Zoom display conversion to focal length?

[Chris Harding]

Hi Guys

As you know you can set your zoom display to either a bar or a value (0-99)

Now does anyone know if the 0-99 value is linear?? ie: if 00 = full wide (18mm on the stock lens) and 99 - full zoom (200mm on the stock lens) Then your actual range = 182 so the burning question I'm asking is when the display reads "50" ..is that actually 109mm or not (50% of the range = 91 + 18mm)

OR is it a proportion of the zoom magnification ie: zoom range = 11.11 so the display of 50 is assumed to be halfway so it's 5.55X which is actually 99.99mm

It would be nice to know what sort of range lens would suit the camera by using the stock zoom and being able to say that "I seem to be shooting wedding ceremonies around a display between 40 and 50 so I need a 3rd pary lens with around the 80 -100mm range.

Any one have any idea at all???

Chris

[Chris Harding]

Hi Guys

I had a bit of spare time this morning between jobs so I actually compared some 3rd party zooms to the stock lens and made a note of "comparable" zoom settings ...Firtly it's nowhere near linear at all but for those who are using the 18-200 zoom to determine what a prime FOV would be roughly like here are some very approximate settings done with my Nikon zooms using the lens barrel markings and the equivalent "Z" number when using the stock lens

24mm = "Z20"
35mm = "Z30"
50mm = "Z40"
85mm = "Z60"
105mm = "Z75"
135mm = "Z90"

Might be useful where you need to figure out what sort of prime lens you might find useful for something like a wedding ceremony where you are a set distance away.

Chris

[Michael Spanheimer]

Hey Chris...was searching the forum exactly for this.
Thanks for the research...

[Chris Harding]

Hi Michael

No problem ... it was mainly to try and figure out what manual lens I would need in Churches at weddings or at least what range zoom I needed. It was all fine to look at the LCD while filming the readings 30' away and notice that the zoom said it was at "23" ... I needed to be able to match it in millimetre focal length.

I try not to use the Power Zoom too much now but for stuff like sports it's brilliant!! but I just share one stock lens with two cameras ..all the rest of the lenses are manual but that covers me from 10mm to 200mm and mostly my mid ranges are all constant F2.8 which makes a huge difference in low light as the stock lens drops off very fast as you zoom.

Chris

[Michael Spanheimer]

HI
id love to have something like the sigma17-50 you use. Still not sure which connection type
i would chose. which adapter setup would be reasonable. Til now i have just an Minolta MD adapter.
If Amount would be the choice, which of those expensive sony adapters would be the right one?
Or is there already an Emount version out? Didnt see one so far.

[Chris Harding]

Hi Michael

I have the 17-50 and 28-75 Tamrons and the Sigma is the 17-35 F1.8

I also have a full Nikon stills outfit with two bodies flashes etc etc so it makes sense for me to get all my lenses in Nikon mount so I can use them on both still and video.

My adapters are Nikon to E-Mount ... the nicer (but pricey) one is a Novoflex (about 200 Euros!!) but I also have a cheap Chinese Photodiox dumb adapter that works much the same!! The only difference was the Chinese one cost me $30.00!! BUT I had to spend a long time with a ladie's emery board and wet 'n dry abrasive paper to get it to fit the camera and lenses. It wouldn't fit my camera at all as the 3 lugs on the adapter were simply too thick ..I filed them down carefully and it glides on now. The lens side was so tight I thought I might damage my lenses so again I had to file down and smooth the mount surface until the lenses also went on smoothly.

Really just buy whatever mount suits you...if you have (or are getting) a Canon still camera then get Canon mount lenses .... Just remember than you lose all your stabilisation, focus and exposure controls but I make sure I have decent camera support ..I ten run the cameras in auto and whatever aperture I set manually it adjusts the shutter and gain (like A mode on a DSLR) Focus is always manual but really easy!!

Chris