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View Full Version : Macro lens or extension tubes for Pentax?



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tnabbott
02-23-2013, 12:28 AM
I like the SMC 67 Macro 1:4 100mm with life size converter.

jcc
02-25-2013, 01:11 PM
I use a macro lens for "normal" close-up, a reversing ring or bellows/extension (usually on a 35mm or 50mm lens) for "closer" macro work, and a combination of a reversed lens with extension for "ultra" macro work.

RalphLambrecht
12-15-2013, 08:14 AM
The amount of extension needed is directly proportional to the focal length. Longer lenses (MF lenses are longer) thus need more extension than shorter lenses (like the ones used on 35 mm cameras and the even shorter ones used on sub-35 mm format digital sensor cameras) to reach the same degree of magnification.

Also, 35 mm format lenses are smaller, and fancy tricks, like not just using extension to reach a certain degree of magnification, but changing the focal length of the lens while focussing as well, are a lot cheaper then they would be if the lens would have to cover a larger format.

MF lenses are larger, thus put more weight on the focussing helicoid. This sets a mechanical limit to how far you can rack tsuch a thing out before it will start to sag under the strain.

So you will need rigid extension tubes sooner with larger formats than with smaller formats.

Now if all you want to record are three teeth at 1:1, and these fit inside a 35 mm frame, there is absolutely no reason to use a larger format. All you will get is more of what is next to the teeth, more of what you were not interested in.
If you want to photograph the same three teeth, but at a higher magnification, so the fill the larger 6x7 frame the same as they do the 35 mm frame, you will need a bigger, more cumbersome kit.

View camera's movements do offer advantages, because you can position the plane of focus more or less where you like. It is not necessary (as in cameras without movements) to have it paralel to the film plane. Can be of very great help to get more of the image in focus (and/or in depth of field).
Iagree. I was aware of movements from my view camera work when I got my Nikon bellows, which offer limited movements.T hey are still a big help!

pentaxpete
02-10-2014, 04:06 AM
I have a British 'BPM' Bellows unit with both PENTAX M42 and CANON FD flanges on it -- I use it a lot with my 105mm f4.5 E-Rokkor enlarging lens and it gives good results. When I got my 6x7 outfit in November 1980 I also got teh extension tube set and found it useful, then in about 2003 I got a 6x7 Mk II very cheap with the 135mm f4 SMC Macro-Takumar and found I needed a tube to get really close but the depth of field was very small due to the film size -- here is my Spotmatic with the bellows unit --
http://farm9.staticflickr.com/8232/8551125479_2bc0571e04.jpg (http://www.flickr.com/photos/25850987@N03/8551125479/)
PentaxBellows (http://www.flickr.com/photos/25850987@N03/8551125479/) by pentaxpete (http://www.flickr.com/people/25850987@N03/), on Flickr

narsuitus
03-19-2014, 01:20 PM
Macro lens or extension tubes ...

Which do you guys prefer?

I use them both and have no preference.

http://www.flickr.com/photos/11336821@N00/8469464382/

RalphLambrecht
03-21-2014, 11:01 PM
Which do you guys prefer? I just used my extension tubes for the first time today and I'm not the happiest. I don't know why, but when I used extension tubes with my 35mm rig, it was much easier to find the sweet spot. I used them on my 200 and 75 in different stack ups.

Now with the 120mm Macro lens can you focus all the way out to infinity and use it as a portrait lens also? Could somebody tell me what you think about that lens or the 135mm for the 67?

I'm about ready to send this set of tubes back to KEH and exchange it for a macro lens.

call SK Grimes and have then make you an adaptor for your enlarging lrns to fit the camera.That's the way I got the best optical quality.

Fritzenpapa
03-28-2014, 12:33 AM
Hi,
I use the Pentax 67II with a Macro - TTL-Ringlight and I do mostly Macro photos. I have the Macro 135mm lens, extension tubes and I newly accomplished this by the original Pentax 6x7 bellows. 135mm without tubes is great for portraits, 135mm with the whole set of tubes gets you down to 1:1 and 135mm with bellows even beyond. Great advantage of the bellows over extension tubes: a double cable release allows automatic diaphragm. If you like to get even closer, you can turn arount the front board of the bellows, which allows you to use the standard 105mm lens (or any other lens with a 67mm filter size) in retro position. With a double cable release, even then with automatic diaphragm. Great advantage. The bellows for the 6x7 has a much longer extension then any other 35mm or MF bellows on the market (350mm!!). If you use the Pentax 645/645N/645Nii, iŽd recommend the 6x7 bellows over the 645 bellows for its much longer extension.
In short: For Pentax MF Macro work 135mm macro lens and tubes and bellows (of course you can add enlarger lenses with that one aswell).

RalphLambrecht
03-28-2014, 06:53 AM
in general a dedicatedmacro lensshould deliver the best optical quality and the diopter lens should be the worst withe tubes somewhere in betweenbut I was positively surprised by the Carl Zeiss diopter for the Hasselblad.Those guys know what they are doing!I'm looking forward to check up on the idea of using enlarger lenses for close-up photography.You can get SKGrimes to make you an adaptor that doesn't break the bank but delivers superior quality with your enlarger lens(just a theory of mine at this point)

Dan Fromm
03-28-2014, 07:20 AM
in general a dedicatedmacro lensshould deliver the best optical quality and the diopter lens should be the worst withe tubes somewhere in betweenbut I was positively surprised by the Carl Zeiss diopter for the Hasselblad.Those guys know what they are doing!I'm looking forward to check up on the idea of using enlarger lenses for close-up photography.You can get SKGrimes to make you an adaptor that doesn't break the bank but delivers superior quality with your enlarger lens(just a theory of mine at this point)

Ralph, back when I was a beginning photographer Modern Photography ran educational articles on roughly a two year cycle. Every other year they published a piece "Extension tubes of diopters -- which is better?" The answer never changed. Which is better depended on the lens. The only way to know which was better with the lens in hand was to try both. MP is long gone but I don't think the answer has changed.

Re enlarging lenses for closeup, the results depend on the enlarging lens and on the magnification. Until I read Schneider's documentation and did some testing I believed that a Componon-S would be better for closeup work that a plain Componon and that a plain Componon would be better than a Comparon. All mounted facing normally, all used in the range 1:1 - 1:4. Turns out that the Componon-S is indeed a bit better than a plain Componon, but at that range of magnifications a Comparon is the best of the three. This because Componons are optimized for making larger prints (= taking at lower magnifications) than the humble Comparon. Who'd have thought it?

As for dedicated macro lenses, far and away the best ~100 mm macro lens I've ever used that will cover 2x3 from 1:5 up is a 100/6.3 Neupolar. So you're right. But and however, my relatively humble 4"/5.6 Enlarging Pro Raptar is as good at the same magnifications from f/11 (set, not effective) down. So you're wrong.

The moral of all this is that generalizations based on general principles are risky.

benveniste
03-29-2014, 09:53 AM
Ralph, back when I was a beginning photographer Modern Photography ran educational articles on roughly a two year cycle. Every other year they published a piece "Extension tubes of diopters -- which is better?" The answer never changed. Which is better depended on the lens. The only way to know which was better with the lens in hand was to try both. MP is long gone but I don't think the answer has changed.

Since this thread is asking about the Pentax 67, I'm not sure that my experience with the Pentax 645 is germane, but here goes. I own the Pentax 120mm AF macro for that system, a set of extension tubes, (13.3, 26.6, and 39.9mm), and a Marumi 330 +3 diopter achromat in 67mm. I've printed "eye-sharp" 24x30" prints at 1.5x magnification using both approaches. On a copy stand, I typically use the extension tubes, but on a tripod I chose the close-up lens because the camera balance was better.

I've used the 75mm f/2.8 with the short tube for some "near macro" work, as the 5.5:1 reproduction ratio of that lens can be limiting at times. Before I got the 120mm, I even tried all three tubes once. The results were reasonable, but I honestly feel the 120mm gives better results and is far more convenient to use.

So compared to a dedicated macro lens, whether you choose close-up lenses or extension tubes you're trading off convenience and some optical performance for cost. On "normal" lenses, I suggest using tubes. But once you reach focal lengths of 135mm or so, I suggest using close-up lenses instead.