john_d._bridgman

For transparencies, you have three emulsions that age

at different rates. So I think that the effects of

aging will not affect the emulsions exactly the same

way.

What "aging" is is chemical reactions going on and on-

going as film sits unprocessed. The effect is not that

bad. That is I keep my film in the freezer. However I

often have film in my cameras for months before it is

developed. To me the results look ok.

If however someone was paying me $2000 a shot to meet

deatlines at a specific quality level, I would make sure

I was using emulsions of the same age and properly

stored, and used asap.

Depends on what you require for your work.

jdb

The 35mm focal length lens for the Mamiya 645 needs to be stopped

way down to be sharp corner to corner (f11, at least; f22 or f32 is

better). That is my experience from trying two specimens in 1996.

<p>

I recommend that you shot at least one roll of film and check

out this sharpness issue to make sure you know what you will

get. Have fun...

I do the same with my Mamiya 645 Pro as with my Nikon lenses:

always have a skylight filter on. I like the bit of extra

warmth. But mainly I like the extra protection in case I drop

the lens on the front (so far that has never happened).

<p>

No, I've never compared images with the filter on versus

off.

I used one quit awhile ago when I could not afford a 1 degree

spot meter. Worked fine. There is not much I can say. It was

better than 30 degrees and 1/7 as good as 1 degree (when you

needed to meter that small spot). The added sensitivity of the

LunaPro, over other meters of the time, meant that the reduced

sensitivity due to the smaller spot was not a big problem.

<p>

As to comparing it to your Canon, I have no idea other than

comparing the coverages and sensitivity.

If most of your prints (or presentation media) will be square,

I would go with the Hassy. You are familiar with this and there

is lots of used equipment out there.

<p>

However if you present results in rectangles, I would suggest

a 67 (or the largest format that fits within your weight limits).

I have handled the Mamiya RZII, and the view through the std view

finder is beautiful. And the image size of 67 is enough bigger than

6x6, that the decreased magnification for the same print size of

the larger image would more than compensate for any difference

in lens characteristics (that is, in my opinion, of course:).

<p>

jdb

I suggest you rent one and try the lenses you are interested

in. For example, if you use v.wide lenses, the 35mm focal

length lens needs to be closed down below f11 to get even

sharpness across the field (I was surprised when I tested

two copies of this lens and found it was unuseable for me

at f8 or f5.6).

<p>

I like the 120 Macro lens and the 50mm shift lens (though the

latter does require more concentration when using). The

300mm f5.6 lens also is ok (though I recently had a glitch

using this lens with the AE prism). The prices for their

500mm and 300mm APO teles are rediculous.

<p>

I repeat, rent and try.

I have the 50mm f4 shift lens for the Mamiya 645PRO. For me this lens is an

"emergency only" glass. I like to walk around and shoot, carrying all my

camera equipment. That means I have one system with me. Thus this lens

allows me to control converging lines, if I feel I have to. It works fairly well,

and unshifted, serves as a fine wide angle. However I did not get it to do

architectural work. It is way too limited.

<p>

If architecture is a principle focus of your efforts, you need to go to a view camera.

Or perhaps the Canon with its three swing/tilt lenses may work, if you can get

by with the 35mm format.

<p>

For the price of the RZ 75mm shift lens, you could get a used 4x5 camera,

older Super Angulon lens (75mm or 90mm), 4x5 film holders and film.

<p>

jdb

Thanks to Tony for the original message, and the additional comments. This issue has

confused me and this discussion clears up my confusion.

I would expect vignetting to affect exposure, not so much focus. I do have experience

with the Mamiya 35mm f3.5 lens. I photographed a rock wall at about 150 feet away

that was long enough to span the film diagonal. Until I had stopped down to f11 or

f16, only the center 1/2 of the image was sharp. I consider this horrible. I had heard

that the 45mm lens was better. But your experience does not seem to match that.

<p>

I would try exposures that test focus across the field, starting at wide open and then

closed 2 stops; then closed two more stops, etc. I would do this with the plain lens

(no filters or additions; and focus at or near infinity). Of course for completeness,

you may want to also test closer distances. It burns a roll of film, but well worthwhile,

I think.

<p>

jdb

You can go to the Schneider page (www.schneideroptics.com/large/large.htm.

For the 47mmf5.6 XL, it is 3 stops down

at the corners ofa 4x5 piece of film

(166mm diag). It is about 2 1/2 stops

down at a diag of 125 mm. For 5x7

(6x17), the 72 and 90 XL are similarly

dimmed at the far reaches of their image

circles (this is at f22, of course).

<p>

Don't know if Fugi has some magic for

its lenses or not.

<p>

jdb

Does anyone listening know the difference between the Horseman 985

and VHR (I think that is the designation) 6X9 press-view camera?

<p>

Thanks.

<p>

jdb