MoreMamiya Macro 140mm Questions

[heller_harris]

HI -

There's a fair bit of info on correctly adjusting the floating lens element, but I'd like to know what happens if

you do

NOT focus the floating element. Is the whole image slightly out of focus? Is it uniform, or do the edges go

softer than they might otherwise? Anyone have any images that were intentionally de-focused this way?

thanks,

Heller

[jim_momary]

Well, I use the 50 with the floating element. It's obviously not a macro, but I've only ever noticed an improvement in

edge sharpness with the floating element when at its closest focusing distance. What I saw, I think and it is

SUBTLE, is an increase in edge blur ... not an overall focus issue. At any focus point > 10 feet I suspect the DOF

goes out to infinity. The floater (in Nikon terms = CRC) is there to correct for edge softness due to speherical

abberations at real close distances. That's about the limit of my IQ on this subject. There's a booklet called 'Lenses

for Mamiya RB' (doesn't include the 140, sigh) that may be found on the web with more intell. Hope I'm being

accurate here. Jim M.

[randall ellis]

I have one of these, and I've never been able to tell the frames when I forgot to adjust it from those where I did adjust it properly (it happens from time to time <shrug>). I'm sure that there is some reason for the ability to make the adjustments, but I've not got the eyes to see it, either in the negatives or the prints. I don't think that you could use it as a soft focus effect though, if you want that, get the 150 with the disks.

 

- Randy

[spanky]

Here's a shot I took with the 50mm ULD. I cannot recall the exact f-stop but it was probably around f8. Film was

Delta 3200. Notice how the bottom of the image is out of focus and tends to curve up? It's this way on the neg to so

that rules out a possible out of alignment enlarger. The only other thing I can think of is I failed to reset the floating

element to the correct distance. I'd be interested in hearing other ideas but for now this seems to me the most likely

cause.<div></div>

[dean_waters]

I've run some tests on the floating element on a 65mm Sekor C and must say that I can't see much if any difference in edge sharpness when using it. The tests were based on shooting fine print at 1 m by flash with the cemera on a big tripod with mirror lock-up using the floating element ring set to 'inf' then '1m' It's supposed to just affect edge sharpness, not overall sharpness. I would expect more of a difference with the macro since shottign distances can be quite closeif you use both tubes, but I haven't run any tests. I would imagine you'd hardly ever notice it. I hardly ever remeber to set it anyway, and my images look shrap!

[heller_harris]

Thanks, everyone. <p>

Heller

[philfx]

I often have both tubes plus the TS adapter with the 140. anyone know if placing the TS on the body or between the lens makes a difference? I thinking of place the short ext tube on the body, then the TS (this allows my DB cable to fit without the adapter hitting the wire), then the long ext tube, then nthe 140. Also, someone was saying that some 140's dont have a floating element...how can you tell? some of the newer lens' have the green print on it with some calcs, but mine doesn't. How much better is the newer lens over the old(if there is this difference). On that note, as there are true macro folks on this thread...perhaps someone can shed some light on why the RZ system doesnt have a true proper TS bellows setup? I have invested everything towards the RZ setup with DB, and now that I am getting into my groove with it, it is lacking in the DOF that I want to get with my macro work. I couldnt find Novoflex or anyone making such a device...WHY?

Such a popular system, I am kinda lost why? I guess with wide angle or landscape the image circle ? But for macro...being a main use?