Brightness of super angulon mc 5.6 and what does the xl do better?

[SeanEsopenko]

I have an older single coated super angulon f8 which I'm starting to tire of due to the dark corners. I shoot in the field and I think I'd be able to work quicker with a brighter image.

How much brighter is the 5.6? Oh and does the XL have a noticeable difference from the non-xl besides the imaging circle? I can't use much of my current lense's circle because I don't have a bag bellows for my wista 45sp field camera. But if it has a sharper, more saturated & contrasty image (like the microcontrast of a distagon or the new sigma 35mm) I'd be willing to spring for the higher price of the xl.

Any thoughts?

Edit: forgot to mention I'm looking to replace my 90mm

[Taija71A]

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Hi Sean,

You forgot to tell us *Exactly which Schneider Super-Angulon Lens... You are presently using.

Your post in the 'Title' also says 'MC' (for 'Multi Coated')... However your comment says 'Single Coated' ?

Focal Length ???
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Once, the forum members have this necessary information... They will be in a better situation -- To perhaps assist you further. Thanks!
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Best regards,

-Tim.
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[SeanEsopenko]

Woops sorry! 90mm!

[EdSawyer]

90XL is huge, and overkill for 4x5. aside from brightness, the Nikon 90/8 is the 90 to beat. the 90/4.5-5.6 will be brighter, some, but not a HUGE amount. I'd probably not switch just for that reason. do you have a fresnel? that will make a bigger difference.

[SeanEsopenko]

Yeah I have a Fresnel screen. It's meant 135mm lenses I believe.

What makes the 90mm Nikon f8 good? I'm looking for a brighter lens and one that has good multi-coating for better saturation than my current Schneider 90mm f8 single coated.

[Dan Fromm]

Sean, if your big problem is unsaturated chromes, don't shell out for a marginally better, if that, lens, before checking that your shutter is running on time, your light meter is accurate and you are using the meter properly. With chromes, overexposure kills saturation. If you're shooting color negatives, check the entire process from exposure to the final print. There are many, many ways to get to an unsaturated print. Fixing on the lens as the culprit without checking the others is wrong.

If your problem is, as you first stated, poor viewing then by all means buy a brighter lens. Oh, and by the way, ain't no 90 mm lens with less than 1 1/2 or so stops fall off center to corner on 4x5, and the best will have around one stop falloff. The 90/5.6 SAXL is, if I read Schneider's curves correctly, one stop down, center of 4x5 to corner, at f/22.

[neil poulsen]

The Nikon 90mm f8 has an image circle of 235, which parallels that of many of the f5.6 super-wide 90's. (The XL 90 is much larger.) So, that will help with the dark corners, although the image as a whole won't be as bright as the f5.6 versions.

[SeanEsopenko]

Sean, if your big problem is unsaturated chromes, don't shell out for a marginally better, if that, lens, before checking that your shutter is running on time, your light meter is accurate and you are using the meter properly. With chromes, overexposure kills saturation. If you're shooting color negatives, check the entire process from exposure to the final print. There are many, many ways to get to an unsaturated print. Fixing on the lens as the culprit without checking the others is wrong.

If your problem is, as you first stated, poor viewing then by all means buy a brighter lens. Oh, and by the way, ain't no 90 mm lens with less than 1 1/2 or so stops fall off center to corner on 4x5, and the best will have around one stop falloff. The 90/5.6 SAXL is, if I read Schneider's curves correctly, one stop down, center of 4x5 to corner, at f/22.

The main problem is illumination of the corners. I don't really have problems with saturation, I just think of it as a bonus if I can get it a little better. I do sometimes have problems with flare which I can usually mitigate with a hat. It's just that if i were to replace the sa 90mm f8 I have I might as well ensure it's mc at the same time.

So if the xl is brighter overall and has a larger imaging circle the corners should be much brighter? And it would also work for 5x7 in case I decide to jump up to a larger and more elongated format? It would probably be stellar for 6x17 too, wouldn't it?

[Leigh]

Any lens at f/5.6 will be EXACTLY the same brightness as any other lens at f/5.6.

That is the most fundamental law of photographic optics.

If it were not true, all of our exposure calculations would be worthless guesses.

Visible brightness of a ground glass image can be enhanced by using a fresnel lens, but that's an auxiliary optic.

- Leigh

[Dan Fromm]

Any lens at f/5.6 will be EXACTLY the same brightness as any other lens at f/5.6.

'T'ain't so, McGee. Coating improves transmission, and the more air-glass interfaces a lens has the more it helps. This is why the very serious photographers in Hollywood use lenses calibrated in t/stops. f/stops are geometric, t/stops are photometric and the difference can be important.

In addition, not all wide angle lenses are created equal. Lenses, including old-style w/a lenses that don't use Roosinov's tilting pupil trick, have illumination fall off as cos(theta)^4, assuming no mechanical vignetting. The tilting pupil trick can cut the fall off to as little as cos(theta)^3. At large angles off-axis, this makes a significant difference.


If it were not true, all of our exposure calculations would be worthless guesses.

They're not worthless guesses, but to some extent they are guesses, or, if you don't like the word guess, compromises.

Sean, if you want bright, don't compromise. Get the 90/4.5 Nikkor, pay the weight penalty, and don't look back. The corners will be brighter with it than with the 90/5.6 SAXL.

[Leigh]

Hi Dan,

My comments applied specifically to on-axis illumination at the image plane. I should have specified that.
Off-axis illumination can vary quite a bit depending on lens design.

Speaking of which, any reduction in transmissivity due to coatings or other factors is easily compensated during the design phase by making the diameter of the aperture corresponding to f/whatever slightly larger than would be required for unattenuated light.

T/stops are used in the motion picture industry due to its unique requirement that film spliced together that was originally shot with multiple cameras and multiple lenses should look as though only a single camera/lens was involved. This requires much more precise exposure matching than is required for any of the work we're doing with single images.

Thanks for the comments.

- Leigh

[Bernice Loui]

The XL or larger f5.6 Super Angulon, f4.5 Grandagon and etc have larger image circles than the f8 variety. The illumination from enter to edge is slightly improved only. To properly correct for light fall off in these lens designs requires using the proper center filter.

Have a look at my Thinker image in the "Praise for 5x7" Thread. This image was made on a flat light over cast day (very even and flat light) the structure is very uniform in color making it easy to see the light fall off from center to edge.
http://www.largeformatphotography.info/forum/showthread.php?57170-In-Praise-of-5x7-Post-em-!&p=1091006#post1091006

That image was made using a 115mm Rodenstock Grandagon at f22.


Bernice



The main problem is illumination of the corners. I don't really have problems with saturation, I just think of it as a bonus if I can get it a little better. I do sometimes have problems with flare which I can usually mitigate with a hat. It's just that if i were to replace the sa 90mm f8 I have I might as well ensure it's mc at the same time.

So if the xl is brighter overall and has a larger imaging circle the corners should be much brighter? And it would also work for 5x7 in case I decide to jump up to a larger and more elongated format? It would probably be stellar for 6x17 too, wouldn't it?

[ic-racer]

The f5.6 lens should be twice as bright as the f8 lens.

[Bernice Loui]

Yes, but the human eye does not and will not see it as being twice as bright. It will be perceived as brighter..


Bernice


The f5.6 lens should be twice as bright as the f8 lens.

[EdSawyer]

The special thing about the nikon 90/8 is it's an 8 element lens, most other are only 7. That, among other things, makes it basically the shaprest 90 going. Check Perez's tests.