What is the Zone VI modified pentax spotmeter?

[walter23]

What's the modification here? These things go for a small fortune on ebay, and the only noticable thing is the little zone system paper strip that's always taped to the barrel. Anybody know what this modification is?

[David Karp]

Check the archives on this one. There have been a ton of postings on this, and different perspectives on whether the extras on the Zone VI version are worthwhile.

[Eric Woodbury]

The modification results in the meter 'seeing' the same as BW film, thus metering through filters for proper filter factors is possible and metering scenes with strong color accurately. Additional baffles were once included, too, to increase contrast in tough lighting situations. I believe the modifications have changed over the years, but if this changed the result, I do not know.

Photogs I know considered the extra cost worth it.

[Peter Lewin]

Here's a pretty good article by Paul Butzi on the Z6 Modified Meter. As an earlier poster mentioned, there are different opinions on whether the modifications are effective, so Mr. Butzi's view may be contradicted by others. For what its worth, I have and use the modified meter, but I've never tested it against an unmodified Pentax. http://www.butzi.net/articles/zone%2...worth%20it.htm

[Kirk Gittings]

You will note in Butzi's update of his article http://www.butzi.net/articles/zone%20VI%20reprise.htm
numerous references to my claims that the modifications are worth it. Understand, I am a working photographer and I have no time for equipment that doesn't perform, but because I am an actual working photographer I don't have the time (or the interest) to respond in kind to Paul's extensive testing. Mine work as per Alan Ross' claims and that is enough for me. I currently have two, one modified and one originally was regular when I got it. The modified out performed the regular so I had it modified too. It now works as well as the originally modified one. These are the 4th and fifth Pentax Spot meters I have owned and the only ones modified. They do the job. I can now meter accurately thru filters which I could not do as well on any of the unmodified meters. If these were stolen, I would replace them with ZVI modified meters.

Personally, in photography, when I am confronted with contradictory technical information, I look at the actual work of the claimants. Alan Ross and Richard Ritter are perfectionists and it shows in their work. They also have no time for crap that doesn't do the job.

[Brian Ellis]

The paper strip has nothing to do with the Zone VI modifications. The strip can be bought from Calumet (or used to be, I haven't checked to see if they still sell it or not) for about $5 and is just an easy way of applying the zone system with this meter. The modifications, on the other hand, involve physical changes to the meter. Here's what Zone VI Studios said they did in making the modifications: Installation of superior photo-electric cells; installation of a series of step-down baffles to eliminate flare; installation of a braod-spectrum (ultra-black) infrared absorbent coating to eliminate reflections; design and installation of four corrective filters, intended to match the meter's spectral response to the spectral response of the film.

I've owned used a modified Pentax digital spot meter for many years. I have no idea whether it performs better than an unmodified meter. I accepted Zone VI Studio's claims for it on faith.

[Ole Tjugen]

... design and installation of four corrective filters, intended to match the meter's spectral response to the spectral response of the film. ...

Which film? And would it be equally well matched to other films?

All BW films have slightly different spectral response. IMO it makes more sense to learn the characteristics of the film you are using than to buy a meter perfectly matched to one specific film.

[Per Berntsen]

Which film? And would it be equally well matched to other films?

I believe it was designed to match Tri-X 4 x 5. (Fred Picker's favorite) I have been using it with T-Max 100 4 x 5 with great success for many years. When the T-Max films came out, I remember that they would render a blue sky darker (more natural-looking) than any other film I'd used. So that may be the biggest difference between these two films. In general, I would have thought that the differences in spectral response between films would be negligible when using this meter.

The best thing about the Zone VI Modified in my opinion, is that its response to green (at least in nature) is much more correct than an unmodified meter. Before I got this meter, I was using an umodified one, and grass and foliage would often come out about 1 zone darker than expected. The modified meter would provide a correct reading of these subjects, and I could adjust exposure and/or development to get what I wanted.
Another advantage is that this meter will give a correct reading through strongly colored filters.

[Alan Rabe]

"I believe it was designed to match Tri-X 4 x 5."
IN another thread by Richard Ritter he debunks this claim. It is true that Fred said to do it to Tri-x but they knew better and did an average of all the primary films available at that time.

[Helen Bach]

Which film? And would it be equally well matched to other films?

All BW films have slightly different spectral response. IMO it makes more sense to learn the characteristics of the film you are using than to buy a meter perfectly matched to one specific film.

Yes, it appears to be possible to get well exposed pictures with unmodified meters.

The differences in the spectral responses of B&W films are most marked at the red end of the spectrum, which is probably the most critical end for metering through filters. Making the blue end of the meter's response more like that of film, and removing the green peak could be worthwhile though. (Side note: when you look at the spectral sensitivity of B&W film you need to bear in mind that Kodak publish equal energy curves, and almost everyone else publishes wedge spectrograms made in tungsten light. This leads to a very different shape, and comparing the two can be very misleading.)

My musings on a DIY kit were just musings. Is there a demand? I wasn't asking from a commercial viewpoint, but because it would be an interesting side project. I have modified a Pentax Digital Spotmeter to mimick HIE. Even expensive filter material is cheap for the amount needed to modify a meter - you just need to share out bits of the 50 mm squares among your friends. Deciding on the filter pack isn't rocket science. I wrote some software a while ago for designing optimum filter packs for another purpose, but it could be adapted for mimicking film spectral response using commercially available filters. Finding time is a different matter, of course, and if nobody wanted it, not even me, I wouldn't take this any further. I don't wish to tread on anyone's toes either.

Best,
Helen