Fast 50 or fast 35 on crop sensor?

3dit0r

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Guys,

On my FF cameras I was used to leaving a fast 50 1.4 semi-permanently glued on the front and getting probably 50% of all shots with that combo. Nice FOV for street and informal portraits, and good OOF for subject separation and stumble-upon still-life's, good light gathering for nightlifes.

Question: now I'm on a crop sensor (NEX-6) should I get a fast 50 again to sit in between the 10-18 and 55-210 OR should I get a fast 35? There are two reasonably priced Sony lenses (35 f/1.8 OSS and 50 f/1.8 OSS). I don't know if the 50 is going to have a slightly too tight AOV, or alternatively if I'm going to miss the amount of OOF blur I can get with a 50mm if I choose the 35mm to match the AOV of the 50...

Any opinions or experience, please? What is the extent of difference between a 50 1.8 and 35 1.8 in terms of OOF blur at max aperture? I have two fast 50s but no fast 35 of my own to compare? Equally, is it really just a case of taking a few steps back with a 50 to get a 35mm AOV, or does it not quite work that way with a distant subject?

Cheers,

James
 
I spent a long time with a Canon 50d, and my main lenses were my 50f1.8 (later a 50f1.4), and a 35f2.

Obviously, the Canon and Sony lenses will likely perform differently, so I'm going to stick to the field of view question.

I found that the images made by the 50 were much more pleasing, and I would get more photos that I would be proud of... however, on the crop sensor, the 50 is pretty tight, and when shooting indoors it would be difficult to get photos of more than two or three people in the frame-- and good luck getting any of the environment in the shot without having to go across the street. The 35 makes it much easier to do this, especially indoors... but it just lacks that je ne sais quoi possessed by the 50.
 
Thanks for the reply!

Yeah, that's kind of what I was afraid of- that I'm just not quite going to get the versatility and, as you so rightly put it, je-ne-sais quoi in one lens? Perhaps I have to resign myself to getting both. I already have a fast 50 1.4 with an adapter, so maybe I should get the 35 1.8... I used a 35 summicron for years on my M6, but having gone 50 1.4 with my D700 afterwards, I loved the results much better, tbh.

James
 
I just replicate the focal lengths I use on film bodies with my NEX-7. I use a 24, 35 & 75 with film, and a 15, 24 and 50 on the NEX. If I have one lens it's a 50, so that would be a 35 on the NEX. I use smaller apertures with crop bodies so fast lenses aren't necessary.
 
Sometimes when I put the Nokton 40mm f/1.4 on my GXR, it stays there for months on end. Nothing beats a nice, fast wide- to long- normal lens. ;-)

40mm on APS-C just seems perfect to me for a lot of one-lens shooting. 50mm seems a hair too tight. 35mm is fine too ... kind of the 'standard' normal ... but after the 40mm, 28mm is my favorite (a wide-normal). The Ultron 28mm f/2 sits in this slot for me.

G
 
I use a 35mm and a 28mm on the digitals I have. But I don't use digital much, certainly not something I really care about. Although today, which I really didn't care about, I did a job for the local theater using digital. Now I have to spend hours editing: uuuuugh.
 
Unless you're 100% certain that you always want the FOV of the 50, the answer is easy: take the 35.

Don't forget that if you first crop and then compensate with extra enlargement of an image, DOF becomes shallower than with the uncropped image! DOF is governed by physical aperture and magnification. That means that a 35/1.8 is much more versatile than you first would think on a camera like the NEX-6 which has enough resolution to allow cropping to the FOV of a 50.
 
Thanks guys,

I had a brainwave and went into Lightroom to look at my favourite photos and groups of photos (particularly a holiday to the South of France where I got my highest volume of shots I love to this day). I was using the D700 then, and had the 24-70 f/2.8 standard zoom and the 50 f/1.4 AF-S G and it's remarkable looking back on that now and seeing what proportion of those shots was at 50mm, not just with the 50mm prime attached, but how often I was near 50mm on the zoom, without even being aware - clearly my eye likes that slightly tighter than real life, and fairly natural perspective!

By far the highest proportion of shots was at or very near 50mm, even street shots and landscapes, which surprised me. The other most used focal lengths were 35mm, 70mm (although I sometimes wanted longer than that zoom lens and had to crop in- not painless on the D700 with only 12mp) and 24mm, the latter being used mainly for interiors of old churches, and the very odd landscape. Makes me wonder why I paid all that dough for the zoom (and lugged the bulky, heavy thing around), in fact, and maybe a worthwhile exercise to do before buying any lens?

So, in fact, I think the 35 f/1.8 OSS is a no-brainer for me- it'll probably sit on the camera 60-70% of the time, with the 10-18 and 55-210 for different perspectives. I have a 50 f/1.4 and 85 1.4 C/Y Zeiss and a Novoflex adapter already, so I'll just live without auto aperture and AF for when I need those for portraits and save my other pennies for the upcoming FF NEX ;)

By the way, Peter, can you elaborate on the last post?
"Don't forget that if you first crop and then compensate with extra enlargement of an image, DOF becomes shallower than with the uncropped image! DOF is governed by physical aperture and magnification. That means that a 35/1.8 is much more versatile than you first would think on a camera like the NEX-6 which has enough resolution to allow cropping to the FOV of a 50."
I couldn't get my head around what that means - I'm probably misinterpreting it, but I would have thought from experience that even if you crop in on a shot taken with a 35mm focal length to where a 50mm frameline would have been, you'd still have greater DOF and angularity with the 35mm...? If you could clarify I'd be interested!
 
By the way, Peter, can you elaborate on the last post?
Let's see..

Suppose you shoot something with the 50. Sensor size is ca. 24mm wide, then to print a 10x15cm you have a 6.25x enlargement of the frame.

Now shoot with a 35, and crop to the FOV of a 50. You use a portion of the sensor that's ca. 18mm wide. To print a 10x15 you have a 8.3x enlargement.

Assume that in the print, you define 0.1mm as the resolution which lies on the edge of DOF, then for the uncropped 50mm/1.8, the required sensor resolution is 0.1/6.25 = 0.016mm. And for the cropped 35/1.8 the required sensor resolution is 0.1/8.3 = 0.012mmm.

Put those values in a DOF program, and for e.g. a subject on 3m distance you find

For the 50/1.8 (set coc=0.016mm), closest/furthest is 2.9m-3.11m
For the uncropped 35/1.8 (set coc=0.016mm), closest/furthest is 2.8m-3.22m

and, surprise:
For the cropped 35/1.8 (coc=0.012mm), closest/furthest is 2.85m-3.16m

Not as shallow a DOF as you can get with the 50, but also not as wide as you'd expect without factoring in print size..
 
Let's see..

Suppose you shoot something with the 50. Sensor size is ca. 24mm wide, then to print a 10x15cm you have a 6.25x enlargement of the frame.

Now shoot with a 35, and crop to the FOV of a 50. You use a portion of the sensor that's ca. 18mm wide. To print a 10x15 you have a 8.3x enlargement.

Assume that in the print, you define 0.1mm as the resolution which lies on the edge of DOF, then for the uncropped 50mm/1.8, the required sensor resolution is 0.1/6.25 = 0.016mm. And for the cropped 35/1.8 the required sensor resolution is 0.1/8.3 = 0.012mmm.

Put those values in a DOF program, and for e.g. a subject on 3m distance you find

For the 50/1.8 (set coc=0.016mm), closest/furthest is 2.9m-3.11m
For the uncropped 35/1.8 (set coc=0.016mm), closest/furthest is 2.8m-3.22m

and, surprise:
For the cropped 35/1.8 (coc=0.012mm), closest/furthest is 2.85m-3.16m

Not as shallow a DOF as you can get with the 50, but also not as wide as you'd expect without factoring in print size..

Interesting, I'd never realised. Thanks! :)
 
I had 35 and 50 1.4 lenses for my Canon FF and sure do miss them on the Nex. 50 1.4, in particular, is a classic configuration. To my knowledge the only small sized, reasonably priced option is the Voigtlander 35. I use the Sigma 30 and 19 but wish they were faster.

If you liked 50 so much before Nex, why not stick with it and go with the Sony 35? Pretty fast and OSS. I kinda wish I'd gone that way.

John
 
I use a 35mm and a 28mm on the digitals I have. But I don't use digital much, certainly not something I really care about. Although today, which I really didn't care about, I did a job for the local theater using digital. Now I have to spend hours editing: uuuuugh.

This is a common complaint. I always have to ask ... Do you have all your film work processed and printed for you? Do you do any editing with it?

I certainly do when I'm shooting film, and culling/processing/producing client proofs for 100 exposures of digital capture takes me about 20 minutes compared to about 5 hours culling, scanning, and rendering 35mm or 6x6cm film exposures, given quick-turn negative processing at the local pro lab. In the darkroom, doing the film work would be about a full day's work including the film processing...

I'm curious as to your film process and why it is so much faster for you than your digital process, when the reverse is always the case for me.

OP: sorry for the digression. ;-)

G
 
I had 35 and 50 1.4 lenses for my Canon FF and sure do miss them on the Nex. 50 1.4, in particular, is a classic configuration. To my knowledge the only small sized, reasonably priced option is the Voigtlander 35. I use the Sigma 30 and 19 but wish they were faster.

If you liked 50 so much before Nex, why not stick with it and go with the Sony 35? Pretty fast and OSS. I kinda wish I'd gone that way.

John

Hi John,

Yeah, I did some tests yesterday with my 50 1.4 and 35 2.8 by setting the 50 no wider than 2.8 to compare. While the 50 is by far a better portrait lens, IMO, for many of the shots I take while out and about which place people in their environments, the 35 on a crop sensor is better as I'm too tight in on people otherwise it seems (doubtless I'd get used to this over time and adjust my shooting practices, but I've been using a fast 50 for years and intend to switch to FF NEX when it arrives, so this is temporary and not worth re-learning too much?). I think I'll keep my manual 50 1.4 for portrait work, and just get the AF Sony 35 1.8 OSS for my 'walkaround' lens.

That Zeiss 24 1.8 is awfully tempting too, but too much outlay when it won't cover FF when I upgrade ;)

Cheers,

James
 
This is a common complaint. I always have to ask ... Do you have all your film work processed and printed for you? Do you do any editing with it?

I certainly do when I'm shooting film, and culling/processing/producing client proofs for 100 exposures of digital capture takes me about 20 minutes compared to about 5 hours culling, scanning, and rendering 35mm or 6x6cm film exposures, given quick-turn negative processing at the local pro lab. In the darkroom, doing the film work would be about a full day's work including the film processing...

I'm curious as to your film process and why it is so much faster for you than your digital process, when the reverse is always the case for me.

OP: sorry for the digression. ;-)

G

I totally agree- I do not miss the darkroom one jot, except in a rare moment of sentimentality (although I miss the tactile feel of using an M6). Then I remind myself of the chore it involved when I can simply open up Lightroom! I'm not one for heavy digital editing, just a few tweaks, much more easily accomplished than with test prints, etc., and I'm usually done. Having been a late switcher to digital, I must say I have never looked back, but I did wait until FF digital had come of age and bought a S/H 1DsMkii initially. The results blew me away. The fact I'm getting significantly better results (IMO) than that from a £600 NEX now which is so light to carry round I hardly notice it, is testament to just what an explosion of amazing gear has come out in a few years. It is a hugely exciting time to be into photography, or at least I find it so!
 
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