[Clinton]

just have a little tact and consider the situation others may be in before you gloat on about your decision whether to spend a measly 3k on another useless lens.

You know what? You're completely right! What were you thinking reading a thread about a really expensive and useless lens? Here's a much better one:

https://www.pentaxforums.com/forums/81-expired-listings/220345-sale-withdrawn...125-000-a.html

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Last edited by Clinton; 03-23-2016 at 08:38 PM.

[jpzk]

So Clinton ... Have you yet made a final decision on this fine piece of gear ?
Sorry if I haven't read all the previous posts ... just wondering.
I am very curious about this and looking forward to see some extreme DOF shots!!
Cheers!

[Clinton]

I still don't know what to do. It's a lot of cash.

[lmd91343]

I still don't know what to do. It's a lot of cash.

Do you need the money for something else?
Can it help make you happier?

[Rupert]

I'm not interested, but I do see lots of wildlife shooters here that spend more on long glass....some lots more. If it fits your passion, why not?

Money is much less important than satisfaction in your passion. I have lots of things I don't really need......and even more I don't deserve.

As long as no one gets hurt, no one suffers, no one is deprived....



Regards!

[Simen1]

I think this chart is more telling:
How much blur? - A visual background blur calculator

It's interesting to compare the subject isolation to the 400/2.8

Interessting link. Its really about three parameters: Aperture diameter, subject size, and background distance. If we keep the subject size constant and the background at infinity then its even easier. Then you will find that background blur is proportional to the aperture diameter. But taking portraits with 400/2,8 must be extremely impractical because of the distance between the camera and subject. When its possible to find lenses with the same aperture diameter with shorter focal length, the distance problem will decrease. Ideally a 200/1,4 would be better then a 400/2,8 because you get closer to the subject. And a 100/0,7 would be better still, even if the diameter is the same. But lenses like that doesn’t exist of course. In other words, the the Mitakon 135/1,4 is one of the most bokehlicious portrait lenses possible. If you like to be even closer, you wont get quite the same extreme bokeh blur with 85/1,2, but in a studio where the distance between the subject and the background is less then a few meters it will be almost the same.

I still don't know what to do. It's a lot of cash.

Its like a promising stock. You might end up selling it for a lot more then you bought it for. You will make a K-mount legend.

On the other hand, the reasonable less exciting choice (weight and price) will be the Mitakon 85/1,2 at 799$ or the even more budget friendly Samyang 85/1,4 (258$) or 135/2,0 (486$). The Pentax A* cost on average 2-4 times those prices.

[Nicolas06]

What the link show for the same subject size (framing):

- The perfect equivalence with the crop factor applied to focal length and apperture for blur, including the amount of background blur when subject size is kept constant whatever the background distance. So 50mm f/1.4 on APSC is perfectly equivalent on all account regarding deph of field and bokeh to 75mm f/2.1 (75=50*1.5; 2.1 = 1.4 * 1.5)
- That if only the sensor size changes but focal length and apperture don't change (and so shooting distance change to keep the same framing), the blur at infinite is the same but larger sensor get things blured faster.
- That if sensor size doesn't change, keeping the physical apperture the same width mean same blur at infinite (so 50mm f/1.4 = 100mm f/2.8 = 200mm f/5.6) but the blur goes faster with shorter focal length. This is logical: this mean you need to be more near to the subject to get the same framing.
- That if sensor size and relative apperture doesn't change, the longer the focal length, the more blur you get at all background distances (so 200mm f/1.4 get more blur than 100mm f/1.4 that get more than 50mm f/1.4).

[Clinton]

So...

I've received my 85/1.2. The exterior construction is built to kill zombies. It's really quite sharp considering what it is. The rear element has chip polish marks around the far outside edges. I don't expect this will change photo quality; but as an a trial, it's definitely convinced me that I shouldn't buy one of these.

[K-amps]

Leaving out the issue of trying to MF on a razor fine DoF, the issue of the Bokeh still exists... its a bit busy looking for me...

[Nicolas06]

So...

I've received my 85/1.2. The exterior construction is built to kill zombies. It's really quite sharp considering what it is. The rear element has chip polish marks around the far outside edges. I don't expect this will change photo quality; but as an a trial, it's definitely convinced me that I shouldn't buy one of these.

I didn't got it? You tried the 85mm f/1.2 from same manufacturer?

[Pål Jensen]

The lens seems utter pointless to me. It weights 3kg and cost $3000. it may have some use in some niche low light condition, but it is hard to see why you should not rather change to a camera with half a stop lower noise. It cannot be used at close portraits wide open, which was the main usage for 135mm portrait lenses, as the DOF is too thin. Any current 135mm lens will give you enough subject isolation for portraits anyway. Besides, background blur can be done in Photoshop.
Thin DOF is not the same as bokeh.....

There's probably a good reason for the number of 100 (and the deposits). They are lucky if they sell that many....