[bassek]

Thanks for all the input, I expect to pick it up next week. It's the Auto Bellows M-type.

Do you shoot fully open or way stopped down (closer to f22) for a larger DoF?
At least now I have use for my M50/1.7 again!

Seb

[Not a Number]

I normally shoot two stops before or f/11 on most Pentax lenses (max f/22). The added DOF helps but there is a trade-off because of defraction. It also depends on the lighting too.

[stevebrot]

Do you shoot fully open or way stopped down (closer to f22) for a larger DoF?
At least now I have use for my M50/1.7 again!

You will have to stop down to get DOF. There is a reason why many (most? all?) macro lenses stop down the f/32. OTOH, maybe you don't want DOF! It is all for fun and creativity, right?


Steve

[Bob from Aus]

get some near fully frame pictures of 1/8W axial lead resistors.

As one would naturally do

---------- Post added 04-19-14 at 09:15 AM ----------

normally shoot two stops before or f/11 on most Pentax lenses

I find I go much bellow F11the image isn't as sharp so any extra depth of field isn't relevant.

[baro-nite]

Do you shoot fully open or way stopped down

Almost never the former, only rarely the latter. Increasing the magnification also increases the effective f-number, so that diffraction becomes an issue at wider apertures than one might expect. For magnifications of 1:1 and below you will usually get good results stopping down to f/11 to f/16. For higher magnifications that doesn't always work so well. Hence the popularity of focus stacking for high-magnification work.

[tim60]

As one would naturally do.

I needed it, along with some less extreme macro pictures of larger resistors for a lecture I was going to give.

Reminds me, completely irrelevant to this thread: I once took a picture of a billboard in Albuquerque NM with the tag line on a picture of a burger: "Who needs salad? Blake's lotaburger". A friend from Singapore, whom I met when he was working at RAH, used it for one of his public health lectures in Singapore.

[Not a Number]

The website tested a variety of lenses from bellows macros to microscope objectives. Only one Pentax (100mm f/4 M42 bellows lens) though. Gives the "sweet spot" (sharpest f-stop setting) for lenses tested.

Macro Photography Lens Tests

[TaoMaas]

I bid on a bellows unit and meanwhile I wonder what lens would be the most suitable.

The great thing about a bellows is that you can put pretty much anything on there and use it for macro purposes. I own the bellows you won and I originally bought it for use with my M135 prime. That made a great combination for shooting flowers and such. These days, I'm using the bellows with a 100mm enlarging lens most of the time. That works pretty well, but I wouldn't say it's significantly better than my dedicated 100mm macro lens. However, the thing about owning a bellows is its flexibility. A macro lens is what it is, but a bellows expands the capabilities of ALL your lenses. If I were you, I'd think about adding a reversing ring and a focusing rail to your arsenal now.

[baro-nite]

I'd think about adding a reversing ring and a focusing rail to your arsenal now.

No need for the reversing ring with the OP's bellows, as long as you have the double cable release that normally comes with it. The front standard is reversible. This allows you to focus wide open.

[TaoMaas]

The front standard is reversible. This allows you to focus wide open.

Are you serious? I've had this thing for 20+ years and never tried that because I didn't have the need to go to that magnification. Still, that's good to know! Thanks!

[baro-nite]

Are you serious? I've had this thing for 20+ years and never tried that because I didn't have the need to go to that magnification. Still, that's good to know! Thanks!

It's a nice feature. Also gives you additional options for adding a hood or even filters. (It's why the scale has a "normal" and a "reverse" side.) Now that I think about you don't particularly need the double cable release, either, for use with a camera that doesn't work with a mechanical cable release -- any old-school release should do. Although it would be very cool to hybridize the double release to make it compatible with Pentax DSLRs.

[Not a Number]

I don't know about the Auto Bellow M but the K and A the cable release socket is incorporated into a locking button. No cable is needed - just push the button in and twist it to lock. Twist it the other way to unlock it.

The reversible standard is very cleverly designed as noted. It maintains the stop-down features and the rear element and aperture mechanisms are not exposed or at least are recessed. And there is a filter thread.

Here is the Auto Bellow (M42) with the front standard reversed with the Super-Multi-Coated Takumar 50mm f/4 Macro attached:

[TaoMaas]

(It's why the scale has a "normal" and a "reverse" side.)

I never really looked at them that close. I think my scales are still in the plastic bag they came in. lol

[Kayaker-J]

Thanks, everyone, for the very helpful group of responses to my subtopic inquiry regarding the M42 version of the Pentax bellows system. I'm happy to have received the cautions up front; and the bellows set-up photos added useful clarity to the discussion, so thanks for those. Plus the suggested "Macro Photography Lens Tests" link is quite something -- there's a wealth of information there, not only as regards results for specific lenses, but also as a source of very accessible data from which the big picture can be gleaned. Having the S-M-C Takumar 50, Auto Nikkor 55mm/3.5, Vivitar Series 1 90mm/2.5, and the K28mm/3.5, plus a pretty nice Velbon focusing rail, I figure from your suggestions that I should be in pretty good shape to get started experimenting with bellows work.

[baro-nite]

I don't know about the Auto Bellow M but the K and A the cable release socket is incorporated into a locking button. No cable is needed - just push the button in and twist it to lock. Twist it the other way to unlock it.

I think they all have the same socket/button. I prefer the cable because otherwise it takes a fairly hefty push of the button to stop down, a greater risk of moving the camera.

Plus the suggested "Macro Photography Lens Tests" link is quite something -- there's a wealth of information there, not only as regards results for specific lenses, but also as a source of very accessible data from which the big picture can be gleaned. Having the S-M-C Takumar 50, Auto Nikkor 55mm/3.5, Vivitar Series 1 90mm/2.5, and the K35mm/3.5, plus a pretty nice Velbon focusing rail, I figure from your suggestions that I should be in pretty good shape to get started experimenting with bellows work.

I'm a fan of the coinimaging.com tests too; very useful info. You certainly have all you need to get going with a very wide range of magnifications. I was a bit disappointed at the performance of the K35/3.5 for reversed high-magnification macro, given how sharp a lens it is used normally. The K28/3.5 is much better.