[Schlimperdibix]

Hi Klaus,

 

Thanks for putting this together!

 

However, there were a few things that I believe should be mentioned.

1) selected lenses for FF and µFT are for mirrorless while Pentax lenses for APS-C are for DSLR (leave out K-01 which takes DSLR lenses w/o adapter). For telelenses you can argue that this is in favour of DSLR because of the shorter construction of the lens only.

2) as you rightly said, the Pentax DA* 60-250/F4 doesn't really fit but if you replace the Sony FE with Canon/Nikon/Sigma 80/100-400 F4.5-5.6 which is more the range of the Pentax, you quickly end up in the 1340-1750 g range which is more than the Pentax lens even when correcting for slightly faster lens at lower focal lengths.

3) when selecting a more traditional focal length for telezoom (70/80-200) the situation between FF and APS-C also looks different:

Pentax DA* 50-135 F2.8 - 685 g; 136 mm long vs Canon 760 g; 172 mm long

 

Besides the very informative text, your lens selection goes more in a mirrorless vs dSLR rather than a sensor size comparison.

[Brightcolours]

Hi Klaus,

 

Thanks for putting this together!

 

However, there were a few things that I believe should be mentioned.

1) selected lenses for FF and µFT are for mirrorless while Pentax lenses for APS-C are for DSLR (leave out K-01 which takes DSLR lenses w/o adapter). For telelenses you can argue that this is in favour of DSLR because of the shorter construction of the lens only.

2) as you rightly said, the Pentax DA* 60-250/F4 doesn't really fit but if you replace the Sony FE with Canon/Nikon/Sigma 80/100-400 F4.5-5.6 which is more the range of the Pentax, you quickly end up in the 1340-1750 g range which is more than the Pentax lens even when correcting for slightly faster lens at lower focal lengths.

3) when selecting a more traditional focal length for telezoom (70/80-200) the situation between FF and APS-C also looks different:

Pentax DA* 50-135 F2.8 - 685 g; 136 mm long vs Canon 760 g; 172 mm long

 

Besides the very informative text, your lens selection goes more in a mirrorless vs dSLR rather than a sensor size comparison.

1) : sizes of lenses only matter for bag space purposes. In that sense it makes no sense to point out the mirror box difference?

2) : the Pentax f4 lens is slower of the whole range (f6) in equivalence terms. So its weight advantage compared to a f4.5-5.6 lens would be due to that, making it a wonky comparison too.

Klaus could also have chosen one of the many 70-300mm lenses for FF DSLRs, the choice for the FE lens is fine and not a mirrorless vs DSLR skewed choice.

3) : A Pentax f2.8 lens is slightly slower (f4.2 FF equivalent) and the Canon EF 70-200mm f4 L USM weighs 705 grams. Which goes to show, one can always skew things in whatever favour (do you happen to shoot Pentax?).

[Schlimperdibix]

2) : the Pentax f4 lens is slower of the whole range (f6) in equivalence terms. So its weight advantage compared to a f4.5-5.6 lens would be due to that, making it a wonky comparison too.

Klaus could also have chosen one of the many 70-300mm lenses for FF DSLRs, the choice for the FE lens is fine and not a mirrorless vs DSLR skewed choice.

3) : A Pentax f2.8 lens is slightly slower (f4.2 FF equivalent) and the Canon EF 70-200mm f4 L USM weighs 705 grams. Which goes to show, one can always skew things in whatever favour (do you happen to shoot Pentax?).

2) It was Klaus that set F4 in APS-C equivalent to F5.6 in FF terms, not me. The reason I picked the 80/100-400 was because that would fit with the APS-C lens selected and as there ias no 50-200 F4 in APS-C I would rather go for either longer as I did or shorter as I did in 3)

3) again, it was Klaus who set 2.8 APS-C equivalent to F4 in FF. It was also him who picked Pentax lenses as a representative for APS-C lenses. W.r.t. the Canon EF 70-200mm f4 L USM, that's the old obsolete lens w/o IS. The current model weighs 760 g and I think it's fair to compare current lenses.

[Brightcolours]

2) It was Klaus that set F4 in APS-C equivalent to F5.6 in FF terms, not me. The reason I picked the 80/100-400 was because that would fit with the APS-C lens selected and as there ias no 50-200 F4 in APS-C I would rather go for either longer as I did or shorter as I did in 3)

3) again, it was Klaus who set 2.8 APS-C equivalent to F4 in FF. It was also him who picked Pentax lenses as a representative for APS-C lenses. W.r.t. the Canon EF 70-200mm f4 L USM, that's the old obsolete lens w/o IS. The current model weighs 760 g and I think it's fair to compare current lenses.

2) The 70-200mm f4 FF lenses are a much better match for the comparison, for APS-C, though.

3) The Canon EF 70-200mm f4 L USM is not obsolete, not in performance and not in the price lists. It is still a current model. The Pentax does not have IS either, so lens wise it is a fine comparison. The Pentax got sold as Tokina for a while, but thatone is indeed obsolete.

 

It really makes a bit more sense to use a 70-200mm f4 lens for that part of the comparison. One can choose Nikon, Sony, Canon.

[Klaus]

You are aware that you are a bit nit-picky there. 

 

Especially considering the fact that nobody knows whether the f/4 lens is actually really f/4 and not f/3.8 or f/4.2 nor whether the focal lengths are correct (which they never are really).

 

Regarding the lens examples you will always be able to come up with an exception to the rule because of some special design aspect.

 

The whole point is that there isn't really a difference when considering the grand concept - plus/minus. Nobody will notice a 10-15% difference in the real life anyway. It just doesn't matter.

[Klaus]

BTW, just to illustrate an error margin that is a "little" higher ...  

[toni-a]

However, PERSONALLY I don't care too much about this topic. 

Me neither, I never calculate DOF before shooting, I use full frame and APS-C simultaneously and it doesn't really matter in real life.

I took 5K pics in 2 weeks so you imagine how active I am, and I was using two bodies , and never cared for the sensor size.

[Schlimperdibix]

2) The 70-200mm f4 FF lenses are a much better match for the comparison, for APS-C, though.

3) The Canon EF 70-200mm f4 L USM is not obsolete, not in performance and not in the price lists. It is still a current model. The Pentax does not have IS either, so lens wise it is a fine comparison. The Pentax got sold as Tokina for a while, but thatone is indeed obsolete.

 

It really makes a bit more sense to use a 70-200mm f4 lens for that part of the comparison. One can choose Nikon, Sony, Canon.

The problem is that for telezoom lenses there are not many high quality (build-wise) dedicated APS-C lenses on the market which is probably why Klaus selected the Pentax DA* lens. However, if you want to do fair comparisons you have to pick those pairs that match. So you could select the following pairs:

1) Pentax 50-135/F2.8 vs Canon/Nikon 70-200/F4 - same equivalent focal length and similar speed (2.8x1.53=4.28)

2) Pentax 60-250/F2.8 vs Canon/Nikon 100-400/F4 - similar equivalent focal length (90-380 for Pentax) and speed

These two pairs are also comparable on a build quality (non-budget; environmentally sealed).

 

Looking on a comparison of the Canon 70-200/F4 vs a Canon 70-300/F4-5.6, which doesn't match that nicely neither on the focal length (short end) nor on the speed, you would need to pick the "L" version from Canon to have comparable lenses. Weight: 760g vs 1050 g

 

As for missing IS, Pentax has in-body IS so it wouldn't make much sense to add this to their lenses.

 

At the end of the day it's more a question of what camera-lens(es) combo better fits to your needs and not so much FF vs APS-C vs µFT.

[Klaus]

You will find exceptions regarding concrete lens example but this is pointless, really.

 

I can even come up with a mathematical proof:

FF 50mm f/2.8

APS-C: 32mm f/1.8

MFT: 25mm f/1.4

 

What is the diameter of the aperture (in mm)? And what does this mean for the idealized constructions of these lenses ?

[Brightcolours]

The problem is that for telezoom lenses there are not many high quality (build-wise) dedicated APS-C lenses on the market which is probably why Klaus selected the Pentax DA* lens. However, if you want to do fair comparisons you have to pick those pairs that match. So you could select the following pairs:

1) Pentax 50-135/F2.8 vs Canon/Nikon 70-200/F4 - same equivalent focal length and similar speed (2.8x1.53=4.28)

2) Pentax 60-250/F2.8 vs Canon/Nikon 100-400/F4 - similar equivalent focal length (90-380 for Pentax) and speed

These two pairs are also comparable on a build quality (non-budget; environmentally sealed).

 

Looking on a comparison of the Canon 70-200/F4 vs a Canon 70-300/F4-5.6, which doesn't match that nicely neither on the focal length (short end) nor on the speed, you would need to pick the "L" version from Canon to have comparable lenses. Weight: 760g vs 1050 g

 

As for missing IS, Pentax has in-body IS so it wouldn't make much sense to add this to their lenses.

 

At the end of the day it's more a question of what camera-lens(es) combo better fits to your needs and not so much FF vs APS-C vs µFT.

You can simply pick the 70-200mm f4's for APS-C. Does it matter in any way that they are "FF" lenses? No.