How come 40mm is such an irrelevant focal length?

Started Apr 3, 2012 | Discussions
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Tom__Brown Senior Member • Posts: 1,344
How come 40mm is such an irrelevant focal length?

I love the DA40L technically, but it's a useless lens. I'll just pull it out to test with, every time I get another camera body. lol!

I've heard others here lament the focal length. Why is it so useless? I've got quite a few some shots with a DA16-45 that were taken at 45mm. 45mm isn't so far from 40.

Strange then the 40L feels like such a fish out of water in DX format. I'm sure it would be one of my favorite focal lengths if I was shooting full frame.

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ozdean
ozdean Forum Pro • Posts: 23,234
Re: How come 40mm is such an irrelevant focal length?

I reckon its the perfect prime for what the K01 was designed for; a touch longer than normal.
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John Cal
John Cal Regular Member • Posts: 307
Re: How come 40mm is such an irrelevant focal length?

It's a great lens for many things. This is the lens that made me buy into Pentax coming from Canon and Nikon.

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timo Veteran Member • Posts: 4,805
Re: How come 40mm is such an irrelevant focal length?

I have one, and it works well.

I would feel better about it if there were a modern 28mm. If you have a 40, then 35mm seems a bit redundant and vice versa. And yet the 21mm is too far away.

More and more I find myself packing the DA21, the M28/3.5 and the FA50/1.7. A bit ironic, having spent good money on the 40 and the cheapo DA35.
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Roland Karlsson Forum Pro • Posts: 25,176
The fish in the water barrel

This question reminds me of the fish in the water barrel riddle.

The riddle is something like this.

If you have a barrel full of water and put something in, e.g. a stone then some water from the barrel will spill over on the ground/floor.

The riddle is then - why does this not happen if you put a fish in the barrel?

Hard one - after some time some usually start to come up with explanations. Maybe the slime on the fish changes surface tension? Maybe the fish swallows the water? Maybe its magic?

But the answer is more simple than that. The riddle is false. There are no such effect.

And --- back to the 40 mm lens. You asked why it is not a good focal length. Yes?

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Ishpuini Veteran Member • Posts: 6,138
Re: How come 40mm is such an irrelevant focal length?

It comes down to personal preferences really.

I must agree that I never found 40mm an ideal focal length. But I never really liked 35mm on APS-C either. I always wanted slightly wider, hence the FA31 is better for me.

However, since I started increasingly shooting in the square format my preferences changed. Now I prefer the DA21/3.2 for a slightly wider standard, and my FA43 (close to 40mm) has become my mild tele of choice.

Wim

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sterretje Contributing Member • Posts: 840
Re: How come 40mm is such an irrelevant focal length?

Tom_ Brown wrote:

... Why is it so useless?

Simply because it's not your focal length. And neither mine. And for others, it's a perfect focal length.

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WimS

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Roland Karlsson Forum Pro • Posts: 25,176
Re: How come 40mm is such an irrelevant focal length?

sterretje wrote:

Simply because it's not your focal length. And neither mine. And for others, it's a perfect focal length.

OK - is it bad on both FF and APS-C?

In that case would 60 mm be bad on FF and 28 mm bad on APS-C. Is that so?

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LWW Contributing Member • Posts: 540
Re: How come 40mm is such an irrelevant focal length?

Stop moaning, get over it, chuck it in the bin, sell it. If you are not up to getting the most from it - your problem

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Roland Karlsson Forum Pro • Posts: 25,176
Re: How come 40mm is such an irrelevant focal length?

LWW wrote:

Stop moaning, get over it, chuck it in the bin, sell it. If you are not up to getting the most from it - your problem

Hmmmm .. evidently I was not clear enough.

I have no problems with 40 mm lens - neither on FF nor on APS-C.

I was just asking the guy that had. If it was the focal length or the FOV he did not like.

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snake_b Veteran Member • Posts: 4,680
Re: How come 40mm is such an irrelevant focal length?

The DA21 is nice, but too slow, really.

The X100 made it especially obvious that the DA21 is too slow, especially for the price that is being commanded for it.

LWW Contributing Member • Posts: 540
Re: How come 40mm is such an irrelevant focal length?

Apologies Roland,

Did not intend to direct my reply to you, more the original post. I can not understand how the focal length really is of any consequence once you are the owner. Just move the feet a bit. My DA40, hardly ever is used for a single frame, but as a optic for a vertical (portrait) stitched panorama - superb. both for image quality and perspective.
Just a matter of fit to purpose.

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13thBagel
13thBagel Senior Member • Posts: 1,140
Huh??

snake_b wrote:

The DA21 is nice, but too slow, really.

The X100 made it especially obvious that the DA21 is too slow, especially for the price that is being commanded for it.

You can compare a complex part to a system and expect to make a categorical judgment that's credible...? Kinda like comparing a MINI headlight to a Volkwagen...? OK, they're German products, but what's your point?

Help me understand... M

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snake_b Veteran Member • Posts: 4,680
Re: Huh??

Ok. The DA21 is a slow lens.

13thBagel wrote:

snake_b wrote:

The DA21 is nice, but too slow, really.

The X100 made it especially obvious that the DA21 is too slow, especially for the price that is being commanded for it.

You can compare a complex part to a system and expect to make a categorical judgment that's credible...? Kinda like comparing a MINI headlight to a Volkwagen...? OK, they're German products, but what's your point?

Help me understand... M

Paphios Regular Member • Posts: 395
Re: How come 40mm is such an irrelevant focal length?

For years in film photography a MicroNikkor 55mm was my main prime lens rather than the usual 50. For me the 40mm focal length on APS-C seems pretty natural

Matthew Miller
Matthew Miller Senior Member • Posts: 1,310
Re: Huh??

13thBagel wrote:

snake_b wrote:

The DA21 is nice, but too slow, really.

The X100 made it especially obvious that the DA21 is too slow, especially for the price that is being commanded for it.

You can compare a complex part to a system and expect to make a categorical judgment that's credible...? Kinda like comparing a MINI headlight to a Volkwagen...? OK, they're German products, but what's your point?

The X100 has a 23mm f/2 lens.

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Matthew Miller
Matthew Miller Senior Member • Posts: 1,310
I like it.

Roland Karlsson wrote:

But the answer is more simple than that. The riddle is false. There are no such effect.

Exactly. For me, it's very convenient; it's within the range of

"normal", but slightly narrow, tending to make composition more focused. And that same extra length makes it a bit nicer for portraits than a wider normal would be. Altogether, this means that it stays on my camera most of the time.

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mervis50 Regular Member • Posts: 214
Try it. You'll like it.

You're asking a question based on an opinion which is based on a fallacy. Yes, it's unusual compared to what we think is standard, but in and of itself, it's just another focal length. Just because it's not widely popular doesn't make it wrong or 'irrelevant.

It's really a marvelous piece of glass - a pleasant surprise. And only $150 as part of the K-01 kit. I'm finding it to be a very nice street lens. Brings you in a little closer when necessary; gives more focal separation between subject and background than a standard; mild foreshortening for portraits.

Don't diss this lens!
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Ari Aikomus
Ari Aikomus Veteran Member • Posts: 7,549
Yep, and 55mm Takumar...

Paphios wrote:

For years in film photography a MicroNikkor 55mm was my main prime lens rather than the usual 50. For me the 40mm focal length on APS-C seems pretty natural

I agree. 55-60mm is quite nice FF (fullframe) focal lenght range .

I use my old m42 Takumar 55/1.8 all the time with FF Canon 5D:

cheers,

Ari

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Photonom Regular Member • Posts: 133
Ari Question

Ari Aikomus wrote:

Paphios wrote:

For years in film photography a MicroNikkor 55mm was my main prime lens rather than the usual 50. For me the 40mm focal length on APS-C seems pretty natural

I agree. 55-60mm is quite nice FF (fullframe) focal lenght range .

I use my old m42 Takumar 55/1.8 all the time with FF Canon 5D:

Ari,

Do you have any problem with the mirror of the Canon 5d hitting the back of this lens or any other M42's you may have.

Thanks, Robert

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