Fuji 23 1.4 WR as ‘35-50mm’ zoom

What about a Sigma 18-50mm f2.8 DC DN Contemporary Lens for Fujifilm X cover the whole range without cropping?

I think in terms of cropping/resolution you should be fine. I actually experimented with using my Viltrox 13mm as a pseudo ~20mm using the 1.4 digital teleconverter on my X-T5 - the results were fine up to a point. When you start pixel peeping at 100-200% you can definitely see the drop off in detail - but at a global level it looked perfect fine.

The one thing that you would lose however is the change in perspective that different focal lengths give you. This is something I’ve really only come to appreciate lately but it can make a massive difference when composing your shot - particularly where subject in relation to background perspective is important. You would be surprised at the difference 23mm and 35mm focal lengths make to the background in relation to the subject.

GMacF wrote:

The one thing that you would lose however is the change in perspective that different focal lengths give you. This is something I’ve really only come to appreciate lately but it can make a massive difference when composing your shot - particularly where subject in relation to background perspective is important. You would be surprised at the difference 23mm and 35mm focal lengths make to the background in relation to the subject.

Eh? Focal length doesn’t change perspective. If you crop a 23 to the equivalent of a 35 then the only differences are (a) reduced pixel count compared to a using a 35mm lens to project onto the whole sensor and (b) you end up with depth of field equivalent to using a stop or so down if you had used the 35. It’s basically using a 23mm lens on a Four Thirds sensor: it’s (near enough) a 50mm full frame equivalent, the same as a 35mm lens of APS-C or 50mm on full frame. The perspective depends only on where the camera is.

To my mind the only issue with sports finders and cropping (assuming that you don’t take it so far that the image quality crumbles) is that I like to see the final image in the viewfinder, not a load of stuff around it even if there are framelines, because that throws me off when it comes to visually balancing the image.

GMacF wrote:

I think in terms of cropping/resolution you should be fine. I actually experimented with using my Viltrox 13mm as a pseudo ~20mm using the 1.4 digital teleconverter on my X-T5 - the results were fine up to a point. When you start pixel peeping at 100-200% you can definitely see the drop off in detail - but at a global level it looked perfect fine.

The one thing that you would lose however is the change in perspective that different focal lengths give you. This is something I’ve really only come to appreciate lately but it can make a massive difference when composing your shot - particularly where subject in relation to background perspective is important. You would be surprised at the difference 23mm and 35mm focal lengths make to the background in relation to the subject.

This is exactly how I use the 13mm, the 2x is to much of a drop but 1.4x works perfectly for everyday shooting when I just want a 1 lens ultra wide.

Strangefinder wrote:

Andrewcn wrote:

Yes, I hadn’t considered that, probably because it’s not WR.

Is there much sharpness difference?

The X-mount & L-mount DC DN Sigmas all have basic weather resistance — not the comprehensive WR of the (recent) ART series etc, but better than non-WR Fuji lenses.

I've used it in the rain with no issues to speak of, light rain.

Andrewcn wrote:

I’m thinking of buying the 23 1.4 WR to cover the focal lengths 35, 40 and 50mm. I would make to of the sports finder mode and the1.4 digital crop.

Are there any downsides to this? I only print up to A3 and so the loss of resolution shouldn’t matter.

90% of what I shoot is in this focal range and it seems a good, lightweight, one lens coption.

Comments please.

Sure, why not?  Regardless of what lens I'm using, I routinely crop.  With a 23, the effective focal length is 35 so you're good there.  To crop to 50mm (assuming you mean effective FL of 75mm), that's a 2x crop but it's certainly feasible.

While a good zoom would provide better IQ than a 2x crop, image IQ shouldn't be always be the deciding factor.

Jeff Biscuits wrote:

GMacF wrote:

The one thing that you would lose however is the change in perspective that different focal lengths give you. This is something I’ve really only come to appreciate lately but it can make a massive difference when composing your shot - particularly where subject in relation to background perspective is important. You would be surprised at the difference 23mm and 35mm focal lengths make to the background in relation to the subject.

Eh? Focal length doesn’t change perspective. If you crop a 23 to the equivalent of a 35 then the only differences are (a) reduced pixel count compared to a using a 35mm lens to project onto the whole sensor and (b) you end up with depth of field equivalent to using a stop or so down if you had used the 35. It’s basically using a 23mm lens on a Four Thirds sensor: it’s (near enough) a 50mm full frame equivalent, the same as a 35mm lens of APS-C or 50mm on full frame. The perspective depends only on where the camera is.

Apologies if my wording was out, this is what I meant. As in, there's a significant difference between simply cropping a shot and reframing a similar shot(s) at native 23mm & 35mm focal lengths respectively - however I do understand this isn't specifically what the OP was asking about.

And yes the depth of field difference is quite noticeable as well.

To my mind the only issue with sports finders and cropping (assuming that you don’t take it so far that the image quality crumbles) is that I like to see the final image in the viewfinder, not a load of stuff around it even if there are framelines, because that throws me off when it comes to visually balancing the image.

Strangefinder wrote:

Andrewcn wrote:

Yes, I hadn’t considered that, probably because it’s not WR.

Is there much sharpness difference?

The X-mount & L-mount DC DN Sigmas all have basic weather resistance — not the comprehensive WR of the (recent) ART series etc, but better than non-WR Fuji lenses.

That’s good since I’m more concerned with dust and dog hair getting into the lens than I am rain.

Andrewcn wrote:

I’m thinking of buying the 23 1.4 WR to cover the focal lengths 35, 40 and 50mm. I would make to of the sports finder mode and the1.4 digital crop.

Some thibgs you should consider:

- The digital teleconverter doesn't affect the raw: you end with a cropped jpeg and a complete raw (the sports finder does crop the raw AFAIK)

- The sports finder and the teleconverter are 2 different options on the menus, so you'll need 2 buttons to use both option (you can't assign both options to the same button)

- The sports finder can only be used with the mechanical shutter

Are there any downsides to this? I only print up to A3 and so the loss of resolution shouldn’t matter.

90% of what I shoot is in this focal range and it seems a good, lightweight, one lens coption.

Comments please.

If you know how a cropped sensor affects IQ, then this is exactly the same: it will change your DoF, DR, resolution and noise to signal ratio

I printed a x1.5 crop to a size of 30cmx45cm (bigger than DinA3+) and it is comoletely fine

Jeff Biscuits wrote:

GMacF wrote:

The one thing that you would lose however is the change in perspective that different focal lengths give you. This is something I’ve really only come to appreciate lately but it can make a massive difference when composing your shot - particularly where subject in relation to background perspective is important. You would be surprised at the difference 23mm and 35mm focal lengths make to the background in relation to the subject.

Eh? Focal length doesn’t change perspective.

Wrong. Extreme example: Laowa 9/2.8 vs Fujinon XF 90/2. So it is basically 9mm focal length vs 90mm focal length. You telling me, that those lenes would give same perspective?

BeatX wrote:

Jeff Biscuits wrote:

Eh? Focal length doesn’t change perspective.

Wrong. Extreme example: Laowa 9/2.8 vs Fujinon XF 90/2. So it is basically 9mm focal length vs 90mm focal length. You telling me, that those lenes would give same perspective?

Yes.

We’re talking about cropping an image from the wide lens to give the same view as you would get from the long lens.

Stand in one place, and take my X-Pro2 with the XF 18/2 in one hand, and my Ricoh GR Digital IV in the other. They both have the same field of view. One achieves it with a pen 18mm lens and an APS-C sensor, the other with a 6mm lens and a 1/1.7” sensor.

When you crop, you’re just using a smaller (part of the) sensor, so a shorter lens gives the same field of view as a longer lens on the full sensor area.

You change perspective by moving the camera.

Jeff Biscuits wrote:

BeatX wrote:

Jeff Biscuits wrote:

Eh? Focal length doesn’t change perspective.

Wrong. Extreme example: Laowa 9/2.8 vs Fujinon XF 90/2. So it is basically 9mm focal length vs 90mm focal length. You telling me, that those lenes would give same perspective?

Yes.

We’re talking about cropping an image from the wide lens to give the same view as you would get from the long lens.

Stand in one place, and take my X-Pro2 with the XF 18/2 in one hand, and my Ricoh GR Digital IV in the other. They both have the same field of view. One achieves it with a pen 18mm lens and an APS-C sensor, the other with a 6mm lens and a 1/1.7” sensor.

When you crop, you’re just using a smaller (part of the) sensor, so a shorter lens gives the same field of view as a longer lens on the full sensor area.

You change perspective by moving the camera.

Hmmm, interestint point. I didn't thought about it this way. I need to run some tests to confirm Your words, unfortunately I don't have access to any lenses than those two I have listed in my signature. But I will keep in mind to check it in the future, when there will be opportunity. Thanks

You should confirm it yourself, just to understand it better, but he's 100% correct.

Let me google it for you

emirco wrote:

Let me google it for you

That answer is wrong. As said before, cropping IS the same as using another focal length when you consider perspective (it affects other things I listed: resolution, DoF, DR and noise to signal ratio)

Zinch wrote:

emirco wrote:

Let me google it for you

That answer is wrong. As said before, cropping IS the same as using another focal length when you consider perspective (it affects other things I listed: resolution, DoF, DR and noise to signal ratio)

Yes quite right. As Jeff pointed out on my initial reply, perspective does NOT change when just cropping. I admit my wording was off when what I meant was perspective changes when framing (and re-framing) at different focal lengths.

I DID do some testing so hopefully this clears things up:

Below is a shot taken @23mm with the 1.4 digital teleconverter on (so approx 35mm equiv):

and one taken at 35mm:

To further demonstrate below are two shots, one taken @16mm (with 2x crop) and one taken @35mm - both images have same perspective but different DOF, noise etc:

Conversely, the point I was making initially (and what others I believe are making) is the change in perspective when re-framing a shot. Below is a shot taken @23mm then re-taken @35mm but reframed so the subject (lens hood) is approx the same size:

I think it would work well. In practice you may just find that you ‘zoom’ more with your feet. I find primes more satisfying to use and the extra aperture size is useful.  You probably only need 5-8 MP to get a satisfactory print at A3. I’ve printed 16 MP to A2 with stunning results (simply judged on sharpness/detail) and A3 is half the area.