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neil poulsen
7-Jul-2014, 08:16
Now that I'm changing developers, I've been in the process of re-doing my calibrations. I have both a Pentax V 1 deg. analog meter with the Zone VI modification, and some time ago, I snapped up the digital version off of ebay for an inexpensive price.

I thought that I would convey a quick observation about these two meters. I think that for use in the field, there's not a lot of practical difference between the analog and digital versions. (Setting aside the Zone VI mod, which has it's own advantages.) But at least for the way I do calibrations, the digital version doesn't cut it. In adjusting the intensity of my target, I need the more exact readings from an analog meter. I draw density curves (film density versus target exposure) from the data I collect, and I can obtain relatively accurate curves using the analog meter.

To explain a little, the digital version gives the exposure number, and then one or two little circles light up, if the intensity is 1 or 2 thirds above that number. So, the best reading that can be captured with the digital version is to the nearest third, and even then, it can be a little tricky.

Because of a lucky circumstance, I have both types of meters. But with the above consideration, if I had to pick one over the other, it would be the analog version.

ic-racer
7-Jul-2014, 17:56
The manufacturer's claimed precision is 1/3 stop for both meters.

Alan Gales
7-Jul-2014, 18:06
Half a stop is accurate enough for me. What am I missing?

ROL
7-Jul-2014, 18:18
Half a stop is accurate enough for me. What am I missing?

Perhaps the same thing as I. OP shooting color trannies?

Leszek Vogt
7-Jul-2014, 19:48
It's good that you can compare the readings. The only thing is, that if your analog goes ker-plunk you may not be able to revive it. When I was shopping for a meter recently, I asked Quality Light Metric and they advised me to stay away from Pentax analog, since the parts are no longer available. Anyway, you might want to lean on the digital little more and squeeze every **Lux** you can or perhaps get another analog (just in case) ? Just saying...

Les

jbenedict
7-Jul-2014, 20:24
1/3 stop one way or the other could be in the shutter so I'm not entirely sure that it makes that much of a difference Pentax analog vs digital. A shutter you fire off a few dozen or so times a year might be fine in the summer and sluggish in the winter, at least up here in the Northern climbs. I guess that I am careful and try to be consistent but I'm not a scientist.

Jeff

Bill Burk
7-Jul-2014, 21:11
I think it's fair to explain how accurate and precise the meters are.

Used as a densitometer, you only get 0.1 precision while common densitometers can do 0.01 - so the analog meter is ten times coarser...

But the analog meter is much easier to use to adjust artificial lights for even illumination.

You get to watch the needle as you make changes and you can stop when you hit the mark.

If only the lights would cooperate and fill the target evenly... I can never seem to get perfect coverage.

AA+
8-Jul-2014, 13:53
I dropped my Pentax Digital without case on a concrete sidewalk from 4 feet high. No damage. My buddy dropped his analogue spot meter on my kitchen floor from 2 feet high. All the works came out.

Best wishes --- Allen

john borrelli
8-Jul-2014, 17:10
You might find the digital meter to be more accurate in low light. The digital is definitely lighter than the analog versions. I own the digital version but I also owned an older analog version, the fun thing about the analog version is all of the buttons and functions which reminded me of all the functions on some of the old small format cameras. I liked the analog meter.

neil poulsen
9-Jul-2014, 05:03
I think it's fair to explain how accurate and precise the meters are.

Used as a densitometer, you only get 0.1 precision while common densitometers can do 0.01 - so the analog meter is ten times coarser...

But the analog meter is much easier to use to adjust artificial lights for even illumination.

You get to watch the needle as you make changes and you can stop when you hit the mark.

If only the lights would cooperate and fill the target evenly... I can never seem to get perfect coverage.

Exactly. The target I use consists of a sheet of translucent white plastic separated by a distance of 3/4" from a sheet of frosted glass. This is illuminated from behind (the frosted glass) by two blue, 200 watt daylight corrected incandescent bulbs. Using the analog meter, and adjusting the distance of the bulbs behind the two sheets of glass, I can achieve greater accuracy when adjusting the intensity of the target. This improvement in accuracy is very useful in how I do calibrations.

But as I say, in the field, I doubt that there's much practical difference between the two meters.


It's good that you can compare the readings. The only thing is, that if your analog goes ker-plunk you may not be able to revive it. When I was shopping for a meter recently, I asked Quality Light Metric and they advised me to stay away from Pentax analog, since the parts are no longer available. Anyway, you might want to lean on the digital little more and squeeze every **Lux** you can or perhaps get another analog (just in case) ? Just saying...

Les

It would probably be optimum for me to get a Zone VI modified digital meter for the field, and keep my analog at home for calibrations. Expensive, though.