Tuesday 2 December 2014

Portrait lenses - native vs legacy

Since my entry into micro 43, over 5 years ago, I have been interested in the fact that I can take advantage of a pool of very well priced 35mm lenses which perform fantastically on micro 43. To me back then m43 was what 35mm was to Medium Format: lighter and smaller but with good image quality. For exactly the same reasons as 35mm had advantage over medium format too. You see a "standard" lens for medium format is 100mm but a standard lens for 35mm is 50mm and needs to cover a fraction of the area (making it cheaper to make optically good).

why

In the past I have been a user of legacy lenses on m43 simply because when (in 2009) the system was launched there were no alternatives. My G1 came with a 14-45mm zoom and that about rounds out what was available then too. Wanting to have a bit more telephoto and a more shallow DoF I turned to the ready supply of 35mm lenses to "test the water" ... my first purchase was an nFD 50mm f1.8, soon to be followed by an OM 50mm f1.8 ... I wasn't satisfied with the FD image quality. I picked the OM because in the past I'd had OM gear and loved the image quality.

Since then I've tried and tested many 35mm legacy lenses and often been left wondering what the native alternative would be like (where it existed) but was reticent to drop the money onto it.

Reticent because (despite how it seems) I don't have GAS and because the prices of the native lenses were just more than I felt they would yeild in benefits.

Having compared the FD 50 f1.4 (note that's not the first one mentioned above) to my OM 50 f1.8 quite favorably , and compared my FD 50mm f1.4 to a OM 100mm f2.8 on a full frame (because they are equivalent) I have always wondered how well the relatively new native 45mm f1.8 would compare to my OM 50mm f1.8

A recent drop in prices for a sale made me decide to put $300 into this question and see if I'll keep a valuable lens or learn that I'll just sell it again (as I did with my Sigma 30mm).

Quick Summary

I have not made a decision on this yet, but I'll probably keep the 45mm because it works so well on my GF series camera in helping it be a compact system. I have a GH1 and a GF1 which while similar, perform entirely different roles for me. There really is nothing like this sort of lens on the GF (or say a GM if I was inclined) to give me a compact and excellent camera system.

Were I to have just an SLR-alike body (such as my GH or an OM-D) then I would simply sell this as to me the 45mm offers so little benefit as to be pointless. If you are hopeless at manual focus and unwilling to learn then the 45mm fills that role, but if you engage with your subject and are a photographer (not a snapper) then the legacy OM lens (at 1/10th of the price) offers equal quality.

The contrast and bokeh of the 45 is not significantly better than my OM, which I know is almost as good as using a 100mm on a full frame.

The Lenses

Ok, so below is my OM 50mm f1.8 beside the Olympus 45mm f1.8. I think there is not much in it for size between them. Certainly when mounted on a SLR style body ...


You can see that they are both compact lenses and for manual focus work to be honest the OM lens is nicer to use. The only benefit that the Oly 45 has is that it activates the focus by wire viewfinder zooming as soon as you turn the focus ring (assuming you don't have the camera in AF mode ...)


The fact that you have to put the camera into MF mode to do this is a drag because you need to remember to do that when you change back to another lens (or want it to AF when you pass it to your wife / husband or friend).

Neither has a substantial advantage over the other in terms of carrying in a pocket or backpack.
While the Oly 45 has integrated Aperture control (its a native electronic mount right), if you are going to dial in anything less than f2.8 then the differences between it and the kit 14-45mm zoom rapidly vanish. Seriously don't under estimate how good the 14-45 is at the 45 end. When you compare the Oly at f5.6 its no longer at its "DxO" best anymore.

Sample Images

Ok, I went over to my neighbors place and took a bunch of shots of him working in his shed on some task. I didn't focus on his face, because I'd like to preserve his privacy. Howver these are about the sort of distance where a f1.8 setting will set a 45mm aside from a f5.6 setting on a zoom. Further away and the DoF differences shrink, closer and the DoF will be too shallow to be useful on the f1.8 (a point often ignored or simply not understood)

So, lets look at the thumbnails from the images without telling you which is which ..
all look similar to you? Yep me too ... So this will tell you straight up that unless there is some major issue in 'fine details' that when it comes to making an image these lenses are in the same ballpark.

Details

Ok ... lets pick two images, one from the 45 and one from the 50. The images were shot hand held and I was standing more or less in the same spot (moved a little to the left or right as one may do when doing a portrait shoot).

The overview:


and then a 50% magnification (because I've found that at 50% pixel view it translates to just about what you'd see on a print).


Now another image from the other lens:


and the 50% pixel view...


So which was which?

I used the Oly 45 exclusively on AF because I wanted to test also how well the camera picks its focus location. That's a critical point when considering the 45, because one of the key selling points for me is AF ... I mean what else am I paying that extra $250 for? How it feels in my hand?

I found that while the Oly 45 was good, it picked focus slightly differently to where I exactly wanted it to be. That caused the point of human interest to be softer for me than I wished it. If you look at the screen grabs of the 50% pixel view (at 100% which means you'll need to open the image in a new tab) you can see that evident in the shots here.

Well perhaps knowing that you can see it, but in case you still can't I'll tell you that image p1110278.jpg was from the 45mm and p1110281.jpg was from the OM 50

Conclusions

Well to me this makes clear that I'd already been standing in the field with the greener grass. The OM50mm f1.8 has given me many great keepers (and almost no duds) in the years I've already been using it for. The image quality is undifferentiable from the 45 and to be honest the 45 AF speed is vin ordinair, quite to contrary to what people seem to Wang on about....

You'll have to make your own decision about the relative merits of even having AF, but for me (and my eyesight) to use this lens on my GF means I can get AF (and I need it on a compact) but if I wasn't going to use the lens there and was only using it on my GH body I would perhaps not bother.

To me the combination of:
  • 14mm f2.5 + GWC-1 wide adapter
  • 20mm f1.7
  • and this 45mm f1.8
makes the GF (or similar compact) into a great light and compact travel outfit. I had a GF which I sold and soon then rebought another GF because I realised that its nice to have both. In the world of second hand stuff the $100 that I paid for the GF body makes it irresistible for what it provides. So I'll probably be keeping the 45 ... however if I had (as one of my friends does) an OM-D body I'd likely be selling the 45 as the OM50mm f1.8 is just so bloody good.

Lastly, the only other similar comparison I've found is this one over at Tyson Robichaud's site. I think I've known Tyson for some time (assuming its the same Tyson who commented on a post some years ago) and its been interesting to see his development too.

I find that Tyson has summed up (in a slightly different manner to me) well with these comments:
The ease and usefulness of auto focus is something that many of us may take for granted.  It isn’t until I remove that feature that I begin to realize how differently I tend to shoot, compose and interact with subjects. I often enjoy shooting with a manual focus lens as it tends to slow me down and add an air of intentionality in my shooting that often gets overlooked when I’m out and about firing away.
 Indeed, and I'd add to that the by having "stop down" view engaged "automatically" in the manual focus lens you can see immediately the changes in DoF and look of the image which you may forget to do when blazing away with an AF lens.
Either way, and depending on how you look at it, one could be “better” than the other depending on personal taste.  To me, both are good, but different showing that different lenses at the same focal length can indeed produce two very different looking pictures.
 although with my lens comparison I'd change that to "produce slightly different looking images"

Its also a good post and provides many other comparisons of static identical targets (where the subject does not move nor the position does not move unlike here) for those who would like to see things done that way. I recommend reading his post if you have are considering the Oly 45.

Hope that Helps

1 comment:

Tyson Robichaud said...

What may not come through accurately in our tests is just how small and light this little powerhouse of a lens really is. I often have it fastened to the GM1, which makes for a very compact, very light weight pocket portrait setup with very good quality.

Great writeup, and thanks for the mention!

Cheers,
Tyson