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Understanding sharpness for an admitted pixel-peeper

panda81

New member
So, I admit I'm a pixel-peeper. I constantly blow up my photos to 100% to examine my lens' sharpness. With everything I've read about the M9 and the 50mm Summilux ASPH (as one review stated, the sharpest 50mm lens ever made), I was expecting to see absolutely remarkably sharp photos at 100%. Unfortunately, at first, I found out my M9 had some focusing issues, so it made a trip to Leica in NJ and came back fully inspected and repaired. My 50mm Summilux ASPH also made a trip to DAG, who verified that it was focusing properly.

So, after my M9 came back, I was expecting to be blown away when viewing photos at 100% (most taken with aperture wide open). However, I really wasn't. It was sharp, but honestly I feel like I've seen better. My basis for comparison are viewing photos taken by various lenses coupled with my Nikon D700. I have been WOW'ed with how ridiculously sharp some of my photos are with certain lenses taken wide open, viewed at 100% (for example, Zeiss ZF series, Nikon 200 f2 VR, even Sigma 50/1.4). When I viewed Leica photos at perhaps 25% or 50%, I have to admit some look pretty great. However, I guess I was hung up on 100% because sometimes even out of focus photos can look "sharp" when viewed at lower magnifications.

Then, something suddenly dawned on me. The Leica sensor is 18mp, but the D700 sensor is 12mp.

I guess my question is, is the difference in resolution the reason why the Leica photos look "softer" than the D700? Is it an unfair comparison to examine a 12mp photo at 100% with a 18mp photo at 100%?

Another absolutely viable reason may be that I'm still not used to shooting with rangefinders. Especially when shooting wide open, I can see why the photo might be a bit out of focus when I use the rangefinder patch in the middle, then recompose by moving slightly.

Anyway, I would really appreciate hearing everyone's ideas and experiences in this matter. And I know, pixel-peeping isn't always the best thing to do, but just humor me :D
 

LCT

Member
Interesting that you compare the M9 to the D700 which needs more sharpening in PP. Did you have the lens and the body adjusted altogether? Did you use the same raw converter for both cameras?
 

sven

New member
I have a D700 and an M8 not M9. But since they have the same sensor units or pixel size, there should not be much of a differnece. The D700 is one of the best autofocus camera cameras available in the market and it's viewfinder is again top notch for manual focussing. Combine that with current computer aided/designed lenses whether Nikon or Sigma, you are going to get sharp images. This not only holds true for D700 but for most current digital cameras including panasonic gf1 and Olympus e-p2. So I do not think anyone is going to be blown away by difference in sharpness.

Comparing pictures from M8 and 50mm lux to the D700 my impressions are they are equally sharp. I do not see any difference in sharpness. The difference that is obvious to me is that the Lux has enormous micro contrast throughout the aperture range and looks different than say Nikon,Zeiss or Sigma 50mm lens (I own all 3 lenses). Nikon and Zeiss have loads of macro contrast but I do not see why that should make images appear sharper at 100%, it should be the other way round if this influences sharpness at all.

My opinion is that you are either not focussing the M9 to the optimum or you must have motion related softness. This might be coupled with the fact that your expectations were very high in that you expected to be blown away by sharpness. Try focusing on something that is easy for rangefinder focus like objects with straight lines like the edge of door or a leaf against a different color background. Make sure shutter speed is at least 1/100. If it is still soft (do not expect to be wowed, it is going to be similar to D700 in sharpness), then both send the camera and lens together for calibrations as LCT suggested.

Hope this helps,

Sven
 

glenerrolrd

Workshop Member
This is a complex question because a half dozen factors come together to create the appearance of a sharp image. But you want to determine if your M9/50lux is delivering the desired IQ and if it is material better than the D700 and the best glass.

Calibration...this is very difficult as the M9 and the 50 summilux is IMHO the absolute toughest calibartion challenge(after the 135apo). Create a target that you can shoot at 2M and another at 10M ....keep the target at the same height as the camera lens and make sure its at a 45degree angle . Aim at the middle . Take a series of 5 images refocusing each time. Inspect on your computer not on the screen. You should easily see the plane of focus and DOF ..plus how many times did you nail the focus.
 

glenerrolrd

Workshop Member
Subject to Camera Distance...even though the 50asph has floating elements its not optimized for distances inside 2M ..its better but its a fast all purpose lens...with the emphasis on fast. Often lens tests are done with subjects in close ..e.g. a head shot. With a 50mm thats close range. It will not match the Zeiss ZF Macro lenses inside 2M. This can throw off your evaluation.
 

docmoore

Subscriber and Workshop Member
This is a complex question because a half dozen factors come together to create the appearance of a sharp image. But you want to determine if your M9/50lux is delivering the desired IQ and if it is material better than the D700 and the best glass.
Often overlooked in the quest for sharpness is subject matter....which is why Bruce Fraser and the group that programmed Photokit Sharpener have a system that sharpens based on subject and output characteristics.

In the lenses mentioned optical sharpness should be a wash...really, do you expect to find a sharper lens than Nikon 200 F2?

Microcontrast color and dynamic range are elements that differentiate the CCD in M series digital bodies....not pixel sharpness. I think that if a pixel is in the focal plane it will be sharp regardless of which sensor you use.

How you sharpen the capture is critical and you should spend as much time reading theory concerning this as you do playing with your lenses....

Recommended: Real World Image Sharpening with Adobe Photoshop, Camera Raw, and Lightroom, 2nd Edition

http://www.adobepress.com/bookstore/product.asp?isbn=0321637550


Bob
 

glenerrolrd

Workshop Member
Aperture ......Fast lenses all suffer somewhat when shot wide open. Yes the summilux may have one of the alltime best performances wide open..but its better stopped down to f2.8 . Plus when the subject is closer to the camera f2.8 can be really shallow. Test it with some portraits ...whats your favorite aperture when you look at the DOF applied to a subject.

Let me provide an example....I shot a parrot head and posted the image in the Nikon section of the forum. It was on a D3x with a 100/2 ZF macro .. I have about an 6 inch section of the parrot maybe a little more . The DOF is just about the width of the parrots eye at F5.6. I could get the eye "sharp" about 5 out of 6 times but in the middle of the DOF once. My eyes are quite good never wear glasses. Critical sharpness
is hard to achieve up close.


Those are just three factors that you might consider but I have had the same concerns when I was calibrating my asph lenses. I have used both Leica and DAG and unfortunately you have to do the tests yourself and document the issues. Its just too easy to get close but still not good enough.
 

docmoore

Subscriber and Workshop Member
Then, something suddenly dawned on me. The Leica sensor is 18mp, but the D700 sensor is 12mp.

I guess my question is, is the difference in resolution the reason why the Leica photos look "softer" than the D700? Is it an unfair comparison to examine a 12mp photo at 100% with a 18mp photo at 100%?
While we tend to do this there is an element of magnification that may affect our perception of sharpness...at 18mp the 100% view will tend to be magnified and as such lines that define our visual field with regards to edge effects and perceived sharpness may be less noticeable.


Ever notice how a macro of a rose petal may be dead sharp but seems less so than the intricate detail of the pistil/stamen of another structure...do to edges that enhance our sense of sharpness.

Bob
 

glenerrolrd

Workshop Member
I think that if a pixel is in the focal plane it will be sharp regardless of which sensor you use.

Bob[/QUOTE]

Nothing is ever this simple when discussing IQ?

(1) CCD sensors generally have weak or limited AA filters thereby rendering sharper images at the expense of moire .

(2) Placing the exact plane of focus in an image using a digital M ..wide open (at 1.4) and with a subject inside 15ft is "difficult" if the subject is still.

(3) Larger sensors require less magnification to produce the same output rendering.

(4)Lower ISO s(and avoiding noise) and getting the exposure right impact sharpness robbing noise.

But my experience with the M series is that being able to truly "nail focus" is most important. You have to start with a sharp capture before the raw conversion and post processing can kick in.

Agree 100% with Bob s other points about sharpening and factors other than sharpness(DR,ColorSat,MicroContrast) that create IQ .
 

glenerrolrd

Workshop Member
Which is why I tend to get more keepers with my Oly E-P1 and live focus than I did with my M8.

Bob
As always it depends on what you want to shoot. Live view would seem hard to use on anything that moves.

But certainly working with an M requires both decent eyesight and a greater commitment to "practice" . Plus the challenge of a keeping a rangefinder system tuned.

My guess for the OP is that (1) you are not nailing focus (for whatever reason) and (2) you are shooting in close wide open with a speed lens.
 

panda81

New member
A lot of great points so far, I really enjoy reading everyone's thoughts and ideas. Thanks everyone!! I've only been able to skim through it so far, so apologies for not addressing every question and point. But, I just wanted to say that I'm glad no one misunderstood my post as "Nikon is better than Leica" because that's really not what I was trying to say :) Rather, I was approaching this issue because I'm new to rangefinders and I know I have much to learn, all the way from shooting technique to post-processing. So, everyone's suggestions are all very valid to me.

One thing I did want to respond to is that I didn't realize shooting the Summilux isn't optimized for shooting under 2m. Most of my shots are actually even under 1.5m, so that may be part of the reason right there. Coupled with possibly improper technique (hey, I'm used to bigger DSLRS, not small Leica boxes :) ), then we really might be onto something...
 
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