Macro lenses vs long telephoto zoom or normal lens with extension tubes

[ksklo]

I have a question regarding the difference between the two setups for taking closeup flower shots. While macro lenses can go 1:1 or even more with extension tubes, what exactly are the differences in using either a long telephoto zoom or a standard 50mm lens and mount on top some extension tubes.

I realize that using a telephoto lens with extension tubes will give you a bit more working distance as opposed to a 1 to 1 macro, but what else is there for us to pay attention to, apart from the inconvenience of changing and adjusting the combination of extension tubes in order to achieve the required focusing point? And what about depth of field?

I apologize as this question may seem very broad but I would like to first get a general idea before narrowing the scope of my question. Thanks.

Ken

 

[pkipnis]

It's a good question. It brings up the difference between flat field macro lenses and telephoto lenses, which have a flatter field because of the inherent design. When I was a "young" photographer, we often reversed the 50mm standard lenses to get as flat a field as possible as there were few if any real Macro lenses made. The first I remember was from Pentax followed by Nikon. Most Macro lenses are designed to produce images without barreling or pincushioning on a single axis, hopefully the focal point. As one who cheats using long telephotos with tubes for portraiture and people photos, the macro images are just OK. I do have a 60mm makro plannar, which is hands down excellent despite having a short working distance. But I like the image better as compared to the 100 makro, which is likely the finest 35mm lens, made (my choice, no hard data)
The depth of field issue has to be addressed two ways. The obvious is focus on the central object and let everything else fall away. I prefer to use the optimum F-stop and hyperfocal to include (or exclude) what I want in focus. Sounds trivial but can sometimes be daunting. Lets hear from others

 

[nelsonpoon]

Ken:

I used bellow with Carl Ziss s-planar 1.4 f=100mm lenses to take 1:1 photo, f32 with flash to increase the depth of field. And also used extension tube with fix lenses and zoom lenses.
My opinion is that, just use what ever you feel confortable. When take macro picture, depth of field may only half inch to one inch with f-4, if use f-22, depth field only increase to 2 to 4 inches.

Nelson

 

[spluff]

Ken,

There is a formula (which unfortunatly I cannot remember) that incorporates the focal length of your lens with the depth of your extension tube to provide you with amount of magnification acheived.

So for a 50mm with, say a 13mm extension tube, the magnification you acheive is greater than using, say, a 200mm lens. And if you use a 28mm lens, you get even greater magnification.

Hope that makes sense!!

Cheers, Saras

 

[ksklo]

Thanks guys for your inputs. Let me expand the discussion by stating my question differently.

If you have both extension tubes and macro lenses, under what circumstances would you choose one over the other? In other words what are the limitations of each of these setups? And finaly, would the quality of images produced by extension tubes mounted on regular lenses be compromised compared to closeup work produced by macro specific designed lenses?

Ken

 

[daniel_g]

If you have a two lenses of equal focal lengths (more or less) and you want to do close ups, always chose the macro for better image quality. Optical aberrations are corrected for closer focussing distances in macro lenses as compared to "normal" lenses, the latter being usually opitmized for infinity focus. Compare for instance the MTF data for the 100 mm Macro and the 100 mm regular CZ lens.

An other question is perspective. There are some focal lenghts for which there is no macro version. I recently played with a 13 mm ring on the 21 to get a small flower with proportionally increased flower compared to stem and leaves. Although the 21 by itself is stunning, there was significant (IMHO, unacceptable) image degradation when used with the extension tube. The focal plane is also approximately 2-3 mm in front of the front element of the lens.

I also use extension tubes with the 180/2.8 for reptiles (rattle snake portraits). With Contax, there is no 200 mm macro lens, so you have to improvise a bit. It is not a great set-up as the 180 lacks a tripod cl&. Anyone made a cl& to go around the extension rings?

If you want to go into seriously high mag (>3:1) then you may either go with luminar lenses or reverse a regular one, so that the assymmetry of the regular lens reflects the assymmetry of short object distance (lens to subject) and large image distance (lens to film). The Contax bellows is not that well constructed for reversing lenses, as the lens behind the front standart, as opposed to mounted with a reversal ring (camera bayonnet to filter ring).

[As anyone made a reversal ring? Think of supergluing a step-up ring on a 7 mm extension tube: any thoughts?]

The problem with the front standard is that the little image distance is challenging to get light onto the subject, so the 5 mm of the front standard rob precious light.

Because of lighting problems, you may also prefer the Luminars, as they have a smaller diameter of the lens barrel, and have a tapered front end: you get more light on to the subject, and also more directly, which will reduce undesirable strong shaddows.

I have also been fiddling around with stacking a 50/1.4 on the 100 mm macro for 3:1 work. Only problem is some vignetting at prime lens settings between infinity focus and 1:3 magnification. Otherwise works quite well.

Enough all right. Daniel

 

[nelsonpoon]

Ken:

For taking professional close up photo, Bellows with CZ S-Planar f-1.4, 100mm lenses can provides full range of depth of field and best photo quanlity.

If you insist use extension tube, you may use the variable length extension tube, it is more flexable to take a different ratio of image with fix length lenses.

Nelson

 

[rico1]

Nelson, the SP100 looks like an astonishing lens from the MTF. It also appears optimized for 1:4, which is very nice for flowers. Unfortunately, it is exceedingly hard to find (observed just once on EBay in the last year). After failing with the P100 due to close-focus limitations, I bought the SP60 for flowers (the MP100 is more expensive).

I have two questions for the CZ macro experts. First, do the bellows of the SP100 allow tilt movement? Second, if I mount the SP60 to the standard bellows, what is my long working distance?

 

[daniel_g]

The perspective control functions of the bellows are more or less independent of the lens you mount on it. The one caveat is image circle that the lens projects. I do not have any data on image circle for various CZ lenses (except the 35PC), but assume that they are more or less the same.

Second, the perspective control functions do not work at very little bellows extension: there is no room to allow the front standart to be swung/shifted, if the front and the rear standard are very close together.

For any given magnification (say life size = 1:1) the bellows extension is proportional to the focal length of the lens: 60 mm MacroPlanar [Rico: I trust you meant MP60, not SP60; at least I'm not familiar with a SP60] at 1:1 will require 60 mm bellows extension; a the MP100/SP100 will require 100 mm bellows extension (all at infinity focus of the lens). Accordingly, you get more freedom with perspective control with longer focal length lenses (you also get different angles of view with different lenses).

Re "tilt": Considering you mount the camera in landscape format on the bellows, the movement is lateral, and there is also lateral shift available (i.e., rotational and linear movement is in the same direction). You can turn the whole set up 90 degrees to get up-down movements; though under no circumstances can you get movements in all four directions as with a rail-type large format camera. The rear standard is fixed and the camera can be rotated 90 degrees on the rear standard.

For a given lens, working distance will be the same as when you use the helical thread on the lens. The only thing that matters is the final magnification, which determines the working distance. If you want to increase working distance, then get the longer focal length lens.

I have owned a bunch of macro lenses over the 20 years or so. I started with an OM Z50, then got the OM Z90 (also got the symmetrical OM Z80), and use a Pentax LX with AFM100 for underwater, and now have the MP100. For regular macro, I mostly (>80%) use the 100 mm range. Only when I consider perspective or foreground/background ratios (get flower head plus whole plant) then I use a 50 or even the D21 (should eventually get the 28, still building the system).

For further info, Constant's book on Macrophotography from Focal Press is IMHO the best on the market. Ray's tome (Applied Photographic Optics, now 3rd ed) also from Focal Press has a lot of info on optics and is a gem (though a tough read).

Nelson: you mention a "flexible extension tube". I used the OM auto extension tube 65-113 mm and loved it with the OM Z80. Is there something similar for CZ? Or did you use "flexible extension tube" as an alternative descriptor for a bellows system?

Hope that helps. Daniel

 

[schulz]

I am new to this site.. If this post is in the wrong area.. just tell me where to go....

About a year ago I sold a bunch of Nikon stuff, a complete Bronice system and a view camera... all to Go Digital in my wedding business. Digital is wonderful for weddings.

BUT I just don't like it for me. A few weeks ago, after careful research, I purchased two Contax bodies and 3 lenses. WOW, I don't need to tell you folks what a great deal it was.

Now what... Where does one get parts?? On my maiden voyage with the 167 I lost the bottom plate,where the batterys go,. KEH has no clue where to get one.

Where does one get such things.

schulz@johnschulz.com

John