[pschlute]

I use to shoot 3 formats; FF (K1ii), KP and my Samsung S10.

For object isolation I pick my K1ii with K35F2.0 K50F1.2 or K135F2.5. I realy like the old style rendering of these.
My KP get out of the box for portability with my M20F4.0, M28F2.8, M50F1.7, M85F2.0 or M200F4.0. One stop down all these lenses work great on APS-C.
My smartphone is always & everywhere... Simple sharp shots, bit grainy and flat images.

My few AF-lenses are put on when I give the cam to family members... :-)

You have a great selection of lenses....but you didn't actually answer my question

---------- Post added 05-06-21 at 11:10 PM ----------

I use aps-c and do not feel as if I am missing anything, I can get narrow enough DOF to suit my needs without a ridiculously expensive lens. But maybe some people do.

+1

I have used 35mm film cameras; then aps--c DSLR cameras; and now FF DSLR cameras.

I have never agonised about DOF with any of the formats...I get what I get.

[shyrsio]

the more reach the lens has in relation to the aperture the more shallow dof you will get. the 85.1/4 is waay shallower to the 50/1.4 in my eyes.

[Sidney Porter]

I do not understand lens engineering but my observation is that a fast 50 and a pancake 40 are easy to make. I am sure some one can explain. The change to apsc didn't magically make it easier / cheaper to make a fast 28 or 35.

[Serkevan]

I do not understand lens engineering but my observation is that a fast 50 and a pancake 40 are easy to make. I am sure some one can explain. The change to apsc didn't magically make it easier / cheaper to make a fast 28 or 35.

For DSLRs they are very easy because they are near the flange distance - a simple symmetrical design will work wonders.
Interestingly, large format lenses aren't particularly large (though they are slower for sure).

[ProfessorBuzz]

(...why are folk so enamored of difficult to focus lenses and photos with no discernible point of focus? )

Brilliant question that cuts right to the heart of the matter. Glad you said it.

[Belnan]

Brilliant question that cuts right to the heart of the matter. Glad you said it.

I guess people like the flexibility of getting to choose how much depth of field they want. Full Frame gives you more freedom to do that, and to top it off defraction isnt as big of an issue (depending on pixel size) so your smaller aperature will look sharper too on FF.

[Wasp]

35mm f1.4 was traditionally larger than 50mm f1.4 partly because on DSLR cameras these are retrofocal. Making massive lenses at 33mm f1.0 seems like a way to build arm strength!

A 33mm f1.0 would be very hard to focus and large.

Such a thing has just been launched. In fact it is one sixth of a stop faster than f/1.0.

It is not that big or expensive. It is 83mm (3.3") long, 72mm (2.8") in diameter and weighs 590g (1.3lbs) and sells for $499.

Hard to focus? It is manual focus and has roughly the same angle of view and DOF as a 50mm f/1.4 on FF. Tricky but not impossible.

No K (or any DSLR) mount version, though. Mirrorless only.




Venus Optics launches ultra-fast Laowa ?Argus? 33mm F0.95 CF APO lens for APS-C camera systems: Digital Photography Review

[swanlefitte]

The 50 1.2 has 0.25m dof at 3m, the 85 1.4 has 0.10m, and the 135 f1.8 has 0.05m.
As you take a longer lens you also isolate your subject from the background. This makes sense to me. If I want to isolate my subject why add more background just to blur it out? I suppose for a minimalist, or negative space composition that works but it is also niche.

[stevebrot]

For DSLRs they are very easy because they are near the flange distance - a simple symmetrical design will work wonders.

Strangely enough, most fast 50's for SLRs are retrofocus.


Steve

[stevebrot]

That lens will deliver ultra-thin DOF similar to a 50mm f:1.4 on 35mm/FF.

I would say probably a bit thinner...closer to f/1.1.


Steve

[DWS1]

I use aps-c and do not feel as if I am missing anything, I can get narrow enough DOF to suit my needs without a ridiculously expensive lens. But maybe some people do.

I'm right there with you.

[UncleVanya]

Such a thing has just been launched. In fact it is one sixth of a stop faster than f/1.0.

It is not that big or expensive. It is 83mm (3.3") long, 72mm (2.8") in diameter and weighs 590g (1.3lbs) and sells for $499.

Hard to focus? It is manual focus and has roughly the same angle of view and DOF as a 50mm f/1.4 on FF. Tricky but not impossible.

No K (or any DSLR) mount version, though. Mirrorless only.




Venus Optics launches ultra-fast Laowa ?Argus? 33mm F0.95 CF APO lens for APS-C camera systems: Digital Photography Review

Right. Note that as you point out it is not for dslr systems which I had pointed out adds size. Also we don’t yet know image quality, but my money is on it being ok but not edge to edge sharp wide open. A fast 33 that has seriously sharp edge to edge like the dfa 50 offers is more what I was thinking.

But you are correct and it was a good catch.

[jslifoaw]

Medium format lenses were capable of shallow depth of field at normal and wide angles comparable to 35mm format. For the Pentax 6x7, examples include the 45/4, 55/4, 75/2.8, 105/2.4, etc where you can divide the focal length and f numbers by 2 resulting in 35mm equivalent lenses in the f1.2-2 range for ultra wide to normal. Unfortunately none of these are very wide on Pentax digital medium format and similar angles of view are possible on 35mm with larger apertures.

35mm format has had so much investment and innovation such as mirrorless that very fast and high quality lenses exist in wide ranges of focal lengths (e.g. modern AF lenses at f1.2 from 85mm down to 35mm, f1.4 from 105mm down to 20mm, f1.8 from 135mm down to 14mm). It gets harder and harder to keep the aperture for wide angles comparably sized (which determines depth of field) as the format shrinks because of the required f numbers. For telephoto lenses, other constraints such as front element size level the playing field.

For large format you can also use tilt to control DOF which requires special lenses or adapters for smaller more common formats.

[Henrico]

You have a great selection of lenses....but you didn't actually answer my question

Haha, right.. No I would not spent that much for one lens. During the years I collect a lot of legacy glass from Marketplace from 14 mm - 400 mm, all together these cost less than the DFA 85 mm new.

I understand it might be difficult to develop an ultra bright DA 33 mm producing similar DOF like a 1.4/50 does on FF. The FF flange distance of the K-mount is not very helpful for that. But for MILC it shouldn't be that difficult. For one or more reasons it is not very common.

For 645 such lenses get very bulky and expensive. But they seam to exist as someone did post here.

Anyway a lot of response here, thnx guys!

[pschlute]

the more reach the lens has in relation to the aperture the more shallow dof you will get. the 85.1/4 (sic) is waay shallower to the 50/1.4 in my eyes.

That holds true when the camera to subject distant is constant, the 85mm 1.4 has about a third of the DOF as a 50mm 1.4

But not if the subject size is kept constant by moving further away with the longer lens. If I want to take a head and shoulder portrait and fill the frame, both lenses will produce the same DOF