APS sensors vs. m4/3?

[stillshunter]

I gave my due to the EP3!

Fair call Armando, but I put the 'pop' entirely down to the PL25 (and PL45) - they both work just as well on the GF1 as they did on the EP3.

 

[Pelao]

I have no real logical explanation why I use both m4/3 and APS-C.

I go from cameras with sensors that range from small to m4/3 to APS-C to full frame. I probably choose which one to pick up most often based on guilt of not having used a particular camera in a while!!!

With the advent of smaller cameras sporting APS-C sensors like the NEX, GXR and most recently the X100, I'm getting more and more enamored with what I perceive to be superior image quality in terms of dynamic range and sometimes noise control at high ISO.

For whatever reasons, to my eyes anyway, the APS-C cameras seem to give me images with the "it" that I find lacking on m4/3. Out of all the m4/3 cameras that I've owned/used (EP2/3, EPM1, GF1/2/3, G3, GH2), the EP3's JPG photos was the closest to giving me the same "it" feel from images that I get on the X100 and the K-5. I returned the EP3 because of the rattlesnaking when using the PL25. In any event, the "it" or "pop" or "look" or whatever is it that we can call "it" is purely subjective.

In my ideal world, there would be a full frame camera roughly the same size as the X100 with interchangeable and auto focus lenses no larger than M lenses, but with the auto focusing abilities of the Nikon 1. And all of that for $399. Not too much to ask for right?

+1
Thanks - saved me a bunch of typing.

 

[Armanius]

+1
Thanks - saved me a bunch of typing.

LOL!! Great minds think alike!

 

[Naveed Akhtar]

more into sensor sizes ... i promissed myself not to speak more on this .. but lets break it for a lesser sin .. :tongue:
a prime lens (of one focal length, obviously ) will give you same DOF, sharpness, CA etc no matter what sensor size you put it on, at a given apperture. Actually vig and ca will be lower on small sensor bodies as it will be a crop at the middle, where the effect of such things is less.

actually the only difference will be the crop factor .. nothing more ...

e.g. my nikon 50mm f/1.4 lens at f/1.4 will give the same CoC or Dof no matter I mount it on FF, APS-C or with an adaptor on Pen E-P1. Its tested and proven! The crop factor however will keep it 50mm on ff, make it 75mm (FF equivalent FOV not focal length on APSC) and 100mm (equivalent fov on m4/3)...

 

[flash]

more into sensor sizes ... i promissed myself not to speak more on this .. but lets break it for a lesser sin .. :tongue:
a prime lens (of one focal length, obviously ) will give you same DOF, sharpness, CA etc no matter what sensor size you put it on, at a given apperture. Actually vig and ca will be lower on small sensor bodies as it will be a crop at the middle, where the effect of such things is less.

actually the only difference will be the crop factor .. nothing more ... ok ...

e.g. my nikon 50mm f/1.4 lens at f/1.4 will give the same CoC or Dof no matter I mount it on FF, APS-C or with an adaptor on Pen E-P1. Its tested and proven! The crop factor however will keep it 50mm on ff, make it 75mm (FF equivalent FOV not focal length) and 100mm (equivalent fov on m4/3)...

Tested and proven by whom? I've seen this a few times before but have yet to see a definitive test. My tests and personal experience seem to show otherwise.

The CoC (circle of confusion) is not a lens characteristic. It's a theoretical point (actually the point at which a circle becomes to small to be seen as a circle and at which it looks like a solid point) based on a given print size (usually, but not always 5x7 inches) and viewed at a given difference. The CoC has nothing to do with the lens used at all. Because it takes less enlargement for the COC to be visible on the print from a larger sensor the CoC becomes larger as the sensor becomes larger.

There is an issue that cameras with a lower pixel density may not be able to even reproduce a circle of confusion (requires 9 pixels), however fast 35mm film also reaches a limitation of its ability to produce a CoC.

Both my DOF charts dispute this "fact". At 1m a 50mm lens at 1.4 on a 35mm camera has a DOF of 31.9mm. At 1m a 50mm lens at 1.4 on a 4/3 sensor has a DOF of 16mm. Almost exactly half, which coincides with both the difference in sensor diagonal and the difference in the CoC of the different sensors (0.015 for 4/3 and 0.03 for 35mm). Even the "equivalent" 25mm lens at 1m and f1.4 has a DOF of 65.5mm. The achieve a similar framing for a 4/3 camera vs a 35mm camera requires either a wider lens or a longer shooting distance. Both of these increase DOF. Shooting a fixed focal length at a fixed aperture and a fixed distance to the subject, with no regard for framing (because you will crop the subject) will actually lead to a shallower DOF because the 4/3 image will need more enlargement to reach the same print size.

But shooting with no regard for framing is impractical in real world usage. If you want shallower DOF you're going to be better off choosing a larger sensor. If you want more DOF then choose a smaller one.

Gordon

 

[Country Parson]

But shooting with no regard for framing is impractical in real world usage. If you want shallower DOF you're going to be better off choosing a larger sensor. If you want more DOF then choose a smaller one.

Gordon

Well said, Gordon. It is all about the physics of optics, a subject most photographers neither understand nor care for. But your summary line (quoted here) is what all need to know.

 

[woof]

I own a K-5. I am new to MFT. I just finished evaluating whether I can convert completely.

The answer was an emphatic "yes..." ... for some things. Sigh. That's really a "no."

I shoot my kids a lot and sports is a part of that. The MFT I chose does not do that well (are there any that do? I ask this innocently and without irony). I also like the flexibility that shallower DOF can offer. Also, I have found a number of situations where the MFT I've chosen seems to handle too much light in the frame in a very unattractive way. I will not link this to dynamic range, because it feels like there is more going on and that the issue is more "mechanical" than measurement. It's the WAY the light is handled or perhaps NOT handled. Finally, the K-5 low light capabilities are key in a number of situations for me.

All of that said, image quality over size and weight, I will probably usually ask the question as to whether MFT can handle the task at hand and if not will revert to the K-5.

As a practical matter I have not touched the K-5 since about October. I've been busy, and I have been evaluating, so that is a part of it, but... still...

woof!

 

[Armanius]

Both my DOF charts dispute this "fact". At 1m a 50mm lens at 1.4 on a 35mm camera has a DOF of 31.9mm. At 1m a 50mm lens at 1.4 on a 4/3 sensor has a DOF of 16mm.

Should it be the other way around?

Circle of Confusion reminded me of "circle of trust" from the movie Meet the Parents.

 

[BBW]

"Circle of trust" - now that's something I can get my head around.

 

[Brian]

I do not get wrapped up in "stuff".

Know the equipment that you have, and use it to fit the situation. Or use it just when you feel like using it, and do your best with it.

If you want to read some good books on the subject, "Lenses in Photography", Rudolf Kingslake, is a good one.

 

[Steve Noel]

I have used various 4/3 (E-1, E-500, E-520, E-420) cameras for a few years, and found that my biggest complaints were; sorry view finders (small), and noise in low and/or mixed light without flash. I moved to m43 for reduced size, then added old man hand shake to the problem. I learned how to work around the noise, some what. I learned to compensate for hand shake, by using "props". Really wanted a better view finder.

Bought the Pentax K20. Noise is much better. View finder is better. Anti-shake combined with the camera weight has greatly helped old man hand shake. Over all my Picture quality has been a bit more consistent.

BUT. The bulk and weight make it harder to just grab-n-go. So I have listed it here for sale. IF it sells then what? I don't know. Still listening and looking around. Probably back to m43. I do have a good selection of legacy glass and adapters. Though I find that I mostly use one lens.

I cannot afford more than one good camera at a time. So if the K20 sells, I am going to greatly miss it. I consider the K20 to be the best digital camera I have ever owned. Not perfect, but very good.

 

[Lili]

I have had 2 APS-C's both Pentax DSLR's. I liked them and their IQ but the feature set and slightly smaller form factor of the 4/3 DSLR's won out. Now my m4/3 have pretty much supplanted my DLSR's altogether.

 

[Duane Pandorf]

I'm going to second what Cristian said earlier now that I have the GXR A12 mount. The lenses I will invest in will continue to work for a long time. The electronic lens will become obsolete as new technology comes along. I too can only afford one camera at this time but I want the flexibility a common lens mount so that investment is not lost. I can understand others needing or wanting an auto focus system but right now I'm excited about this new direction I've ventures upon.

 

[Biro]

I have been using both APS-C and micro four thirds for a few years now. I have two Pentax DSLRs (K-5 and K200D) and nine Pentax lenses to go with them. And, of course, I have the micro four-thirds kit and compacts in my signature below.

It's true: You do get a bit more dynamic range and a bit less noise (especially at higher ISOs) with APS-C. Nonetheless, I find micro four thirds to be the best compromise between cost, size, weight and image quality - at least for me - compared to any other system. Some systems may be better in any one of those categories, but I believe micro four thirds offers the best balance between them all. No, I don't waste my time pixel-peeping and I don't print larger than 13x11.

Plus there's this: None of my micro four-thirds lenses cost more than $500. In fact, only one of them cost that much - the Lumix 100-300. All the others were in the $300-$350 range. You'll notice I have none of the $800-$900 micro four-thirds lenses. And that will probably remain the case until I decide to let my Pentax kit go and focus (pun intended) on mirrorless only.

 

[flash]

Should it be the other way around?

It seems like it should but no, the figures are correct, according to both the calculators I use. The more enlargement needed the less apparent DOF you get if the print size is the same. 4/3 has more apparent DOF because you need to either move significantly further away or choose a much wider optic to get the same framing.

It reminds me of when I was learning exposure and couldn't get my head around why all the freakin' numbers were backwards...

Gordon

 

[Naveed Akhtar]

Both my DOF charts dispute this "fact". At 1m a 50mm lens at 1.4 on a 35mm camera has a DOF of 31.9mm. At 1m a 50mm lens at 1.4 on a 4/3 sensor has a DOF of 16mm. Almost exactly half, which coincides with both the difference in sensor diagonal and the difference in the CoC of the different sensors (0.015 for 4/3 and 0.03 for 35mm). Even the "equivalent" 25mm lens at 1m and f1.4 has a DOF of 65.5mm. The achieve a similar framing for a 4/3 camera vs a 35mm camera requires either a wider lens or a longer shooting distance. Both of these increase DOF. Shooting a fixed focal length at a fixed aperture and a fixed distance to the subject, with no regard for framing (because you will crop the subject) will actually lead to a shallower DOF because the 4/3 image will need more enlargement to reach the same print size.

But shooting with no regard for framing is impractical in real world usage. If you want shallower DOF you're going to be better off choosing a larger sensor. If you want more DOF then choose a smaller one.

Gordon

You need to re-check those charts! No .. actually shouldn't have seen any chart for this purpose at all. The point of your stress .. get FF for shallower Dof and Compact for deeper .. is not something I disputed at all.

The chart you are seeing is not based on actual focal lengths, but equivalence on different standards and systems. Don't compare latest 25mm pany f1.4 on m4/3 body with 50mm f1.4 ais on nikon ff dslr. Because they are actually based on two totally different focal lengths; actually just half of it. That is why your silly calculators are showing you half of it. The example I gave you was of one lens mounted on two systems. Read it again please.

In Dof formula sensor size is simply not there (just focal length and apperture), its simply because focal lengths are bigger on a set FOV (field of view) at FF than smaller sensors.

You look at charts when you compare two different lenses, you can't do it here because its same lens: fully exposed circle on FF and cropped in the middle at 4/3.

Now talking about real world scenerios, all these discussion forums and review sites with pixel peeping into all possible focal lengths, sensors, appertures etc is far from real world scenerios, but technical side of photography. In real world just chose your camera that sits good in your hands thumb and fingers and go out .. shoot! you will get acceptable IQ and Dof from all ILCs and FF.

Please dont ask for proofs, if you have both camera system and convertor fix your tripod infront of an object, chose your lens (keep it same for both formats) and select two bodies from two different camera systems. Measure the field afterwards and tell me if you getting narrower Dof, yes the FOV will be different and I mentioned it clearly in my first message. I would do that test for you, if I would still have my Nikon D5100 with me, as I said earlier .. I just sold it recently in favor of my GH1 and Pen E-P1.

I know I need to update my signature again

 

[flash]

But I like asking for proof, especially when the words "tested and proven" are used. I did read your post, carefully. And in my reply I gave the DOF for both 4/3 and 35mm sized sensors using the same 50mm lens, aperture and distance, changing only the sensor size. Here is a web based one (I just googled it)? It's not the ones I use regularly.

Online Depth of Field Calculator

Put in the numbers and see if you're right. See if you can get the same lens, aperture and distance to give you the same DOF measurements on different sensor sizes.

Gordon

 

[wolfie]

I shoot my kids a lot and sports is a part of that. The MFT I chose does not do that well (are there any that do? I ask this innocently and without irony)

I used my E-P3 with the 40-150 IIRC zoom last soccer season and frankly has no more difficulty than the previous year with my K-7 and 70-200 AF zoom. I never have been comfortable with CAF on SLR or M4/3, so I continually pump the shutter in SAF mode as I follow the action.
I would suspect any current M43 camera and lens should be up to the job of handling typical family sports. The new OM-D claims to have the fastest AF of any system camera, so I think the slow AF point is out-of -date and can be forgotten as the last gasp of the APS crowd to discredit the new format.

 

[Naveed Akhtar]

But I like asking for proof, especially when the words "tested and proven" are used. I did read your post, carefully. And in my reply I gave the DOF for both 4/3 and 35mm sized sensors using the same 50mm lens, aperture and distance, changing only the sensor size. Here is a web based one (I just googled it)? It's not the ones I use regularly.

Online Depth of Field Calculator

Put in the numbers and see if you're right. See if you can get the same lens, aperture and distance to give you the same DOF measurements on different sensor sizes.

Gordon

Gordon .. I just asked you not to get into Dof calculators .. for this, and look what you did

What you want me to do now .. compare 50mm ff lens with 50mm ff lens? this is not possible .. its same lens and same focal length. How would you do that? some how you are not getting the point.

Search the web man, leave those calculators behind .. dont send me the link of another calculator as a proof please!

 

[Naveed Akhtar]

Here is a result of quick search on google:
Andre's Blog • DOF: 35mm vs. APS-C

Put in the numbers and see if you're right. See if you can get the same lens, aperture and distance to give you the same DOF measurements on different sensor sizes.
Gordon

The reason why you getting different results is because when you select 50mm on 4/3 .. it is NOT .. let me repeat again IT IS NOT 50mm but 25mm focal length.

Regards!