The kit lens does f/40

asp1880 · 06-17-2013, 03:07 AM

f/40 is quite rare for 35mm DSLR lenses. Why would you ever want f/40?

Because you can get 1/10 shutter speeds without filters in full daylight sun!

And you can see all your sensor dust clearly at the same time. Wow do I have a lot of sensor dust.

Regards,
--Anders.

**Ash** · 06-17-2013, 04:02 AM

Even f/40 can have insufficient DoF at 55mm when shooting some landscape scenes. At that aperture, the kit lens does suffer from a lot of diffraction and poor contrast.

**Aristophanes** · 06-17-2013, 05:39 AM

Are those birds or dust?

Eulogy · 06-17-2013, 06:17 AM

Originally posted by Ash

Even f/40 can have insufficient DoF at 55mm when shooting some landscape scenes. At that aperture, the kit lens does suffer from a lot of diffraction and poor contrast.

So about the same result as using a China made ND filter.

Anvh · 06-17-2013, 06:21 AM

Originally posted by Eulogy

So about the same result as using a China made ND filter.

You can call it lomo maybe?

Na Horuk · 06-17-2013, 06:22 AM

Ha, yeah. But the result isnt as bad as I thought it would be. Just clone out the dust, lower the clarity, incrfease sharpness and youre good

Racer X 69 · 06-17-2013, 07:29 AM

Originally posted by Aristophanes

Are those birds or dust?

I had to read the original post a second time to see it, but yes, the OP says it is dust.

Originally posted by asp1880

And you can see all your sensor dust clearly at the same time. Wow do I have a lot of sensor dust.

kh1234567890 · 06-17-2013, 09:22 AM

Originally posted by Ash

Even f/40 can have insufficient DoF at 55mm when shooting some landscape scenes. At that aperture, the kit lens does suffer from a lot of diffraction and poor contrast.

Rubbish.

wombat2go · 06-17-2013, 10:01 AM

The "fence test" with the original SMC Pentax-DA 18~55mm AL on the K-01. It is quicker than trying to put into words the fidelity across the plane at each setting
In this link are 6 camera jpgs, full screen button is bottom right.
18_f3.5, 18_f8, 18_f22
55_f5.6, 55_f8, 55_f40

https://www.box.com/s/d3whwi53hgyff7k4ocng

carrrlangas · 06-17-2013, 11:53 AM

I´ve used it when trying to get the sun in the frame and light the subject ith the on board flash (fill flash). f/40 allowed for 1/180sec shutter speed which is maximum sync speed for pentax.

Anvh · 06-17-2013, 01:19 PM

Originally posted by Ash

Even f/40 can have insufficient DoF at 55mm when shooting some landscape scenes. At that aperture, the kit lens does suffer from a lot of diffraction and poor contrast.

With those settings you can get everything in focus between 2 meter and the horizon.
I've no idea what kind of landscape you've in mind?

scratchpaddy · 06-17-2013, 01:57 PM

Originally posted by Anvh

I've no idea what kind of landscape you've in mind?

Something like this?

My mom took that picture with her $80 P&S, hence the huge DOF.

Just saying, there's a place for everything, no matter how ridiculous it sounds.

**Ash** · 06-17-2013, 02:16 PM

That's right. Some P&S cameras have f/64 and above, making landscapes with DoF from <1m to infinity a possibility. It would be useful in the setting of landscapes with for example lush green grass foreground with a background of mountains in the distance. I don't think I've personally desired that DoF much in scenes, but I do have a wide angle zoom that at 12mm and f/22 can give me very deep DoF when I need it.

In any case, I've seen and compared what the f/40 kit lens can do compared to say the Tamron 28-75 at 50mm and f/22, and even there I can see the difference in contrast and sharpness, let alone the results at f/8.

Anvh · 06-17-2013, 03:01 PM

thanks for the example XD

Cannikin · 06-17-2013, 03:34 PM

If you really need that crazy huge DOF, you're probably better off shooting with a wider angle lens and cropping than shooting at f/40. Chances are you'll be losing less real resolution by cropping than you will from diffraction at that small an aperture.

06-17-2013, 03:07 AM	#1
asp1880 Veteran Member Join Date: Jul 2010 Location: Lyngby, Copenhagen Photos: Albums Posts: 742	The kit lens does f/40 f/40 is quite rare for 35mm DSLR lenses. Why would you ever want f/40? Because you can get 1/10 shutter speeds without filters in full daylight sun! And you can see all your sensor dust clearly at the same time. Wow do I have a lot of sensor dust. Regards, --Anders.

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06-17-2013, 04:02 AM	#2
Ash Loyal Site Supporter Join Date: Mar 2007 Location: Toowoomba, Queensland Photos: Gallery \| Albums Posts: 23,920	Even f/40 can have insufficient DoF at 55mm when shooting some landscape scenes. At that aperture, the kit lens does suffer from a lot of diffraction and poor contrast.

06-17-2013, 05:39 AM	#3
Aristophanes Site Supporter Join Date: Jul 2008 Location: Rankin Inlet, Nunavut Photos: Albums Posts: 3,948	Are those birds or dust?

06-17-2013, 06:17 AM	#4
Eulogy Veteran Member Join Date: Feb 2012 Location: Fredericton, New Brunswick Photos: Gallery Posts: 632	Originally posted by Ash Even f/40 can have insufficient DoF at 55mm when shooting some landscape scenes. At that aperture, the kit lens does suffer from a lot of diffraction and poor contrast. So about the same result as using a China made ND filter.

06-17-2013, 06:21 AM	#5
Anvh Veteran Member Join Date: Sep 2011 Posts: 4,616	Originally posted by Eulogy So about the same result as using a China made ND filter. You can call it lomo maybe?

06-17-2013, 06:22 AM	#6
Na Horuk Veteran Member Join Date: Feb 2012 Location: Slovenia, probably Photos: Gallery \| Albums Posts: 11,186	Ha, yeah. But the result isnt as bad as I thought it would be. Just clone out the dust, lower the clarity, incrfease sharpness and youre good

06-17-2013, 07:29 AM	#7
Racer X 69 Moderator Man With A Camera Join Date: Jun 2010 Location: The Great Pacific Northwet, in the Land Between Canada and Mexico Photos: Gallery \| Albums Posts: 28,068	Originally posted by Aristophanes Are those birds or dust? I had to read the original post a second time to see it, but yes, the OP says it is dust. Originally posted by asp1880 And you can see all your sensor dust clearly at the same time. Wow do I have a lot of sensor dust.

06-17-2013, 09:22 AM	#8
kh1234567890 Veteran Member Join Date: Sep 2010 Location: Manchester, UK Photos: Gallery Posts: 2,653	Originally posted by Ash Even f/40 can have insufficient DoF at 55mm when shooting some landscape scenes. At that aperture, the kit lens does suffer from a lot of diffraction and poor contrast. Rubbish.

06-17-2013, 10:01 AM	#9
wombat2go Veteran Member Join Date: Jan 2010 Location: Michigan Photos: Gallery Posts: 2,207	The "fence test" with the original SMC Pentax-DA 18~55mm AL on the K-01. It is quicker than trying to put into words the fidelity across the plane at each setting In this link are 6 camera jpgs, full screen button is bottom right. 18_f3.5, 18_f8, 18_f22 55_f5.6, 55_f8, 55_f40 https://www.box.com/s/d3whwi53hgyff7k4ocng

06-17-2013, 11:53 AM	#10
carrrlangas Veteran Member Join Date: Mar 2012 Location: Joensuu (Finland) Photos: Gallery Posts: 1,761	I´ve used it when trying to get the sun in the frame and light the subject ith the on board flash (fill flash). f/40 allowed for 1/180sec shutter speed which is maximum sync speed for pentax.

06-17-2013, 01:19 PM	#11
Anvh Veteran Member Join Date: Sep 2011 Posts: 4,616	Originally posted by Ash Even f/40 can have insufficient DoF at 55mm when shooting some landscape scenes. At that aperture, the kit lens does suffer from a lot of diffraction and poor contrast. With those settings you can get everything in focus between 2 meter and the horizon. I've no idea what kind of landscape you've in mind?

06-17-2013, 01:57 PM	#12
scratchpaddy Pentaxian Join Date: Feb 2013 Location: Phoenix Posts: 3,361	Originally posted by Anvh I've no idea what kind of landscape you've in mind? Something like this? My mom took that picture with her $80 P&S, hence the huge DOF. Just saying, there's a place for everything, no matter how ridiculous it sounds.

06-17-2013, 02:16 PM	#13
Ash Loyal Site Supporter Join Date: Mar 2007 Location: Toowoomba, Queensland Photos: Gallery \| Albums Posts: 23,920	That's right. Some P&S cameras have f/64 and above, making landscapes with DoF from <1m to infinity a possibility. It would be useful in the setting of landscapes with for example lush green grass foreground with a background of mountains in the distance. I don't think I've personally desired that DoF much in scenes, but I do have a wide angle zoom that at 12mm and f/22 can give me very deep DoF when I need it. In any case, I've seen and compared what the f/40 kit lens can do compared to say the Tamron 28-75 at 50mm and f/22, and even there I can see the difference in contrast and sharpness, let alone the results at f/8.

06-17-2013, 03:01 PM	#14
Anvh Veteran Member Join Date: Sep 2011 Posts: 4,616	thanks for the example XD

06-17-2013, 03:34 PM	#15
Cannikin Veteran Member Join Date: Mar 2010 Location: SW Washington Posts: 833	If you really need that crazy huge DOF, you're probably better off shooting with a wider angle lens and cropping than shooting at f/40. Chances are you'll be losing less real resolution by cropping than you will from diffraction at that small an aperture.