Pentax camera body

[soldevilla]

Someone are here using a Pentax body with liveview in his microscope? I buyed a second hand one, but I have some doubts...

[lothman]

the only problem I am aware is that only a few Pentax models have electronic first curtain, so your model might suffer from vibrations / blurred pictures depending on your setup.

[Duke]

I use Pentax KP. It's a pain.
There is no software - unless you buy a CD (in 2021? Who even has CD-rom drive anymore?!) for 400$?
This is as ridiculous as it's outrageous!
It's been a year, and I'm still in a struggle to tether Pentax KP to my PC. There are some free apps like WiFi commander, PkTriggerCord, PentaxForums PentaxWifi + USB tether for PC, all of them produce terrible liveview resolution and compression artifacts - absolutely unusable, can't see anything and can't use liveview zoom (focus assist). Still can't use most of them because USB is in use for HDMI output and it doesn't work simultaneously with USB/PTP connection. Why would you combine everything into 1 usb port if it's not a hub-port and only slow USB2.0. OMG Pentax you do really try grinding my gears, don't you!
I managed to track down power supply, micro-usb MyDP->HDMI connector (Mobility DisplayPort is not MHL! - didn't know such thing even exists, no wonder - it's rare as hell) and programmable remote trigger, and HDMI capture card. Buying Pentax stuff is a real quest - and a hard one!
So I got liveview in 1080i from the HDMI capture card to PC using OBS, while surprisingly still able to control camera through Pentax ImageSync (from Android tablet - still need to figure how out to get Android emulator for my Linux PC), liveview stays on HDMI, while on tablet showing black screen - I'm almost 100% positive that it shouldn't work this way, it's a bug, but a good one, really only good thing about this camera. Still, no way to call live view zoom without touching the camera - most important feature feature for me.
Never did I ever had to deal with so much bullsh* to get the basic functionality of DSLR.
Lesson learned - wouldn't buy Pentax ever again.

[soldevilla]

I bought a second-hand pentax because I had the intuition that a camera without low-pass filters would work much sharper when shooting with closed apertures. In this matter, I am delighted. But when I use the liveview on an external screen with HDMI with my Canon, the image brightens and darkens as I change the exposure and the overlay histogram shows that change. With the pentax, it seems that somewhere there is something like an automatic gain that modifies the brightness of the image and the histogram, so that that information is totally useless. And yes, I am working with a fixed ISO, and totally in manual.

[Duke]

But when I use the liveview on an external screen with HDMI with my Canon, the image brightens and darkens as I change the exposure and the overlay histogram shows that change.

That's "exposure simulation" option in Canon. It's actually very limited in terms of exposure and amount of light on the sensor, on my Canon 500D limit is ~1/5 s.
On Pentax there is no such option - not that I'm aware of. There is way to work around it - you have to be in TAv (instead of M) mode and on some aperture settings it will work.
I personally, prefer to use green button in M mode, it automatically sets the exposure, then I move exposure 2 steps up to use full dynamic range of the sensor and get the best noise performance.