Exif is intact, FWIW (including the lens info )
Camera Maker: Canon
Camera Model: Canon EOS 7D
Lens: EF100-400mm f/4.5-5.6L IS USM
Image Date: 2015-12-24 19:14:56 +0000
Focal Length: 160mm
Aperture: ƒ/7.1
Exposure Time: 0.067 s (1/15)
ISO equiv: 250
Exposure Bias: none
Metering Mode: Spot
Exposure: Manual
Exposure Mode: Manual
White Balance: Manual
Flash Fired: Yes (Auto, return light detected)
Orientation: Normal
Color Space: Adobe RGB (199
GPS Coordinate: undefined, undefined
Creator: Mario Cea Sanchez
Copyright: Todos los derechos reservados
Caption: Photographed using the technique of high speed with artificial light.
Made in a natural pond frequented every day by the bird.
I used several units of flash, synchronized to second curtain and a continuous light is used to capture the wake
The photograph was taken in Spain
Software: Adobe Photoshop CC 2015 (Windows)

Yes great capture. Better not say you shot it, it might fire back! It looks threatening.
Yes, seems the K-1 has revived the Pentax brand... at last. Quite deservedly.

I'd expect that to happen with any teleconverter given the loss of light transmission.

From Ricoh's website regarding the K-50.:

Changes to V1.10
Corresponded to [KAF4 lens mount] that is equipped with an electromagnetic diaphragm control system.
Enable new lens HD PENTAX-DA 55-300mmF4.5-6.3ED PLM WR RE to shoot stable by updating firmware.
Improved stability for general performance.

The update is here: http://www.ricoh-imaging.co.jp/english/support/digital/k-50_s.html

Why not daylight with a reflector is it helps?? By a window perhaps?

Thought it must be!

I agree, it's a well captured portrait. Great.

Which version would that be?

If it was important to them some used data-backs which could either date stamp the film or record exposure details. Others kept a notebook. They'll be some photographers who are not even aware the information exists in the form it does now, for others it is necessary for them to have it one way or another.
I'm still puzzled why you're worrying about something you say is not important to you, or is more relevant to you than what you're letting on?

I'd have thought the Q would be the easiest for your project. Big P might require some focus stacking which would be a bit of a faff!

It works with SDM lenses, but unlike the new Pentax one it doesn't adjust the reported focal length, however it doesn't cost the same either! As TCs go these are one of the better ones.