I made a 4" digital back, and you can too

[TomR]

The idea is pretty simple; take a digital sensor and move it in a grid where the film would be. I've just got the bits together and it works, but needs refinement.

I took a 4x5 monorail camera, removed the rear standard, back and bellows. In there place I mounted a '4 way macro rail' with a DSLR on it. The key here is the rail is meant to go horizontal, but I added a couple of 90 degree brackets so it could mount vertical. Now I just have to turn the knobs a bit between each photo to move the camera in a grid to cover the film plane.

I'm not great with words so have some photos.

Here is the camera as it stands right now. It needs some work:

http://farm9.staticflickr.com/8117/8697572726_39b328cf46.jpg (http://www.flickr.com/photos/tom_rintjema/8697572726/)
2013-676 (http://www.flickr.com/photos/tom_rintjema/8697572726/) by Tom Rintjema (http://www.flickr.com/people/tom_rintjema/), on Flickr

My first test was with a magnifying glass as a lens:
http://farm9.staticflickr.com/8399/8687700108_1468bbaf3a.jpg (http://www.flickr.com/photos/tom_rintjema/8687700108/)
2013-673 (http://www.flickr.com/photos/tom_rintjema/8687700108/) by Tom Rintjema (http://www.flickr.com/people/tom_rintjema/), on Flickr

Here is with a real lens:
http://farm9.staticflickr.com/8534/8696333293_633652aaa2.jpg (http://www.flickr.com/photos/tom_rintjema/8696333293/)
2013-674 (http://www.flickr.com/photos/tom_rintjema/8696333293/) by Tom Rintjema (http://www.flickr.com/people/tom_rintjema/), on Flickr

http://farm9.staticflickr.com/8260/8696477157_2ed36d68f9.jpg (http://www.flickr.com/photos/tom_rintjema/8696477157/)
2013-675 (http://www.flickr.com/photos/tom_rintjema/8696477157/) by Tom Rintjema (http://www.flickr.com/people/tom_rintjema/), on Flickr

Please excuse the poor photos. I literally got the thing together and went outside to take photos before it got dark.

Some key points:
I used a cheap 4 way macro rail from Amazon. I think it was $40. It's not very good and a better one would help a lot.
A DSLR has a mirror box that's too deep and causes mechanical vignetting. A mirrorless camera would be better, as there is no mirror box and also it would be much lighter.

That's about it for now.

[TomR]

This photo shows how it works best:

http://farm9.staticflickr.com/8121/8696454053_b7eef40936.jpg (http://www.flickr.com/photos/tom_rintjema/8696454053/)
2013-678 (http://www.flickr.com/photos/tom_rintjema/8696454053/) by Tom Rintjema (http://www.flickr.com/people/tom_rintjema/), on Flickr

The front standard is normal. I had to use a shirt as a bellows as the one that came with the camera didn't work for what I was doing. All of the movements work still. The rear standard has been replaced by a set of rails to move the camera that is acting like a back around in a plane. It has no movements, but I plan to add them back in when I make a sturdier system. Right now I'm looking for a set of focus rails that have less slack when held on their side.

[Nathan Potter]

OK, this is frequently tried by others with some degree of success. My own opinion is that it is somewhat pointless in that you end up without some of the key advantages of LF or the DSLR when used separately.

In your last photo of the setup I can't figure out what the gizmo is behind the DSLR.

Nate Potter, Austin TX.

[welly]

OK, this is frequently tried by others with some degree of success. My own opinion is that it is somewhat pointless in that you end up without some of the key advantages of LF or the DSLR when used separately.

In your last photo of the setup I can't figure out what the gizmo is behind the DSLR.

Nate Potter, Austin TX.

That looks like the four way macro rail to me.

94364

[Light Guru]

Why not just use one of these DSLR to 4x5 adapters.
http://www.amazon.com/Fotodiox-10-LA-4x5-EOS-P2-Adapter-Calumet-Horseman/dp/B004G17LFG/ref=sr_1_4?ie=UTF8&qid=1367376414&sr=8-4&keywords=Fotodiox+4x5

Not only can you cane the one image like yours is limited to but you can slide the camera on the adapter and take multiple images and then stitch them together.

[welly]

Why not just use one of these DSLR to 4x5 adapters.
http://www.amazon.com/Fotodiox-10-LA-4x5-EOS-P2-Adapter-Calumet-Horseman/dp/B004G17LFG/ref=sr_1_4?ie=UTF8&qid=1367376414&sr=8-4&keywords=Fotodiox+4x5

Not only can you cane the one image like yours is limited to but you can slide the camera on the adapter and take multiple images and then stitch them together.

I'm curious as to whether anyone uses these adapters with any positive results. I see a lot of links to these things but have yet to read a review.

[SergeiR]

Why not just use one of these DSLR to 4x5 adapters.
http://www.amazon.com/Fotodiox-10-LA-4x5-EOS-P2-Adapter-Calumet-Horseman/dp/B004G17LFG/ref=sr_1_4?ie=UTF8&qid=1367376414&sr=8-4&keywords=Fotodiox+4x5

Not only can you cane the one image like yours is limited to but you can slide the camera on the adapter and take multiple images and then stitch them together.

b/c they suck. You not getting full width with those fotodiox ones.. And they do not make them to full specs. At least not one with mamiya..
After some hacking i could get 6x9 images out of it.. but thats about it. And its a bit.. weird. You getting somewhat stereoscopic effects b/c you move receiver, so your nodal points and stuff are shifting..

http://farm6.staticflickr.com/5303/5677678623_3a668689a7_b.jpg (http://www.flickr.com/photos/sergeistudio/5677678623/)
Cheater (http://www.flickr.com/photos/sergeistudio/5677678623/) by Sergei Rodionov (http://www.flickr.com/people/sergeistudio/), on Flickr


K-Group got more cool ones, but they are WAY more expensive.

[photonsoup]

I took a cambo lensboard and epoxied the mount from an old Nikon lens to it. On the Cambo, the lensboard mounts on the rear standard the same as the back does. I could rise, fall, and shift to cover the entire 4x5 area and stitch them together, but I don't want to spend that much time on the computer!
I have used it for some macro experiments.

Tulip bud about to open
94365
Cambo Legend, Schnieder Symmar 150mm, Nikon D300

But mainly I use it to compare shutter speeds by checking the histograms of a gray wall.
Oh, I did use it to take picts of the solar eclipse cause I could stop down to f64

[Light Guru]

b/c they suck. You not getting full width with those fotodiox ones.. And they do not make them to full specs. At least not one with mamiya..

I didn't say they were a perfect option. But it is far better then the hack in the original post.

[TomR]

I must not have explained what I'm doing here properly. The gizmo behind the DSLR is indeed a 4 way macro rail, as my post states. It has 10cm of travel both left and right and up and down. What I do is move the camera left and right and up and down taking photos in a grid pattern to cover about 4" x 4" (10cm x 10cm) and stitch the photos together on the computer. Photoshop even has an automated feature that does this with little user input. The result is a photo over 100 megapixels that covers almost what a 4" x 5" negative would.

Just to be clear, each of my sample photos isn't one picture taken with a DSLR mounted in a static position cropped out of the middle of a LF lens field of view, it's a series of photos stitched together that covers most of the view 4x5 would. That's the reason why I don't use the fotodiox adapter, they just let you slide the camera back and forth and use a small area.

[Jim collum]

with an actual 4x5 camera & back, you'd have rise & fall ... which would accomplish the same thing with the sliding adapter.


I must not have explained what I'm doing here properly. The gizmo behind the DSLR is indeed a 4 way macro rail, as my post states. It has 10cm of travel both left and right and up and down. What I do is move the camera left and right and up and down taking photos in a grid pattern to cover about 4" x 4" (10cm x 10cm) and stitch the photos together on the computer. Photoshop even has an automated feature that does this with little user input. The result is a photo over 100 megapixels that covers almost what a 4" x 5" negative would.

Just to be clear, each of my sample photos isn't one picture taken with a DSLR mounted in a static position cropped out of the middle of a LF lens field of view, it's a series of photos stitched together that covers most of the view 4x5 would. That's the reason why I don't use the fotodiox adapter, they just let you slide the camera back and forth and use a small area.

[TomR]

My actual 4x5 camera that I have right here, which I took the rear standard off of to do this experiment, does not have 4" worth of rise and fall on the back. I wanted a solution that kept the rise and fall of the front standard for adjusting the image. Also the focus rails have quick adjustments. 1/2 turn of the knob moves the camera 15mm, so it's fairly fast to move the camera enough to cover the image.

[barnninny]

I think it's an interesting idea. I'll be following along to see how it progresses as you tweak it.

[TomR]

Thank you. Right now the biggest problem is the DSLR being too heavy for the cheap rail. It sags a little and I want to be sure the sensor stays aligned to the film plane, so I'm going to have to do something about that.

[barnninny]

Get a 2nd-hand, inexpensive mirrorless to experiment with?

[coisasdavida]

Your solution solves a major problem of the back adapters for DSLRs, the length they have in order to clear the hand grip of the camera. When using those adapter you end up using very long lenses.

A mirrorless camera, inside a recesser lensboard custom adapter in a Sinar P camera could be great.

[Amedeus]

TomR does have an interesting low cost approach although there are some mechanical hurdles to clear.

I've been using Phase One Flexadapter for Leaf MF back on my Sinar and also an inexpensive Chinese sliding camera mount for 4x5 for my Mamiya 645 to achieve same. Both have their pros and cons from cost and flexibility perspective as one doesn't get the full 4x5 coverage unless you use res and fall which is not an issue on most 4x5 cameras. OTOH, 6x9 results for me in 30"x45" prints easily and depending on subject and the work involved, all the way up to 48"x72" ... plenty for now.

Yes, sliding your camera across the back does add distance to the lens so there's a limitation on focal length of lenses you can use. Penalty is anywhere form 44mm to 89mm depending on the camera you use ... no-mirror camera should be in the 12-25mm range ... hence the reason some use Flex Adaptors or other sliding back arrangements, the latter are typically no different than using a film holder with it comes to impact on lens focal length.

Sergei ... I didn't get the comment on the nodal point shifting ... when properly done you're just scanning the film plane of the camera with the sensor, so nodal point wouldn't change as the lens is not changing or do I miss something ? LCC correction may be required though ...

[TomR]

I changed how I had the horizontal slide mounted. This places the stresses on it the way it was meant to take them, allowing it to work much better. My next step is to make a bag bellows that I can velcro around the DSLR. After that I guess I'll have to get a mirrorless camera if I want to use any wide lenses, as the mirrorbox on my DSLR is causing vignetting.

I did have to take of the rear standard and back from my camera to allow my DSLR to get close enough to the lens to focus properly. I'm guessing if you have a camera with a much wider range of movements than I have then you could have just taken the back out of the rear standard and stuck a digital camera in there. That would have been a lot less work, but I'm pretty happy with my results.

I don't think you have to worry about nodal points shifting, the lens stays fixed.

http://farm9.staticflickr.com/8255/8701131661_063f64bbe2.jpg (http://www.flickr.com/photos/tom_rintjema/8701131661/)
2013-679 (http://www.flickr.com/photos/tom_rintjema/8701131661/) by Tom Rintjema (http://www.flickr.com/people/tom_rintjema/), on Flickr

[Peter De Smidt]

What's the advantage over using a dslr with a standard panoramic head?

[Ben Syverson]

What's the advantage over using a dslr with a standard panoramic head?
Since this is mimicking a virtual LF sensor, the advantages are LF's advantages; movements, great lenses, shallow depth of field, etc. You also wind up with a rectilinear image, whereas when you stitch images using a small format camera, you tend to end up with cylindrical or spherical projection images, which have a much different look.

[Kirk Gittings]

Since this is mimicking a virtual LF sensor, the advantages are LF's advantages; movements, great lenses, shallow depth of field, etc. You also wind up with a rectilinear image, whereas when you stitch images using a small format camera, you tend to end up with cylindrical or spherical projection images, which have a much different look.

I've done both and this is not a real difference with modern stitch software.

[TomR]

Another quick one from my front lawn.
http://farm9.staticflickr.com/8124/8702406108_cdb752f0b8.jpg (http://www.flickr.com/photos/tom_rintjema/8702406108/)
2013-680 (http://www.flickr.com/photos/tom_rintjema/8702406108/) by Tom Rintjema (http://www.flickr.com/people/tom_rintjema/), on Flickr
This image is over 15,000 pixels wide.

The main advantage of using a fixed lens and moving the sensor, over a panoramic head is you only get the lens distortion and vignetting once. If you take a series of photos with a 35mm format lens and stitch them together you have to correct for the lens distortions and vignetting for as many exposures as you take, which doesn't work out perfectly all the time. Also you don't get any of the parallax problems you may run into with a panoramic head.

[Jim collum]

I did a writeup on a tool back in 2004.. you can probably still find them in the used market... that pretty much did this.

http://www.outbackphoto.com/workflow/wf_48/essay.html

The original site of the tool is at http://www.patrikraski.com/#/studiotoolstm .. pretty sure he's not making them any more, but you can probably email and see

[TomR]

Thanks Jim. I've read that essay before. I see you ran into some of the same problems I am. I think it's important to note that I have been trying to do this on as tight a budget as possible. I've spent about $40 in parts so far. The monorail I bought used for $100 or so. I just like to tinker with things.

Don't worry though, I didn't destroy any of the components of the camera and I have ordered some film to use in it.

[Vaughn]

Actually, I was hoping to see an article about ripping the sensors out of cameras and making one's own large sensor for 4x5... ;o)

[Jim collum]

if i were a hardware guy, instead of software.. i'd of probably tried it by now :D

[Brian Ellis]

You certainly have my admiration, I wouldn't even attempt something like this because I'm sure I'd end up with a bunch of parts from a ruined LF camera and a ruined DSLR scattered around on the basement floor. And some of the pictures look great. I haven't studied what you did because I'd never be able to do it. But from skimming quickly, and assuming that I use a DSLR with a 3"x3" viewing screen and a TS lens, is it correct to say that what you gained here is an extra inch on each side of the screen (4"x4") and maybe a little more in the way of movements?

[Farside]

That's a VERY interesting thing to do.
Now I'm eyeing up a View II and a Canon 10D, both doing nothing.
Actually, since there's no permanent mods to either, the K20D would be better for end detail.

[erie patsellis]

Or, debayer a sensor ( see http://stargazerslounge.com/topic/166334-debayering-a-dslrs-bayer-matrix/ ), make a similar mount and have a true b&w camera.

Even though it can be painfully slow at times, I prefer using my Dicomed scan back on either the Sinar or RB.

[paulr]

If you could biu OEM sensors from Sony and get a circuit board made, you could do something almost practical with a pair of sensors. If they're oriented vertically, and spaced just fractionally under an inch apart side by side, you could mimic a 3x4" sensor with just 4 exposures. If you're using 24 megapixel sensors, you'd have nominally 192 megapixels. The pixel pitch would be over 5 microns, so it wouldn't be excessive for the best LF lenses under the best circumstances. Even just using 12 megapixel sensors would have a lot of potential.

I have no idea how hard it is to get these parts, or how unreasonably hard the electronic engineering and assembly would be. Probably more like side project for a rich tech company than DIY.

[Simon Liddiard]

It has 10cm of travel both left and right and up and down. What I do is move the camera left and right and up and down taking photos in a grid pattern to cover about 4" x 4" (10cm x 10cm) and stitch the photos together on the computer. Photoshop even has an automated feature that does this with little user input. The result is a photo over 100 megapixels that covers almost what a 4" x 5" negative would.


When I tried this with my Nikon D700 I was getting vignetting from the mirror box after only a few cm of travel. How are you getting 10cm, or were you overlapping sufficiently that the vignetting is removed in the stitching?

[TomR]

I started with a full frame camera and moved to a crop sensor. The smaller sensor let me move farther before it would pick up the vignetting from the mirror box, but I still had to overlap a lot to get the full 10cm. Most of the time it wasn't worth it so I just stopped before 10cm. A mirrorless camera with a short flange distance would help a lot and I think solve most of the problems. Something like a Sony NEX would be perfect I think.

[Simon Liddiard]

Ah of course. That makes sense. Cheers Tom