Bokehliciousness-- Similar FOV vs sensor size

Simple question: Is the bokehliciousness of a 35 f/1.4 on crop act similar to a 50 f/1.4 on FF?

It's all in the whatever and whatever.

If you work out the right details you have more room in depth of field toward the narrow range (more background blur). But that can get overplayed unless you set out to shoot everything wide open and know how to actually control your "stuff".

Tony, what I meant is given the same/similar FOV and subject size in the frame, could they give similar looks?

I like the way the 50 looks on FF. Correct me if I'm wrong, but the 35 should provide me similar results on a 1.6x crop.

Staszek wrote in post #11858577
Simple question: Is the bokehliciousness of a 35 f/1.4 on crop act similar to a 50 f/1.4 on FF?

Since when did bokehliciousness become a word?

Simple answer for your question - go to a camera store and try it.

Simple.

neilwood32 wrote in post #11860010
Since when did bokehliciousness become a word?

Ever since Kai W started using it :P

Staszek wrote in post #11859717
Tony, what I meant is given the same/similar FOV and subject size in the frame, could they give similar looks?

I like the way the 50 looks on FF. Correct me if I'm wrong, but the 35 should provide me similar results on a 1.6x crop.

Well, if you open the aperture on the 35 on the crop wider than you use on the 50 and the full frame, then you can get a similar shallow depth of field, if that's what you are asking.

I meant shooting the two lenses on the different formats at the same aperture with same subject size.


I figured it out using a DOF and FOV calculator:

A 50mm on FF has a 46.8º diagonal FOV. With a subject distance at 12' it provides ~1'5" DOF at f/1.4.
A 35mm on 1.6x has a 42.2º diagonal FOV and 1'10" DOF at f/1.4 and 12'.

So this tells me that a 35 shot at f/1.4 will be very similar to a 50 shot at f/1.4 on FF, which is what I was looking for.

Staszek wrote in post #11866406
I meant shooting the two lenses on the different formats at the same aperture with same subject size.

I figured it out using a DOF and FOV calculator:

A 50mm on FF has a 46.8º diagonal FOV. With a subject distance at 12' it provides ~1'5" DOF at f/1.4.
A 35mm on 1.6x has a 42.2º diagonal FOV and 1'10" DOF at f/1.4 and 12'.

So this tells me that a 35 shot at f/1.4 will be very similar to a 50 shot at f/1.4 on FF, which is what I was looking for.

You have your figures wrong -- there is a pretty substantial difference between the 5D at 50mm and the crop at 35mm using the same aperture and distance to subject. Re-run your numbers!

Once I finished gagging over the use of "bokehliciousness," I was able to read your post and do the following quick anaylsis:

The similarity is there, but there are other things to consider as well.

Assuming an EOS 5D Mark II with an EF 50mm f/1.2L USM and an EOS 7D with an EF 35mm f/1.4L USM as the two camera/lens combinations, and assuming an aperture of f/2.8 at a focus distance of 3m for each exposure, with identical subjects, backgrounds, and subject-to-background distances:

The 5D/50mm has an AoV of 46.8° and a DoF of 2.72–3.34m.

The 7D/35mm has an AoV of 41.9° and a DoF of 2.66–3.44m.

These appear similar at first glance. One would think, therefore, that their bokehs would be virtually identical. However, this is not necessarily the case.

While both lenses have eight-bladed apertures, the 50mm has a circular aperture and the 35mm has a polygonal aperture. Therefore, the 50mm should, in theory, have a somewhat creamier bokeh.

Notice I didn't say better. Better is completely subjective.

In practice, there are even more things to consider. The amount of spherical aberration will affect the bokeh. Even slight variations can introduce significant differences. If the image is to be uncropped, then chromatic aberration at the image edges will cause the bokeh to vary over the field.

As I said, lots of things to consider. Also, since bokeh is very subjective, what I consider beautiful bokeh you may consider to be crap, and vice versa.

This is why bokeh is not a quantified value in lens specifications.

Your best bet is to take pictures using both camera/lens combinations and see for yourself.

Thanks 20. As I said before, I know they won't be identical. I'm just looking for similar characteristics.

Staszek wrote in post #11858577
Simple question: Is the bokehliciousness of a 35 f/1.4 on crop act similar to a 50 f/1.4 on FF?

No.

Bokeh is dependent on the physical size of the aperture rather than the f stop. Therefore a 35 mm f/1.4 (35/1.4 = 25 mm) on a crop will have similar bokehliciousness to a 50 f/2 (50/2 = 25mm) on a full frame.

You would need a 35 f/1.0 (on a crop) to get the bokehliciousness of a 50/1.4 (on FF).

Now that has been resolved, the word "bokehliciousness" is never again to be used by any sane person within this forum