The challenge of the new Pentaprism

**grahame** · 06-21-2021, 03:11 PM

Originally posted by hongman

would not mind the option or availability of a hybrid finder like Fuji too..!

fuji's hybrid viewfinder is good for fixed lens only, such as X100 serial. It does not work well X-PRO, because the optical viewfinder does not zoom with the lens.

I think the real "hybrid VF" should be overlay an LCD screen on the path of OVF. There is a "clear TV" that is clear and transparent when power is off. EVF cuts in only when it is powered on, otherwise it only shows focus point or other information.

Smolk · 06-25-2021, 05:08 AM - **1 Like**

Originally posted by house

I hope they will innovate the optical ovf to provide better manual focus.

That's certainly what they did with the K-3 III. In recent years, my eyesight has been an issue, but with the K-3 III I have no problem doing MF.
(I have been prone to mistaking a MF lens for an AF lens and wondering why it didn't focus...)

JPT · 06-25-2021, 07:43 AM - **1 Like**

The idea of a hybrid viewfinder sounds cool, but I wouldn't trade any OVF brightness for it. Ultimately, you buy a DSLR for the OVF experience, so that should be the priority. As far as I know, a hybrid viewfinder is possible now, but it would involve losing some of the light in the OVF, which is why neither Canon, Nikon or Pentax launched a camera like that despite having patents on it.

deus ursus · 06-25-2021, 08:40 AM

But if it was possible to make some sort of split prism overlay for use with manual lenses, I'd be all for it.

reh321 · 06-25-2021, 08:48 AM

Originally posted by deus ursus

But if it was possible to make some sort of split prism overlay for use with manual lenses, I'd be all for it.

Pentax has already made the K-3iii easier to use with old lenses, so I would certainly expect them to be considering possibilities to make focusing easier if the cost in usability is not too high.

Kunzite · 06-25-2021, 10:22 AM

Originally posted by JPT

The idea of a hybrid viewfinder sounds cool, but I wouldn't trade any OVF brightness for it. Ultimately, you buy a DSLR for the OVF experience, so that should be the priority. As far as I know, a hybrid viewfinder is possible now, but it would involve losing some of the light in the OVF, which is why neither Canon, Nikon or Pentax launched a camera like that despite having patents on it.

Right; the worst move IMO would be to compromise the OVF.
Of course, some of these patents don't require a hybrid viewfinder. If the hybrid viewfinder is too problematic* I'd rather see an OVF only "evolved DSLR".

* Fujifilm combines an EVF with a tunnel type viewfinder, thus very different than what Pentax would have to do. Which means they had to solve different challenges.

**mlt** · 06-26-2021, 12:40 PM

Originally posted by Kunzite

Right; the worst move IMO would be to compromise the OVF.
Of course, some of these patents don't require a hybrid viewfinder. If the hybrid viewfinder is too problematic* I'd rather see an OVF only "evolved DSLR".

* Fujifilm combines an EVF with a tunnel type viewfinder, thus very different than what Pentax would have to do. Which means they had to solve different challenges.

A transparent focus peaking overlay would be nice to see added to the optical viewfinder

reh321 · 06-27-2021, 01:40 PM

Originally posted by mlt

A transparent focus peaking overlay would be nice to see added to the optical viewfinder

What kind of 'overlay' do you envision??

**mlt** · 06-27-2021, 02:43 PM

Originally posted by reh321

What kind of 'overlay' do you envision??

Just a layer in the finder to show flashing focus peaking outlines. I would think this would require a bit of a cpu upgrade to process the edge detection along with the additional finder addition so I don’t expect this to be a firmware upgrade. More or less just wishful dreaming

**grahame** · 06-27-2021, 05:00 PM

Originally posted by mlt

Just a layer in the finder to show flashing focus peaking outlines

It requires a complete redesign of the camera, because a regular SLR camera does not have an image sensor on the light path to OVF, and the main CMOS is behind the mirror and shutter and does not get any light until shutter releases. So the camera does not have any focus peaking information.

**mlt** · 06-27-2021, 07:10 PM

Originally posted by grahame

It requires a complete redesign of the camera, because a regular SLR camera does not have an image sensor on the light path to OVF, and the main CMOS is behind the mirror and shutter and does not get any light until shutter releases. So the camera does not have any focus peaking information.

I think that it is do-able. If the k3iii can use the iRGB meter sensor for basic pattern recognition, then increasing the iRGB sensor pixel count to around 1 to 2 million pixels could provide the necessary edge detection capability

Wheatfield · 06-27-2021, 07:17 PM - **1 Like**

Originally posted by mtkeller

Has anyone figured out how to show off the K-3iii OVF to non-Pentaxians yet? I've handed my camera to a few users of other brands, but it's been hard to get them to really appreciate the difference. Pentax deserves a lot of credit for developing this wonderful pentaprism and viewfinder, but I'm not sure they're going to get all the accolades they deserve.

Buy a used Canon Rebel and then you have a hands on comparison. .

**mlt** · 06-27-2021, 07:53 PM

Originally posted by Wheatfield

Buy a used Canon Rebel and then you have a hands on comparison. .

Unless the other body and the k3iii have the same lens attached, they probably won’t say they can notice any difference. Even more fun is to ask them if their other brand of dslr can recognize objects to focus on when not in live view mode

Wheatfield · 06-27-2021, 08:52 PM - **2 Likes**

Originally posted by mlt

Unless the other body and the k3iii have the same lens attached, they probably won’t say they can notice any difference. Even more fun is to ask them if their other brand of dslr can recognize objects to focus on when not in live view mode

If a person can't see the difference between a Rebel viewfinder and a K3III viewfinder, they need to have their driver's license pulled, they can't see well enough to drive. I can't believe how bad those viewfinders are, and people were willing to spend money on them.

**grahame** · 06-27-2021, 09:10 PM

Originally posted by mlt

I think that it is do-able. If the k3iii can use the iRGB meter sensor for basic pattern recognition, then increasing the iRGB sensor pixel count to around 1 to 2 million pixels could provide the necessary edge detection capability

It might be a solution. But I am afraid the meter sensor does not see color, so the contrasty edge for peaking must be readable in BW pattern.
I am not a fan of focus peaking alone. I never find it to be accurate enough for fast lenses. On mirror-less cameras, I always use focus amplification + peaking for MF. So for me, I prefer a hybrid finder that has the image from CMOS projected to it. So if you need EVF, simply lift the mirror and you use it as a mirror-less.

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06-21-2021, 03:11 PM	#121
grahame Loyal Site Supporter Join Date: Aug 2011 Photos: Albums Posts: 2,041	Originally posted by hongman would not mind the option or availability of a hybrid finder like Fuji too..! fuji's hybrid viewfinder is good for fixed lens only, such as X100 serial. It does not work well X-PRO, because the optical viewfinder does not zoom with the lens. I think the real "hybrid VF" should be overlay an LCD screen on the path of OVF. There is a "clear TV" that is clear and transparent when power is off. EVF cuts in only when it is powered on, otherwise it only shows focus point or other information.

06-25-2021, 05:08 AM - 1 Like	#122
Smolk Pentaxian Join Date: Feb 2010 Location: Eerbeek Photos: Gallery \| Albums Posts: 1,856	Originally posted by house I hope they will innovate the optical ovf to provide better manual focus. That's certainly what they did with the K-3 III. In recent years, my eyesight has been an issue, but with the K-3 III I have no problem doing MF. (I have been prone to mistaking a MF lens for an AF lens and wondering why it didn't focus...)

06-25-2021, 07:43 AM - 1 Like	#123
JPT Pentaxian Join Date: Jan 2012 Location: Tokyo Photos: Gallery Posts: 2,821	The idea of a hybrid viewfinder sounds cool, but I wouldn't trade any OVF brightness for it. Ultimately, you buy a DSLR for the OVF experience, so that should be the priority. As far as I know, a hybrid viewfinder is possible now, but it would involve losing some of the light in the OVF, which is why neither Canon, Nikon or Pentax launched a camera like that despite having patents on it.

06-25-2021, 08:40 AM	#124
deus ursus Pentaxian Join Date: Nov 2012 Location: Stårheim, Norway Posts: 658	But if it was possible to make some sort of split prism overlay for use with manual lenses, I'd be all for it.

06-25-2021, 08:48 AM	#125
reh321 Pentaxian Join Date: Nov 2014 Location: South Bend, IN, USA Photos: Gallery \| Albums Posts: 23,175	Originally posted by deus ursus But if it was possible to make some sort of split prism overlay for use with manual lenses, I'd be all for it. Pentax has already made the K-3iii easier to use with old lenses, so I would certainly expect them to be considering possibilities to make focusing easier if the cost in usability is not too high.

06-25-2021, 10:22 AM	#126
Kunzite Pentaxian Join Date: Apr 2007 Location: Romania Posts: 15,132	Originally posted by JPT The idea of a hybrid viewfinder sounds cool, but I wouldn't trade any OVF brightness for it. Ultimately, you buy a DSLR for the OVF experience, so that should be the priority. As far as I know, a hybrid viewfinder is possible now, but it would involve losing some of the light in the OVF, which is why neither Canon, Nikon or Pentax launched a camera like that despite having patents on it. Right; the worst move IMO would be to compromise the OVF. Of course, some of these patents don't require a hybrid viewfinder. If the hybrid viewfinder is too problematic* I'd rather see an OVF only "evolved DSLR". * Fujifilm combines an EVF with a tunnel type viewfinder, thus very different than what Pentax would have to do. Which means they had to solve different challenges.

06-26-2021, 12:40 PM	#127
mlt Site Supporter Join Date: Dec 2007 Posts: 1,159	Originally posted by Kunzite Right; the worst move IMO would be to compromise the OVF. Of course, some of these patents don't require a hybrid viewfinder. If the hybrid viewfinder is too problematic* I'd rather see an OVF only "evolved DSLR". * Fujifilm combines an EVF with a tunnel type viewfinder, thus very different than what Pentax would have to do. Which means they had to solve different challenges. A transparent focus peaking overlay would be nice to see added to the optical viewfinder

06-27-2021, 01:40 PM	#128
reh321 Pentaxian Join Date: Nov 2014 Location: South Bend, IN, USA Photos: Gallery \| Albums Posts: 23,175	Originally posted by mlt A transparent focus peaking overlay would be nice to see added to the optical viewfinder What kind of 'overlay' do you envision??

06-27-2021, 02:43 PM	#129
mlt Site Supporter Join Date: Dec 2007 Posts: 1,159	Originally posted by reh321 What kind of 'overlay' do you envision?? Just a layer in the finder to show flashing focus peaking outlines. I would think this would require a bit of a cpu upgrade to process the edge detection along with the additional finder addition so I don’t expect this to be a firmware upgrade. More or less just wishful dreaming

06-27-2021, 05:00 PM	#130
grahame Loyal Site Supporter Join Date: Aug 2011 Photos: Albums Posts: 2,041	Originally posted by mlt Just a layer in the finder to show flashing focus peaking outlines It requires a complete redesign of the camera, because a regular SLR camera does not have an image sensor on the light path to OVF, and the main CMOS is behind the mirror and shutter and does not get any light until shutter releases. So the camera does not have any focus peaking information.

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06-27-2021, 07:10 PM	#131
mlt Site Supporter Join Date: Dec 2007 Posts: 1,159	Originally posted by grahame It requires a complete redesign of the camera, because a regular SLR camera does not have an image sensor on the light path to OVF, and the main CMOS is behind the mirror and shutter and does not get any light until shutter releases. So the camera does not have any focus peaking information. I think that it is do-able. If the k3iii can use the iRGB meter sensor for basic pattern recognition, then increasing the iRGB sensor pixel count to around 1 to 2 million pixels could provide the necessary edge detection capability

06-27-2021, 07:17 PM - 1 Like	#132
Wheatfield Moderator Join Date: Apr 2008 Location: The wheatfields of Canada Posts: 15,975	Originally posted by mtkeller Has anyone figured out how to show off the K-3iii OVF to non-Pentaxians yet? I've handed my camera to a few users of other brands, but it's been hard to get them to really appreciate the difference. Pentax deserves a lot of credit for developing this wonderful pentaprism and viewfinder, but I'm not sure they're going to get all the accolades they deserve. Buy a used Canon Rebel and then you have a hands on comparison. .

06-27-2021, 07:53 PM	#133
mlt Site Supporter Join Date: Dec 2007 Posts: 1,159	Originally posted by Wheatfield Buy a used Canon Rebel and then you have a hands on comparison. . Unless the other body and the k3iii have the same lens attached, they probably won’t say they can notice any difference. Even more fun is to ask them if their other brand of dslr can recognize objects to focus on when not in live view mode

06-27-2021, 08:52 PM - 2 Likes	#134
Wheatfield Moderator Join Date: Apr 2008 Location: The wheatfields of Canada Posts: 15,975	Originally posted by mlt Unless the other body and the k3iii have the same lens attached, they probably won’t say they can notice any difference. Even more fun is to ask them if their other brand of dslr can recognize objects to focus on when not in live view mode If a person can't see the difference between a Rebel viewfinder and a K3III viewfinder, they need to have their driver's license pulled, they can't see well enough to drive. I can't believe how bad those viewfinders are, and people were willing to spend money on them.

06-27-2021, 09:10 PM	#135
grahame Loyal Site Supporter Join Date: Aug 2011 Photos: Albums Posts: 2,041	Originally posted by mlt I think that it is do-able. If the k3iii can use the iRGB meter sensor for basic pattern recognition, then increasing the iRGB sensor pixel count to around 1 to 2 million pixels could provide the necessary edge detection capability It might be a solution. But I am afraid the meter sensor does not see color, so the contrasty edge for peaking must be readable in BW pattern. I am not a fan of focus peaking alone. I never find it to be accurate enough for fast lenses. On mirror-less cameras, I always use focus amplification + peaking for MF. So for me, I prefer a hybrid finder that has the image from CMOS projected to it. So if you need EVF, simply lift the mirror and you use it as a mirror-less.