What are the best lenses for Pentax 645D for a landscape photog?

[Codger]

After a dozen years using medium format (6x7) film, I'm accepting that I need to be positioning for a transition to digital this year.  I'd love to have an H4D-40 kit but the entry "fee" exceeds my means.  The reviews on the Pentax are sufficiently appealing I'm considering it, but the dearth of lenses concerns me.  I do 80% of my work with (35mm equiv) four lenses that range between 28mm and 90mm.  Suggestions?

[theguywitha645d]

I am using the manual focus A 35mm (28mm equiv.), AF DFA 55mm (43mm equiv.), and the manual focus A 120mm macro (~90mm equiv.). ("A" designates a manual lens and "FA" an autofocus one. Not all A and FA lenses have the same optics and sometimes the A is better than the FA.) I am very happy with all of them. I have done a number of landscapes with the marco and it is very sharp. The 120mm is universally praised both the manual and AF versions. I think the DFA 55mm is very underrated--I have always gotten good results from it. The 35mm is nice, but can flare when pointing into the sun, still it is sharp and I picked up a really nice copy for about $450, although they have a reputation of being better in the corners than the AF 35mm and can be list at nearly $1000 with the AF version being about $1600.

I have not found it difficult to find the lenses I have wanted. Pentax 645 accessories are plentiful as well. I also purchased a 90 degree angle finder--AKA Refconverter--which is very nice and useful.

I would also ask in the medium-format section of the Pentax forums for advice. There are a number of 645D owners and examples over there.

[ErikKaffehr]

Hi,

My experience is that 24 MP full frame digital essentially matches and surpasses the image quality of my Pentax 67 film camera with the technique I use. So I'd suggest that any full format system would be a good replacement for a Pentax 67.

My test is here: http://echophoto.dnsalias.net/ekr/index.php/photoarticles/16-pentax67velvia-vs-sony-alpha-900

As a side note, I just repeated the test with negative film (Kodak Ektar 100) and the impression I have is that the outcome will be similar to the first test.

So, my first suggestion is that the full frame 20+ MP cameras on the market are good replacements for 67 analogue, and save you money.

The Pentax 645D is without doubt a good step up from full frame 135 digital, and it is not much more expensive than the best full frame DSLR (the Nikon D3X).

Regarding the lenses, Lloyd Chambers has tested many of them. He has a large amount of information here: http://www.diglloyd.com/prem/prot/DAP/index.html#Pentax645D, acessing the site costs a couple dollars, but may be wort if you are planning to shell out like 20k$

Best regards
Erik

After a dozen years using medium format (6x7) film, I'm accepting that I need to be positioning for a transition to digital this year.  I'd love to have an H4D-40 kit but the entry "fee" exceeds my means.  The reviews on the Pentax are sufficiently appealing I'm considering it, but the dearth of lenses concerns me.  I do 80% of my work with (35mm equiv) four lenses that range between 28mm and 90mm.  Suggestions?

[theguywitha645d]

Just to let you know, not every 645D user actually arrived at the same conclusion as Mr. Chambers. It is a good source of information, but it is not definitive. And regardless of those results, you are not going to find 35mm sensors really competing with the 645D.

You will find the DoF characteristic really changing from the 6x7 format you were shooting. That is simply the difference in format size. The images from my 645D are different from the medium-format film I shoot. It is not about simply about resolving power, but the DoF and the difference i the film/digital rendering. I amreally happy with my 645D, but it is not giving the same results as my film.

[tsjanik]

Codger:

Given the 28-90mm range, I would suggest: 35mm A or FA (there are reports that the A version is better on the 645D, which is surprising considering the reputation of the FA).  In any event, my A copy is excellent.  75mm A or FA, both excellent, although the AF is nice to have.  120mm macro A or FA, although if you plan to use the lens for macro shots the A version is much better for manual focus.
My 55mm A is good in the center, weaker at the edges, but fine for many landscapes.  I have no experience with DFA version.  The 67 55mm (latest version) is superb, but you need the 67/645 adapter.  You might also consider the 45-85mm zoom, which is excellent especially at the wide end.  It is heavy and makes the camera less portable however.
I was a Pentax 67/645N user until December when I got the 645D.   I ordered the camera largely on faith in October; for me it was a logical gamble as I already had many Pentax 67/645 lenses.  I have not been disappointed in any way by the camera (although I think the 645N is a much more attractive camera).  Lloyd Chambers does a very thorough test and he found some lenses to be excellent  and some less so, but keep in mind he was testing one copy of a used lens in most cases (I supplied two of the lenses he tested).  The only lens that is universally regarded by users of the camera as sub-par is the 45mm.   If you plan on using any of the manual focus lenses wide-open, the Pentax 2x magnifier (or equivalent) is really helpful.  Aside from finding the 2x essential for some applications, I have not had any focus issues with the camera or lenses. 

Tom

[Codger]

Some good info emerging here, thanks to the Forum's collective insights.  Am I hearing that DOF is going to be LESS on the 645D compared with my 6x7 film system?  I've had a feeling the smooth color transitions of twilight skies might look different through digital capture, but that wouldn't necessarily be a negative -- just different.

[tsjanik]

My one unpleasant surprise in the switch to digital is how sensors handle the sun.  Film’s non-linear response gracefully transitions to complete saturation, not so with digital.  If you want the sun in the picture, it changes how you calculate your exposure.  Here’s a sample I posted:
http://www.luminous-landscape.com/forum/index.php?topic=53180.msg435728

[Cineski]

Resolution isn't the only comparison that should be made.  Take a wide shot with a 24mm on full frame and then take the same shot with a 55mm on 6x7.

[ErikKaffehr]

Hi,

Sensor is smaller so DOF will actually be more. On the other hand, we tend to pixel peep digital images another way than with film. So definition of acceptable sharpness may be different.

This article discusses DoF in digital pictures: http://echophoto.dnsalias.net/ekr/index.php/photoarticles/49-dof-in-digital-pictures?start=1 the top rightmost picture is about what DoF scales are based on.

The article was written because one Pentax 645D user found that background was out of focus when he focused his 150 mm lens at f/8 on an object 200 m away.

Why do we pixel peep? Because it is easy. Looking at an image at "actual pixels" is like looking at film with a decent microscope!

Best reagrds
Erik

Some good info emerging here, thanks to the Forum's collective insights.  Am I hearing that DOF is going to be LESS on the 645D compared with my 6x7 film system?  I've had a feeling the smooth color transitions of twilight skies might look different through digital capture, but that wouldn't necessarily be a negative -- just different.

[ErikKaffehr]

This is absolutely correct. Check the enclosed image. Negative film rolls of softly (ektar on the left) digital is essentially linear. Illumination on wedge is probably not even, but it was the same between the two exposures.

Best regards
Erik

My one unpleasant surprise in the switch to digital is how sensors handle the sun.  Film’s non-linear response gracefully transitions to complete saturation, not so with digital.  If you want the sun in the picture, it changes how you calculate your exposure.  Here’s a sample I posted:
http://www.luminous-landscape.com/forum/index.php?topic=53180.msg435728

[Cineski]

Correct, which can be a benefit or hinderance depending on what you want to do, but a 24mm on a 35mm camera will have much different diminishing background compared to a 55mm on 6x7.

Hi,

Sensor is smaller so DOF will actually be more. On the other hand, we tend to pixel peep digital images another way than with film. So definition of acceptable sharpness may be different.

This article discusses DoF in digital pictures: http://echophoto.dnsalias.net/ekr/index.php/photoarticles/49-dof-in-digital-pictures?start=1 the top rightmost picture is about what DoF scales are based on.

The article was written because one Pentax 645D user found that background was out of focus when he focused his 150 mm lens at f/8 on an object 200 m away.

Why do we pixel peep? Because it is easy. Looking at an image at "actual pixels" is like looking at film with a decent microscope!

Best reagrds
Erik

[ErikKaffehr]

Hi!

The question by the original poster was weather P645D would have less DoF than 67 film. So please don't mix in 24 mm on 35 mm camera. It's just causing confusion.

Best regards
Erik

Correct, which can be a benefit or hinderance depending on what you want to do, but a 24mm on a 35mm camera will have much different diminishing background compared to a 55mm on 6x7.

[Cineski]

Actually I can't see that he did in his original question.  Someone else brought depth of field up and it spawned some new questions for the OP.  I don't see what's wrong with discussing things in an open question like this:

Original Post:  After a dozen years using medium format (6x7) film, I'm accepting that I need to be positioning for a transition to digital this year.  I'd love to have an H4D-40 kit but the entry "fee" exceeds my means.  The reviews on the Pentax are sufficiently appealing I'm considering it, but the dearth of lenses concerns me.  I do 80% of my work with (35mm equiv) four lenses that range between 28mm and 90mm.  Suggestions?

Narrow minding discussion doesn't bring up things the OP may not have thought of....like depth of field.

Hi!

The question by the original poster was weather P645D would have less DoF than 67 film. So please don't mix in 24 mm on 35 mm camera. It's just causing confusion.

Best regards
Erik

[theguywitha645d]

DoF will be greater with the 645D. As stated above, simply because of sensor size. MFD does not change DoF characteristics. Unfortunately lots of folks are pixel peepers and so at 100% DoF is not correctly rendered. Pixel peeping is in no way a real world viewing condition.

[ErikKaffehr]

Hi,

Reply #5 by Codger brought DoF into discussion. Codger is original poster. Replay 5 is not original posting but original poster, sorry for being rude.

Best regards
Erik

Actually I can't see that he did in his original question.  Someone else brought depth of field up and it spawned some new questions for the OP.  I don't see what's wrong with discussing things in an open question like this:

Original Post:  After a dozen years using medium format (6x7) film, I'm accepting that I need to be positioning for a transition to digital this year.  I'd love to have an H4D-40 kit but the entry "fee" exceeds my means.  The reviews on the Pentax are sufficiently appealing I'm considering it, but the dearth of lenses concerns me.  I do 80% of my work with (35mm equiv) four lenses that range between 28mm and 90mm.  Suggestions?

Narrow minding discussion doesn't bring up things the OP may not have thought of....like depth of field.

[ErikKaffehr]

Well, yes and now, IMHO.

I have 70x100 cm print made from APS-C at 10 MP on my wall. It's lacking in sharpness from close, but seen from a meter or so it doesn't matter. You don't see the fine detail and sharpening takes care of the rest. I also have an A2 print on my wall, taken with a 6MP camera. It's a really good picture, but it is lacking detail. No one complains, tough.

On the other hand I'd suppose that the main reason to invest in MF digital is that the purchaser strives for optimal quality, and that quality won't be there at f/32.

Many authors claim that about 12 MPixels are all that are needed, there is some truth to that. But if you don't print large and view close there is little reason to invest 20000 kUSD in an MF equipment.

Best regards
Erik

Pixel peeping is in no way a real world viewing condition.

[theguywitha645d]

Erik, I just hung a 12' pano. I am sure the concepts of viewing conditions apply today just as well as they have in the past--we don't have different eyes. That is not to say you cannot see the difference in different formats, but to judge sharpness and DoF, 100% monitor views are not real world and the more pixels, the more other-worldly the view is. And I often shoot MFD at f/16 and f/22--f/32 is too small for the format. Diffraction is not really a problem--unless you pixel peep and compare. Detail is a different topic entirely.

The more things change, the more they remain the same...

Don't sweat the small stuff. (The abbreviation for Medium-format Digital is not OCD.)

Well, yes and now, IMHO.

I have 70x100 cm print made from APS-C at 10 MP on my wall. It's lacking in sharpness from close, but seen from a meter or so it doesn't matter. You don't see the fine detail and sharpening takes care of the rest. I also have an A2 print on my wall, taken with a 6MP camera. It's a really good picture, but it is lacking detail. No one complains, tough.

On the other hand I'd suppose that the main reason to invest in MF digital is that the purchaser strives for optimal quality, and that quality won't be there at f/32.

Many authors claim that about 12 MPixels are all that are needed, there is some truth to that. But if you don't print large and view close there is little reason to invest 20000 kUSD in an MF equipment.

Best regards
Erik

[JDOAK]

I've tested and used 3 Pentax 645 lenses on the 645D: the Pentax 645 FA 35mm f/3.5, the Pentax 645 FA 45-85mm f/4.5, and the Pentax 645 FA 80-160mm f4.5.   All tested very sharp which has been confirmed by actual photos.  My copy of the 35mm f3/5 is very sharp at f8 and smaller apertures; at f6.7 and wider it is somewhat soft in the upper right quadrant.  The 80-160mm f4.5 is soft above 150mm, so it is practically useful from 80-150mm.  Other than that, all 3 lenses are superb.  I have found it necessary to do focus stacking to get the most out of the lenses, as each of them has some field curvature. 

I posted the quantitative test results on my website at http://www.sublimelightlp.com/blog.  They can be downloaded as a pdf file.  Hope this helps. 

J Dupuie

www.sublimelightlp.com

[Royce Howland]

My 645D and lenses accumulated during the past year are not leaving me wanting for much. This is what I usually have close by, for landscapes:

• A (manual) or FA (autofocus) 35mm. I have both. The A was quite a bit cheaper, the FA was purchased as new-old-stock long before I even ordered the body. My FA has an odd issue that I've described on PentaxForums.com, a strange form of mustache distortion (or perhaps it's a circular band of extreme loss of MTF as suggested to me by someone), when manually focusing the center of frame on a subject at infinity. The A does not exhibit this characteristic, and is marginally sharper in the corners but slightly less sharp center of frame. If I autofocus the FA lens on the infinity subject at the same aperture, the distortion effect doesn't show up, so it seems there's a region of focus where the optics fall apart in a particular band.
• FA 45-85mm zoom. A fine lens, and usually what I have mounted by default for wide-ish to normal-ish angles.
• FA 80-160mm zoom. Also a fine lens, used when I want to extract some tighter landscape features.
• FA 200mm. A nice, light, sharp tele prime for extracting tighter details.
• A 120mm macro. An excellent lens for closeups and other mid-range tele uses.

Aside from the oddness with my FA 35mm, which I have yet to fully break down and understand, I don't hesitate to reach for any of these lenses. I've spent little time "testing" lenses; despite my good intentions to shoot tests, the camera system is so satisfying to use for actual shooting that I spend all my time doing that.

I also have a bunch of other lenses picked up during the same time. These include the FA* 300mm (used mostly for wildlife), and a collection of Pentax 67 lenses that I was interested in trying out. Of the latter, I enjoy the 105mm f/2.4, trying my hand at portraiture with it.

The only lens I actually bought that I considered a true dud, was the new DFA 55mm. I didn't like mine and returned it. I read numerous reports that the various 45mm lenses were not acceptable either, and never tried one; every new report from somebody who tries one seems to continue to demonstrate that they're not a good fit for the 645D.

So I wouldn't say there's a "dearth" of lenses for the 645D. I've found some as new-old-stock, quite a few used at KEH, and a few from other sources. Total layout for lenses so far has been less than the body cost, by a fair amount. But if I try the new DFA 25mm and like it enough to keep it, that will change.

[smhoer]

Royce,
First a thanks on your HDR technique from NatureScapes.  Been using it for a couple years now and has made a huge difference in how I shoot.

Regarding the 35mm.  Do you find yourself reaching for the A more than the FA?  Is the center sharpness difference that noticeable at f8-11?

I do agree with you on the 25mm.  I see an expensive purchase in my near term future.

Scott