645 or 35mm... scanning?

"keith taylor" wrote in message
...
i don't think dof is an issue, if i remember correctly the 645 was taken
at f16. what concerns me more is that i'm not actually getting any more
data out of the 120 film than i am out of 35mm, for my purposes anyway.

currently i've only just dipped my toe into mf having bought a etrsi
with 75mm pe lens. if i were to continue i would want to buy an ae3
viewfinder, 40mm lens and possibly something round a 150mm. all this
will set me back quite a bit and for the perceived increase in quality i
don't think it's worth it.

If you aren't getting twice the detail from 645 than you are from 35mm, then
you are doing something seriously wrong at some point in the chain.
Inadequate tripod, focus problems, defective camera, or (most likely)
incompetent scanner operator.

A cheap 6x6 TLR should blow 35mm out of the water.

Whether getting everything right is worth the effort is another question.

perhaps in a few years time i may consider 6x7, but i don't see much
point continuing with 645.

You should be able to make far better 11x14s and 13x19s from 645 than 35mm.
But as Rafe hinted, scanning 645 is hard: you have to make a serious effort
at getting the film flat and the scanner focused at a point in the center of
the range of distances on the film. I doubt that any lab is at all as
careful as I am, or as is required for getting good scans from the Nikon
8000 or 9000.

What's worse, is that if you can't get more from 645 than you do from 35mm,
you probably won't get any more from 6x7. 6x7 is only 23% larger than 645,
which is small compared to the 55% larger that 645 is over 35mm (linear
dimension comparison).

David J. Littleboy
Tokyo, Japan

keith taylor wrote:
i don't think dof is an issue, if i remember correctly the 645 was
taken
at f16. what concerns me more is that i'm not actually getting any
more
data out of the 120 film than i am out of 35mm, for my purposes
anyway.

currently i've only just dipped my toe into mf having bought a etrsi
with 75mm pe lens. if i were to continue i would want to buy an ae3
viewfinder, 40mm lens and possibly something round a 150mm. all this
will set me back quite a bit and for the perceived increase in
quality i
don't think it's worth it.

perhaps in a few years time i may consider 6x7, but i don't see much
point continuing with 645.

Do a similar blowup of that rock in the middle of the stream that looks
to have leaves on it. I am guessing that will be more in focus and
hopefully the Bronica image will have more detail. Just picking on one
part of the image that might not be fully in focus is not a good
comparison and no sound basis for making a major decision.

i've posted another example. the rock with leaves on in the middle of
the river. both examples are unsharpened.

http://www.marona.co.uk/vuescan/medium.html

don't get me wrong i'm not criticising mf, i'm sure without a doubt that
there is far more information in the 645 trans, but my problem is
getting at that information. i don't have a mf scanner at my disposal,
whereas i do have a 35mm one. i don't doubt that if i could scan mf at
5400 dpi there would be no competition at all. but i'm merely looking at
the difference between 35mm at 5400dpi and mf at 4000dpi and i don't
think there is a huge amount in it.

keith


RolandRB wrote:
keith taylor wrote:

i don't think dof is an issue, if i remember correctly the 645 was

taken

at f16. what concerns me more is that i'm not actually getting any

more

data out of the 120 film than i am out of 35mm, for my purposes

anyway.

currently i've only just dipped my toe into mf having bought a etrsi
with 75mm pe lens. if i were to continue i would want to buy an ae3
viewfinder, 40mm lens and possibly something round a 150mm. all this
will set me back quite a bit and for the perceived increase in

quality i

don't think it's worth it.

perhaps in a few years time i may consider 6x7, but i don't see much
point continuing with 645.


Do a similar blowup of that rock in the middle of the stream that looks
to have leaves on it. I am guessing that will be more in focus and
hopefully the Bronica image will have more detail. Just picking on one
part of the image that might not be fully in focus is not a good
comparison and no sound basis for making a major decision.

keith taylor wrote:
i've posted another example. the rock with leaves on in the middle of

the river. both examples are unsharpened.

http://www.marona.co.uk/vuescan/medium.html

don't get me wrong i'm not criticising mf, i'm sure without a doubt
that
there is far more information in the 645 trans, but my problem is
getting at that information. i don't have a mf scanner at my
disposal,
whereas i do have a 35mm one. i don't doubt that if i could scan mf
at
5400 dpi there would be no competition at all. but i'm merely looking
at
the difference between 35mm at 5400dpi and mf at 4000dpi and i don't
think there is a huge amount in it.

keith

That's more like it. To me, at least, the 645 image of the rock in the
water is much sharper than that of the 35mm image.

35mm lenses are more highly corrected than medium format lenses.
Provided the film is sharp enough, you won't see much difference. The
main advantage of medium format is finer garin and better tonality, not
detail as such.

"keith taylor" wrote:

i've posted another example. the rock with leaves on in the middle of
the river. both examples are unsharpened.

http://www.marona.co.uk/vuescan/medium.html

don't get me wrong i'm not criticising mf, i'm sure without a doubt that
there is far more information in the 645 trans, but my problem is
getting at that information.

Yep. It's a problem.

i don't have a mf scanner at my disposal,
whereas i do have a 35mm one. i don't doubt that if i could scan mf at
5400 dpi there would be no competition at all. but i'm merely looking at
the difference between 35mm at 5400dpi and mf at 4000dpi and i don't
think there is a huge amount in it.

I still think you are looking at a good 5400 dpi scan vs. a bad 4000 dpi
scan. I don't see any significant detail in my MF negs and slides with a 60x
microscope that's not captured by my Nikon 8000 scanner, and a scan from a
sharp slide or neg is 6000 x 8800 pixels that look very good printed at 450
dpi. That's a 13x19, and 35mm at that size is a 14x enlargement, which is
going to be soft however you scan or print.

Again, after 3 years with the Nikon 8000, I just don't see how a lab could
get good scans with one. The DOF is just too narrow, making focus accuracy
really painful. Being off by 20 focus units will lose enough sharpness that
the MF advantage is gone, and the time required to hold focus within +/- 10
units across the frame is simply more than you can afford to pay for. Since
they can't charge you for their time, they don't spend the time. (Drum
scanners and Imacon scanners don't have that problem.)

(There is, of course, a small chance you messed up the MF shot, but I doubt
it.)

David J. Littleboy
Tokyo, Japan

"keith taylor" wrote:

i've posted another example. the rock with leaves on in the middle of
the river. both examples are unsharpened.

http://www.marona.co.uk/vuescan/medium.html

don't get me wrong i'm not criticising mf, i'm sure without a doubt that
there is far more information in the 645 trans, but my problem is
getting at that information.

Yep. It's a problem.

i don't have a mf scanner at my disposal,
whereas i do have a 35mm one. i don't doubt that if i could scan mf at
5400 dpi there would be no competition at all. but i'm merely looking at
the difference between 35mm at 5400dpi and mf at 4000dpi and i don't
think there is a huge amount in it.

I still think you are looking at a good 5400 dpi scan vs. a bad 4000 dpi
scan. I don't see any significant detail in my MF negs and slides with a 60x
microscope that's not captured by my Nikon 8000 scanner, and a scan from a
sharp slide or neg is 6000 x 8800 pixels that look very good printed at 450
dpi. That's a 13x19, and 35mm at that size is a 14x enlargement, which is
going to be soft however you scan or print.

Again, after 3 years with the Nikon 8000, I just don't see how a lab could
get good scans with one. The DOF is just too narrow, making focus accuracy
really painful. Being off by 20 focus units will lose enough sharpness that
the MF advantage is gone, and the time required to hold focus within +/- 10
units across the frame is simply more than you can afford to pay for. Since
they can't charge you for their time, they don't spend the time. (Drum
scanners and Imacon scanners don't have that problem.)

(There is, of course, a small chance you messed up the MF shot, but I doubt
it.)

David J. Littleboy
Tokyo, Japan

yes it is a little sharper, but not much more detail, you can copy the
images and sharpen them yourself, then there isn't much in it.


RolandRB wrote:
keith taylor wrote:

i've posted another example. the rock with leaves on in the middle of


the river. both examples are unsharpened.

http://www.marona.co.uk/vuescan/medium.html

don't get me wrong i'm not criticising mf, i'm sure without a doubt

that

there is far more information in the 645 trans, but my problem is
getting at that information. i don't have a mf scanner at my

disposal,

whereas i do have a 35mm one. i don't doubt that if i could scan mf

at

5400 dpi there would be no competition at all. but i'm merely looking

at

the difference between 35mm at 5400dpi and mf at 4000dpi and i don't
think there is a huge amount in it.

keith


That's more like it. To me, at least, the 645 image of the rock in the
water is much sharper than that of the 35mm image.

yes it is a little sharper, but not much more detail, you can copy the
images and sharpen them yourself, then there isn't much in it.


RolandRB wrote:
keith taylor wrote:

i've posted another example. the rock with leaves on in the middle of


the river. both examples are unsharpened.

http://www.marona.co.uk/vuescan/medium.html

don't get me wrong i'm not criticising mf, i'm sure without a doubt

that

there is far more information in the 645 trans, but my problem is
getting at that information. i don't have a mf scanner at my

disposal,

whereas i do have a 35mm one. i don't doubt that if i could scan mf

at

5400 dpi there would be no competition at all. but i'm merely looking

at

the difference between 35mm at 5400dpi and mf at 4000dpi and i don't
think there is a huge amount in it.

keith


That's more like it. To me, at least, the 645 image of the rock in the
water is much sharper than that of the 35mm image.

keith taylor wrote:
...
the difference between 35mm at 5400dpi and mf at 4000dpi and i don't
think there is a huge amount in it.

If the scans are as sharp as their nominal values, a 35mm frame at
5400dpi is the eqiuvalent of a 32x48mm at 400dpi. Not that far from the
42x56mm of a 645 frame.

-- Lassi