Which lens should I get: 135 f/4, 165 f/2.8, or 165 f/4?

I need a lens in the mild telephoto range to complement the 55mm f/4, which I'm definitely getting. I'm considering getting the 135 f/4 macro or the 165 f/2.8. Which lens offers more consistent sharpness/performance from wide open to stopped down and center and corners? In general, how do macro lenses with their flat field perform as portrait lenses? How about at infinity?

 

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Thank you for your input.

You did not specify which camera you are using, but I assume from the focal length/f-stop combinations that you have mentioned that you are using a Pentax 67.

 

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I have both the 55/4 and 135/4 macro lenses for the Pentax 67. Both of them are outstanding lenses. I decided to skip the 105mm and 165mm lenses in favor of the 135. I use it as a long normal, short portrait, and macro lens. It does very well at all of these jobs. I have heard some say that you need a short extension tube to get close-cropped head shots with the 165mm, but that is not problem with the 135 thanks to its close focusing abilities.

 

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I cannot comment on the optical performance of the 135mm vs 165mm because I do not own both of them. From what I can tell, though, the 135mm is one of the sharpest lenses around.

 

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Joel Collins | jwc3@mindspring.com | http://www.mindspring.com/~jwc3

I'm sorry about that. Yes, I'm referring to Pentax 67 lenses.

William

 

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I've got the 165 L/S, I had the the 165 2.8 previously but decided to change to the leaf shutter because I figured that I wanted an option for fill in flash. The leaf shutter lens is also smaller and lighter than the 2.8 but slightly wider, quality I wise I have no complaints with either.

 

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The big problem with both lenses (and indeed most pentax 67 lenses) is that they do not focus close enough for a tight head shot, you end up cropping to about a 645 neg. Why pentax designed a portrait lens like this is beyond me (anybody know ?). I am toying with getting a 135mm lens for this reason but am worried by that it is only about 70mm in 35mm format wheras I would use a 90/100mm lens out of choice on a 35mm camera.

 

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Tapas

I have had great success using the 135 for tight portraits. It does not exhibit the type of distortion one would expect with a 70mm lens on a 35mm camera. I saw this explained such that the closer you focus with the 135, the longer the 35mm equivalent, out to about 85 or 90mm!

Unfortantely, I can't remember the details or the math, but it made sense at the time an seems bourne out by my experience. If I could only keep 1 lens for my 67, it would be the 135.

 

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Regards, Jim

You might want to consider the new version 200mm f/4. With 2x magnification, it is more traditional for potraits than a 135. It is quite sharp and can be used for macro with extention tubes or helicoid. It works well for landscapes also.

Steve

 

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Using the 200mm seems interesting - can you get a tight headshot with it or does it need extension tubes ? How is it handheld ?

 

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Tapas

How does the 200mm perform wide open?

Re: the 200 mm lens and extension tubes, see <a href="http://db.photo.net/bboard/q-and-a-fetch-msg.tcl?msg_id=000Dy3">http://db.photo.net/bboard/q-and-a-fetch-msg.tcl?msg_id=000Dy3</a>.

Tapa & William, The 200mm is fairly good wide open but I would recommend shooting at f/5.6 instead. This new design has an extra element for better aberration correction and will focus down to 1.5 meters as opposed to 2.5 meters with the old design. This makes a huge difference with head shots. The old version couldn't do head shots very well while the new one can. You shouldn't need an extension tube for close portraits with the new version. Avoid the old four element model. BTW, all Pentax lenses are flat field, otherwise the film would have to be curved. SR

My testing and experience with the NEW 200/f4 is that it is pretty easy to hand hold and balances well with the body. The sharpest F-stops are in the 5.6 -16 range. Optimum appears to be f11. F22 drops a few l/mm.

In response to Jim Sabos post about the effective focal length

changing as you focus closer :

 

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Focusing any lens closer by racking out the whole lens assembly

does *not* change the focal length, only the angle of view, as

is perhaps better known to LF folks. In fact this results in

*reducing* the angle of view, making the lens seem more like a

longer focal length lens! However, most 'Macro' lenses

use Internal focusing which provides both extension and a

*reduction* in focal length so as to retain a comparable angle

of view as the lens would have at infinity focus.

 

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The *math* is presumably quite lens dependant, hence no clear

rules of thumb.

Even neglecting internal focusing, the focal length you need to achieve the same angle of view with a different format depends on the magnification and becomes significant at magnifcations greater than about 1/10.

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See <a href="http://db.photo.net/bboard/q-and-a-fetch-msg.tcl?msg_id=000BT6">http://db.photo.net/bboard/q-and-a-fetch-msg.tcl?msg_id=000BT6</a> for the details.