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05-13-2015, 04:44 PM - 2 Likes   #1
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Evaluating Used Lens for 645Z

I've conducted a series of test shots to determine which lens to take on my upcoming vacation to Hawaii, we leave this Saturday. In the last few days I've purchased the 645 45-85 FA zoom, the 645 35 A, the 645 120 A macro and the 645 150 A. All of these were purchased on Ebay from US sources except the 35 wide angle was from KEH. The test shots were made from my front porch using a tripod and the 2 second shutter time delay to minimize vibration. From what I've learned from this forum the quality of these older lens varies from copy to copy. I was concerned since I recieved the 645Z less than 2 weeks before we depart for vacation and want to use the best lens from the bunch purchased having only limited time to put together a kit. The timing was the reason all lens were bought from US sources. I made test prints using an Epson 3880 printer at 8.5 x 11 size cropped significantly, using approx a third of the full frame size for the 55 mm lens. I used the D 55m lens print as the basis of comparison. The wide angle up to the 55 mm lens shots were cropped to the equivalent view size, not the equivalent magnification.

Here's a summary of what I've found so far.

645 35mm A. This was rated as a "bargain" quality lens from KEH - the best they had to offer at the time. The lens has cosmetic wear, but doesn't have fungus or element surface blemishes and the focus is smooth and secure. The test shot crop for this lens was quite severe to "blow it up" to match the 55mm lens crop. This copy proved to be quite sharp. It was able to resolve the power wires and detail quite well, however could not match the level of detail of the 55, as was expected. The lens does exhibit some distortion at the edges. I believe I've received a good copy of this lens.

645 45-85 FA zoom. At 45mm this lens, although cropped more than for the 55mm lens, produced a print that compares favorably to the D 55, producing nearly equivalent detail and contrast. The zoom's quality at 55mm is essentially equivalent to what it was at 45mm even though not cropped as much as at the 45mm setting. Again the D 55mm produced better results. By 85mm the quality falls off significantly. I'm debating on whether it is worth the weight to bring this lens on vacation, although the versatility of the zoom would be nice to have.

645 120mm A. Since this goes into the telephoto range, my interest was to compare it to the 150mm A. From what I've read on this forum, this macro isn't as good as the 150 when focused to infinity. To the contrary, this copy produces better contrast and detail than the 150. For this comparison I cropped the 150 field of view down to about one fourth frame size, a rather significant crop. I then matched the field of view for the 120mm macro. As indicated, the macro produced much better contrast and finer detail than the 150mm even though having been cropped more. I think I'm going to like this lens - and I only paid $170 with free shipping for it!! Is the FA 120mm lens version better?

645 150mm A. This lens does a decent job, however doesn't exhibit the level of contrast I'm seeing with the other lens. I'm going to sell this one. Would the FA version of this lens be better?

In case you're interested, my go to camera for the last two years has been the Sigma dp2m. I tested this camera/lens combination against the 645z/55mm setup. The field of view of the two lens is essentially the same. The dp2m does remarkably well in the comparison, especially in consideration of its aps size sensor. When cropped to the same size as used for other 645 lens (35mm, 45-85 zoom and D55) it resolves detail just a little less than the 45-85 zoom, however is lacking in contrast and color.

So, why spend upwards of $9k, when a $600 camera will do nearly as well? Or, in my case, why not wait for the Canon 5dr at less than half the cost of the 645Z? For me, the results of these tests confirm my purchase. The resolution, contrast range, and vibrancy of the colors justify the expense, and double the enjoyment!

As stated, the basis of evaluation was prints from the Epson 3880. I'm very impressed with the quality of this printer. The prints are on Costco glossy. Given the significance of the crops that were employed, even the distant telephone wires are resolved by the printer!

A conclusion I draw from these "out of the front door" tests is that the 645z sensor excels even with these older film camera era lens. I'm quite pleased. At this point I'm not sure that the D 90mm macro is $5000 better than the 120mm A, however, I'm not sure what lens I'll end up with. Larger prints will have to be made in the future.

I thought several of you would be interested in my findings so far.

Phil

05-14-2015, 01:53 AM   #2
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QuoteOriginally posted by PhilRich Quote
645 120mm A. Since this goes into the telephoto range, my interest was to compare it to the 150mm A. From what I've read on this forum, this macro isn't as good as the 150 when focused to infinity. To the contrary, this copy produces better contrast and detail than the 150. For this comparison I cropped the 150 field of view down to about one fourth frame size, a rather significant crop. I then matched the field of view for the 120mm macro. As indicated, the macro produced much better contrast and finer detail than the 150mm even though having been cropped more. I think I'm going to like this lens - and I only paid $170 with free shipping for it!! Is the FA 120mm lens version better?

645 150mm A. This lens does a decent job, however doesn't exhibit the level of contrast I'm seeing with the other lens. I'm going to sell this one. Would the FA version of this lens be better?
Hello, I have the FA 120mm and FA 150mm, and it is I that said my 150 is better at infinity stopped down, which it is... It also has sharper corners, at least my copy does.

As a disclaimer, I have no experience with the A lenses, but I am aware the A 150 3.5 is a different optical design to the FA 150 2.8 and cannot be directly compared.

Also keep in mind that there may be sample variance and that I could have a bunk 120 and an amazing 150, but I doubt it. Maybe I'll post some 100% crops later today and someone can give me a reality check.
05-14-2015, 01:51 PM   #3
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I have the latest 150 and it is staggeringly good.
05-14-2015, 04:09 PM   #4
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QuoteOriginally posted by gavincato Quote
I have the latest 150 and it is staggeringly good.
As do I, and I'd second that opinion.

05-14-2015, 04:44 PM   #5
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i also have the FA150/2.8 and I find the A120 Macro still edges it out.
05-14-2015, 06:15 PM   #6
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I've had all of these 645 lenses (and still have the DP2M). The 150 FA is a different deisgn from the 645 A. It is not necessarily much sharper - my A version was extremely good - but it is faster, focuses closer, and is AF.
The 120mm in A and FA is the same design, no difference. But AF is slow, so the A may be more desirable. Only the hood may be expensive.
Much depends on use, all of these are really good lenses, so your personal demand is what should inform your choices, not marginal differences that are irrelevant to your shooting.
I decided in the end not to go digital (apart from the DP2M), but if I had, I would have kept the 35 A (which is very, very good), and the 120 or 150mm (for film I kept the FA 150mm, but for digital I would probably have kept the 120mm together with a 55 and 75mm).
I also had the 67 55mm with adapter, which is extremely good, heavy, much better than the A 55mm, and allegedly better than the FDA 55mm (don't know, did not have it).
Apart from the occasional use of the Sigmas, I'm an analogue user, preferring the square format.
05-14-2015, 06:21 PM   #7
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I always go and look at this article by Michael Reichmann from 2009 - old, but still relevant. Here he compared a small Canon G-10 with the Hasselblad P45, a medium format camera. The results will surprise most people.

It is, IMHO not the small prints that will tell the difference but much larger sizes and I found that the prints from larger, higher resolution sensors are more 'immersive' and detailed. There is something about the fine detail in the distance that makes an image appear more '3D', at least that is how I feel.

My own evaluation of what I have (four of my six lenses were bought used) suggests that it is not easy to compare all the lenses at all apertures without having a standard target and being careful in taking the shots. A rough analysis suggests that the sharpest lens I own is the 55 DFA. The others are sharp enough in the 'backyard tests', wonder how they will do in the real world conditions on tours and travels.

Pradeep
05-15-2015, 08:29 AM   #8
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Phil

Great analysis and it is truly helpful.

Most of the article talks about real experiences while testing lenses you actually own. That is the way to go. However at the very end of the article you mention that the new 90 macro (which you don't own) might not be better than an old 120A (which you do own). You might be right, but I have found that the new 645 FA/DFA lenses are the sharpest I own (including the 90 which I got for 35% off for a new copy from Japan), even though I went the route of buying older lenses which fit into my FL needs and uses. For example my "new" A35/3.5 is wonderful such as yours is and I have used it for street use by zone focusing or letting the Z beep me when optimal focus is reached.

We all might have different experiences with the same lens I guess due to lens variation and so many other variables it would take forever to list. I just think we should be careful saying that this or that lens is good or bad for us when we have not had it in hand to know for sure.

05-15-2015, 11:36 AM   #9
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Original Poster
Thanks for the replies and interest in this thread.

Algrove - I appreciate your comments. I was musing concerning the D 90mm macro wondering if it was indeed $5000 better than the copy of the A 120mm that I have, i.e., worth the extra $$ to me. Apparently from your experience, at $5000 x .65 it is better and worth it!

At any rate, the 645Z will be an interesting journey.
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