4.0 or 5.6?

[scinysnaps]

Is there really a HUGE diff between a Rodagon 80mm 4.0 and and 5.6 or the Companon 4.0 and 5.6??
Is it worth the extra money?

 

[keithwms]

No.

 

[scinysnaps]

Glad to know.
Cheers

 

[Christopher Walrath]

All that would be accomplished by the 4.0, well, two things really. First, reduced hyperfocal distance, not a huge selling point for printing. But a slightly brighter view of the negative for focusing when stopped open. 5.6 should be more than adequate.

 

[Shaggysk8]

Which I would say if you use XP2 it would be a bonus, or any thick emulsion negs but all my panF negs are easy to see at even F11

 

[Christopher Walrath]

True. I can see my negs well at f/11 (TMY2) but the more light the better.

 

[photomem]

I have always wondered why enlarging lenses open up to f4. Its not like anyone in their right mind would try to print at that aperture.

 

[BetterSense]

If you even want to make very large prints, or very slow materials, the larger apertures can really come in handy.

 

[David A. Goldfarb]

Faster lenses often have better corner sharpness, so they can be used at wider apertures for large prints or printing in quantity. You may not want to use an f:4 lens wide open, but it might be sharper at f:8 than an f:5.6 lens. Usually when enlarging lenses come in two maximum apertures, the faster one is a 6-element plasmat, and the slower one is a 4-element tessar type. There are 3-element enlarging lenses that are best avoided in most cases. Some of the tessar-types are pretty good actually. I had a 4-element EL-Nikkor for medium format that was quite good and had excellent contrast, but I eventually traded it for a 90mm Apo-Rodagon when enlarging lenses became absurdly cheap.

 

[Existing Light]

What about contact printing? Would the extra stop be beneficial then?

Please note that I've never done contact printing. I'm just assuming that you place the negative on top of the paper and line them up under the lens of a regular enlarger. Maybe that's not how it's done, and i'm just dumb

 

[Christopher Walrath]

Either in a contact printing frame or, at the very least, a meticulously cleaned pane of glass. Dulled edges of course.

 

[edtbjon]

What about contact printing? Would the extra stop be beneficial then?

Please note that I've never done contact printing. I'm just assuming that you place the negative on top of the paper and line them up under the lens of a regular enlarger. Maybe that's not how it's done, and i'm just dumb

How to get good contact between the negative and the paper, is a story of its own. (Please search for it, there is plenty of information and I recon, even a subforum here on Apug devoted to it.)
But when you use the enlarger as a light source, there is a possibility that there is some light fall off at the edges at full opening. Now, "real" contact printers don't use enlargers, only a selection of light bulbs to choose from. Maybe funny, but it's not a joke...

//Björn

 

[RalphLambrecht]

I have always wondered why enlarging lenses open up to f4. Its not like anyone in their right mind would try to print at that aperture.

It is easier to focus wide open. Stop down for printing.

 

[jeffreyg]

I agree with Ralph. I've been printing for over thirty years in various formats. My enlarging lenses vary from f2.8 to f5.6 at their widest openings. I focus wide open on the grain and stop down to f8 or f11 to print. Works fine.
Jeff

 

[keithwms]

If I try to grain focus with any of my enlarging lenses wide open it literally hurts my eyes. And they are mostly f/4 and f/5.6 lenses. I also don't see how to grain focus at the corners with the enlarging lens wide open. Maybe with an apo process lens, but certainly not any of the others that I have used.

 

[RalphLambrecht]

If I try to grain focus with any of my enlarging lenses wide open it literally hurts my eyes. And they are mostly f/4 and f/5.6 lenses. I also don't see how to grain focus at the corners with the enlarging lens wide open. Maybe with an apo process lens, but certainly not any of the others that I have used.

They are quite bright, you are correct, but no problem focusing into the corners.

 

[jp80874]

What about contact printing? Would the extra stop be beneficial then?

Please note that I've never done contact printing. I'm just assuming that you place the negative on top of the paper and line them up under the lens of a regular enlarger. Maybe that's not how it's done, and i'm just dumb

I use a 300mm Rodagon on my 8x10 enlarger for a light source when making 7x17 contact prints in a contact printing frame. I vary the f stop to vary the exposure time. If I need to dodge or burn this give workable times for such activity. It is much harder than d&b in an enlarger because you can not see the image, just guess or calculate relative to the print frame.

John Powers

 

[keithwms]

... but no problem focusing into the corners.

Ralph, by that I meant (as I am sure you know): some enlarging lenses will not be sharp enough to judge the edges when shot wide open. It's not worth going through lens-by-lens here, but... anyone with a grain focuser can look at corner sharpness as a function of aperture.

From an optical standpoint, it's not obvious to me that the corner focus you establish with the lens wide open will be identical to the corner focus when it is stopped down. Yes, I am saying that the focus may drift with aperture... at least for some glass. This seems very nonintuitive because we focus wide open through our cameras all the time. I don't know if anyone else has seen this effect, but I did see it with some no-name wide enlarging lens at high mag. Generally it's something that we take for granted, that the lens is sufficiently corrected to give consistent focus through all the apertures. And that intuition is mostly correct... I am just saying, beware. When we judge focus, we do so in relative terms... we compare in-focus to out-of-focus. It's not like bells go off when we hit the focus right on, it's always comparative... and thus your eyes can be tricked. At least by some (inferior?) enlarging lenses.

Of course, the other part of this (and perhaps the more important part in general) is that if the lens is not sharp to the corners when shot wide open then we can unwittingly make some error in determining optimal focus there. So of course... best policy, esp. if you want to enlarge wide open because of shorter times or whatever, is to check multiple points with the grain focuser. And try a few different apertures as well, it may surprise you.

And of course none of my comments are directed at Ralph, though he may wish to say more...

~~~

Anyway, just a supplementary word of caution that I think is worth repeating, especially for any newcomers to optical enlarging: if you use a grain focuser, do be attentive to the health of your eyeballs! Your eyes, when adjusted to typical darkroom conditions, are quite vulnerable to bright light, such as through a grain focuser with your lens wide open.... photographers need to protect their most valuable faculty! So be patient and give your eyes plenty of time to adjust.... I didn't do this, just once, and had a painful injury for several weeks. I suppose I burned my retina. Hurt like hell, and there is probably some amount of permanent damage. Best policy, I feel, is to stop the lens down to f/16 or so, then open the lens up gradually.

 

[RalphLambrecht]

Keith

I see no option. I have a terrible time finding the 'sweet' spot of focus, unless the lens is wide open. My enlarger is not bright enough to pose any danger to my eyes, and it has a neutral density filter built-in, should I ever need it. Also, I mainly use a 20x grain magnifier, which is a dimmer instrument then the Peak with its 10x magnification.

However, your warning is justified and your suggestion is valuable. We need to protect our eyes.

 

[Martin Aislabie]

Not possessing a ND Filter in the head of my DeVere, I just dialled in 50Y + 50M + 50C

It meant not only my retinas remained in tact but also I could use sensible f stop settings and exposure times

I found (by chance) that one of my top name German enlarger lenses focus shifted as it stopped down – which came as a bit of an unpleasant surprise.

Consequently, I have retired it to paperweight duties

Martin

 

[RalphLambrecht]

Not possessing a ND Filter in the head of my DeVere, I just dialled in 50Y + 50M + 50C

It meant not only my retinas remained in tact but also I could use sensible f stop settings and exposure times

I found (by chance) that one of my top name German enlarger lenses focus shifted as it stopped down – which came as a bit of an unpleasant surprise.

Consequently, I have retired it to paperweight duties

Martin

I can't do that easily, because I'm using magenta and yellow for contrast control.

 

[scinysnaps]

So what's the bottom line folks?
Is it worth the extra money for an 4.0 over the 5.6
I am looking at the Companon 80mm

 

[keithwms]

Now you changed the question! Before it was: is there a huge difference... and the answer is no, there isn't a huge difference.

 

[outwest]

But there can be quite a bit of difference between a Componar, a Comparon, a Componon, a Componon-S, and an Apo Componon HM.

 

[scinysnaps]

OK, sorry for the confusion. We have to some degree determined that there is NOT a lot of difference except for some situations.
All things considered, I am comparing a Componon/Componon-S 4.0 to a Componon/Componon-S 5.6
I will not be doing any contact printing, nor anything above 16x16 from my 6x6 negs

As a footnote, I already own a 5.6 Componon... The question would be: Is it worth the extra expense to upgrade to a Componon/Componon-S 4.0
Would I be able to the tell the difference ( apart from brighter focusing ) in the aforementioned applications?