focus only. I tried to get lenses not covered by Samsung. The plan was to use the 8mm or 12mm for night/star photography. They are both faster than the Samsung 10mm f3.5 and focusing is not important.  The 85mm was a lot cheaper than the Samsung one but without AF. Unfortunately, unlike the wider lenses, focus does matter for the 85mm especially for portraits, etc.
 
Here is a picture of some fixed focal length lenses, from left to right:  Lensbaby 5.8mm f3.5 circular fisheye lens,10mm f3.5 Samsung, 8mm f2.8 Rokinon, and 12mm f2.0 Rokinon lens. The Samsung stands out as being the smallest of the bunch.
 
 
 
Vintage Lenses
 
Most vintage lenses by Nikon, Canon, Olympus , Pentax, Minolta, etc., can be used with the NX cameras using the appropriate adapter. These adapters are inexpensive (often as low as $10). They are basically hollow tubes (no lenses) that serve two purposes:
  1. Adapt the mount (Nikon, etc., on the front, Samsung NX on the back).
  2. Take care of the infinity focus.
 
Here is how the MD to NX adapter looks. This picture shows three adapters at different angles. The black end goes to the camera. The Minolta lens attaches to the silver end.
 

 
Infinity focus should be preserved, but you need to check this. I have found some variations, so I always focus by looking at the screen, not the lens focus markings.
 
Because of the 1.5x crop factor wider lenses are not very useful (they are heavy and expensive and Samsung has plenty of those). But Samsung  lacks in long lenses so I am using Minolta lenses (with the appropriate MD to NX lens adapter) to cover these longer focal lengths. Here is what I have:
  • 50mm f3.5 macro
  • 85mm f2.0
  • 100mm f2.5
  • 100mm f4 macro
  • 135mm f2.8 and f3.5
  • 200mm f4
 
All these lenses above fit with the cameras at 68mm separation.
 
I also have these lenses that I have used for bird photography:
  • 300mm f4.5 and f5.6
  • 500mm f8 (mirror)
 
Here is a picture of some lenses from my collection:
 
 

 
The 500mm is a mirror type, so it is compact by design. The 300mm lens has a mounting collar which helps ease the tension from the camera. The 200mm lens is about the length and weight of the 50-200mm Samsung lens, but it this thinner and also faster (f4 vs. f5.6).  The 135mm f3.5 lens is really lightweight and a bargain at about $20 used.

These Minolta lenses need to be focused manually (the aperture is also set manually).  Because they are longer lenses, focusing is rather critical. It would be nice to have a system that links the focusing rings of the lenses. One feature I use a lot for critical focus is to magnify the image by pressing the center button in the back - see also:http://drt3d.blogspot.com/2017/07/tips-for-using-twin-nx1000-cameras.html
 
Here is an example taken with the 500mm mirror lens:
 
 

 
 
In Summary

Even though the NX system is dead, there are plenty of lenses to use. This includes lenses from Samsung, third party lenses with NX mount, and vintage/legacy lenses with an adapter. I have accumulated a large number of lenses. Come to think about it, after investing a lot of money on lenses and accessories (mounts, remotes, etc.) the price of the camera body has become almost irrelevant. The investment is in the lenses and accessories. The camera bodies are disposable.

My own personal shooting style favors fixed focal length lenses. I like the pancake lenses by Samsung because they are compact, lightweight, of good quality, and can auto focus. The 20mm lens (35mm equivalent) is my standard wide angle lens. The 16mm is used for indoor shots or when a wider angle of view is needed. The 45mm f1.8 lens is used any time that I do not need a wide angle.

If, in a previous life, you used a different system (Canon, Nikon, Pentax, Minolta) and still have the lenses, you can use these lenses with the Samsung NX camera and an inexpensive adapter. For example, if you do not want to invest in the (rather expensive) 45mm f1.8 lenses, an alternative is to use normal 45-50mm f1.7 lenses found used for maybe $20 for most camera systems. You will lose auto focus.

As I was organizing my lens collection, my wife asked me: “Why do you need all these lenses? Don’t you miss shots as you switch lenses?” Yes, that’s true, and that’s one reason to use zoom lenses. But different focal lengths allow you to take different pictures. And the wider maximum aperture allows you to use faster shutter speeds and/or lower ISO.

We are really fortunate to we have access a variety of lenses that we can use with cameras with normal stereo base (Samsung NX1000 cameras in the z-configuration) and I am taking full advantage of it.
 
 

Friday, July 14, 2017

Tips for Using the Twin NX1000 Cameras

A friend recently sent me pictures from his NX1000 rig that were hopelessly out of synchronization. I had a few experiences like that of my own too. So, here are my recommendations on how to use the twin NX1000 rig to assure good synchronization:
 
  • Before You Start: Make sure that both cameras have the latest firmware installed (1.15). Also, do the “Flash Test” (see the blog on this) to make sure that the pair shows good synchronization. Mark the cameras R and L so you always use them in the same way. Also, mark the memory cards R and L to make sure the same card goes back to the same camera. Finally, change the default menu options to choices of your liking. These steps are described here: http://drt3d.blogspot.com/2017/07/putting-twin-samsung-nx1000-camera-rig.html
  • How to Turn the cameras ON / OFF: These cameras have a peculiarity: If their remotes are connected then when one camera is off, the other camera will fire. It is as if the camera that is OFF acts as a closed switch for the camera that it ON. So, if you turn one camera ON while the other is OFF, after a short time (maybe 1 second or so) this camera will fire. And if both cameras are ON and you turn one OFF, then the other camera will fire. To avoid this, the cameras can be turned ON or OFF at about the same time (within one second). But if they are turned ON too close to each other, then one camera will not detect the remote. (This was explained by Werner as follows: When the cameras are turned on, they send a pulse to detect the remote and if the pulses are too close to each other, one is missed.)

    To avoid these issues, I have turned on the setting to Clean the Sensors at Startup. This gives a bit of extra time to each camera. So I turn one camera ON then the other. Both cameras detect the remotes and none fires. At turn off, I turn both cameras OFF at the same time. Using this simple procedure I get no misfires and no remote problems.
[PS. Others have found other ways around this. One user keeps the lens caps on. This stops the cameras from focusing and if they cannot focus, they do not fire.]
 


  • Modes to Use: Use these camera modes: P, A, S, M (same mode on both cameras).

Do not use the SMART mode (this delays the camera in an unpredictable way – that was the problem with my friend’s pictures). If using a flash, use a flash that does not communicate with the camera. So, do not use a Samsung dedicated flash (this delays the camera that fires the flash).
 
  • Focusing and Firing: When taking a picture, half-press the shutter button and wait to hear/see the focus confirmation from both cameras (hear the sound and see the green focus confirmation square on the screen), then fully press to take the picture. If one camera has not focused, it will not fire (this is the standard setting) and this will lead to mis-synchronization. Most mis-syncronization issues happen if you hurry to take a picture without waiting for the cameras to focus first. If you want to speed up shooting and the distance to the subject does not change, then switch to Manual focus.
 
  • Focus Setting: Make sure that the focus is set at Single Focusing [SAF] (or Manual focus [MF] if you really want to use this setting), and not at Continuous Focusing [CAF]. It is easy to press the center dial and change the focus mode while trying to get out of the menu. At [CAF] the camera keeps looking for focus and it is delayed.

  • Drive Setting: Make sure that the cameras are set to Single Drive and not timer or any other mode. Again, this setting is easy to press and then change trying to get out of the menu. You can use both cameras in other than Single Drive mode, just not only one.
 
In summary: If you have a pair that has passed the Flash Test, use the P, A, S, M settings, take your time to half press the shutter to focus, and nothing has changed in the focus and drive settings, then everything should be OK. 

In case of trouble: If you notice a problem, lack of synchronization, or any unusual camera behavior, do not panic (“OMG, my cameras are broken!” – this was my reaction when I accidentally changed the focus to CAF and the cameras were clearly firing out of synchronization).  Calm down and examine the settings, make sure that you are using the same mode and shooting variables (f-stop, shutter speed, exposure compensation) on both cameras, make sure that the focus and drive settings are the same. Check that you have not accidentally bumped the zoom or switched to Manual Focus. Turn the cameras OFF and ON. If everything is set properly, the cameras should return to normal.
 

The Center Dial

 
This picture shows how to use the center dial. The dial can be pressed in 5 different ways: Center, up, down, right, left, and it also rotates, plus there are 4 buttons at the corners around it. These buttons and controls have different functions depending on whether you are in shooting or in playback mode.


 
Top Buttons:
 
  • MENU: In shooting: Brings up the menu that allows you to change shooting variables like ISO, White Balance, etc., and also menu items. After the initial changes, I normally go there to change the ISO or white balance. But these can also be changed with the Fn button. In playback mode you get a different menu.

  • Fn: This bring a menu with all the shooting variables so you can change all variables in one convenient place. That’s a useful shortcut. In playback mode it has options for manipulating the image you have recorded.
 
Center Dial:
 
  • Top: DISP: Changes the display. Experiment with this to set the display to your liking. Since you are using two cameras, you can have two different displays, for example, turn the electronic level ON in one of the cameras but not the other. In preview mode you can pull up information about the recorded image.

  • Bottom: Exposure Compensation: Allows you to change the exposure compensation (when appropriate). The same can be achieved using the Fn button, which is a bit easier to see, in my opinion.

  • Right: Changes the focus mode. Remember, you want [SAF] (or [MF])

  • Left: Changes the Drive Mode. Normally you are using Single Drive, the most left setting.

  • Center in Shooting Mode: Pressing the center dial in shooting mode allows you to change the size and location of the focus area. I change this setting when I take close-ups, where I converge the focus area towards the center. This remains in effect even after the cameras are turned off, so if you change it for close-ups and then switch to shooting with infinity, you might want to bring the focus areas back to center. 

  • Center in Playback Mode: In playback mode pressing the center dial enlarges the image to see details. Rotating the dial changes the magnification and you can also move around to see different parts of the image. This is a useful operation that allows you to closely inspect your images to make sure that they look OK.

Bottom Buttons:

  • Playback: Brings up the last image you recorded and you can scroll through by pressing the right or left side of the dial. While in playback mode, the wheel and buttons have different functions than the normal shooting mode.
  •  Delete: Deletes images recorded. If I see that one camera misfired (i.e. only one camera took a picture for one reason or another) then I delete this image at the spot, rather than having to worry about it later. This saves time on image processing at home.
 
If you have any tips about using the cameras, let me know.