How To Determine Which Diopter Magnification To Get

[S.Rolf]

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This really helped me how to read my latest eye exam Rx in determining which diopter correction lens to select.

 

http://www.allaboutvision.com/eyeglasses/eyeglass-prescription.htm

 

 

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[microview]

One thing that's important (and I quote from R4d Dot) "it should be noted that the Leica M's viewfinder is preset by default to -0.5 diopters. So anyone wearing glasses of 1 diopter strength would require a +1.5 diopters M system correction lens."

[Jeff S]

Simply take your camera (and glasses) to your local optician and put their free trial diopters in front of the VF. The one that provides the clearest focus and view is the right one.

 

No math needed.

 

Jeff

Edited September 3, 2017 by Jeff S

[jaapv]

One thing that's important (and I quote from R4d Dot) "it should be noted that the Leica M's viewfinder is preset by default to -0.5 diopters. So anyone wearing glasses of 1 diopter strength would require a +1.5 diopters M system correction lens."

Which is nonsense. The -0.5 diopter is there for a reason, i.e. to facilitate accommodation between the virtual 2 m of the rangefinder patch and the subject distance, whichever that may be. To "correct it away to 0" defeats the purpose.

 

Jeff has it 100% right. It either takes an accomplished optician to calculate the correct diopter, with all parameters considered, or simple trial-and-error.

[Guest NEIL-D-WILLIAMS]

Which is nonsense. The -0.5 diopter is there for a reason, i.e. to facilitate accommodation between the virtual 2 m of the rangefinder patch and the subject distance, whichever that may be. To "correct it away to 0" defeats the purpose.

 

Jeff has it 100% right. It either takes an accomplished optician to calculate the correct diopter, with all parameters considered, or simple trial-and-error.

A better way to do it is to take a Leica S or SL and without glasses if you plan to shoot your M without glasses look through the EVF and adjust the built in diopter until everything inside the viewfinder is sharp............look at the dial on the top and that is the diopter you need. I did this for my M6 and it worked perfectly +1 for me without glasses..............cool

 

Neil

[HugoSC]

Neil,

 

Was there a particular distance your were focusing, lens you were using or does it matter?

 

My main issue using my M is with landscape shots with trees in the distance. Very hard for me to distinguish when branches or foliage is lined up in the viewfinder and just setting the lens on infinity isn't the simple answer.

 

Thanks for your very useful tip.

 

Hugo

[Guest NEIL-D-WILLIAMS]

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Neil,

 

Was there a particular distance your were focusing, lens you were using or does it matter?

 

My main issue using my M is with landscape shots with trees in the distance. Very hard for me to distinguish when branches or foliage is lined up in the viewfinder and just setting the lens on infinity isn't the simple answer.

 

Thanks for your very useful tip.

 

Hugo

Hugo

I just make sure that the digital numbers in the viewfinder/EVF are sharp, that way when you look in the RF the patch will be sharp...........and from what I can remember that's the trick to using a rangfinder

Good luck, and please let me know how you get on?

 

Neil

[S.Rolf]

My Spherical  correction on my Rx for my sighting eye is +1.0.

I took into account the -.5 for the M10.

I ordered a +1.5 correction lens and it works perfectly.

 

There you go.  My2 cents.

[Jon Warwick]

Sorry to drag up an old post, but given I’m looking for the same answer (but still confused after reading the above), I thought it was suitable .....

..... the diopter on my SL2 shows -1.5 when everything is perfect through that viewfinder. As such, for an M, do I select a -1.0 diopter (to factor in the -0.5 that is “built in”), or do I ignore what’s built in and simply use a -1.5 diopter on the M??

My read of Leica’s web page seems to suggest the former (https://uk.leica-camera.com/Photography/Leica-M/Technical-Equipment/Viewfinder-Accessories/Correction-lenses-M), ...,, but then again I’ve read on this forum that some think to do the latter.

Is there a definitive answer?

Many thanks 

[Jnd28]

The bigger question is why doesn’t Leica have an adjustable eyepiece. It’s crazy that they do on the SL, the SL2 and the CL. But not on the M. It’s certainly not because of the M being a rangefinder. My Contax G2 has an adjustable eyepiece as does my Contax 645. Just saying!

[a.noctilux]

11 hours ago, Jon Warwick said:

Sorry to drag up an old post, but given I’m looking for the same answer (but still confused after reading the above), I thought it was suitable .....

..... the diopter on my SL2 shows -1.5 when everything is perfect through that viewfinder. As such, for an M, do I select a -1.0 diopter (to factor in the -0.5 that is “built in”), or do I ignore what’s built in and simply use a -1.5 diopter on the M??

My read of Leica’s web page seems to suggest the former (https://uk.leica-camera.com/Photography/Leica-M/Technical-Equipment/Viewfinder-Accessories/Correction-lenses-M), ...,, but then again I’ve read on this forum that some think to do the latter.

Is there a definitive answer?

Many thanks 

See post #3

the best way is going to Leica Dealer with your M and try different diopters,

or your nearest optician but that would be half solution.

[Antonio Russell]

On 9/4/2017 at 1:47 AM, jaapv said:

Which is nonsense. The -0.5 diopter is there for a reason, i.e. to facilitate accommodation between the virtual 2 m of the rangefinder patch and the subject distance, whichever that may be. To "correct it away to 0" defeats the purpose.

 

Jeff has it 100% right. It either takes an accomplished optician to calculate the correct diopter, with all parameters considered, or simple trial-and-error.

Hi, are you sure this is the case? Leica themselves say exactly the same:

"Please note that the Leica M-Viewfinder is preset by default to -0.5 diopters, so anyone wearing glasses of 1 diopter strength would require a +1.5 diopters correction lens."

 

https://uk.leica-camera.com/Photography/Leica-M/Technical-Equipment/Viewfinder-Accessories/Correction-lenses-M

[jaapv]

Yes I am sure. However the diopter strength compensation for 2 m varies with the strength of the diopter, so the calculation is more complicated that a simple addition. thus trial-and-error will yield the best results.

[Luke_Miller]

11 hours ago, Antonio Russell said:

Hi, are you sure this is the case? Leica themselves say exactly the same:

"Please note that the Leica M-Viewfinder is preset by default to -0.5 diopters, so anyone wearing glasses of 1 diopter strength would require a +1.5 diopters correction lens."

 

https://uk.leica-camera.com/Photography/Leica-M/Technical-Equipment/Viewfinder-Accessories/Correction-lenses-M

In my case my glasses are +2.5 diopters, but best correction occurs with either a +0.5 or +1.0 diopter correction lens on the viewfinder.  Perfect would be +.75 which would have to be custom made.  There does not seem to be any way to calculate the diopter needed from one's glasses prescription.

[AndrewDD]

For years I had a dioptre which was too strong, by going with the idea of adding 0.5 to the strength of my glasses. I always struggled a bit with focusing, but I assumed that was what it was. When my prescription changed recently (I now have 2 pairs, one for reading and a weaker pair for using a computer) it occurred to me that the focus patch is supposed to be about 2 metres away (I can't remember where I read this) so maybe my dioptre should match my computer glasses. I went into the Leica shop and tried a few - and ended up with a +1.0 (even though  my computer glasses are 1.5) and it has revolutionised my focusing.

There is one way to work out what dioptre you need - try it!

[codocee]

To try the different diopters in my city, I need to travel 180mi to Seattle, Wa.

The next nearest with diopters in stock is San Francisco which is 650mi.

Tough task for many.

Order all the different ones through Amazon and keep the keeper and return the rest.

[Helge]

vor 4 Stunden schrieb codocee:

To try the different diopters in my city, I need to travel 180mi to Seattle, Wa.

The next nearest with diopters in stock is San Francisco which is 650mi.

Tough task for many.

…

Definitely tough.

(I‘m just 40 miles away from Leitz-Park, Wetzlar)

[Jeff S]

12 hours ago, codocee said:

To try the different diopters in my city, I need to travel 180mi to Seattle, Wa.

The next nearest with diopters in stock is San Francisco which is 650mi.

Tough task for many.

Order all the different ones through Amazon and keep the keeper and return the rest.

Post #3.  
 

Jeff

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Hallo,

Look here: Leica M

[thrang]

My prescription reading glasses are +1.5.

I went to my optometrist this morning and tried various diopter lenses in front of the M11 viewfinder, and the clearest was the -1.0! I am quite confused!

[jaapv]

Quite possible and not surprising. Your reading glasses are for 30 cm, the diopter should ideally accommodate between 2 m and infinity (with the emphasis on 2 m). The markings in the viewfinder must be clear, not necessarily  the viewfinder in general.