[photoptimist]

The use of an extension tube causes light loss because you have increased the focal length of the lens without changing the diaphragm, so the focal ratio changes. The focal length is increased because the rays entering the lens at macro distances are not parallel but diverging. This divergence causes the focus to be pushed further back, requiring the use of a tube. The light loss has nothing to do with image circle.

It's two ways of looking at the same phenomenon. The total intensity of the light passing through the lens from the scene is controlled by the entrance pupil geometry, not by whether the scene elements are in focus or not. In uniform lighting conditions, three 18% gray cards at different unfocused foreground, in-focus mid-ground, and unfocused background distances will have the same intensity.

But the further away one moves the sensor/film from the lens, the greater the spread of the projected cone of collected light. The image circle certainly does grow with added extension and the fixed amount of light gathered by the lens is spread over that greater diameter (but obviously this effect says nothing about different lenses designed for different image circles). Double the lens-to-sensor distance = double the cone diameter = 1/4 the light intensity per unit area.

[btnapa]

Wow, just wow.

And we are still using 25 year old lenses on our Pentax 645z, and an OVF........

I don't know what to say, perhaps except for that my entire system will be going up for sale.

Damn.

I agree. Wow. A 645Z class image maker in a more compact body with more modern lenses with more to come.

We knew competition was coming but did not expect this one. Pentax better make a move or it might be a quick check-mate. Who knows what Sony and the rest of the bunch are up to. With the Fuji intro and already shipping Hassy, 645Z reign might be over.

[copland35]

Personally, I think it looks perfect. Every design decision seems to have come right out of my wish list. It definitely looks like a more serious tool than the Hasselblad. Will I buy one? No. It just doesn't fit into my personal photographic roadmap, and I don't feel compelled to own everything that I admire.

As for all the hype. . . "gamer changer!" "revolutionary!" Yeah, yeah, I've heard all that before. There was similar talk when the Sony Alpha A7 series debuted. It was a revolutionary game-changer, and all the other companies would have to scramble to get their own mirrorless full-frame cameras on the market. Except somehow that didn't happen. And I think the A7 series is doing OK, but even with a full court press by Sony's marketing, it hasn't really set the world on fire the way some imagined it would.

Sony suffers from a lack of professional infrastructure. The designs have often created problems with overheating. They have fantastic potential but to get close to Canon or, Nikon they will need to be beyond criticism, robust, perfectly made, designed and engineered and have true worldwide, all day, instant everyday professional back-up.

Sony have a way to go.

Fujifilm have a history of high end professional tools and have laid down a series of models that are attracting attention from serious professionals.

Pentax have done well and have the potential to do hugely better. Their problems are that they mainly want niche appeal. They have Image quality, robustness, value for money, outdoor field cameras.
The attention to detail needed to be as compelling as Fujifilm has been missing. I love picking up Pentaxes. Compare the Pentax SV with the Leica M3. Both were amazing. The SV was the better photographer's tool. It is such a zen statement. The reductionism it contains creates a platform for the superb Takumars and made the camera an extension of the photographer's body.
Pentax can do better. The key is in the K-01. Make that camera. Take away the stand off distance needed for dSLR lenses. Make optics that put the lenses close to the focal plane. An adaptor for DSLR lenses is all that is needed if you want legacy glass. The brand new lenses you could design can be ridiculously good if they are designed to be close to the sensor. Add a classy evf. The camera can have the cool K1 screen. A full frame sensor. This could be a supercapable studio and field camera especially with fast memory media. Give it wifi to link in bigger screens and allow wireless control. Pixel shift and sensor tilt and shift.
Pentax however, still needs the pro back-up infrastructure to be a serious contender. Fuji have overturned the whole professional market with their new medium format offering and, whilst there is a redrawing of the market as companies assess their responses, Ricoh/Pentax must get ready to lay out their professional stall with compelling products and services that change minds like Fujifilm have.

[itshimitis]

Sony suffers from a lack of professional infrastructure. The designs have often created problems with overheating. They have fantastic potential but to get close to Canon or, Nikon they will need to be beyond criticism, robust, perfectly made, designed and engineered and have true worldwide, all day, instant everyday professional back-up.

Sony have a way to go.

Fujifilm have a history of high end professional tools and have laid down a series of models that are attracting attention from serious professionals.

Pentax have done well and have the potential to do hugely better. Their problems are that they mainly want niche appeal. They have Image quality, robustness, value for money, outdoor field cameras.
The attention to detail needed to be as compelling as Fujifilm has been missing. I love picking up Pentaxes. Compare the Pentax SV with the Leica M3. Both were amazing. The SV was the better photographer's tool. It is such a zen statement. The reductionism it contains creates a platform for the superb Takumars and made the camera an extension of the photographer's body.
Pentax can do better. The key is in the K-01. Make that camera. Take away the stand off distance needed for dSLR lenses. Make optics that put the lenses close to the focal plane. An adaptor for DSLR lenses is all that is needed if you want legacy glass. The brand new lenses you could design can be ridiculously good if they are designed to be close to the sensor. Add a classy evf. The camera can have the cool K1 screen. A full frame sensor. This could be a supercapable studio and field camera especially with fast memory media. Give it wifi to link in bigger screens and allow wireless control. Pixel shift and sensor tilt and shift.
Pentax however, still needs the pro back-up infrastructure to be a serious contender. Fuji have overturned the whole professional market with their new medium format offering and, whilst there is a redrawing of the market as companies assess their responses, Ricoh/Pentax must get ready to lay out their professional stall with compelling products and services that change minds like Fujifilm have.

With respect, they won't have 'overturned' the whole professional market until a) we see real world results and b) they actually have all 6 of these lenses out, available and performing well.

[SylvainB]

I am still amazed by the amount of comments speaking about "game changer", "xx killer", "revolutionary", "superb quality", and giving market share projections.
Do you realize that you are talking about a fully working mock-up ?


There is nothing wrong about dreaming out loud, and projecting your wishes, but you haven't seen anything yet. You can be attracted to it, you can be highly curious, but you can't take it out to take pictures yet and confirm any of your dreams. So calm down... and send zillions of messages to Pentax to ask them to add more lenses to the roadmap, or to propose new improved concept of MF, and in general ask them to react to the new offerings being developped and announced !

[Tony Belding]

I am still amazed by the amount of comments speaking about "game changer", "xx killer", "revolutionary", "superb quality", and giving market share projections.
Do you realize that you are talking about a fully working mock-up ?

You do realize that "fully working mock-up" is a contradiction, right? I think the word you are looking for is prototype.

This camera looks like an overgrown X-T2, and Fujifilm have a well established track record with the X-T1 and associated lenses. I think those of us familiar with those cameras have a pretty good idea what to expect from the GFX 50S, unless Fuji inexplicably drop the ball and start messing up things they've been doing exceptionally well up to now.

[itshimitis]

You do realize that "fully working mock-up" is a contradiction, right? I think the word you are looking for is prototype.

This camera looks like an overgrown X-T2, and Fujifilm have a well established track record with the X-T1 and associated lenses. I think those of us familiar with those cameras have a pretty good idea what to expect from the GFX 50S, unless Fuji inexplicably drop the ball and start messing up things they've been doing exceptionally well up to now.

Have you perhaps considered that SylvainB's first language may not be English? How's your French? Mine is pretty rusty so I'm not going to tackle his English or else I might look like a fool.

[Rondec]

I am still amazed by the amount of comments speaking about "game changer", "xx killer", "revolutionary", "superb quality", and giving market share projections.
Do you realize that you are talking about a fully working mock-up ?


There is nothing wrong about dreaming out loud, and projecting your wishes, but you haven't seen anything yet. You can be attracted to it, you can be highly curious, but you can't take it out to take pictures yet and confirm any of your dreams. So calm down... and send zillions of messages to Pentax to ask them to add more lenses to the roadmap, or to propose new improved concept of MF, and in general ask them to react to the new offerings being developped and announced !

The problem I have with the term "game changer" is that we are talking about a tiny portion of the digital market and one that is increasingly crowded out by full frame cameras.

A big splash in a very small pond, maybe?

On the other hand, people shoot medium format for the glass and the look of the images and a different form factor camera probably won't change that a whole lot.

[Bluefin]

I moved to the 645z from Nikon D810 last month. I knew fall announcements were around the corner but I pulled the trigger anyway because the 645z exceeded my expectations for medium format.

It still does despite recent announcements from Fuji and Hasselblad.

I purchased a low shutter count 645z for $5,200 and bought 6 lenses. I'm blown away by the IQ and price for THE 645Z and used lenses!

The Fuji and Hasselblad announcements will drive 645 pricing down even further despite the fact that the 645z may well have a superior sensor.

So now everybody wins: Those who can't wait to get their hands on new technology and those who are happy with the 645z!

[butangmucat]

Any tech heads, is it likely we can put other lenses on this Fuji body? Or would the sensor be too close?

In theory, no. All you need is an adapter to extend the register to that of other lenses. Much like the K mount adapters for Sony and M43 MILCs.

[larkis]

Pentax still has a great product despite being super conservative as a company with some of the most garbage marketing tactics in the industry. The lenses all need to be brought up to a modern spec for sure. The new 35mm, the 90mm the 28-45mm are the benchmarks to hit at the minimum.
At the end of the day the form factor of the camera is great for shooting but horrible for lugging around if someone is doing landscape far away from a car. Something like the new Fuji can be taken into the back country for a week or more with room in the backpack for food and clothing and camping gear. For the type of shooting that I do, this is a game changer (as long as the batteries can go far). Despite all this, mirrorless cameras are not automatically better for everything than heavy SLR's, but they are better at some key things that can potentially appeal to many.

[Fenwoodian]

I agree. Wow. A 645Z class image maker in a more compact body with more modern lenses with more to come.

We knew competition was coming but did not expect this one. Pentax better make a move or it might be a quick check-mate. Who knows what Sony and the rest of the bunch are up to. With the Fuji intro and already shipping Hassy, 645Z reign might be over.

All Pentax needs to do is to put their phenomenal "pixel shift" feature on a MF camera and they'll leapfrog ahead of everybody!

[Kolor-Pikker]

Found an image comparing the size of the GFX to the D810, it's pretty small even compared to a DSLR!


https://m.facebook.com/albahturin/albums/187221141314590/

[btnapa]

Found an image comparing the size of the GFX to the D810, it's pretty small even compared to a DSLR!


Welcome to Facebook

That is small, really small for 645 sized sensor. Thanks for sharing.

---------- Post added 09-21-16 at 12:26 PM ----------

All Pentax needs to do is to put their phenomenal "pixel shift" feature on a MF camera and they'll leapfrog ahead of everybody!

Or better yet, come out with a 6x7 medium format with a full frame sensor in the 100+ MP range. They will own the market for a long time. I know this is pipe dreaming given the size of the market for MF cameras. I bet you if the volume was there to at least recover their investment in R&D, Pentax has plenty of know how to pull it off. After all the Fuji form factor is nothing but a modern version of 6x7 with mirrorless implementation.

As to your point on the PS on 645Z, I remember reading somewhere that they have tried to do it but they could not stop the sensor shaking fast enough to make it work. The problem is due to the fact that the sensor and the housing that hold it are too big and quite a bit heavier compared to the smaller DSLR format.

---------- Post added 09-21-16 at 12:29 PM ----------

I moved to the 645z from Nikon D810 last month. I knew fall announcements were around the corner but I pulled the trigger anyway because the 645z exceeded my expectations for medium format.

It still does despite recent announcements from Fuji and Hasselblad.

I purchased a low shutter count 645z for $5,200 and bought 6 lenses. I'm blown away by the IQ and price for THE 645Z and used lenses!

The Fuji and Hasselblad announcements will drive 645 pricing down even further despite the fact that the 645z may well have a superior sensor.

So now everybody wins: Those who can't wait to get their hands on new technology and those who are happy with the 645z!

Congrats. Lucky you. My budget was much lower so opted for the K1. I really wanted the Z. I even have three lenses for it already. I am now going to sell two of the three Z lenses.

[Sarnian]

Do you mean the discontinued 25mm? I don't have one, unfortunately. I will have a chance to borrow one from my friend for a trip to South America in November, so I will see how it works.

If you can, take a 645N/Nii as a second body. I have the 25mm DFA and on film it's equivalent to 15.5mm!

I'm going to hold on to it in case there's ever a full-frame 645Zii.