New for large format camera

[asd]

Got a Sinar 8x10P camera days ago and shot some velvia slides with Schneider Super Angulon 210mm and Apo symmar 300mm. When examine the films after processing with a 10x loupe, find out that the images was not so sharp.

I shot landscape all the time. Always use f45 or f64 with a heavy tripod.

Could someone help me!

[Don Hutton]

Try the viewcamera websight - their are plentie of articals their on diphraction.

[paul08]

Hi asd: First, try those shots at f22-32. And how is the focus on the ground glass?

[Tom Perkins]

I agree with Don that there may be some diffraction going on; also, I never found my 8x10's to be particularly sharp under a loupe. Think about how little depth of field you would have with a 300mm lens on 35 mm and then imagine what a challenge it is to spread the same focal length out over 80 square inches of film and keep everything sharp and in focus. Even though camera movements and the smaller aperture can be used to move and enlarge the plane of focus, it is still very challenging to get a tack sharp 8x10.

[Paul Kierstead]

So, an 80"x100" (over 6'x8'!!) print made from the tranny woudn't be that sharp when viewed extremely closely? Not surprisingly.

Think about it. With large formats, you need to think differently.

[Peter De Smidt]

Check that your ground glass is seated properly. It's also possible that your holders are off. But as others said you on negative resolution per unit of area will be less than smaller formats, but you will be enlarging much less of course.

[Brian Ellis]

Diffraction isn't a problem if you're just viewing 8x10 slides (i.e. no enlargements). I suspect the reason they don't look sharp is the 10x loupe. That's a lot of magnification to be using.

[Sass Quatch]

I just checked one of my prints with a 7X loupe. It was shot with a 300mm Rodenstock Apo Sironar S. The print is sharp when viewed without magnification, the view through the loupe is not. Most people do not blow up 8x10 to that degree. A few years ago there was an Avedon retrospective at the Metropolitan Museum Of Art. The prints were very large. They were not sharp either. He used an 8x10 Deardorff.

[David Karp]

Check your groundglass to make sure it is installed properly.

Also, you need a tripod and head that are sturdy enough to support an 8x10.