A question of comparison

[turgut_tarhan]

If I take the photographs of a scenery at infinity, using Velvia, one

with Minolta X-300 body & 50mm MD Rokkor f/1.7(the best lens I own),

closed to f/8, then another with Pentax 67 45mm or 55mm SMC Pentax

lens at f/8 or whatever their sharpest is, and cropping out a 24x36mm

frame from the center, both done with best efforts (eg. proper tripod

and MLU) to achieve the maximum; will the results be equivalent, or

to the favor of any? If equal, than can I can simply say, by applying

a good technique, the resolution at the horizontal will be doubled,

which will yield double-size prints? The reason of this question is

that I demand at least laterally 2x total resolution that will worth

the money, weight and other inconvenience issues, switching from 35mm

to MF.

[ian_maclennan]

Hi Turgut

 

I use 35mm, 645, and 6x7 kit and if I interpret your question correctly you are really asking if the quality of 6x7 is going to be moticeably better than 35mm. I regularly trek over the Scottish Highlands in all weathers with a heavy Pentax 67 system, and the only reason I suffer the pain of the weight and inconvenience is because 6x7 quality blows 35 mm away. This quality has nothing to do with the relative merit of 35mm vs 6x7 lenses - it arises simply because a 6x7 tranny is 4.5 times greater in area than a 35 mm tranny. Go borrow or hire a 6x7 camera and take comparison shots on Velvia with a 35mm camera. Make 16x20 prints from both systems and the difference in quality will be blindingly obvious. As to whether the pain of lugging the weight of the kit about is worthwhile - well that's very subjective! Hope this helps.

 

Ian MacLennan

[george_rhodes]

TEST

[george_rhodes]

For some reason, my first response would not post. I shoot scenics. I still shoot some 35mm, but now shoot almost exclusively with the pentax 6X7 system. There simply is no comparison between a 24" X 30" print made from a 6X7 negative/transparency, compared to one made from a 4.5 times smaller 35mm negative/transparency. With 6X7 you have 4.5 times less grain and many times the resolution. I'm not sure if the central portion of a 6X7 negative/transparency the same size as a 35mm frame has the same resolution as the 35mm frame or not, but it doesn't have to in order to produce a far superior image. It certainly has many times the resolution as the 35mm negative/transparency. I can tell you that my Pentax lenses, including my 90-180mm zoom, are darn sharp, producing razor sharp 30" prints with almost no grain. I recommend that you rent a 6X7 camera and shoot a roll of transpare4ncies. When you get back your first roll of film, you'll be a convert. You won't even need a loop to proof your transparencies. 6X7 equipment is much heavier, bulkier and slower to work with than 35mm, but for scenics, especially if you plan to make large prints, there simply is no comparison.

[steve_rasmussen]

Generally MF SLR opical design is the same as 35mm SLR designs. A normal lens on both will usually be a Double Gauss type. Slightly wide will be Retrofocus type while the very wide will be a Distagon variant or something similar to Schneider's Super Angulon-R used on the Leica reflex cameras. The 75mm f/4.5 is a Retrofocus, the 55mm new version is a Distagon variant and the 45mm is based on the Schneider Super Angulon-R. The potential for 67 lenses to be as sharp as 35mm is there but is rarely realized. Designers of 35mm lenses know the lenses will be used for extreme enlargements and so the designs are state of the art. The most expensive glasses are used and very little size variation is allowed in manufacturing of the lenses and barrels. The 67 lenses will not yield the lp/mm that the best 35mm lenses will but it is pretty close. The much larger film size more than makes up for it.

[jimvanson]

www.turguttarhan.web1000.com/pentax67/test.htm Link does not seem to work...

[turgut_tarhan]

There might have been a server downtime. It should work now, as I tested twice. <p><a href="http://www.turguttarhan.web1000.com/pentax67/test.htm"><b><u>The link </u></b></a></p>