Sunday
17 February 2008
5 Comments

Pentax Digital Spotmeter + Mod

Up until recently, I have been using a Sekonic L-558 Dual Master which has been accurate but ultimately unsatisfying and often annoying in use. My main complaint about the Sekonic is that it doesn’t make it easy to use the zone system and to check relative exposures. Pretty much every large format photographer of note tends to use the Pentax Digital Spotmeter (PDS) or some equivalent (e.g. a simple EV meter with a mechanical calculator).

The advantage of the mechanical calculator on the PDS is that it makes it simple to look up alternative exposure settings. It’s also very easy to apply offsets.

The only missing part of the equation is using the zone system (if you can’t find a neutral grey, you can’t use the default exposure reading). There is a sticker made by Zone VI which shows all of the zone levels from 1 to 9. However this only really works for high range black and white film with a dynamic range of 8 or 9 stops. (The picture below is from a review of the Zone VI mod at http://www.butzi.net/reviews/light_meters.htm

With Velvia 50, you only really have 5 stops of range, which with a bit of research I’m presuming is +2.3 to -2.7. So what is a person to do? Make my own that’s what! So I made up a template using Macromedia Fireworks (after measuring the width of a stop on the meter and the depth of space I could use). The following is a jpg you can use to print out if you like).

Once this was made up I printed it out on stickyback paper and then covered the top with a strong, clear sellotape (for water and smudge resistance). Clipping off the corners to try to stop it getting knocked off and it all seems to be OK.

The idea is that you find a part of the scene you want to be a certain zone and take a measurement from it. Then place that EV reading against the zone on the sticker.

NB: I should add that the in the photo above, the scale isn’t centred on 8 and hence it looks like zone XI is 2 2/3 rather than the 2 1/3 I intended it to be.. I should also add that I’m not 100% sure that 2 1/3 isn’t totally transparent (I’ve got a feeling it probably is – or rather even if it’s not, if you read 2 1/3 with a light meter and there is any texture, the highlights will be above 2 1/3 and hence totally transparent)

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5 Responses to “Pentax Digital Spotmeter + Mod”

  1. On May 2, 2009 at 8:54 pm