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On 8/30/2019 at 4:31 AM, heart0less said:

 

Honestly, I'm not entirely sure what my personal plan will be just yet, but the double whammy of this great breakdown video on the Contax Zeiss lenses and Panasonic's full reveal of the S1H are making me consider a transition over to that sort of camera-lens combo. Much too expensive to try and save for a Kinefinity Mavo LF for now.

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Got myself some new glass for Christmas. I do prefer native lenses but the Sigma Speedbooster combo works really well! Screengrabs from GH5 + Speedbooxter XL + Sigma 35/1.4 + Black Pro Mist 1/4. 

Just got a Voigtlander 40mm 1.2. Haven't had a chance to test in video yet. But DAMN

A few stills from a shoot last night all on the Pocket 4K XL and CZ 35mm 2.8. 

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1 hour ago, Vintage Jimothy said:

Honestly, I'm not entirely sure what my personal plan will be just yet, but the double whammy of this great breakdown video on the Contax Zeiss lenses and Panasonic's full reveal of the S1H are making me consider a transition over to that sort of camera-lens combo. Much too expensive to try and save for a Kinefinity Mavo LF for now.

The S1H does seem like a hell of a good package. $4000 is a lot but not relative to what it offers


I think the S1 is a heck of a good deal at under $2000 used, I'll most likely pick one up asap. Even without VLOG, Cinema 5D measured HLG a whole stop better than my XT3's Flog, which already is pretty good. I'll just throw on my vintage nikon lenses and call it a day. 

What would be really cool is if someone makes a focal reducer and I can use medium format lenses. 

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5 minutes ago, thebrothersthre3 said:

The S1H does seem like a hell of a good package. $4000 is a lot but not relative to what it offers


I think the S1 is a heck of a good deal at under $2000 used, I'll most likely pick one up asap. Even without VLOG, Cinema 5D measured HLG a whole stop better than my XT3's Flog, which already is pretty good. I'll just throw on my vintage nikon lenses and call it a day. 

What would be really cool is if someone makes a focal reducer and I can use medium format lenses. 

why don't you compare with xt3 hlg which is better than log ?

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It’s official: Veydra LLC has gone out of business

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~ via https://www.mirrorlessrumors.com/its-official-veydra-llc-has-gone-out-of-business/#disqus_thread

Between the stolen units... the Meike clones now popping up and apparent internal issues within the company this was kinda foreshadowed. Sad though.

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Hey guys, just a quick question.

So, I thought, when using the same lens, the same focal length, the same distance to subject and the same f-stop, the DOF will be exactly the same regardless of which camera or sensor size you mount the lens on. It's just the FOV that changes with different sensors, not the charataristics of the lens. Correct?

Well, this DOF calculator shows otherwise.

 

1.thumb.png.c6373ef64cca6e9f18d45a582fbcedbb.png2.thumb.png.62053f204bc66c4c388c275b9053f2c2.png

 

As you can see, I choose the same lens (70mm f2.8) on both sensors (Full frame and MFT), same distance to subject, same f-stop. According the DOF calculator the DOF is shallower on the MFT (0.43m) than on FF (0.86m). I expected the same DOF (but of course different FOV).

Is this correct?

 

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56 minutes ago, Stab said:

Hey guys, just a quick question.

So, I thought, when using the same lens, the same focal length, the same distance to subject and the same f-stop, the DOF will be exactly the same regardless of which camera or sensor size you mount the lens on. It's just the FOV that changes with different sensors, not the charataristics of the lens. Correct?

Well, this DOF calculator shows otherwise.

 

1.thumb.png.c6373ef64cca6e9f18d45a582fbcedbb.png2.thumb.png.62053f204bc66c4c388c275b9053f2c2.png

 

As you can see, I choose the same lens (70mm f2.8) on both sensors (Full frame and MFT), same distance to subject, same f-stop. According the DOF calculator the DOF is shallower on the MFT (0.43m) than on FF (0.86m). I expected the same DOF (but of course different FOV).

Is this correct?

 

I think you are correct - it's the same lens, how could the depth of field change ? They may be taking into account circle of confusion and resolution of the cameras, do they say how they calculate the limits for near and far limits ? It could also be that they are working back from the 2x crop and that is a problem with their methodology or code. I could see this error coming in if they calculate the depth of field based on it being a 140mm equivalent and working back, but that is wrong. 

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40 minutes ago, thephoenix said:

problem is distance to subject.

if you have a crop then your field of view changes. to have the exact same framing you need to move and then you change the dof

But OP didn't change the subject distance between the cameras, so..

 

@Stab, you are 100% correct. DOF should remain the same.

 

Some great article about the issue:

https://fstoppers.com/education/understanding-how-sensor-size-affects-depth-field-312599

 

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26 minutes ago, heart0less said:

But OP didn't change the subject distance between the cameras, so..

 

@Stab, you are 100% correct. DOF should remain the same.

 

Some great article about the issue:

https://fstoppers.com/education/understanding-how-sensor-size-affects-depth-field-312599

 

Right, I thought so.

But, that means the DOF calculator is wrong??

There is another one online, this one, at it shows the same values. Are they both wrong?

https://www.dofmaster.com/dofjs.html

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4 minutes ago, thephoenix said:

That's my point. framing will not be the same because of crop factor 

You need to compare the same dreaming 

No you don't. I'm not trying to compare the framing or make the same shot. 

I put the same lens on 2 different camera's on the DOF calculator at the same distance. And it should show that the DOF is the same. At least, that's what I thought. It doesn't matter that the framing isn't the same. A 70mm is a 70mm. It doesnt matter if you mount it on a full frame camera or on a banana.

A crop sensor is basically the same as cropping in post and then blowing the image up to the same size as it would have been on the full frame camera. It doesn't change any other stuff, besides that you have a narrower FOV. That alone doesn't change the DOF. The DOF will only change once you start zooming in / out or moving. Which the DOF calculator doesnt take into account and is not what I'm asking here.

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27 minutes ago, Stab said:

There is another one online, this one, at it shows the same values. Are they both wrong?

https://www.dofmaster.com/dofjs.html

Funny thing is: the DOF calculator I use (https://dofsimulator.net/en/), shows it, too..

 

What's even more strange, the hyperfocal distance is different than what you get at PhotoPills.

image.thumb.png.9fb2d56199b32b789245d6d3bfbad6be.png

 

image.thumb.png.5bef70c1a7d2f86889c7f21dd0dc5176.png

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1 hour ago, thephoenix said:

The 70mm for m43 Is like 140mm for ff

Check with a 35mm.

and 2.8 ff becomes 5.6 for m43

If i use mine It goes like This

 First Is ff 70mm 2.8

second is m43 35mm 1.4

  

 

 

 

 

Screenshot_20190901-234519_DOF simulator.jpg

Screenshot_20190901-234559_DOF simulator.jpg

Yes, that makes sense. With a crop factor of 2x you multiply the focal length and the f-stop by 2x to get a similar FOV and DOF.

Got it.

But, on the DOF calculator that I used, I didn't want to match any framings. I just put the same lens on 2 different bodies. And the MFT sensor had a shallower DOF than the Full Frame sensor. If that is correct, then why is that?

Same distance to subject, same lens, same everything.

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The calculators are correct.

The part that is giving you guys a headache is how you measure DoF.  Something doesn't just go from being in focus and then you move it a millionth of an inch and it's now blurry.  The way that these calculators measure DoF is called the Circle of Confusion, which is how blurry something can get before you can tell it's blurry.  As the two different sensors you've chosen are physically different sizes but have roughly the same resolution, the smaller sensor needs something to be better in-focus before it is detectably blurry.

https://en.wikipedia.org/wiki/Circle_of_confusion 

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For describing the largest blur spot that is indistinguishable from a point. A lens can precisely focus objects at only one distance; objects at other distances are defocused. Defocused object points are imaged as blur spots rather than points; the greater the distance an object is from the plane of focus, the greater the size of the blur spot. Such a blur spot has the same shape as the lens aperture, but for simplicity, is usually treated as if it were circular. In practice, objects at considerably different distances from the camera can still appear sharp (Ray 2000, 50); the range of object distances over which objects appear sharp is the depth of field (“DoF”). The common criterion for “acceptable sharpness” in the final image (e.g., print, projection screen, or electronic display) is that the blur spot be indistinguishable from a point.

ie, if a tiny detail is being projected onto the sensor and it's one quarter of a pixel wide, then you move the object forwards a bit and now that object is slightly out-of-focus and it's now half-a-pixel-wide it will still appear to be perfectly sharp to that sensor, despite the fact that if you had infinite sensor resolution the DoF of any lens would be zero.

Here's the circles of confusion from dofmaster:  https://www.dofmaster.com/digital_coc.html

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