Distance measurement

[tashley]

We all know that DOF is a moveable feast. I, for example, have a new DOF calculator on my iPhone called TrueDoF-Pro which lets you set really anal-retentive parameters, such that at F5.8 on a Rodenstock 40 and IQ180, if you want to make a one metre wide print with 10LP/MM resolution, you know that you hyperfocal distance is 40 metres and that everything from 18m out will be good. Or, if you prefer, you can state a blur spot preference of 41 microns and know that your 'traditional' DOF is from 3.5 metres outwards if you focus at 7 metres. Etc etc. etc.

But I still want to focus really accurately sometimes, more accurately than focus mask can achieve and without all the difficult iterations of 'suck it and review on the LCD'.

SO I would like a rangefinder. But the good ones like the Leupold and the Leica Disto 5 seem to have restricted ranges of operation. As far as I can see, they both offer a minimum of 10 metres and a maximum that depends on target type but might be as little as 100metres or as much as 1000.

The HPF focus ring on my lens tops out at 52.7metres, which is a tiny nudge from infinity. But there's really quite small distance between that scale marking and 10.6 metres and then suddenly there are acres of space for everything under 10 metres - exactly the zone where laser finders seem to stop.

So, short of a tape measure (which would make me feel like an 1880's practitioner) can anyone suggest something as accurate as the HPF ring which works from let's say 1/2 metre and outwards?

I tried at Nikon 1000AS in the shop today and thought it seemed really nice and seems good value but again, it is a ten meter only option.

Thanks in advance!
Tim

 

[stephengilbert]

I don't know anyone who uses one, but carpenters' lasers have much closer ranges.

See, e.g., Bosch Dlr130K Laser Distance Measurer

 

[danlindberg]

My Disto 5 has a close range of 50 cm! Between half a metre and ten metres I use it without exception.
I have it mounted on any of my Alpa bodies with one calibrated offset for the traditional bodies and another for the FPS. I use the smallest ballhead on the market and is easy to manoeuvre and when on target I fix it rigid and take the reading. Works splendid!

Here on the SWA.

 

[cly]

the good ones like the Leupold and the Leica Disto 5 seem to have restricted ranges of operation. As far as I can see, they both offer a minimum of 10 metres and a maximum that depends on target type but might be as little as 100metres or as much as 1000.

The Leica D5 has a minimum distance of 5cm.

http://www.leica-geosystems.de/downloads123/cp/disto/DISTO D5/manuals/DistoD5_manual_us.pdf

(the technical data is in a table towards the end of the manual.)

Chris

 

[Guy Mancuso]

My Disto 5 has a close range of 50 cm! Between half a metre and ten metres I use it without exception.
I have it mounted on any of my Alpa bodies with one calibrated offset for the traditional bodies and another for the FPS. I use the smallest ballhead on the market and is easy to manoeuvre and when on target I fix it rigid and take the reading. Works splendid!

Here on the SWA.

Off Topic. What tripod head is that Dan

 

[tashley]

Thanks guys, I read a retailer website that said it was 10 metres, my bad. Jae Moon said in another thread, though, that he couldn't get it to work much beyond 45metres s it'll be fine for use with the Rodie 40 but not if I go longer eventually.

Guy, I think that's an Alpa micro leveller. Looks nice but weighs nly a touch less than a cube and has less movements.

 

[Shashin]

Guy, do you want to find out? Next you will ask about the price, and then...

It is a bottomless pit.

The head is from Linhof--3D Macro.

 

[Guy Mancuso]

LOL

Its worse than a bottomless pit. Thanks Ill check it out

 

[danlindberg]

Off Topic. What tripod head is that Dan

Indeed, as has already been answered. Linhof 3D Micro. Nice and sturdy but only for levelling, not for creative angles

The tiny tiny ballhead for the Disto is a Cullmann CB2, weighs nothing...

And yes, the Disto measures closer than my stated 50 cm!!!

 

[cly]

Jae Moon said in another thread, though, that he couldn't get it to work much beyond 45metres

It's a problem you don't run into if you do interior photography

But I tried it outside and while I can't remember exactly at which distance it stopped working - above 50m it became problematic in daylight. So I can confirm what Jae Moon said ...

Chris

 

[vjbelle]

I have used the Leica Disto for quite a while and up to distances of 200 feet it is flawless. At longer distances is does require a good target and it must be on a tripod or some type of level device for stability. I trust it completely and it has never failed me...... I just set the HPF ring to whatever the Disto indicates.

Victor

 

[thomas]

So, short of a tape measure (which would make me feel like an 1880's practitioner) can anyone suggest something as accurate as the HPF ring which works from let's say 1/2 metre and outwards?

I use a Leica Disto A3 (the model I use is not available anymore but there is certainly a successor). It starts at 5 centimeters and goes to around 100 meters. By the specs it is not preferable for use in bright sunlight at long distances... but I've only encountered an error message once - when I measured a white wall in full sunlight. I then pointed the Disto to measure the bottom right in front of the building and it worked fine ...

 

[gazwas]

When talking about shooting in the usual f11 region, are these types of laser measurement devises really needed with wide lenses like the RS40HR-W?

Has anyone ever tested being off by say a meter and using hyper focal against nailing the focus to the millimetre and compared the final sharpness between the two?

 

[thomas]

When talking about shooting in the usual f11 region, are these types of laser measurement devises really needed with wide lenses like the RS40HR-W?

Has anyone ever tested being off by say a meter and using hyper focal against nailing the focus to the millimetre and compared the final sharpness between the two?

it depends on how critical you are about focussing. Printed at native pixel size at 300 or 360ppi you maybe won't notice a really large difference. But once you start to uprez your captures to print big you'll see it (not as pronounced as at 100% magnification on a monitor screen... but the impression is pretty similar).
I'd say you clearly see whether the shot was focussed at 25 or 30 meters distance even at f11 (talking about the Digitar 43XL... which should be similar to the 40HR). The reason is that the micro contrast in the plane of focus is extremely high (it get's evened out a bit once you hit diffraction). And since 25 and 30 meters is pretty close to the infinity setting on the lens you just have to softly touch the focus ring to make this adjustment. I am exaggerating a bit... but yes, these laser distos are really, really helpful.

 

[AreBee]

Guy,

...Ill check it out

I previously investigated the head. My understanding is that:

a) The Linhof gear pitch is finer and hence the head offers greater control than the Arca Cube, albeit the range of rotation is not as large as the latter (hence the reason Linhof refers to it as a "levelling head"
b) The two geared axes work perpendicular to the Cube's axes. In other words, turning the side axle rolls the head left/right, whereas with the Cube it pitches forward/back - Dan, please correct me if I am mistaken

Food for thought.

 

[photomgraphy]

We all know that DOF is a moveable feast. I, for example, have a new DOF calculator on my iPhone called TrueDoF-Pro which lets you set really anal-retentive parameters, such that at F5.8 on a Rodenstock 40 and IQ180, if you want to make a one metre wide print with 10LP/MM resolution, you know that you hyperfocal distance is 40 metres and that everything from 18m out will be good. Or, if you prefer, you can state a blur spot preference of 41 microns and know that your 'traditional' DOF is from 3.5 metres outwards if you focus at 7 metres. Etc etc. etc.

great app tashley - thanks!

 

[tashley]

great app tashley - thanks!

It's cool isn't it? I love the way it lets you specify print size and resolution, though the resulting DOF for a metre wide print is pretty much that there's NO DOF!

The only irritating thing is that it doesn't actually telly uo the exact hyperfocal distance, just shows it on a scale. Otherwise it is the best I have yet found, though there is one more version above it that might be even better.

 

[tashley]

And thanks for the info on the disto everyone!

 

[photomgraphy]

It's cool isn't it? I love the way it lets you specify print size and resolution, though the resulting DOF for a metre wide print is pretty much that there's NO DOF!

The only irritating thing is that it doesn't actually telly uo the exact hyperfocal distance, just shows it on a scale. Otherwise it is the best I have yet found, though there is one more version above it that might be even better.

the blur spot diameter = circle of confusion, right?
so i set it to 40microns (39mpx hasselblad back)

lp/mm for print resolution? how does this convert into ppi?
are 10 lp/mm equal to 508ppi? if i assume, that one line is equal to one pixel...

let's say my usual print size is 17x24 at 300ppi - what would i have to dial in to get that?

i'm a littlebit confused by that.

 

[torger]

I've used the Disto and some other laser distance meters. You really need the Disto D5 for outdoor work. You need the display to be able to direct the laser beam (you won't see the spot on longer distances when bright outside), and you need the quality of the Disto for it being able to pick up the reflection. Older/cheaper distance meters are not as good at taking reflections off tree trunks etc in daylight (they only work well indoors and/or flat surfaces like walls). Still there is some limitations with the Disto, getting a measurement off a bush can be difficult for example.

I thought about getting a Disto D5 for my Linhof Techno system but I ended up with a vintage Leitz Fokos rangefinder, very small optical unit, no batteries. Not at all as accurate as a laser finder of course, but fits very well the more relaxed focusing style used with a view camera (which I find adequate, I'm not really missing HPF, especially since I use tele and tilt a lot).

For an Alpa with HPF ring high focusing precision is part of the concept and then I'd see the Disto D5 as an almost mandatory accessory.