general question on lenses and large enlargements

[monk]

Greetings Everyone!

i would like to ask what would be the "maximum enlargement" i could make with my 150mm convertible symmar and 300mm nikkor f9 lenses that would seem "sharp" even from a close inspection.(negative "optimum development",and printed on multigrade developed in dektol 1:3)
or lets put it this way:whats the biggest enlargement YOU guys did with one of these lenses?(or saw other guys work...)
i use tmax 100 and id-11 nearly all the time.
share your experiences here Please!
Thanks a Bunch!
Good light for Everyone!

 

[monk]

dont get me wrong,i dont want to start a deep line per mm thread here(ok,maybe just a surface touch that i can understand; ) )
was just wondering if you have experiences with this lenses "big" enlargement wise, and what would that be?
would i need a "Special" lens to make Huuge murals,or my nikkor or symmar could do the job(of course,im just talking about theory here with optimum development of the negative etc-etc..)
monk

 

[Dan Fromm]

You can't avoid it. If you believe Messers. Perez and Thalmann's resolution estimates (see http://www.hevanet.com/cperez/index1.html) and that an acceptably sharp print has to resolve at least 8 lp/mm (some posters here prefer as little as 5 lp/mm) in the corners then 8x is as big as you can go. That's with outstanding technique, so you can't count on that much.

My best 8x10 prints from really good Kodachrome 25 negs (35 mm, of course) won't stand close examination. My fault, I could have sacrificed DoF and shot at a larger aperture.

That's reality. Fuzzy.

 

[ic-racer]

Neither one of those lenses is best for enlarging. If you are enlarging 8x10 the 150 won't even cover.

 

[RobC]

Like all photography questions the answer begins with "It Depends".

You will hear that T-Max (and some other B+W films) are capable of resolving 200 lp/mm on the negative. However, what you rarely hear is that is only at a contrast ratio of 1000:1. This means using a special test target of black and white lines where the contrast ratio between the black and white lines is 1000:1 which is 10 stops. Very Very Very rarely if ever in the real world would you ever find a subject which has that contrast ratio in the finest detail of your subject so you can forget any notions of achieving 200 lp/mm in the negative. The more realistic lower contrast ratio in the fine detail of your subject is 1.6:1 and when the contrast ratio drops to that you will only get 63 lp/mm on the negative (for Tmax 100 quoted by kodak).

So in reality the achievable lp/mm on film is limited by the subject finest detail contrast ratios which will be somewhere between the the upper and lower limits of what the film is capable of. And there's the crux of it. Your subject will have varying contrast ratios throughout it. Some parts will be fairly high and some parts very low so the resolution throughout your negative will vary greatly. If you can achieve 100 lp/mm on film you will be doing extremely well but that will only be areas fine detail with strong subject lighting providing high contrast. Other areas not in direct lighting will have very low contrast and low resolution.

Most modern lenses can easily resolve the subject detail that is available to them from the subject contrast ratios.

So I would assume that average lp/mm you can expect in your negative is say 60 lp/mm and that will allow you a 6X enalrgement factor which has some margin of error thrown in.

However, it isn't as simple as that becasue it doesn't take into consideration the human eyes ability to resolve detail (the so called 8 lp/mm) at 10 inch distance. The print sniffers of this world will cry foul when they put thier greasy little noses up against your print but ignore the fact that when you stand back and look at a print from a sensible viewing distance related to the prints size, you don't need anywhere near 8 lp/mm in the print for it to look sharp and highly detailed.

It's the combined print resolution and viewing distance that determine what will look good. So once again there is no fixed answer becasue it depends on all these factors. But your 60 lp/mm on film will be good enough for bigger than 6X enlargements if they are not viewed from 10 inches away but several feet away.

There is a formula somewhere posted on the web for calculating required print resolution for viewing distance.

Note1: F22 which is the default goto aperture on a 150mm lens on 4x5 LF is diffraction limited(Rayleigh Criterion) to 70 lp/mm so you could never achive more than that at F22.

Note2:

A 150mm enlarging lens at F11 producing a 12X enlargment would be using an effective aperture of F143 capable of producing 13 lp/mm in the print. But starting from 60 lp/mm in the neg you would only have 5 lp/mm from the original subject. Your enlarging lens is not the limiting factor except that they are optimised for certain enlargement factors, 150 lenses around 6X with a few exceptions designed for bigger enlargements such as Rodagon G lenses. But they can't get higher resolution than exists in the negative so really for a 4x5 neg you are looking at 12X before the image really starts to break down and that is only providing you have excellent taking lens, excellent subject fine detail contrast ratios, excellent dof in subject, excellent technique, perfectly aligned enlarger, excellent enlarging lens etc etc etc otherwise all bets are off. Hence my 6X suggestion and Dans 8X suggestion which are ball park about as good as it gets depending on your lp/mm in final print criteria.

 

[RobC]

taking lenses don't work well for enlargments. It is not a reverse process. Taking lenses are not usually designed to be flat field whereas enlarging lenses are. Then taking lenses are optimised for much greater distances than your lens paper distance.

 

[DREW WILEY]

There's a LOT more to making crisp enlargements than just the taking lens. You're only as good as the weakest link in the ENTIRE workflow.
And you fail to even tell us what format film you are working with, though it would be appear to be 4x5. I specialize in very crisp nose-to-nose enlargements on high gloss papers, optically printed, and know the limitations. Modern camera lenses are the least of your problems.
But that 300M will be a lot sharper than the other lens. After that, really good enlargements require a serious commitment in darkroom gear. You can hypothetically make prints as big as paper is available and you have facilities to expose and process. But anyone who claims a truly sharp 12X magnification, or even 8X magnification is stretching it. When I want big prints, I shoot 8x10 film, and even then rarely print bigger than 30x40. Just depends on your personal expectations, what you mean by "sharp".

 

[monk]

Gentlemen!
Sorry,i ment using the lenses above as taking lenses for 4x5 film and that film would be enlarged..i didnt mean to use those lenses as enlarging lenses..
i should shut the f.. up and learn english first
Truly Sorry!

 

[Old-N-Feeble]

You're doing well, monk. APUG is an extremely diverse community spanning many processes with members around the globe. Sometimes it takes a few posts to make one's questions or answers fully understood. That's okay. This is a world community with understanding patience. I love it here.

 

[Alan Gales]

If you go the hybrid route and get your negatives drum scanned they say that the skill of the drum scan operator has a lot to do with the quality of the enlargements too.

Your English is fine. It's great that you can speak multiple languages. I only speak English and Pig Latin. Ooday ooyay peaksay igpay atinlay?

 

[monk]

You're doing well, monk. APUG is an extremely diverse community spanning many processes with members around the globe. Sometimes it takes a few posts to make one's questions or answers fully understood. That's okay. This is a world community with understanding patience. I love it here.

HA-HA
if i look at the picture next to your post,i could think at my paranoid moments that "you" are created by another user with another name,and everything you say is irony
i love you!

 

[Old-N-Feeble]

No irony here... just trying to make you comfortable on APUG. I appreciate the sentiment and I like you too. Love... I think we're not THAT close, ha ha!!

 

[monk]

If you go the hybrid route and get your negatives drum scanned they say that the skill of the drum scan operator has a lot to do with the quality of the enlargements too.

Your English is fine. It's great that you can speak multiple languages. I only speak English and Pig Latin. Ooday ooyay peaksay igpay atinlay?

HA-HA!!!love your Pig Latin
the hybrid route tells as well that i have to get a better darkroom print maker,that is the reason im here forto learn from you guys!
Thanks RobC and Dan for the very imformative comments!And everyone who shared opinions:Thank You!
AlltheBest Everyone!

 

[monk]

No irony here... just trying to make you comfortable on APUG.

indeed,your comment made me feelcomfortable on APUG!Thank You!
I appreciate the sentiment and I like you too. Love... I think we're not THAT close, ha ha!!