[Venturi]

I'm looking for a good explanation of the differences between K-mount Pentax Bellows setups. From what I have garnered reading the Lenses & Accessories catalog from the period (my copy is from 1984) and Dimitrov's site there are three (?) models?

Auto Bellows M, Auto Bellows A - are these actually two different models or just different names for the same thing? If they're different I'd like to know how.

Bellows Unit III: Slightly shorter range and all manual aperture control - no DOF preview controls?

Thanks in advance for any info!

[stevebrot]

There are at least three and probably up to five different Pentax-brand K-mount bellows.

The design variants are:

• Auto aperture support through dual cable release
• Integrated focus rail (over/under), some with geared adjust and some without
• Length of bellows extention

I own the Bellows-K (not on your list). It lacks the auto aperture support, but has the integrated focus rail. Unfortunately, the focus rail is not gear driven. I am not sure, but I think it may be one of the more compact versions.

Here is a photo:



Steve

[Venturi]

Thanks, Steve.

"Auto aperture support through dual cable release" that's what has me a bit confused with the Auto Bellows A/M. Do both (are they different models?) do this? I've got a line on an Auto Bellows M and also a Bellows Unit III and am trying figure out which one - if either - is what I want.

[stevebrot]

Thanks, Steve.

"Auto aperture support through dual cable release" that's what has me a bit confused with the Auto Bellows A/M. Do both (are they different models?) do this? I've got a line on an Auto Bellows M and also a Bellows Unit III and am trying figure out which one - if either - is what I want.

If it says "Auto", it supports the dual release. Whether a functional release is included with the bellows (has not been lost or damaged) is an entirely different question!

If I were to replace my unit, the Bellows M would be my first choice.

Steve

[Venturi]

Muchos Gratias

[OregonJim]

I have the Vivitar Bellows System. What's nice about it is that both ends are T-Mounts. Thus, you can use it with any camera or lens for which a T-Mount adapter is available (virtually all of them). All adjustments are geared. It also has a slide copier, a focus rail, and macrophoto stand (same as a microscope stage). I was lucky enough to get one that had all the T-Mount adapters I needed, but T-Mounts are cheap.

The Vivitars usually go for about $50 US, and are just as solidy built as the Pentax ones.

Edit: Just did some looking, and, like Pentax, there are several Vivitar variants. The one I'm describing is (I believe) the only dual-rail version. All the others seem to be single-rail and lack the T-Mount feature.