N scale photography w/ Nikkor 105mm micro lens

[Ed Kapuscinski]

I wrote this up a while ago. It's imperfect, but I think it covers many of the basics.
http://conrail1285.com/news.asp?storyid=28

People may claim that Helicon is the bees knees. But bees don't have knees, and I don't think it's necessary.

[wm3798]

I shot this with my Canon S-2 at close range with the macro setting on.  I set the ISO down to 80 (lowest available) and ratcheted up the exposure to 8 seconds or so.

The DOF is not what you can achieve artificially with Helicon, but it's much better than I expected.  I suspect that if I dropped the lighting down a bit further and extended the exposure time a bit, I could improve it further.

Lee

[wcfn100]

People may claim that Helicon is the bees knees. But bees don't have knees, and I don't think it's necessary.

Helicon certainly isn't necessary.  But you cannot achieves results that are even close without it.  I need to do one Helicon set-up with this lens to see how much halo I get.  I'm thinking that the software will be even more useful with a true macro lens than the pseudo macro settings that P&S zoom lens cameras gives.

Jason

[wcfn100]

OK, so here it is. 



Compiled from about 10 shots.  I think I could do a couple more shots and adjust the lighting to lose the washout on the Rath car.  Again, it's the perspective that throws off the shot due to the long focal length which is again somewhat offset by the fact that I can take the photo 8-9" off the front of the benchwork.  Obviously for shots like this you don't need a micro lens, but I just wanted to see the results.  I going to take the same sequence with the regular 18-55mm lens to see what the difference is.  I wish a had a 24mm lens like David talks about.


Jason

[wcfn100]

So to compare..  First I had to shove everything about a foot closer to the camera then shot the same scene at 35mm and 55mm with everything else the same.  The differences speek for themselves.





Jason

[tom mann]

Why is Helicon needed?

With a 60mm macro lens at F22, I can photograph a Z scale boxcar at a 3/4 view and pretty much get the whole car sorta-kinda-in focus, good enough for a resized 1024x768 web image.  However, if I open up to F8, a portion of the car is very sharp, but it requires 8 different photos each focused on a different portion of the car that Helicon can assemble.  But the resulting photos can be used without resizing.

Now, at HO scale, the lens moves backwards and the whole car is in focus by F11. 

So Gary's shot would benefit first from a smaller aperture, which comes at the expense of crispness.  If he wanted a sharp-as-can-be photo, he would need Helicon.

[Chris333]

In the first shot the reefer may be washed out because there is no weathering, everything is shiny. I bet if you put those cars to the rear it would work better.

[wcfn100]

Gary, what knid of camera do you have?


Like Tom said, the easiest (my word) way to get DOF is a smaller apature setting.  You can do a lot with just that.  I would look at what Ed and Lee have posted to see the great results.  But you can also see what Tom says about cripsness.  Compare the LV boxcar in Lee's shot to the end of the Rath car in my shot.  Lee's is in focus enough for just about any type of application, but it's not as 'crisp' as it could be.  Also, in the shots that I took using Helicon, you can see that the end of the last car is just as crisp as the end closest to the camera.  Now that isn't really like real life either but it's sort of the point when using Helicon focus software.

In the first shot the reefer may be washed out because there is no weathering, everything is shiny. I bet if you put those cars to the rear it would work better.

Yeah that yellow is pretty bad but I also have the lights about 8" away which really floods it on a timed exposure.

It is patially the

[Ed Kapuscinski]

Tom, I think it's important to keep in mind that shooting a single boxcar is far different from a whole scene.

[wcfn100]

I occurred to me that to really appreciate Helicon you need to see the image at full size.  Keep in mind I didn't do all the shots I could have so there are a couple places where you can see it go in and out of focus.

http://members.cox.net/jasonkliewer3/post/55mm%20helicon%20compare%201.jpg

If anyone wants to see the individual shots, I can post the sequence.


Jason

[tom mann]

Tom, I think it's important to keep in mind that shooting a single boxcar is far different from a whole scene.

When objects get close to the camera, Helicon comes in handy.  You're thinking of a whole scene that is in the same plane to the camera.  So there are scenes that don't need Helicon, and scenes that need it (compare yours to Jason's).

[GaryHinshaw]

My shot was taken with my son's old Nikon Coolpix point & shoot, which I know is inadequate for this application.  One of the reasons for my question is to help me decide what I need most in a new camera.  Clearly aperture priority and manual focus (I believe these are independent features) are key.  I'm not too interested in dropping $500+ on an SLR, so it is good to hear about options like Ed's A520 (nice article BTW).  I'd be real happy with the kind of results Lee is getting too.  Jason, could you clarify which of the images you posted on this page used Helicon?  The depth on all of them is great.

But I'm still trying to get a better handle on the physics of depth of field vs. field of view.  Are these quantities simply inversely proportional for a fixed aperture size?  (Perhaps there a better way to pose this question.)

Thanks again.

Edit - just saw Tom's post.  That's what I want to understand better.  BTW Tom - you're going to have change your signature photo soon.  My wife is getting suspicious and it's very distracting. 

[Walkercolt]

All things being equal(F-stop, reproduction ratio ie: size on the film compared to life size) a wider angle lens produces more depth of field(which really should be termed depth of focus). In miniature photography, a wide angle lens provides the persective we expect to see in a prototype photograph. This is different than close-up phtotgraphy of small objects or flowers or insects. This is usally termed "macro-photography" and is the range from 1/10th life size to about life-sized on the film/sensor. In macro-photography, a longer than normal focal length lens allows more room for lighting the object, lets you be farther away so as not to distrub the subject and renders the subject in a "rectilinear" fashion, less persective, and less close-up distortion. Like the pictures of small flowers in a guide book, a more graphic representation, much like a scientific drawing. We usually want the opposite in miniature photgraphy. We like the strong perspectives provided by wider than normal lenses, and used judisically, Helicon can be a major improvement. When lenses are stopped down to their minimum apatures for greater depth of focus, you run into an optical effect known as "diffussion" which means the image isn't as sharp as it would be at a larger f-stop. Most lenses are designed to give their best, sharpest images at three or four stops down from wide-open. If the hole the light goes thru is much smaller than that, it is spread-out by the edges of the apature blades. The closer you are to the subject(the larger the reproduction ratio) the more pronounced the effect is. A regular lens is designed to give the best images at "infinity". A Macro(Micro-Nikkor) is designed to give the best images at 1/10th life-size to life-size(1:1). To achieve better results at close range, macro lenses generally have more elements(pieces of glass lenses inside them) and are designed differently, and that costs more. Even Macro lenses are sharpest at f8-f11, then you run into diffusion. I know this is a lot of information to digest, and I've condensed it radically from the textbooks. Kodak sells a Professional Publication, "Close-up and Macro Photography" that deleves into the theory much more, and explains the optical differences in Macro lenses in far more detail, and expounds on lighting close-up work, and tells about a system that works like Helicon, only using a slit-lamp and a moving camera to provide "universal" depth of focus. So for model photography, of a diorama or of a layout, a wider than normal lens at f8 or so and Helicon used with some care, usually provides an image that looks more like the real thing to most people. Individual cars shot "straight-on", your longer than normal Macro lens at f8-f11 will give the sharpest results. Then when you've learned how to do the proper lighting and are getting the same "dead-on" results, going by the rules, then you can learn to bend or break the rules. Books to consult are "Linhof Technica Techniques", "Leica Techniques", "The Hasselblad Handbook", the Kodak publication, and "Macro and Close-up Photography" by Petersens Press and of course "The Camera" by Ansel Adams. These are all probably out of print, except the Kodak book, but they can be found at good camera stores.

[wcfn100]

Jason, could you clarify which of the images you posted on this page used Helicon?

All of the posts so far today with the 5 cars are using Helicon focus.  For another comparison I grabbed the best single image of the 35mm setting to see the difference.  Keep in mind I didn't focus with the intent of just taking one picture.




So with a good apature setting you can get enough focus for most images without needed any post software.  You can see some fuzz in the front left and then of course as you get further back in the photo but in general you'll be happy.  The biggest loss in this photo is the bluffs which show almost no detail.


Jason

[GaryHinshaw]

Jason - impressive depth of focus on that last image w/o helicon.

Walkercolt - Thanks for the info about field of view and perspective.  Food for thought. I agree that depth of focus is the more correct term.  However, the spreading effect produced when waves pass through a finite aperture is called diffraction, not diffusion.  (I reluctantly confess to being a physicist, so while I never studied applied optics in detail, I do know a fair amount about wave phenomena).

Here is a very nice site I just came across with a number of different tutorials that are very well illustrated, including one on depth of field (their term) and one on diffraction-limited imaging:

http://www.cambridgeincolour.com/tutorials/depth-of-field.htm

Cheers.

Edit - ok upon further reading, I see that depth of field and depth of focus are two different things.  The former is the distance over which the subject appears to be in focus (what everyone has been talking about here), the latter is the distance over which the image of the subject appears to be in focus.  This determines how accurately the sensor (or film) must be mounted behind the lens.