Macro lens: do I need rails and/or image-combining software to get good results?

[brucehughw]

Hi, all.

I just purchased a used 105 mm Nikkor F2.8 "micro" (as they call it) lens. This allows 1x magnification on a full frame camera and 1.5x magnification on my Nikon D7000. I spent some time in a greenhouse yesterday, looking for cacti and tropicals before I got back out in the real weather.

The focus distance, as I found out, is incredibly sensitive to changes in lens focus (turning the lens manually). I wasn't thrilled with the results I achieved, but it was only my first try with the lens.

I've seen focusing rails online, anything from $85 Manfrotto to $350 Really-right-stuff (I think). For macro work, plants, insects, nothing scientific, do I need one of those rails? I don't plan on taking multiple images and combining them, although I may need to if that's the only way to get decent macro results. Anyway, if experienced photographers can comment on the rails and need for multiple images, I'd appreciate it.

Thanks, Bruce

[PhotomanJohn]

Hi, all.

I just purchased a used 105 mm Nikkor F2.8 "micro" (as they call it) lens. This allows 1x magnification on a full frame camera and 1.5x magnification on my Nikon D7000.

Bruce - The magnification refers to the size of the subject versus the size of the image on the sensor so it is independent of sensor size. The difference on your D7000 versus full frame is that you will get less coverage of your subject at 1:1.

To answer your real question, rails are very handy things for macro work but not absolutely necessary. It is really a personal thing. Lots of folks do excellent macro work and don't have a rail. If you plan to work mostly at full magnification, then it will probably be worthwhile. I have the RRS one which works well.

John

[brucehughw]

John,

Thanks very much. Do you use focus-stacking software?

Bruce

[Venser]

No, you don't need rails.
A good example is the work of Thomas Shahan. It's all handheld.

In terms of focal stacking I use Photoshop. I've been satisfied with the results.

[brucehughw]

Thanks, Chris! Always nice to avoid an unnecessary purchase.

[rpcrowe]

IMO, focus stacking is fine for many instances but, is not generally necessary for the majority of macro work. In fact, there have been zillions upon zillions of great macro images taken without the focus stacking technique.

The use of a focusing rail This one is mine...

...combined with a decent tripod and tripod head can make life a lot easier when shooting macro photography, especially when approaching 1:1 ratios. I will often focus by moving the entire camera back and forth. This rail is exceptionally solid (I think the triple rails setup can take credit for that) but, can only be adjusted back and forth. Some rails allow a bit of side to side adjustment. However this will often lessen the solidity of the rail, especially in less expensive (Chinese manufactured) rails. The quality of a rail is quite important. A wobbly rail that cannot make minute finite adjustments that hold fast is worse than no rail at all. I purchased this older Minolta rail, used from eBay, for about fifty U.S. dollars, years ago.

BTW: when we talk in image ratio, we are talking about the relationship between the subject and the image on the sensor. Since it is very very seldom that we view an image at the sensor size, all images shot at a 1:1 ratio are actually seen at greater rations when enlarged to print or monitor size...

John is totally correct when he mentioned that the image ratio is independent of sensor size. If you need an image ratio greater than 1:1 with your present lens, there are a few ways to achieve this:

1. Use a close-up filter on the lens which will allow you to focus closer to the subject and therefore get a larger ratio - you may probably see a slight deterioration in image quality. The amount of deterioration would be dependent on the quality of your close-up filter.

2. Add an extension tube between the lens and camera which will also allow you to focus closer achieving a greater ratio - the quality of the extension tube will not impact your image quality. However, many "el-cheapo" extension tubes do not have electrical contacts between the camera and lens so you cannot adjust the f/stop.

3. If the lens and camera permits (see *** below), using a teleconverter between camera and lens. This will increase the focal length of your lens but MFD will remain the same which equals a greater image ratio.

NOTE*** I cannot use my 1.4x Canon TC with my 90mm f.2.8 Tamron macro lens because the combination will physically not fit - due to the depth of the elements. I could use the TC if I place an adapter ring between the lens and the TC to give room for the elements. I have not done this. I don't know if this is true with other lens/TC combinations but it would be worthwhile researching before you try to fit a TC onto a macro lens...

[chauncey]

Bruce...no, you don't need rails, but it does make it a lot easier.
Failing that, another alternative is auto-adjusting software that moves the focus point automatically.
http://www.bing.com/search?q=Focus+S...ews&FORM=R5FD2

Sensitive you say...take a gander here http://www.dofmaster.com/dofjs.html
and you will see what sensitive means. At macro distances I don't go over f/11...narrow DOF.

There are those that can handhold, they are rare and your keeper rate goes south quickly.

[FrankMi]

Hi Bruce, there are two primary ways to change the focus on a camera, adjust the focusing ring and move the camera. The benefit of the focusing rail is that you can move the camera, and thereby change the focus, by an extremely small and measured amount. Usually, you can't be near so precise with the focusing ring (unless the ring is moved by tethered software but that's another story). I use the Velbon Super Mag Slider rail when necessary but because I rarely do macros of extremely small subjects, it is rare that I need the rail.

So when would you use the focus rail? Usually in macro work for focus stacking images. It is not needed for single image shots.

For Focus Stacking of a Short Stack - around 15 or less images, then Photoshop works quite well. For larger stacks, I would use a dedicated application such as Helicon Focus or Zerene Stacker. Cleaning up artifacts in the larger size stacks can get fairly tedious in Photoshop.

[chauncey]

For Focus Stacking of a Short Stack

Au contraire mon ami...using PS CC, I routinely use 40-70 stacks...but probably unnecessarily.

[FrankMi]

Au contraire mon ami...using PS CC, I routinely use 40-70 stacks...but probably unnecessarily.

Perhaps the difference is that I manually resolve the artifacts image by image at a pixel-peeping level that CS5 leaves behind and every stack I've created in CS5 has what I consider to be noticeable artifacts.

Also, CC may very well do a better job than CS5. Perhaps I am simply too fussy but I enjoy doing post processing and don't mind the time it takes to make the corrections.

[Venser]

A very good video by Thomas Shahan.
Watching his youtube channel makes you smarter.

[brucehughw]

Richard,

Thanks a lot for sharing everything and for helping me make some informed decisions. A focusing rail sounds like a good idea because I do plan on approaching 1:1 image ratios. I took a quick look at ebay. Quite the distribution of prices. Lots of inexpensive and probably cheaply made rails, some in the $90 range, and some $300. I'll watch for a used one in the mid range.

Thanks again, Bruce

[rpcrowe]

Wow! When I purchased my Minolta unit, there was a plethora of Minolta Focusing Rails available on eBay with about fifty U.S. Dollars the standard price. I only saw one on eBay today and that one was from Germany at a $180 price. The two others were bellows units.
Unfortunately, I cannot advise you on any other unit except the Minolta because that is the only one thet I have ever used. Mine is built like a tank. It was discontinued years ago but is still held in high regards by macro shooters.

[DanK]

Bruce,

You have been given a lot of good information. I will add my 2 cents.

No, you do not need a focusing rail for macro work at 1:1 magnification. Take a look at my site, which has lots and lots of macro shots, many at magnification somewhat above 1:1. None of them were taken with a rail. I don't own one and have never used one. I would definitely consider it for my higher levels of magnification, where the precision of adjustments between shots is more exacting. At this level, however, simply changing focus manually works just fine. You may find that you prefer to use a rail, and if so, that's the way to go, but you don't need it.

Re stacking: If you have photoshop, you might want to start with it, simply so that you can use familiar software and not buy new software. If you get hooked on stacking, as I have, then specialized software would be worthwhile. I personally use Zerene, which is fast, offers two different stacking algorithms that sometimes work quite differently, and offers very good retouching capabilities for artifacts when they happen.

If you are going to be doing flowers indoors, then two things you will want are a good tripod and lighting. I use continuous lighting, but many people use diffused flash.

I see you are in Boston. The Boston Camera Club (of which I am a member) occasionally has educational sessions on various aspects of macro. Both I and one other member have taught sessions on stacking. I don't know this year's educational schedule, but you could check out the website.

Dan

[PhotomanJohn]

John,

Do you use focus-stacking software?

Yes I do and find it a lot of fun. I have PS CC, Zerene and Helicon. There are advantage of one over the other but anyone will probably be all you need.

Someone mentioned lateral motion. If you use Arca-Swiss compatible components you can loosen the clamp and slide the camera laterally some without moving the tripod.

There is one point that is not mentioned often and that is you can increase the depth of field by increasing the distance to the subject. You will have a smaller image on the sensor which you will need to enlarge more but resulting DOF will be greater. Image dimension on sensor goes down proportional to distance where depth of field increases by the square. Twice the distance will yield twice the depth of field when the subject is enlarged to be the same size in both cases.

Your camera has a high pixel density and coupled with a good lens this is an option to play with.

Have Fun!

John

[Stagecoach]

Bruce, I'll throw in another one with regard to a specific situation where I find the focus rail a major advantage.

I often shoot small bugs/critters in a studio type set-up indoors where I want to use the maximum magnification of the rig, e.g. with lens set at minimum focus and using a tripod.

Very often critters will move and if they come towards you there is no option but to move the camera/lens farther away from the critter to get/maintain focus and adjusting things with the focus rail is far easier than moving the entire tripod.

I also find that when at 1:1 and greater and working from a tripod I can achieve that critical focus faster by adjusting focus by movement of the focus rail than by lens rotation with moving critters.

As for rails, I have used the cheapest ebay model for years, take care to ensure my positioning takes account of the rigs CofG, understand it's limitations as with any bit of gear and find it's great for my needs.

Lastly, with respect to stacking it does not necessarily mean that the images will be superior to non stacked images or it's the only way to get 'decent' macro images. Quite the contrary, stacking often produces sterile images that totally lack in appeal if as so often done just because it can be.

Grahame

[rpcrowe]

John brought up something that jogged my memory. If you have an Arca Swiss Clamp on your tripod head, you can get a longer plate and use that as a pseudo-focusing rail...

Here is an example...
http://www.ebay.com/itm/140mm-5-5-QR...item43c35c4cea

This would give you about 140mm of movement. In order to utilize this concept, your Arca Clamp has to be mounted so that the channel is fore and aft rather than side to side. While the plate is mounted to the camera parallel to the lens. That way, you can loosen the clamp and slide the plate (with camera and lens) fore and aft.

If you have an Arca Clamp, this would give you some capability at a very low price... If you don't have an Arca Clamp on your tripod head, I would think about getting one - not just for macro work. The Arca Swiss system is the nest thing since sliced bread.

Whenever you are using a rail or any type of plate that shifts the center of gravity away from directly over the apex of your tripod, you need to be very careful that the camera and lens doesn't tip over...

[Mark von Kanel]

Hi Bruce,

I went through the same process as yourself and received lots of help on here, here are the 2 threads, might help if you have a read, but in short no you dont need rails, but they can help!

My Bee problems

soloution to my bee problems

[brucehughw]

Dan, John, Richard, Grahame, and Mark (and earlier posters),

Thanks so much for sharing your experience and expertise. You've given me much useful information, as well as some threads to delve into and the name of a local camera club that I was not familiar with.

I look forward to applying this information and sharing my results on CiC and elsewhere. CiC has such a knowledgeable, generous community of photographers, and no ads!

Thanks again, Bruce

[DanK]

Grahame,

Your post raises a really important point. There are two entirely different uses for a rail: making the focusing adjustments needed for image stacking (which is the main part of the thread, and what I was responding to), and getting the camera positioned correctly for the entire stack.

The latter can be a nuisance in macro work, even if the subject isn't moving. I often find that my initial framing is wrong, and I have to move the tripod or the subject, either of which messes up aspects of the framing other than the distance. For that purpose, I think a rail might make some of my work easier. I'll have to explore.

To deal with rotation in framing macro shots on a tripod, I use a Manfrotto "junior" geared head, which I have adadpted to fit arca-swiss plates by replacing the clamp with one sold by Hejnar (on eBay). This is a very bulky piece of equipment, but it makes the needed fine adjustments far easier to make, and it has negligible sag (hysteresis?) after being set.

The ideal for me would therefore be a rail that has an arca-swiss compatible plate on the bottom and an arca-swiss compatible clamp on the top. I'll have to look some over.

Dan