[rfkiii]

Thanks Jim.


Jim, here's the link to Part 1 I think. Thanks for the starting clue.


https://www.pentaxforums.com/forums/48-pentax-645d-medium-format/145963-penta...a-adapter.html


I'll study both posts and may be back to ask some more questions.

[RonHendriks1966]

I used the 645D for a few times.

A report on it from the 2012 trip with the set:
http://www.pentaxian.nl/index.php/topic,24313.0.html
It's in Dutch, but the 85 images do have their own message.

I think that with 55mm, 150mm and 300mm you can do a lot, but I'm no landscaper, so I never need wider lenses.

[rfkiii]

I used the 645D for a few times.

A report on it from the 2012 trip with the set:
http://www.pentaxian.nl/index.php/topic,24313.0.html
It's in Dutch, but the 85 images do have their own message.

I think that with 55mm, 150mm and 300mm you can do a lot, but I'm no landscaper, so I never need wider lenses.

Wonderful images. To pursue the type of landscape style I have settled into, yes, wider angle lenses would be necessary. The 55mm would be closer to normal than wide in terms of a 35mm equivalent but I'd probably acquire the lens anyway since it is one of the least expensive lenses in the Pentax 645 line-up and eventually all of them. The 25 & 90 will be the toughest nuts to crack in terms of my finances.

[rfkiii]

Why not the Pentax 645 lenses? With those you can control the aperture from the body, you are not limited to center weighted metering, and AWB is better. And with FA and DFA lenses, you have lens profiles. I have adapter a Pentax 67 lens to the 645D, but found the 645 lenses just as good if not better so why give up the benefits of 645 lenses?

I received a notice via email that this message had been posted to the thread, but I can't actually see the message here. Strange.


Nonetheless, my answers to the questions: I am researching all lenses available for use on the 645Z. Should I adopt the 645Z for my landscape pursuits, I will most likely own multiple Pentax lenses most of which do seem reasonably priced. I am thinking of alternatives for the 25mm which doesn't seem proportionately priced.

[Uluru]

I received a notice via email that this message had been posted to the thread, but I can't actually see the message here. Strange.


Nonetheless, my answers to the questions: I am researching all lenses available for use on the 645Z. Should I adopt the 645Z for my landscape pursuits, I will most likely own multiple Pentax lenses most of which do seem reasonably priced. I am thinking of alternatives for the 25mm which doesn't seem proportionately priced.

For a similar lens in 135 format, and in similar terms of quality, look at the prices of (utra) wide lenses like Leica Summilux 1.4/21,or Zeiss 2.8/15 Distagon. One is $7500 and the other $4600. Pentax 25mm for 645 is not any worse. Leica's own MF wide angle lens for its S system (3.5/24 Super-Elmar-S ASPH) costs $8995.

The price is high as it is an (ultra)wide angle lens for medium format.
Compared to all, Pentax 4/25mm is very competitive. And it has WR as a bonus.

---------- Post added 04-28-2014 at 11:54 PM ----------

On the other hand, digital photography provides one convenience: wide-angle panorama shooting. Using the K-mount system, I often substitute shooting ultra wide-angle lenses with several images taken with DA40 in manual mode. After the stitching, which is done by a computer, the results are phenomenal. I believe same can be done with 645Z files, at least in the beginning, using some less expensive lens. 4/25 is expensive, but I don't think it is really necessary to start with. (if you shoot weddings, then the stitching is damn difficult It only works for landscapes )
The results of the macro lens, on the other hand, is more difficult to emulate.

[desertscape]

(modern coatings used on Ver 2 releases of various Canon L lenses have made a great difference - coatings are nothing to dismiss lightl)y.

The Pentax film lenses for the 645 and 6x7 were all SMC (with a few exceptions on the Super-Takumars). This Super Multi Coat was a 7 layer anti reflection application to lens surfaces that is still outstanding in its results today.

[johnha]

It's worth pointing out that using lenses designed for the 645 film format will not be using the edges/corners of the image circle on a 645D/Z, so you're using the best parts of the glass and losing any aberrations towards those edges/corners. All Pentax medium format lenses were 'pro' grade lenses, there were no 'consumer' grade options.

[rfkiii]

For a similar lens in 135 format, and in similar terms of quality, look at the prices of (utra) wide lenses like Leica Summilux 1.4/21,or Zeiss 2.8/15 Distagon. One is $7500 and the other $4600. Pentax 25mm for 645 is not any worse. Leica's own MF wide angle lens for its S system (3.5/24 Super-Elmar-S ASPH) costs $8995.

The price is high as it is an (ultra)wide angle lens for medium format.
Compared to all, Pentax 4/25mm is very competitive. And it has WR as a bonus..

I probably wouldn't consider Leica at all. If the IQ of the Zeiss 15mm is equal to the Pentax 25mm, the Pentax would be a no-brainer. AF, native mount (no adapter), WR (I suppose WR means weather resistant).. Thanks for the thoughts on the topic.

---------- Post added 04-28-14 at 08:31 PM ----------

The Pentax film lenses for the 645 and 6x7 were all SMC (with a few exceptions on the Super-Takumars). This Super Multi Coat was a 7 layer anti reflection application to lens surfaces that is still outstanding in its results today.

I knew this from when I was researching Pentax 35mm lenses to adapt to my Canon but forgot it. Have there been variants of SMC over the years?

---------- Post added 04-28-14 at 08:36 PM ----------

It's worth pointing out that using lenses designed for the 645 film format will not be using the edges/corners of the image circle on a 645D/Z, so you're using the best parts of the glass and losing any aberrations towards those edges/corners. All Pentax medium format lenses were 'pro' grade lenses, there were no 'consumer' grade options.

Thanks. Much like FF lenses on an APS-C camera. Well...you know what I mean.

[gofour3]

Have there been variantsof SMC over the years?

I’m not sure about the Pentax 645 & 6x7 lenses, but the 35mm format SMC Takumars only had the SMC coatings on some lens surfaces, single coatings on some and no coatings on glass surfaces cemented together.

When the Pentax bayonet mount K Series was introduced in June 1975, SMC was applied to most glass surface in the lens that were previously single or non-coated.

The SMC 7-layer coating itself did not change.

Phil.

[funkysmurf]

I'd like to thank you all for your input. I'm still doing research on some of the Pentax lenses and I'm about to look into the flash system. I've made my own list of pros and cons about the possible switch from a Nikon 35mm system to a Pentax MFD one. So far, the pros are with the 35mm side by a relatively big margin. Regardless, I'm still excited about the 645Z and haven't made up my mind yet.

I have been unsuccessful in my efforts to get my hands on a 645D with any lens combination. None of the stores I rang in Sydney have a demo unit. With that in mind, I was wondering if any one would be generous enough to offer a raw file or two I could play around with that was captured by the 645D? I wanted to download a couple of raw files posted by an American dealer and taken by the IQ250 back, but it seems they've been taken down as they're transitioning from Dropbox to Google Drive.

From what I've seen so far, I think I would go with the 55mm, 150mm and 300mm lenses. This way I would not need to spend much to make the switch.
Please let me know if the raw file request is inappropriate and I'll remove it. Thanks.

[y0chang]

Before buying a 20k camera system i would rent a 645d and see if you like it. MF as mentioned by the previous posts has its own strengths and weaknesses. If you can find a rental you can find out if you like the MF experience, and sample the lenses that you would like to use.

Here is a good article about someone using a rented 645d.
Shooting Landscape Photography with the Pentax 645D | Photofocus

[bull drinkwater]

Funkysmurf- I recently bought a second hand 645D for portraits and weddings. Haven't had any in the three weeks or so since getting it, but am very enamoured with it. I also bought the only lens, a 75 FA. Strangely I haven't felt the urgency to buy another lens yet. I mean I know I will need more for weddings and other uses, but am just waiting until I find a great deal. The 75 is just a wonderful all around lens. I use it for close-ups and groups, even of covered bridges and candids. And Adam, I hand hold mine quite a bit. I find it very sharp this way, my wife not so much...I do bring along the tripod more often though. If I had to get just two more lenses, it would have to be the FA 33-55 and the FA 150 2.8. The zoom would be very useful in the pre ceremony and reception times, as well as a good wide angle for groups, and the 150 should give me the wonderful shallow DOF on full length brides that the 75 gives me on close ups. Of course there are others like the 120 macro because I find macro shots interesting, but not essential to business. Remember, with 40 or 50 mp you can shoot wide and crop in on events like weddings and still have plenty of detail. you don't have to have every single focal length in your case.

I was in the same boat, buy film or go digital. I chose the 645D. they say that normal for the 645d is 55mm, however since the 645d sensor is smaller than the 645 ,the 45mm would be normal for the 645d. I am one of the older guys with bad hands and shoulders., but I find it easy to shoot hand held with lenses from 45-200mm. however you choose to go, good luck.

[maxfield_photo]

55mm really is the normal focal length on the 645D (and soon to be 645Z). The sensor measures 44mm by 33mm, so by breaking out the old Pythagorean Theorem we can calculate that the diagonal is 55mm. It is the diagonal of the frame that determines the normal focal length of a particular format.

It's important to understand that this is the true normal FL, the equivalent of a 43mm lens on 35mm film or 75mm lens on a full frame 645. People tend to call 50mm "normal" on 135 format, and it's close enough, but I think it creates some confusion as to what "normal" really means. Technically speaking there is some perspective compression that occurs. So the equivalent of a 135 format "nifty fifty" on a full frame 645 camera would be 87mm lens, or 64mm lens on a "cropped sensor" MF camera like the 645D.

[Digitalis]

if manufacturers were to construct, say, an f/1.4 for a 4x5 camera, the depth of field would be so shallow when shot wide open as to make just about any image unusable.

Not to mention the fact that such a lens would weigh several kilograms, and it would be the size of a friggin watermelon.

[funkysmurf]

Not to mention the fact that such a lens would weigh several kilograms, and it would be the size of a friggin watermelon.

I like watermelons. The weight and size are a non-issue for me. I routinely use the D4 with the 200mm lens for hours at a time. Together they weigh 4.24kg.
This is me on the weekend on a Harley Davidson shoot - didn't have a ladder so the riders helped:


I've been trying to find a store with a demo 645D but no one seems to have one. I called three fairly large rental places in Sydney, and while they have the usual 35mm and Phase One systems, the Pentax is not on their list. I'm not really interested in trying out a film camera. In fact, I think that any modern higher end camera is generally good enough. It's more the lenses I'm concerned about as I think that they're a bigger factor in the final result than camera bodies.

In the coming weeks I'll be trying to find a place where I can try out the 645D with the lenses I had in mind, but with Pentax it's a little bit like trying to move from Windows to Linux.