[Jorgario]

Focal length never changes

OK ...

[zzeitg]

just for fun... my daughter's "lego friends" kit and its bokeh
(FA* 28-70 wide open)

[hoopsontoast]

MZ-S / FA43

[hoopsontoast]

DA14

[k0og]

Here is a detail shot of our Valentine's dinner table setting. It was a nice evening!

Pentax-M 35mm f2.8, K100DS, ISO200, 1/10 sec., wide open.

(cross-posted from the M club)

-Joe-

[arne.oestlund]

Sensor size too. Sensor change the deph of field that also change the bokeh.

Just look at typical MF film pictures as opposed to say Q pictures.

And what is the focal length of a Q lense conpared to a MF lense?? As I stated in my previous post, bokeh depends on focal lenght and aperture. If you have a certain lense it projects the same image independent of sensor size, as long as the distance between lense and sensor are the same, as they are if you compare APS-C and FF sensors. Otherwise the infinity mark on the lense would not be the same.

[Nicolas06]

And what is the focal length of a Q lense conpared to a MF lense?? As I stated in my previous post, bokeh depends on focal lenght and aperture. If you have a certain lense it projects the same image independent of sensor size, as long as the distance between lense and sensor are the same, as they are if you compare APS-C and FF sensors. Otherwise the infinity mark on the lense would not be the same.

Deph of field also depend of viewing size and so framing. To keep the same deph of field comparison means that you'll print say all your Q image on 10"x15" and all your MF image on 60"x90" and if one day you buy an APSC sensor, you'll obviously print them at 31"x47"...

Also if there a full body portrait on the 645Z, there would just the shirt pocket on the Q picture.

Your hidden hypothesis is that magnification stay the same and viewing size and framing is proportionnal to sensor size. This allow you to say the deph of field doesn't change. But also mean you don't care of what picture you take at all.

My hidden hypothesis is that the framing is important, that as a photographer you have an objective like taking a headshoot or taking a wide landscape and that you'll display the picture the same independantly of the original sensor but more depending of the medium in use. If you look at a photo on Pentax forum with your mobile it will have the same size regardless if it was taken with MF or Q... And if you display it full screen on your 24" monitor it will be the same size again for MF or Q. If you decide to print it and put on a wall and decide for a 30"x45" you'll not change your idea to print 180"x270" because this time you used the 645Z instead of the Q.

I think my hidden hypothesis is more pragmatic than yours. But that's just me.

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Last edited by Nicolas06; 02-15-2015 at 11:33 AM.

[Prakticant]

Fotografia, portret, W #

[zman]

The bitterly cold weather has me trapped inside. Trying to get the feel of a newly acquired Meyer Optik Trioplan 100mm f2.8 lens. Took a few pics of some artificial flowers and one of my wife's statues. The bubble bokeh may not be to everyone's taste but I love it and is the sole reason I bought the lens.

[stubyles]

Seasonal bokeh of Roses with Auto-Tak 55mm F1.8 Zebra:





And one from a Fujinon 55mm F2.2 plastic fantastic:

[stubyles]

The bubble bokeh may not be to everyone's taste but I love it and is the sole reason I bought the lens.

Me too!
Love the last one

[paulh]

Sigma 17-70 DC macro on an *ist D (xposted):

[wolfhask]

Fa 50 1.4



DA 18-55 WR



Tamron 70-200 2.8



FA 80-200 2.8



DA 18-135 WR

[jgnfld]

For some reason these 2 weeds in a snowy field appeal to me--especially the contrast of in-focus and out-of-focus elements.

PENTAX DA 50 1.8

[peterjcb]

K series-50mm F1.2...gorgeous all metal lens, one of my Fav's....but not an easy lens to nail focus @ 1.2