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would a cheap prime lens improve photogrammetry on 24mp cam?

gnoop
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gnoop sublime tool
I have sony a6000 24 mpix APC-s camera with default  kit zoom lens pz14-50.  Photogrammetry have always been so-so an softy with this camera.      Chat GPT tells me it's a soft lens and uses only 60% of matrix resolution. Which surprises me  because I always though its sensor resolution mostly .  
  Chat tells  me  all those boke , corner sharpness ,color accuracy are irrelevant for the photogrammetry and  suggests to buy a cheap prime (fixed manual lens)  less then  $100  and it will provide sharper details in the center  which is only thing that really matter. 

I wonder  does anyone tried such lenses ?  like this https://radojuva.com/en/2021/03/7artisans-1-8-25mm-hd-mc/
for example . would it really be better than the kit lens?

Does anyone  ever dealt with such a cheap lens. Are they really doing better geometry?     I once had much more expensive prime  and it worked nicely, , but perhaps chatGPT  is right and a cheap one is enough? 


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  • Sempoo
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    Sempoo triangle
    Kit lenses are almost always inferior. Most important is lens MTF, it is best at apertures around f/8 [lower for wide angle lenses and higher for tele].
  • gnoop
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    gnoop sublime tool
    Thanks.Sempoo it hard to find  mtf values  for cheap lenses. looks like nobody cares to measure.  I took my info from imaging-resource.com before  but after it had been sold  it all gone from there.   There are a few cheap manual lenses around currently .  like TTArtisan 23 mm  https://www.5050travelog.com/camera-and-lens-reviews/ttartisan-23mm-f14-review
    but i couldn't find any objective resolution  value  MFT or old fashion lines per mm.
    General perception those cheap lenses do nice crispy details in the center and blurry corners but I think it's not so important probably for actual photogrammetry.       
    So I wonder if anyone did have an experience?    Those cheap  lenses are usually small and light weighted  vs  pro ones.  I am lazy to wear a big bulky thing in my scanning trips 
  • Sempoo
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    Sempoo triangle
    Again, hair splitting.
    Approach this problem in the way that you make photographs in manual mode, ISO100, f/8, 1/125s or more [but not less due to camera shake] - this will be enough. Or you can even use tripod or even monopod.
    Did you googled 'sharpest lenses'?
  • gnoop
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    gnoop sublime tool
    Yes I googled sharpest lenses  . Those would be Sigma ones for sony e-mount  and they are not that much expensive too.  I just wonder  if they do any difference vs this  TTArtisan 23 mm  or even kit lens  when set  at f/8  or f/5.6    I don't like too soft mesh details  I get from a6000  with those apertures  and it's definitely not a tripod /mono pod issue  since I got excellent mesh details from 19 mpix  foveon matrix Quatro dp2  camera just  of hands with 1/250 sec .     

        I think most of  expensive  lens value  goes to maintain good resolution at f/1.4    . in a word totally redundant  thing for photogrammetry . its where all those bulky  extra lenses and expensive glass parts go.     Gemini  and chat GPT  say   "sharpest lenses"  would still matter.    I just wonder if it's true around f/8   or 24mpix Bayer would never show anything close to Foven matrix anyway?   





  • pior
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    pior grand marshal polycounter
    Step 1 : do some research, meaning reading manufacturer info and user reviews.

    Step 2 : do the thing you want to do with the resources you have at your disposal.

    Step 3 : if you aren't satisfied with the results, post them online for people to have a look and give you advice based on their own experience, or bring them to your local photo store for professional advice.

    https://xyproblem.info/
  • gnoop
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    gnoop sublime tool
    Thanks pior   it's a good plan indeed.  Just not very much related  to the specific  question I am asking :  if anyone have experience  with a cheap, all manual prime lenses  and whether they give an essential  resolution boost in resulting mesh on 24mp cameras .      Simple like that . No XY something.    

    I just hoped folks here might  since cheap primes are usually small and very travel friendly  and artists in my experience usually like small cameras with small lenses since photography equipment is not their main occupational expenses.      



  • pior
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    pior grand marshal polycounter
    IMHO you're still skipping on the most basic step of troubleshooting which is to provide a practical case of what you're having an issue with, for people to have a look.

    And as the person having the issue, there's no way for you to know that your envisioned solution (in this case, buying some other lens) is actually worth spending time and money on. There could by many other factors, but by framing the issue on only one of them you might be robbing yourself of a solution.
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